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The Asian monsoon influences the lives of more than a third of the world's population, and understanding its spatial and temporal variability is fundamental to sustainable development. The complex dynamics of this climatic system are therefore of broad scientific and societal interest. In this virtual special issue (VSI), we present 19 papers dealing with the Asian monsoon since the Last Glacial Maximum (LGM, ∼21 kyr BP), with a focus on understanding variability and forcing mechanisms. Findings use recently developed quantitative reconstructions combined with numerical simulations, and present novel insights as follows: (1) analyses of comprehensive datasets of pollen, diatom, brGDGTs, oxygen and hydrogen isotopes and frequency magnetic susceptibility, as well as an innovative algorithm model for the lake energy-water balance, improve the reliability of quantitative reconstructions of Asian monsoon climate variations; (2) studies of quantitative climate parameters in central East Asia show that mean annual temperature (MAT) was ∼5 °C (or ∼ 7.9 °C using brGDGTs) lower during the LGM, ∼1.5 °C (±41% using brGDGTs) higher around the Holocene thermal optimum (HO) and mean annual precipitation (MAP) varied between 30 and 150% with marked seasonality during 8–5 ka; (3) dynamical downscaling palaeoclimatic simulations improve the accuracy of past monsoon variations, revealing strong variability in monsoon precipitation across the LGM and HO. The holistic study of Asian monsoon variations at orbital to centennial timescales in these VSI papers presents reliable observations of monsoon variability and its driving mechanisms, providing high-resolution quantitative paleoclimate reconstructions that fill existing gaps in spatial coverage, as well as offering an improved understanding, thorough numerical simulation, of coupled sea-level change and vegetation feedbacks. • An introduction to Asian monsoon variations over the past 21 ka. • Transfer functions, sedimentary records and numerical simulation are developed for studying past Asian monsoon. • Averaged MAP in East Asia varied between 30-150 % over the past 21 ka. [ABSTRACT FROM AUTHOR]

Through the Earth's ∼ 4.54 billion year history, icehouse climates have been relatively short-lived but have exerted a significant impact on the evolution of the habitable environment. These icehouse episodes, such as those that occurred in the Cryogenian, mid-Ediacaran, Late Ordovician, and Late Paleozoic, developed through the complex interaction of Earth System processes; however, there is still ongoing debate regarding the causes, processes, and consequences of these glaciations. To improve our understanding of the past history of icehouse climates and the responses of the Earth System, we present this new special issue entitled The Earth System during Icehouse Climate Modes: Contributions from Glacial Records in China. This special issue includes eighteen papers that focus on four major icehouse events: the Cryogenian Snowball Earth glaciations (Sturtian and Marinoan global glaciations), the Ediacaran glaciation, the Ordovician glaciation, and the late Paleozoic Ice Age. This collection of papers provide novel insights into glacial processes, marine environments, and chemical weathering through key intervals of Earth History. We anticipate that this special issue will attract wide interest across the geosciences field. [ABSTRACT FROM AUTHOR]

The Pliocene Model Intercomparison Project (PlioMIP) was initiated in 2008. Over two phases PlioMIP has helped co-ordinate the experimental design and publication strategy of the community, which has included an increasing number of climate models and modelling groups from around the world. It has engaged with palaeoenvironmental scientists to foster new data synthesis supporting the construction of new model boundary conditions, as well as to facilitate new data-model comparisons. The work has advanced our understanding of Pliocene climates and environments, enhanced our knowledge regarding the ability of complex climate and Earth System models to accurately simulate climate change, and helped to refine our estimates of how sensitive the climate system is to forcing conditions. In this community protocol paper, we outline the scientific plan for PlioMIP Phase 3 (PlioMIP3). This plan provides the required guidance to participating modelling groups from around the world to successfully set up and perform PlioMIP3 climate model experiments. The project is open to new participants from the scientific community (both from the climate modelling and geosciences communities). In PlioMIP3, we retain the PlioMIP2 Core experiments (Eoi 400 , E 280 ) and extend the Core requirements to include either an experiment focussed on the Early Pliocene or an alternative Late Pliocene simulation (or both). These additions (a) allow a comparison of Early and Late Pliocene warm intervals and help build research connections and synergy with the MioMIP (Miocene Model Intercomparison Project - also known as DeepMIP-Miocene) and PlioMioVAR projects (Pliocene-Miocene Variability Working Group), and (b) create an alternative time slice simulation for 3.205 Ma (MIS KM5c) through removal of some of the largest palaeogeographic differences introduced between PlioMIP1 and 2 resulting in minimal land-sea mask variations from the modern. In addition, we present ten optional experiments designed to enhance our assessment of climate sensitivity and to explore the uncertainty in greenhouse gas-related forcing. For the first time, we introduce orbital sensitivity experiments into the science plan, as well as simulations incorporating dynamic vegetation-climate feedbacks and an experiment designed to examine the potential significance of East Antarctic Ice Sheet boundary condition uncertainty. These changes enhance palaeo-to-future scientific connections and enable an exploration of the significance of palaeogeographic uncertainties on climate simulations. • This paper presents the community agreed science plan for the 3rd phase of the Pliocene Model Intercomparison Project (PlioMIP3). • Experiments are prioritised/designed to enhance our knowledge of Pliocene and its use in understanding future climate change. • Guidance on model set-up, timescales, format of the model outputs and where these should be stored is outlined. • Information for modelling groups to access the required boundary conditions underpinning model experiments is provided. • Linkages between the climate modelling effort and ongoing co-ordinated geological proxy synthesis is described. [ABSTRACT FROM AUTHOR]

The Asian monsoon has progressively become a megamonsoon system since the early Cenozoic. To improve our understanding of the complex nature of the Asian monsoon system, involving strong interactions between atmospheric, oceanic and terrestrial systems across different timescales, we present this special issue, entitled Cenozoic climate change in Asia. The special issue is dedicated to Prof. Zhengtang Guo in honour of his distinguished contributions as Editor-in-Chief of Global and Planetary Change to our understanding of the long-term evolution of the Asian monsoon system. The special issue consists of nineteen papers, grouped into three categories, that address Cenozoic climate change, mainly in Asia. The first category focuses on the plate tectonic-scale and considers how changes in palaeogeography and palaeotopography have shaped climate evolution. The second category addresses orbital- to suborbital-scale climate change and, in particular, explores the links between low-latitude insolation, high-latitude ice sheets and the Asian climate. The third category addresses millennial- to decadal-scale climate changes. In addition, past human-environment interactions are also discussed. These studies provide important insights into our understanding and prediction of both natural variability and human-induced climate changes in Asia and their linkages with global climate within the Earth System. • This special issue dedicated to Prof. Zhengtang Guo. • Asian climate variabilities across multiple time scales. • Past human-environment interactions in monsoonal East Asia. • Integration of Earth's interior and surface tectonic-climatic processes. [ABSTRACT FROM AUTHOR]

In High Mountain Asia, human-induced climate warming threatens the cryosphere. Expected long-term reductions in future runoff from glacial catchments raises concerns regarding the sustainability of these natural 'water towers' and the implications of reduced water availability for regional human and ecological systems. Ice-debris landforms (I-DL), containing ice whether moving or not include rock glaciers and ice-cored moraines, and are likely to be climatically more resilient than debris-covered and debris-free glaciers. Recent work has shown that rock glaciers contain globally valuable water supplies yet over High Mountain Asia information regarding their number, spatial distribution, morphometric characteristics and water content are scarce. Here, we present the first systematic estimate of the current extent and distribution of rock glaciers for a subset of High Mountain Asia (the Himalaya). A sample of 2070 intact and relict rock glaciers were digitized on Google Earth imagery from the Western, Central and Eastern Himalaya regions and then quantitative and qualitative characteristics were analysed regionally based on topographic data from the NASA Shuttle Radar Topography Mission (SRTM) Version 3.0 and then aggregated across the Himalaya using an "upscaling" method. The majority of the digitized landforms (∼65%) were categorised as intact rock glaciers (i.e., ice-debris Landforms, or I-DLs, containing ice) and the remainder as relict rock glaciers (i.e., discrete debris accumulations or DDAs, not containing ice). They range in elevation from 3225 to 5766 m a.s.l., with the lowest in the Central Himalaya. Sampled relict and intact rock glaciers are primarily situated on northern quadrants. Over the entire Himalaya, we identified ∼25,000 landforms, with a total estimated areal coverage of 3747 km2. The area upscaling method was validated in the Manaslu region of Nepal using high-resolution Planet data (5 m) and freely available, fine spatial resolution optical satellite data accessed through Google Earth Pro and ESRI basemaps. In absence of complete rock glacier inventories over the Himalaya, our approach proves useful to investigate the nature, distribution and infer potential future behaviour of these landforms across the Himalaya in a changing climate. • Climate change in the mountains of the Himalaya is driving glacier melting and associated changes in water supplies to downstream areas. • This impacts the water supplies for hundreds of millions of people and ecosystems and is seen as a great challenge for future sustainable development in this part of central Asia. • However, large volumes of ice are contained are contained in rock glaciers (ice-debris landforms common in high arid mountains) although research on the number and extent of these in the Himalaya is limited. • In this paper, we present the first systematic estimate of the current extent and distribution of rock glaciers for the Himalaya and show that around 25,000 landforms exist in the region, with a total estimated areal coverage of 3747 km2. • We argue that rock glaciers constitute hydrologically valuable long-term water stores and, with continued climatically-driven glacier recession and mass loss, their value is likely to become increasingly important. [ABSTRACT FROM AUTHOR]

Observations of ice sheet stability in Antarctica in the past, during significantly warmer climatic periods than today, are hampered by a paucity of continental outcrops but they are essential if we are to test and more fully understand established concepts of ice sheet growth and decay and robustly predict Earth's future during rapid global warming. In this paper we use the unique terrestrial record preserved in the three most southerly volcanoes on Earth to reconstruct Antarctica's environmental landscape in the Transantarctic Mountains for three time slices (at 20.1, 19.31 and c. 17 Ma). We demonstrate that the East Antarctic Ice Sheet margin was highly dynamic and fluctuated greatly during the Early Miocene. The period included a much-reduced ice cover that left the southern Transantarctic Mountains virtually ice-free, although a few tidewater glaciers reached the shores of the Early Miocene Ross Sea (Sheridan Bluff; 20.1 Ma); and a substantially thicker, much more voluminous ice mass (represented by volcanism at Mount Early; 19.31 Ma). An intermediate stage of ice retreat is also indicated (at c. 17 Ma), when the East Antarctic Ice Sheet had again withdrawn to behind the Transantarctic Mountains. It is represented by a subglacial volcanic centre identified remotely by aerogeophysics and sampled only as glacial erratics. The associated ice cover at c. 17 Ma had a relatively low surface elevation but it was confluent with thin ice domes that covered the adjacent mountains. Although the ice margin probably did not extend down to the Ross Sea coast, several glaciers fed icebergs into the Ross Sea. The large ice sheet indicated by the Mount Early volcanic centre is the only known physical record of a significant glacial event that took place at 19.31 ± 0.32 Ma ('Mount Early glacial'). The records examined at the other two volcanic sites correspond to eruptions during periods of substantially reduced ice in Antarctica, of which that at 20.1 ± 0.4 Ma is the most remarkable ('Sheridan Bluff interglacial'). The causes of the extreme variations in ice sheet thickness and extent indicated are uncertain but they occurred during a period of rapidly fluctuating atmospheric CO 2 compositions. Although Milankovitch astronomical forcing probably also played a significant part, the results suggest that the East Antarctic Ice Sheet was highly susceptible to comparatively slight changes in CO 2 during the warm Early Miocene. • Transantarctic Mountains landscapes reconstructed using glaciovolcanic sequences for three time slices in the Early Miocene • Large, deep, unfrozen freshwater lake identified at 87°S and c. 2000 m elevation, not predicted by current modelling • Very large ice sheet recognized, more expanded than today, which overtopped the Transantarctic Mountains • Ross Sea margin of the East Antarctic Ice Sheet was highly dynamic between 20 and 17 Ma • Ice sheet margin was highly sensitive to comparatively small changes in CO 2 [ABSTRACT FROM AUTHOR]

Interactions among different large-scale ocean-atmosphere coupled modes are exceptionally complex. Diverse scale modes interact through oceanic circulations, ocean-atmosphere heat fluxes, and atmospheric bridges, thus affecting both the global weather system and long-term climate changes. This paper presents a review of the interaction mechanisms among six ocean-atmosphere coupled modes (ENSO, PDO, IOD, AO, NAO, and AMO) and their impacts on the South and East Asian Monsoon. Identifying the changes in the dynamics and energy budgets caused by the spatial structure evolution and amplitude change of various ocean-atmosphere coupled modes can yield a better understanding of their forcing effects on climate change. These effects are not only restricted to surrounding regions, but also significant interaction is found between the distant equator and the polar region. Interactions between various ocean-atmosphere coupled modes occur through Rossby wave activity, westerly airflow, cyclone circulation, and pressure gradients. However, because of the complexity of the relationship between multiple factors, it remains difficult to clarify the driving mechanism of each coupled mode change. More importantly, predictions based on long-term observation data are still a weak link in climate change research. This review summarizes the current knowledge on the interaction among the six ocean-atmosphere coupled modes, thus uncovering their impacts on South and East Asian Monsoon from a global perspective. • None of the ocean-atmosphere coupled modes exist independently. • Atmospheric bridges and ocean heat transfer exert an important impact on climate. • Circulation anomalies are triggered through waveguide in the mid-latitude region. • The equatorial region promotes vortex to affect the middle–high latitude regions. [ABSTRACT FROM AUTHOR]

This paper adds to the literature on the determinants of international migration. First, we offer a joint analysis of the driving forces of migration capturing year-to-year variations and long-run effects. Second, we analyze the dynamic response of migration to shocks to its determinants. We start by presenting a theoretical model that allows us to model migration as an augmented gravity equation. We then construct a rich panel data set with 16 destination and 198 origin countries between 1980 and 2015. We find that climate variables are important drivers of migration flows in our sample. We then estimate a panel vectorautoregressive model showing that the dynamic response of migration is very different across shocks to different driving forces. These findings add to the discussion about the effects of climate shocks on mobility and the concept of trapped population. Our findings carry implications for national and international immigration policies. • This paper adds to the literature on the determinants of international migration. • We construct a panel data set with 16 destination and 198 origin countries from 1980 to 2015. • Climate change is a more important driver than income and political freedom at origin together. • The dynamic response of migration is very different across shocks to different driving forces. • Our findings add to the discussion about the effects of climate shocks on mobility and the concept of trapped population. [ABSTRACT FROM AUTHOR]

Floods are one of the gravest natural hazards for societies, worsened by population growth, unchecked development, and climate change. From a Global Change perspective, past extreme events merit particular interest because they can be linked to wider climate and environmental changes, introduce perturbations. During the last decade, knowledge of long-term flood frequency and magnitude has been improved by extracting data from different types of archive. But, despite advances in dating methods, proxies and statistical techniques and efforts to identify atmospheric drivers, some fundamental questions remain unresolved. The Special Issue entitled "Pluridisciplinary analysis and multi-archive reconstruction of paleofloods" in the journal Global and Planetary Change addresses these uncertainties and complexities by assembling a selection of studies, which were first presented at the Past Climate Changes (PAGES) Open Scientific Meeting held at Zaragoza in 2017. In this introductory paper, the guest editors outline the 17 research contributions and meta-data from the 17 paleoflood studies were systematically analyzed in terms of i) geographical distribution; ii) methodologies applied; iii) types of archives; iii) numbers of flood series compiled and iv) spatial and temporal resolution of paleoflood data. The data indicate that paleoflood studies focused on fluvial depositional environments show a higher rate of integration with other types of paleoflood archive (mean of 4.5 types of archive) than studies focused on documentary sources (mean of 3.5) and lake sediments (mean of 2.4). We suggest that this strategy of archive integration has been adapted to effectively compensate for the higher uncertainties of fluvial deposition in floodplains. Statistical processing of the meta-data shows quantitative associations between specific types of flood archive and offers a solid platform for designing the optimal approach for multi-archive paleoflood research. A qualitative review and visual comparison of the 17 paleoflood series shows some consistent trends and breaks but also notable differences within and between regions. While a trend of increased flooding since 4-5 ka BP is evident, the lack of synchronicity between breaks and the coeval increases and decreases in fluvial activity is manifest. The majority of studies in the Special Issue do denote the 19th century – including the youngest cool climate pulses during the Little Ice Age – as a particularly flood-rich period. It is more difficult to assess the 20th century because of social changes, population growth and extensive river modification. Despite the mentioned uncertainties, 10 of 14 papers do not record the 20th century as an exceptional flood period. Assessing the effects of human impact on paleoflood calendars and disentangling anthropogenic from natural drivers are major challenges in integrated paleoflood analysis. It is concluded that the interpretation of flood series is complex as landscapes and flood drivers are heterogeneous and systems show different sensitivities to flood control and drivers. Thus, the study of past floods, from historical and natural archives, is challenging but also offers unparalleled opportunities to document low-frequency, large-magnitude flood events, which occurred under a broad range of climate and/or environmental scenarios, and, probably, the only way to reconstruct robust paleoflood series. • Guest editor's introduction in the Special Issue (SI) on paleofloods. • Meta-data and factor analysis (FA) of 17 paleoflood studies of the SI. • Conceptual model of multi-archive paleoflood integration. • Trends of paleofloods, natural and human drivers from the early Holocene to present. • Scoop and limitations of multi-archive paleoflood integration. [ABSTRACT FROM AUTHOR]

Based on the Shidi-1 drill core, this paper presents new and highly time resolved carbon isotope data (δ13C carb) for the Early Ordovician through Early Silurian of the Yangtze Platform, South China. Five carbon isotopic shifts (C1-C5) through the late Tremadocian to the Katian have been recognized in the Shidi-1 drill core recordings. Together with previously published isotope data, a composite carbon isotope curve for the Yangtze platform, permits the identification of a continuous Ordovician carbon isotope trend with five prominent carbon isotope shifts; including the TSICE, the Late Tremadocian positive Isotopic Carbon Excursion (LTICE, named herein), the Late Floian Rise, the MDICE and the Pagoda Isotopic Carbon Excursion (PICE, named herein). The identification and documentation of these anomalies further strengthen the regional and global correlation of the Ordovician succession on the Yangtze platform. The long-term trend in carbon isotopes indicates that organic carbon burial increased gradually throughout the Great Biodiversification Event (GOBE). A tipping point is also marked by the Dapingian-Darriwilian border, which is followed by a notable shift in the environment and creatures in the middle Darriwilian. • A continuous high-resolution δ13C carb curve for nearly the whole Ordovician of South China. • Six prominent and globally comparable carbon isotope shifts have been recognized. • Complied δ13C carb data suggest the important turnover of organisms and environment in the Darriwilian. • The δ13C carb values suggest the increased burial rates of organic matter throughout the Ordovician related to GOBE. [ABSTRACT FROM AUTHOR]

Historical studies of human interaction with climate are one approach through which to understand responses to environmental stress today. Most studies of vulnerability are based upon short timeframes in the recent past and so may focus on its symptoms rather than its underlying causes, or derive exclusively from systems-based approaches that can present historical change without recourse to human agency. This paper makes extensive use of the historical written record to analyse the comparative root-causes of the vulnerability and resilience of rural farming communities to drought over a period of three centuries (1505–1830) in the area between the Zambezi and Save rivers in southern Africa. The paper first considers vulnerability, resilience and adaptation as temporal frameworks, and analyses evidence for drought and its impacts in the pre-colonial past. It then reconstructs agro-ecosystem, livelihood and institutional vulnerability for six societies and settlements over the long-run using an indicator approach. The resultant trajectories of vulnerability are discussed in the context of the differential impacts of past drought, through which the decisive drivers and constraints of vulnerability and resilience are identified. The paper concludes with a number of key themes from this long-run analysis for contemporary vulnerability and adaptation to climate change, and points to the importance of institutional adaptation, normative goals, and uneven distributions of power. [ABSTRACT FROM AUTHOR]

Extreme climate events are hotspots in global change. However, research on the changes in future compound events and population exposure is still limited. Leveraging from the data of the sixth phase of the Coupled Model Intercomparison Project (CMIP6), this paper aims to analyze the temporal and spatial changes of global compound temperature and precipitation extreme events in the future. We also predict the risk of population exposure and quantify the contribution of different factors to exposure. The results show that: (1) In the next 80 years, compound hot-dry event (CHDE) will increase at a rate of 0.02, 0.03, and 0.08 days per decade under the three scenarios of SSP1–2.6, SSP2–4.5 and SSP5–8.5, respectively. By comparison, compound hot-humidity event (CHHE) shows a downward trend under the three scenarios, with a downward rate of 0.01, 0.02, and 0.11 days per decade, respectively. (2) Under the SSP1–2.6 and SSP2–4.5 scenarios, CHDE and CHHE have two or more mutation points. Under the SSP5–8.5 scenario, CHDE shows a significant upward and CHHE shows a significant downward trend in the middle and late 21st century. These two indices exhibit periodic changes in all three scenarios (3) South Asia, West Asia, and Northeast Africa have higher CHDE values, while regions with higher CHHE values are located in North Asia and Greenland. (4) Climate change is a major factor affecting population exposure. For CHDE, climate, population, and their synergistic effects contribute about 75%, 20%, and 5% to the exposure, respectively. For CHHE, the contributions of these three factors are 85%, 10%, and 5% respectively. These findings provide scientific guidance for the rational formulation of population policies, the effective avoidance of climate disaster risks and the protection of human health. • Frequency of hot-dry events and hot-humidity events will increase and decrease, respectively, in the future. • There are abrupt points and periodicity in the future time series of compound temperature and precipitation extremes. • Asia is projected to have the greatest exposure and climate change contributes the most to exposure. [ABSTRACT FROM AUTHOR]

Computationally inexpensive carbon cycle models serve as critical and efficient tools for illuminating the complex dynamics of the carbon cycle and its interplay with the climate system, offering insights into how our planet has responded to climate perturbations throughout its history. During geologic hyperthermal events, carbon cycle models are employed to trace the trajectory of carbon emissions and establish a connection between the emission trajectory and changes in the Earth's surface environment. To date, the prevalent method to estimate the carbon emission rate relies on coupling the carbon cycle modeling and proxy reconstructions. Most previous studies employ a forward methodology, i.e., they force the model with an array of predefined carbon injection scenarios and select the one that produces the best fit to one or more specific proxy-derived records (e.g., atmospheric pCO 2 , sea surface pH, and calcite compensation depth) as the optimal solution. However, this forward method has two potential disadvantages. First, it can be computationally expensive, particularly when tens of thousands of scenarios need to be conducted to find the best solution. Second, it might not yield the best injection trajectory if none of the predefined carbon emission curves represents the realistic emission curve. Hence, an inverse model that can reconstruct the carbon emission trajectory directly from the record/records is urgently needed. In this study, building upon the Long-term Ocean-atmosphere-Sediment CArbon cycle Reservoir (LOSCAR) Model (Zeebe, 2012), we develop an interactive carbon cycle model (named iLOSCAR) using the open-source Python language and include two options, a forward model and an inverse model. The forward model replicates the original LOSCAR model, while the inverse model calculates the emission trajectory constrained by the proxy records in a single run. Both models are accessible via a web-based interface, which allows users to interactively tune model parameters and conduct experiments. In this paper, we present the details of iLOSCAR, including model structure and derivation of key equations. We then validate iLOSCAR's performance through an identical twin test and model intercomparison. We also apply it to a climatic perturbation event to diagnose features of the emission pattern that were overlooked in previous studies. Finally, we discuss the possible directions for model's future development. • The iLOSCAR model, an extension of the classical LOSCAR model, is introduced. • The model is capable of replicating the forward mode from the original LOSCAR model. • The model can derive reliable reconstructions of carbon emission trajectories inversely from proxy records for the geologic hyperthermal events. • The model features an interactive web interface, enabling users to dynamically adjust parameters and conduct scenario-based experiments. [ABSTRACT FROM AUTHOR]

This paper increases by around 30% the sample of atoll reef islands studied from a shoreline change perspective, and covers an under-studied geographical area, i.e. the French Tuamotu Archipelago. It brings new irrefutable evidences on the persistence of reef islands over the last decades, as 77% of the 111 study islands exhibited areal stability while 15% and 8% showed expansion and contraction, respectively. This paper also addresses a key research gap by interpreting the major local drivers controlling recent shoreline and island change, i.e. tropical cyclones and seasonal swells, sediment supply by coral reefs and human activities. The 1983 tropical cyclones had contrasting impacts, depending on the shoreline indicator considered. While they generally caused a marked retreat of the stability line, the base of the beach advanced at some locations, as a result of either sediment reworking or fresh sediment inputs. The post-cyclone fair weather period was characterised by reversed trends indicating island morphological readjustment. Cyclonic waves contributed to island upwards growth, which reached up to 1 m in places, through the transfer of sediments up onto the island surface. However, the steep outer slopes of atolls limited sediment transfers to the reef flat and island system. We found that 57% of the study islands are disturbed by human activities, including ‘rural’ and uninhabited islands. Twenty-six percent of these islands have lost the capacity to respond to ocean-climate related pressures, including the ‘capital’ islands concentrating atolls' population, infrastructures and economic activities, which is preoccupying under climate change. [ABSTRACT FROM AUTHOR]

This paper contributes to recent studies exploring the longue durée of human impacts on island landscapes, the impacts of climate and other environmental changes on human communities, and the interaction of human societies and their environments at different spatial and temporal scales. In particular, the paper addresses Iceland during the medieval period (with a secondary, comparative focus on Norse Greenland) and discusses episodes where environmental and climatic changes have appeared to cross key thresholds for agricultural productivity. The paper draws upon international, interdisciplinary research in the North Atlantic region led by the North Atlantic Biocultural Organization (NABO) and the Nordic Network for Interdisciplinary Environmental Studies (NIES) in the Circumpolar Networks program of the Integrated History and Future of People on Earth (IHOPE). By interlinking analyses of historically grounded literature with archaeological studies and environmental science, valuable new perspectives can emerge on how these past societies may have understood and coped with such impacts. As climate and other environmental changes do not operate in isolation, vulnerabilities created by socioeconomic factors also beg consideration. The paper illustrates the benefits of an integrated environmental-studies approach that draws on data, methodologies and analytical tools of environmental humanities, social sciences, and geosciences to better understand long-term human ecodynamics and changing human-landscape-environment interactions through time. One key goal is to apply previously unused data and concerted expertise to illuminate human responses to past changes; a secondary aim is to consider how lessons derived from these cases may be applicable to environmental threats and socioecological risks in the future, especially as understood in light of the New Human Condition, the concept transposed from Hannah Arendt's influential framing of the human condition that is foregrounded in the present special issue. This conception admits human agency's role in altering the conditions for life on earth, in large measure negatively, while acknowledging the potential of this self-same agency, if effectively harnessed and properly directed, to sustain essential planetary conditions through a salutary transformation of human perception, understanding and remedial action. The paper concludes that more long-term historical analyses of cultures and environments need to be undertaken at various scales. Past cases do not offer perfect analogues for the future, but they can contribute to a better understanding of how resilience and vulnerability occur, as well as how they may be compromised or mitigated. [ABSTRACT FROM AUTHOR]

The New Human Condition (NHC) is perhaps the largest cognitive challenge in history to human intelligence and agency and concerns our species' ability to cope with the consequences and responsibilities of being the major driver of planetary change in the twenty-first century ( Pálsson et al., 2013; Holm et al., 2015 ). But despite long held assumptions about intra-disciplinary engagements between its “human” and “physical” branches, geography's weakness as a discipline is that it has yet to gather sufficient momentum to collectively shape and implement practical and sustainable climate change policies and actions (Castree, 2014a). However, by considering together the heuristic values of the concepts of the Anthropocene and Planetary Boundaries, the Anglo-American sphere of geography recognizes in either ironic, or unconscious manners that a new strand of environmental determinism (discredited by geographical thought and practice in the early twentieth century) has re-emerged to elide the role of human agency and broadly dominate the discussion of climate change. Mike Hulme (2011, 247) states that “climate determinism” is “a form of analysis and prediction in which climate is first extracted from the matrix of interdependencies that shape human life within the physical world”. Within this discourse it is often the biophysical sphere that is employed to explain the course of human behavior; consequently, this dominating perspective threatens to skew our predictions and understandings of future societies, cultures, climates and destinies. Climate change will certainly constrain human agency, but it also creates the potential for geography to play to its intra and inter disciplinary strengths and begin discussing and addressing human-environmental dilemmas in practical and realistic ways; and secondly, seize the climate change crisis as an opportunity to study where, why and for whom global environmental change matters. Firstly, this paper considers a theoretical balance between the NHC, the Anthropocene and Planetary Boundaries as a way forward for geography to begin addressing the common dilemma of climate change. Within this consideration it engages Anne Buttimer's geographical translation of Martin Heidegger's lebenswelt as a dimension of the NHC. Secondly, the paper discusses how GeoHumanities and GIScience integrations with phenomenology, the digital and environmental humanities and social media generated “Big-Data” can explore the perceptual scales and scopes of the NHC/Anthropocene/Planetary Boundaries conceptual triad. Lastly, it argues that such integrations are salient to the study of emerging Smart City Lifeworlds as a means to engage the increasing urban agencies of global climate change driven by the vagaries of the human condition. [ABSTRACT FROM AUTHOR]

In light of the dilemma of global climate change that we have presented ourselves with in the twenty-first century and beyond, many researchers express despair at the ability of humans and societies to change behavior. The paper identifies how global humanity at individual, institutional, and governmental levels have addressed life-threatening dangers in the recent past and begun processes of long-term corrective action. The paper thus discusses global social transformations from the recent past in regards to tobacco use and HIV/AIDS, to think about how Hannah Arendt's concept of the Polis detailed in The Human Condition (1958) may be engaged to address the human dimensions of climate change. As an output of the Andrew W. Mellon European Observatory of the New Human Condition, this paper's focus is commensurate with the thrust of this special issue of Global and Planetary Change which considers climate change to be more of a crisis in the human condition than an environmental problem. Arendt's concept of the Polis provides a framework for a better understanding of change in behavior, preference and motivation. We argue that her perspectives are central to developing multi and inter-disciplinary humanities, social science, science and business perspectives to mobilize collective human action towards adapting to and mitigating the social and environmental threats of global climate change. [ABSTRACT FROM AUTHOR]

In recent years, studies have found that drought can occur rapidly under anomalous atmospheric circulation patterns and underlying surface conditions. This type of drought is defined as "flash drought". It is more sensitive to global warming compared to traditional drought and may become a common drought phenomenon in the future and require intensive research. But the characteristics and development mechanism of flash drought in northern China has been studied much less than in southern China, and thus deserve further study. Based on the daily station data and GLDAS grid data from 1978 to 2020, this paper identified the flash drought in northern China, analyzed its evolution of temporal-spatial characteristics and explored the meteorological driving factors of flash drought. The main results are as follows: (1)The frequency of flash drought in the year is the highest in WNW (West of Northwest), followed by ENW (East of Northwest), NC (North China) and NE (Northeast China), while the frequency in the plant growing season is the highest in the south of NE and the south of NC, and low in the other regions. (2)The hotspot areas of flash drought showed an obvious eastward trend from WNW to ENW in northern China from the 1980s to 2010s. (3) There is a good relationship between soil moisture and precipitation in WNW and ENW, while the soil moisture is affected by both temperature and precipitation in NC and NE. (4) Flash drought could occur all through the year in WNW and NC, while it mainly occurred in the summer half-year and summer in EWN and NE. The main high occurrence period of flash drought in each region is in late spring and early summer, while a second high occurrence period appears from early September to late October in WNW. (5) From the perspective of the driving of water vapor changes, the flash drought in WNW and ENW is mainly driven by water vapor advection, while that in NC and NE is mainly driven by wind field divergence. • The hotspot areas of flash drought showed an obvious eastward movement from WNW to ENW in northern China. • The main high occurrence period is around early May to early July in northern China, with a second one in WNW. • Flash drought in WNW and ENW (NC and NE) is mainly driven by water vapor advection (wind field divergence). [ABSTRACT FROM AUTHOR]

This paper briefly reviews the physical and human geography of the Kamchatka region and summarises previous research on Holocene climate dynamics. We provide context for the rest of the Special Issue of the Journal Global and Planetary Change entitled ‘Holocene climate change in Kamchatka’, the primary focus of which is the use of lake sediment records for palaeoclimatic inferences. In this paper an additional perspective from ongoing tree ring, ice core and borehole temperature reconstructions illustrates that the Kamchatka region is rich in paleoclimatic proxies. The period of the last 200 years is sufficiently covered by the proxy information, including reconstructions with annual resolution. In this period the tree-rings, ice cores, boreholes, and glacier fluctuations recorded a 1 °C warming and a general glacier retreat, i.e. the transition from the Little Ice Age climate to the modern one. Although the proxies have different resolution, accuracy and seasonality in general they demonstrate a coherent picture of environmental changes in the last two centuries. The tree ring and ice core records are up to four-six hundred years long and they provide information on annual to decadal variability of summer temperature, accumulation processes, volcanic eruptions and lahar activity. [ABSTRACT FROM AUTHOR]

The role of the land surface in climate and weather has been a major research focus since the 1970s. Since that time our understanding of the issue has greatly changed and many new themes in several disciplines are being considered. This article summarizes the changes in our understanding that have taken place in research on this topic and reviews principally papers that have appeared in the last two decades. Several other papers provide comprehensive reviews of literature that appeared prior to that time. The major changes that have occurred include 1) more sophisticated and rigorous analysis of desertification, 2) increased emphasis on hydrological processes, including the role of groundwater, 3) use of multi-model ensembles and regional models, 4) the emergence of the domain of ecohydrology, with emphasis on detailed feedbacks between water availability and vegetation, 5) examination of the hypothesis that vegetation feedback can produce abrupt climate change, 6) emphasis on the impacts on convective or synoptic-scale systems, and 7) consideration of the impact of aerosols, including the Saharan Air Layer. With the exception of desertification, each of these topics is reviewed. [ABSTRACT FROM AUTHOR]

This special issue deals with Extreme environments and biotic responses during the Neoproterozoic-Phanerozoic transition and comprises 23 papers. In this preface, we summarise the major findings and place them in a wider context. Some key discoveries are as follows: (1) After the Marinoan global glaciation (end-Cryogenian), a rise in seawater carbon isotopic composition of dissolved inorganic carbon (δ13C DIC), together with various biomarkers, indicate an increase in marine primary productivity, and imply a postglacial increase in atmospheric O 2 level by 3.8 13.4% of present atmospheric levels. (2) The earliest Cambrian sulfidic ocean was characterized by widespread but low levels of microbial sulfate reduction (MSR) in seawater with active microbial iron reduction in sediment porewaters; this state differs from present day sulfidic water masses, such as those in the Black Sea, which show predominantly MSR in the sediment. Multiple geochemical proxies demonstrate that a dynamic 'euxinic wedge' may have existed at mid-water depths, and its expansion/contraction controlled redox variations during the early Cambrian. (3) Studies of Hg concentration and isotope analyses shed new light on the Late Ordovician mass extinction event, and reveal that volatile volcanism probably acted as a trigger for several catastrophes, involving climate change, ocean acidification, and anoxia. (4) Other findings show that primitive foraminiferans may have occurred already prior to the Cambrian Explosion, brachiopod-dominated shell beds were already present in the early Cambrian, and reef-builders diversified during the Middle Ordovician, altering our understanding of Cambrian-Ordovician evolution. The papers in this special issue therefore improve knowledge of the Neoproterozoic-Phanerozoic transition and will be of interest to a broad readership of palaeontologists and earth system scientists. • The virtual special issue on the Neoproterozoic-Phanerozoic transition is timely and will attract the growing research interest. • The set of papers assembled in this VSI offers some stimulating suggestions on future studies on these topics. [ABSTRACT FROM AUTHOR]

The oceanic influence on winter precipitation in the Iberian Peninsula has been evidenced in numerous scientific papers. Large-scale forecasting models generally use variables such as Sea Surface Temperature (SST), soil moisture and ice cover, but they are not very accurate yet. Using observational data, this paper analyzes the influence of North Atlantic and Mediterranean SST on winter precipitation in the Iberian Peninsula between October 1951 and September 2011. First, trends of both data sets have been calculated to study their behavior during the past six decades, showing an overall increase of SST and a substantial decrease in winter precipitation in the Iberian Peninsula, except in eastern and south-eastern regions. Then, connection patterns between autumn Sea Surface Temperature Anomalies and winter precipitation have been studied to identify ocean regions that may be used as potential predictors of winter precipitation. After applying a Principal Component Analysis to cluster the information provided by the 1431 measuring points of a SST grid with a small number of variables, the Principal Components extracted were introduced into a Multiple Linear Regression algorithm in order to obtain an estimation of winter precipitation in each river basin. The validation process has shown that the algorithm explains nearly 50% of inter-annual variability of winter precipitation in the basins of the Iberian Peninsula with a strongly oceanic influence; this percentage is somewhat lower in the Mediterranean regions. [ABSTRACT FROM AUTHOR]

The paper concerns ice dams and glacial lake outburst floods (GLOFs) in the Karakoram. Some 146 events are identified, including 30 major disasters. Large downstream populations and major infrastructure are threatened. Risk factors differ from recent reports of other Himalayan GLOFs associated with glacier recession and global warming. Ice dams are largely or entirely active ice, put in place by advancing glaciers. Climate change is a factor, but the ice cover in the Karakoram has been sustained, and even some increase in mass. Surge-type glaciers comprise or affect~70% of our inventory. The most frequent, large GLOFs come from local clusters of glaciers in five sub-basins, given special attention here. In four there were new ice dams formed since 2008 and two generated dangerous GLOFs. An urgent need arises to track short-term ice and lake behavior and how surge dynamics may be involved. Satellite images and DEMs are employed in cross-correlation feature tracking and elevation change respectively. The glaciers of interest all exhibit irregular movement, including recent advances, but with great variability and no clear relation to climatic fluctuations. • Study updates inventory of ice dams and related GLOFs in the Karakoram. • Study reports recent evidence of surface displacement and elevation changes of glaciers involved in ice dam generation. • Surge-type glaciers comprise or affect ~70% of inventory of ice dams and related GLOFs. • Four glaciers formed new ice dams since 2008, two (Kyagar, Khurdopin) generating dangerous GLOFs. • The studied glaciers exhibit irregular movement, but with great variability and no clear relation to climatic fluctuations. [ABSTRACT FROM AUTHOR]

Studies on long-term fluctuations in glacier volume and mass are crucial for understanding past climate change. In this paper, we utilized Picea schrenkiana to develop a 525-year chronology of latewood blue intensity (LWBI) in the Tianshan Mountains. Relying on temperature as the main controlling factor for tree growth and glacier mass balance (GMB) variations, the LWBI chronology was used to reconstruct the summer temperature (JJA, R 2 adj = 47%) and the annual glacier mass balance (annual GMB, R 2 adj = 39%) in the Tianshan Mountains over the past 400 years. The reconstruction results show that the rapid warming since 1974 has caused the Tianshan No.1 glacier (TS No.1) to experience an unprecedented melting trend within the last four centuries. It is disturbing that the glacier still remain in an ablation state for the next 80 years under both representative concentration paths (RCP) 4.5 and 8.5 scenarios, which will exacerbate the adverse environmental impacts of glacial hazards. Our study provides a continuous record for glacier research in high mountains Asian and contributes to a more detailed assessment of glacier and climate change in this region. The spatial correlation analysis of the PC1 and the ERA5 grid temperature dataset after the original (a), detrended (b) and first-order difference (c) calculations in the verification period (1950–2005), all insignificant correlations (P > 0.05) were masked out, where A represent the Tianshan Mountains (this study), B represent Central Europe Alps (Büntgen et al., 2006), C represent East Asia (Davi et al., 2002), D represent Dunde ice core (Thompson et al., 2006), and E represent Guliya ice core (Thompson et al., 1997). Comparison of Tianshan temperature reconstruction (PC1) with other MXD-based temperature reconstructions, where (d) is the comparison between PC1 and Central European Alps summer (June to September) temperature reconstruction, (e) is the comparison between PC1 and East Asian Japanese warm season (May to September) temperature reconstruction, and (f) is the comparison between PC1 and Northern Hemisphere summer (June to August) temperature reconstruction (Schneider et al., 2015). (g) is the comparative between the PC1 and Atlantic multidecadal variability (AMV, Wang et al., 2017). Comparison of TS No.1 GMB reconstruction with ice core accumulation data, where (h) is the comparison between TS No.1 GMB reconstruction and Dunde ice core water equivalent net balance (accumulation, 5-year average), (i) is the comparison between TS No.1 GMB reconstruction and Guliya ice core water equivalent net balance (accumulation, 10-year average). All comparison series are Z-score normalized and low-pass filtered with a step size of 10 years (ice core accumulation data are 5 year) to achieve low-frequency fluctuations. [Display omitted] • A 525-year latewood blue intensity (LWBI) chronology was developed to study glacial dynamics for the Tianshan Mountains. • The results showed that the last 20 years to be outside the range of natural variability of the last 400 years. • The Tianshan No. 1 glacier will continue to melt rapidly in the next 80 years under the RCP 4.5 and 8.5 scenarios. [ABSTRACT FROM AUTHOR]

Machine learning is increasingly used to study vegetation growth, however, more often than not, predicting and simulating functions are prioritized over quantitative estimates of the drivers of vegetation growth such as climate. In this paper, we, for the first time, systematically investigate the model bias in calculating factor importance of climate on vegetation growth, especially when various kinds of machine learning models are considered. We undertake two case studies to simulate research in remote sensing and ground-based scenarios from which the difference in quantitative relationships between climate and vegetation is evaluated across multiple models. We found that model complexity increased the determination coefficient (R2) but reduced the absolute importance of the preselected independent variables. As the fitting accuracy increases, the absolute factor importance of dominant factor and all the other influencing factors decreases simultaneously, and factor importance calculated by different models tended to be more normally distributed across the study region. The reduction in factor importance was accompanied by the increased effect of model selection; e.g. the model that was used to estimate vegetation growth played a larger role in producing the factor importance (shown by variance analysis, remote sensing scenario, F-statistic = 555.2; ground based scenario, F-statistic = 30.8) than the climate variables (variance analysis, remote sensing scenario, F = 460.8; ground based scenario, F = 28.8). Critically, for those machine learning models with highest fitting accuracy, the resultant factor importance of climate factors had smaller difference with that of random factor. In contrast, the relative factor influence among the selected climate factor is more robust and reliable (in variation analysis, model was detected no significant impact on the resultant factor importance). For 5 of 8 models, the dominant factor (temperature) has relative influence over 0.85, ranging from 0.88 to 0.99. According to the relevant result, we suggest testing the stability of factor contribution in future studies, particularly when using machine learning models in ecological research and dealing with numerous factors, before drawing relative conclusions. The balance between simple and accurate models is contested and we believe that our study will contribute to a better understand of the data behind this debate. • The selection of machine learning models has overwhelmed the environmental factors in calculating factor importance on global vegetation growth. • With more complexity of machine learning models, factor importance of all influencing factors on vegetation growth decreases simultaneously. [ABSTRACT FROM AUTHOR]

Provenance analyses provide valuable insights into both the complex interaction between orogenic belts and surrounding sedimentary basins and the role of plate collision in the basin-mountain coupling process. This paper investigates the provenance of the Cenozoic sediments filling the Qaidam Basin (Qinghai Tibetan Plateau, China) by combining petrology, major elements, trace elements, rare earth elements (REEs), and Zircon U Pb dating analysis to provide new insight about the collision of the Indian and Asian plates. The petrographic analysis indicates that the studied sediments are poorly sorted and made of angular to subrounded clasts, suggesting deposition relatively near to the source area. The Chemical Index of Alteration (CIA) of the samples in the study area, which ranges from 68.88 to 74.08, indicates that the study area experienced moderate weathering from the early Eocene to the early Miocene. In addition, Zr/Sc versus Th/Sc shows that most samples did not experience recycling. K 2 O/Na 2 O, SiO 2 , Th, Sc, Zr, La and Co contents indicate that the Cenozoic sediments filling the Qaidam Basin derived mainly from an active continental margin and a continental island arc setting. U Pb dating of detrital zircons denotes that the studied sediments were derived from rocks with five major sets of ages (200–350 Ma, 350–500 Ma, 500–1000 Ma, 1000–1500 Ma, and >1500 Ma), with the two first sets being more common. Based on the regional geology, therefore, these ages indicate that the main provenance source was shifted southwards from the Mesozoic crystalline basement (south Qilian Mountains) in the early-middle Eocene, to the Saishiteng Mountains in the middle-late Eocene, and to Lvliang and Qilian Mountains during the late Eocene-early Miocene. Zircon dating also indicates that the main source area was displaced eastward through time. Finally, it is concluded that the tectonic deformation progressed from west to east in the northern margin of the Qaidam Basin, reflecting a far-field response to the onset of the India-Asia collision. • The sediments mainly derive from source terranes that used to be active continental margin and continental island arc. • Detrital zircon evidence indicates that the Qilian Mountains, instead of the East Kunlun, were the dominant detrital source. • The tectonic deformation during the early Eocene reflected a far-field response to the onset of India-Asia collision. [ABSTRACT FROM AUTHOR]

Abstract: Knowledge of the Little Ice Age (LIA) on the Tibetan Plateau (TP) is of critical importance for understanding the climate changes over the past millennium. However, the data associated with the extents and chronologies of TP LIA moraines are highly dispersed in literature. Lack of systematic integration of these data hampers us to further understand the nature of the LIA, especially from a perspective of whole TP. The paper reviews multiple types of dating on LIA moraines to examine the timing and nature of the LIA on the TP. These include ages of radiocarbon 14C, lichenometry, and cosmogenic radionuclide (CRN), by which we can cross-date the same or morphostratigraphically similar landforms. LIA moraines on the TP are usually present a few hundred to thousand meters beyond the contemporary glaciers. The morphological and stratigraphic evidence indicates multiple periods of glacier advance during the last millennium (LIA). At present, available chronology evidence allows to fully compare the timing of the LIA maximum extents. The glaciers reached and retreated from their LIA maximum extents by an asynchronous pattern between different parts of the TP. The majority of glaciers advanced to their LIA maximum extents at late-14th and early-14th century on the southern and northwestern TP, respectively. The glaciers retreated from their LIA maximum extents during 16th to early-18th, late-14th to early-15th and early-16th century on the southern, northwestern, and northeastern TP, respectively. In addition, the glacier advance period of late-18th to early-19th centuries and retreat period of late-19th century are common on the whole TP. Comparison with ice core records suggests that on the TP, the glacier fluctuations responded more strongly to temperature than to precipitation. By comparison of the LIA chronologies from a global perspective, this paper also concludes that the LIA maximum extents occurred commonly earlier on the TP than in North Atlantic and Southern Hemisphere regions, despite of the variability in the timing of LIA maximum extents on the TP and in the North Atlantic regions. Further, more chronology programs, especially in the central TP, are necessarily needed to improve our understanding of the LIA glacier fluctuations. [Copyright &y& Elsevier]

Abstract: High-resolution environmental proxy data from the extratropical North Atlantic prior to the instrumental era are of critical importance to decipher processes and mechanisms of global change. In this regard, shells of the extremely long-lived bivalve mollusc, Arctica islandica (Linnaeus, 1767), have gained particular attention during the last decade because they serve as reliable, subseasonally resolved multi-proxy archives of environmental variability in that very region. With a lifespan of more than 500years, A. islandica is the longest-lived solitary animal. Its shell grows periodically throughout life and contains distinct annual and daily growth increments. These growth patterns function as a calendar that can be used to place each shell portion into a precise temporal context. Furthermore, changing environmental conditions are encoded in the shells in the form of variable increment widths and geochemical properties. By means of cross-dating, growth increment width chronologies from different specimens can be combined into much longer time-series, so-called composite or master chronologies, covering centuries to millennia and many generations of bivalves. The present paper provides a comprehensive review of research on this species with a special focus on long-term climate and environmental reconstructions using isotopes, trace and minor elements and variations in shell growth. This review also highlights challenges involved with the interpretation of proxy data obtained from A. islandica and identifies future research needs. A. islandica does not easily reveal its secrets. It needs a holistic approach to unlock the multi-proxy records stored in their shells. The goal of this paper is to increase the recognition of this high-potential natural archive and encourage future interdisciplinary research. [Copyright &y& Elsevier]

Abstract: The fluvial network of the Southern Pyrenees is an example of transverse drainage systems in young (alpine) mountain belts and it features well preserved fluvial terrace records. Some of the major Southern Pyrenees tributary rivers have been studied previously and have some age controls on their fluvial terrace levels. We extend these records to one of the largest streams in the Southern Pyrenees, the Segre River. In this paper, we present new GIS data, field observations and exposure ages obtained from in situ produced terrestrial cosmogenic nuclides (10Be). The focus of this paper is set to unravel the relative impact of climatic controls on the formation of the Segre terrace staircase in the Southern Pyrenees foreland (Ebro Basin). The Pleistocene terrace staircase of the Segre River is built up by seven major terrace levels, which range from 112 to 3m above the present-day active channel. The prominent upper and middle terraces TQ1, TQ2, TQ3 and TQ4 have been sampled for 10Be exposure dating. Exposure ages have been calculated using Monte Carlo parameter simulations. Additionally, we applied a Profile Rejuvenation method accounting for variable 10Be inheritance in the samples, and which yielded comparable results. The Monte Carlo results show Middle to Late Pleistocene exposure ages for TQ1: 202ka (MIS 7), TQ2: 139ka (MIS 6), TQ3: 100ka (MIS 5), and TQ4: 62ka (MIS 4), involving denudation rates of 3–8mmka−1. The results indicate that the abandonment of Segre paleo-floodplains and the change from aggradation to predominant incision is related with Middle to Late Pleistocene cold-warm climate transitions (or early stages of interglacial periods). Major floodplain aggradation appears to be linked with intense deglaciation at the end of MIS 8, MIS 6, and MIS 4. The exposure of terrace TQ3 (MIS 5) indicates that terrace formation might also occur during relatively warm isotope stages with sufficient climate instability. On a regional scale, the staircase morphology at the Segre River shows similarities with adjacent fluvial systems in the Southern Pyrenees. In addition, previously published chronologies for these systems are consistent with the timing of aggradation and terrace abandonment. Both, staircase morphology and chronology point to regionally synchronous phases of floodplain aggradation and river incision, which seem to be triggered by climate variability and Pleistocene glaciations in the Pyrenees since the Mid Pleistocene Climatic Revolution. [Copyright &y& Elsevier]

Abstract: Since two decades ago, when China''s economic strength has made this most populated country as a leading global agricultural outsourcer, there have increasingly been hot debates on whether such outsourcing is destructive or constructive, especially for host countries. Some critics pessimistically call it ‘land grabs’ or ‘neo-colonialism’ that should be prevented while others optimistically appreciate it as a development opportunity that should be promoted. The first group interprets the outsourcing as a win–loss process while the second considers it as a win–win deal. This study tries to show the possible gains and losses of both outsourcers and host countries. Accordingly, this paper introduces four different situations; i.e. loss–loss; win–loss; loss–win; and win–win. The first situation is understood as a ‘red-deal’ which should urgently be stopped. The second and third situations are called ‘yellow-deal’ which should be adjusted to come up with the last situation which we call ‘green-deal’ that addresses the benefits of both outsourcers and outsourcees. The paper concludes that in order to understand the main impacts of such deals, we still need to create more evidence for each situation in the framework of a series of risk assessment studies on the bases of both “country-case” and “crop-case”. [Copyright &y& Elsevier]

Abstract: The Murray–Darling Basin is Australia''s food bowl and home to many iconic water bodies that are culturally and ecologically highly valued. The recent Millennium Drought (from mid-1990s to 2009) was the most severe hydrological drought since records started in the late 19th century. It severely impacted on the basin and for many acted as a wake-up call. To address the ongoing declines in water resources and environmental conditions and to prepare the region for climate change, Australia''s Governments are currently attempting to introduce a new comprehensive, and integrated approach to the management of the basin''s water resources. In this paper, long-term time series of climate, hydrological and environmental data are used to analyze how compounding stresses have gradually affected the hydrological system and its services. Major hydroclimatic stresses considered in this paper include salinity, water use, droughts, and climate change. Other, more localized or minor stresses exist (groundwater extraction, farm dams, afforestation, bush fires, cyanobacterial blooms and pollutants) and are reviewed more briefly. The history of water policy and planning shows that Government actions have been strongly influential on the basin. A shift in the strategic goals from water development to the protection and restoration of environmental assets is noticeable since the mid 1990s. Median climate change projections by 2030 indicate smaller reductions in rainfall and runoff than those observed during the recent Millennium Drought, but have a relatively high uncertainty attached to them. The use of regional approaches to reduce that uncertainty, such as statistical downscaling, points to a sizeable decline in rainfall by the end of the century. Most climate projections used for planning consider greenhouse emission scenarios that have smaller global emission trends than the one observed over the last decade. Other, ‘less optimistic’ scenarios have to be considered for long-term water planning and food security. Compounding all these stresses, is the naturally high hydroclimatic variability of this semi-arid region, that may have been insufficiently considered during previous water development and planning efforts. Successful water planning will need to balance cultural and ecological values with food production, account for high natural variability and uncertainty in climate change projections, learn from past mistakes and be cognizant of future hydrological changes. [Copyright &y& Elsevier]

As reported in previous studies, global warming has caused a clear uptick in dryland areas since the 1950s. Meanwhile, the accelerated expansion of drylands has become particularly evident over the past 40 years, with dry/wet patterns showing significant differences prior to and after 1980. This paper uses the Precipitation/Potential evaporation (P/PET) index to analyze changes occurring in the dry/wet structure of various spatial and temporal scales during 1948–2008. The results show the emergence of complex aridity changes on a regional scale. While aridity generally decreased in the drylands of Asia during 1948–2008, the change in aridity was opposite in the drylands of the American and African continents between 1948 and 1979 and 1980–2008. Specifically, drylands in the American continent showed a wetting tendency during 1948–1979 and a drying tendency during 1980–2008, whereas drylands in the African continent underwent significant drying during 1948–1979 followed by subtle wetting in 1980–2008. Even though rapid warming since the 1980s has become an increasingly important cause of the recent global drying trend, especially in East and Central Asia, the changes in aridity in the American and African drylands is attributable to natural variabilities in precipitation associated with multi-decadal surface sea temperature changes, along with large-scale circulation patterns. • Dry/wet patterns in dryland areas show significant differences in the decades prior to and after 1980. • The change in aridity was opposite in American and African drylands between 1948–1979 and 1980–2008. • Aridity changes in American and African drylands are closely related to multi-decadal changes in surface sea temperature. [ABSTRACT FROM AUTHOR]

Mountain lakes are often situated in protected natural areas, a feature that leads to their role as sentinels of global environmental change. Despite variations in latitude, mountain lakes share many features, including their location in catchments with steep topographic gradients, cold temperatures, high incident solar and ultraviolet radiation (UVR), and prolonged ice and snow cover. These characteristics, in turn, affect mountain lake ecosystem structure, diversity, and productivity. The lakes themselves are mostly small, and up until recently, have been characterized as oligotrophic. This paper provides a review and update of the growing body of research that shows that sediments in remote mountain lakes archive regional and global environmental changes, including those linked to climate change, altered biogeochemical cycles, and changes in dust composition and deposition, atmospheric fertilization, and biological manipulations. These archives provide an important record of global environmental change that pre-dates typical monitoring windows. Paleolimnological research at strategically selected lakes has increased our knowledge of interactions among multiple stressors and their synergistic effects on lake systems. Lakes from transects across steep climate (i.e., temperature and effective moisture) gradients in mountain regions show how environmental change alters lakes in close proximity, but at differing climate starting points. Such research in particular highlights the impacts of melting glaciers on mountain lakes. The addition of new proxies, including DNA-based techniques and advanced stable isotopic analyses, provides a gateway to addressing novel research questions about global environmental change. Recent advances in remote sensing and continuous, high-frequency, limnological measurements will improve spatial and temporal resolution and help to add records to spatial gaps including tropical and southern latitudes. Mountain lake records provide a unique opportunity for global scale assessments that provide knowledge necessary to protect the Earth system. • Mountain lakes are sensitive recorders of global environmental change. • Paleolimnology has benefited from technological advances, with many applications to alpine environments. • Gaps in spatial coverage are evident in the tropics and Southern Hemisphere, where water resource issues are a concern. • Paleolimnology can be used to identify threats to the quantity and quality of mountain reservoirs. • We highlight the complexities of ecosystem responses to the many, interconnected stressors of global environmental change. [ABSTRACT FROM AUTHOR]

The Qinling Mountains (QLM) form the climatic boundary between the temperate north and subtropical south of China. Many important Paleolithic archaeological sites located on fluvial terraces in this area have been reported in recent decades. Abundant artifacts have been excavated in silt layers overlying fluvial gravels and coarse sands. These silt layers have thus far been interpreted as aeolian deposits. However, in principle they could also represent (in part) fluvial (floodplain) deposits, especially near the base of fine-grained sequences. Reconstruction of fluvial terrace formation is crucial for the correct interpretation of the environment of hominin occupation. In this paper, two sediment sequences from two Paleolithic sites, located on different terrace levels of the Hanjiang River in the Hanzhong basin, are studied mainly using grain-size and grain-shape analyses. In addition, grain-size distributions have been unraveled by applying end-member modelling to distinguish different sedimentary environments. The results show that three different units can be discriminated in each section. The lower unit, consisting of gravelly sand mixed with fine silt, is interpreted as shallow-channel-fill sediment deposited during the start of the transition from a channel to a floodplain environment. The middle unit comprises a fine-grained, gradually fining-upward sequence, representative a floodplain environment. At its base, it reflects a high-energy floodplain situation; at its top, the sequence is interpreted as a low-energy floodplain environment with aeolian input (settling in static water). The third, uppermost unit consists of aeolian loess interbedded with paleosol(s) and sediments that are interpreted as the results of episodic surface runoff. The gradual transition between the 3 units and the gradual fining upward trend of the middle unit indicates that there is no considerable age gap (no hiatus) between the fluvial- and aeolian sedimentary environments. Stone artifacts have been found in all 3 units, with difference abundance, indicating that both the aeolian and floodplain depositional environments provided favorable living conditions. For the floodplain environment, the resources of water and raw materials (fluvial gravels) for tool making may have offered fundamental resources for hominin settlement. • The depositional environments of the artifact-bearing sediment have been determined. • Both aeolian dust deposit on terrace surface and floodplain environment were occupied by hominins in central China. • The transition from fluvial to aeolian sedimentary environment during incision is gradual. • Combined grain size and grain shape analysis allows for the distinction of aeolian and fluvial sedimentary environments. [ABSTRACT FROM AUTHOR]

In this paper we tackle a problem of representative measuring points selection for temperature field reconstruction. This problem is a version of the more general Representative Selection (RS) problem, well-known in computer and data science. In this particular case, the objective is to select the best set of N measuring points (i.e. N representative points), in such a way that a reconstruction error is minimized when reconstructing the monthly average temperature field. We use a novel meta-heuristic algorithm, the Coral Reefs Optimization with Substrate Layer (CRO-SL), which is an evolutionary-type method able to combine several different search procedures within a single population. The CRO-SL is combined with the Analogue Method (AM) to identify the most representative points. This approach exhibits strong performance from experiments with gridded and un-gridded temperature field datasets (European Climate Assessment & Dataset (ECA) and ERA-Interim reanalysis (ERA)). Different aspects such as the error assessment and the comparison with alternative approaches, are discussed in the experimental analysis of this article. We show that the algorithm performs better than a greedy approach, i.e. the best solution for N points is different from the N best individual predictors. The solutions obtained with the proposed methodology are climatologically consistent and include points from Scandinavia, Central and Southern Europe, the Black Sea and Central and South Western Asia as the more representative in the case of the ECA dataset; similar areas are selected for ERA. We have found out that once the number of stations/points goes over a threshold, the improvement in the model is obtained by increasing the density of data in the given zones, instead of adding data from different zones to the algorithm. The method proposed may have direct application in Palaeoclimalogy, where there are a large amount of distributed proxies with scarce information, so the proposed approach could be useful to select the most important ones to reconstruct a desired field. • We solve a problem of representative measuring points selection for temperature field reconstruction. • The Analogue Method is used as reconstruction algorithm. • An evolutionary-type meta-heuristic is proposed to select the best set of representative points. • A reconstruction error for the temperature field is minimized by the algorithm. • Experiments in two monthly temperature datasets in Europe have shown the good performance of the algorithm. [ABSTRACT FROM AUTHOR]

Knowledge about changes of flood occurrence patterns is important for risk estimation of the future. Robust and well-calibrated paleoflood records, derived e.g. from lake sediments, are excellent natural archives to investigate flood variability of the past and to use the data for further modelling. In this paper, we analyse a 7100 year summer flood record recovered from Lake Mondsee (NE Alps), using a statistical approach. We identify a point process of renewal type, with a significant change-point of the occurrence pattern around 350 CE, switching from the overlay of two mechanisms of event recurrences of 5 and 50 years before to 2 and 17 years after this change-point. This change-point approach enables a comparison to other flood records, and possibly to relate event frequencies to climatic conditions. We also highlight how lower temporal resolution of flood records can hamper the analysis of relations to climatic signals. Hence high-resolution records with robust chronologies and flood information (e.g. seasonality and event characteristics) are essential to improve the understanding of the interplay between climatic signals and flood occurrences, which is an important ingredient for proper risk estimation and risk management. • Statistical properties of selected alpine paleoflood records • Change-point models are simple and powerful alternatives to describe the pattern of paleoflood records • Change-point for 7100 yr summer flood series from Lake Mondsee identified around 350 CE [ABSTRACT FROM AUTHOR]

Abstract The field of quantitative palaeoclimatology has made significant progress in the past decades. However, this progress has been spatially heterogeneous and strong discrepancies – both in terms of quality and density – exist between Europe and North America and the rest of the world. The need to balance this distribution of quantified records has never been stronger, and improving our understanding of past global climate is urgent in order to better evaluate and employ the predictions of climate models. In this paper, it is argued that this gap can be reduced by applying the climate reconstruction method CREST (Climate REconstruction SofTware) calibrated using the open-access GBIF (Global Biodiversity Information Facility) database, which contains hundreds of thousands modern distributions of numerous bio-indicator proxies (e.g. pollen, chironomids, foraminifers, etc.). Using the taxonomical diversity of the GBIF database, CREST can be used to reconstruct various climate and/or environmental parameters from assemblage variety of different records. Independent from the usual reconstruction techniques using surface samples for calibration, the CREST/GBIF framework can also be used as an independent tool that can be easily and efficiently applied (1) to complete the global coverage of climate reconstructions, as exemplified with a precipitation reconstruction from Lake Van, Turkey, (2) to revisit existing data sets to obtain new quantitative reconstructions, and (3) to evaluate and/or refine reconstructions based on other methods. The application of this tool promises to foster advances in our understanding of the past climate variability of the Earth system at a global scale. Highlights • A new, globally applicable probabilistic tool to quantitively reconstruct past climates. • The calibration dataset contains the distributions of multiple palaeoclimatic bio-indicators. • Understudied regions can now be explored using the CREST/GBIF framework. • A dedicated software exists to facilitate the use of the CREST/GBIF framework. [ABSTRACT FROM AUTHOR]

Abstract Vegetation-atmosphere interaction is thought to have significant impacts on modulating regional climate. The main purpose of this paper is to reveal the impact of vegetation change on regional climate simulation over Eastern China. Therefore, we have performed three 30-year simulations from 1982 to 2011 with the WRF model coupled with the Noah land surface model as follows: a control experiment with climatology green vegetation fraction (GVF) (CTL), a sensitive experiment with WRF default climatology GVF (CLMV), and a sensitive experiment with dynamic vegetation (DYNV). The climatology difference between the CTL and CLMV experiment points out that during 1982–2011 over Eastern China, the increase of vegetation causes the decrease of temperature; on the other hand, the increase of temperature often corresponds to the reduction of vegetation. In the meantime, the increase/decrease in GVF is quite consistent with the simulated increase/decrease in precipitation, which is caused by both circulations and water vapor distributions at lower levels. The difference in the temperature trend between the CTL and DYNV experiment is almost opposite to that between the DYNV and GVF trend, which means that the decreased/increased vegetation will increase/decrease the surface air temperature. However, the trend of precipitation variation shows no clear relation with that of GVF. In response to GVF change, the results show that in the vegetation-climate feedback the moisture feedback is dominant over the radiation and momentum feedback. Significant decrease in GVF and LAI is detected across the East China, which leads to the decrease in the latent heat flux and increase in the sensible heat flux. For extremes and heat waves, it is shown that DYNV leads to better stimulation on the maximum of daily maximum temperature (TXx), warm spell days (WSDI), heat wave days (HWNY) and the averaged heat wave duration (HWDU) than CTL does over most of the Southeast China, although it may introduce some new biases in the Eastern coastal regions as well as the Northeastern China. Highlights • Dynamic green vegetation fraction (GVF) data was used for simulation. • Studied the effect of vegetation variation on climate extremes. • The results are also compared with actual observations. [ABSTRACT FROM AUTHOR]

Abstract A high-resolution sedimentological and geochemical analysis of a 21 m sediment sequence of Lake Iseo (Southern Alps, Italy) allowed for the reconstruction of the long-term flood frequency by visual identification of the event layers over the last 12 kyr cal BP. In a previous study that was undertaken on another sediment core from Lake Iseo, these layers were attributed to extreme surface runoff events. However, in this former core, large mass-wasting deposits that induce significant hiatuses did not permit a continuous record of flood events to be established. Such disturbances were absent in the core studied in the present paper. This permitted to establish a high-resolution continuous Holocene record. Based on the flood chronicle and sedimentological and XRF geochemical analyses, we found evidence of a major palaeohydrological transition at approximately 3.8 kyr cal BP, which was previously described as occurring in the western Mediterranean region. The oldest part of the record indeed presents a very low frequency of flood events (<1 flood/century), while after 4 kyr cal BP, the flood frequency increased. This pattern appears to be in agreement with other Southern Alpine paleo flood records. The transition is interpreted as a nonlinear climate response to the orbital-driven gradual decrease in summer insolation at 60°N, which together with the influence of the Mediterranean mesoscale precipitation events, is typical for the Mediterranean climate. However, the comparison of the flood record with the archaeological and historical data from the watershed suggests that human activity during the Roman period in the vicinity of the main tributaries also influenced the flood frequency. Even in a large Alpine lake and >2000 years ago, extreme precipitation events that were recorded through the sedimentation process can hence be impacted by the anthropization of the catchment area pointing the requirement of deeper studies of Earth surface critical zone pluri-millennial dynamics. Highlights • In the Alps, flood frequency is higher during period of cold and wetter climate. • A major palaeohydrological transition is observed at approximately 4 kyr cal BP. • From 2 kyr cal BP, human activity is the main driver of the SEB10 flood frequency. • In Alpine lowland lake, flood chronicle can be impacted by the anthropization. • Studying human activity is needed for flood-paleohydrological reconstructions. [ABSTRACT FROM AUTHOR]

Abstract With increasing levels of atmospheric p CO 2 the oceans are becoming progressively more acidic, with the impact of a lowered pH beginning to affect the calcification of numerous invertebrate groups, including foraminifers, pteropods, heteropods and calcareous nannoplankton. Research on the ecology of foraminifera in the Mediterranean Sea, Gulf of California, Caribbean Sea and elsewhere has shown how modern assemblages are responding to acidification. Experimental work in mesocosms and laboratory cultures are also adding to our knowledge of the response to pH changes. Near Ischia (Italy), natural CO 2 vents amongst sea grass meadows are creating low pH environments in which it is possible to observe the response of benthic foraminifera. At a pH of 7.8 the foraminiferal assemblages are already becoming less diverse and below pH 7.6 there are often no calcite-secreting benthic foraminifera. In the Gulf of California, in a deeper-water setting, natural CO 2 (and methane) vents are also lowering sea floor pH. The foraminifera show the impact of this change, although the relatively high carbonate saturation ensures that calcite-secreting foraminifers are able to live and reproduce in these relatively low pH environments, only becoming impacted by dissolution effects once dead. Using data from the Cretaceous–Paleogene boundary in Texas, Alabama and north-west Europe it is clear that the plankton was severely impacted by surface water acidification while the relatively shallow water benthic foraminifera show little change and no visible signs of post-mortem dissolution due to ocean acidification. Highlights • This paper discusses the K/Pg in terms of surface water acidification caused by the K/Pg impact event. • describes depositional environments at K/Pg boundary • provides depositional model for the K/Pg boundary • provides correlaton of the boundary events [ABSTRACT FROM AUTHOR]

Abstract In their paper, Mujal et al. (2017) describe as exceptional a section in the E Pyrenees (namely the Coll de Terrers), considering it a continental succession that continuously spans in time from the Late Permian to the Early Triassic. These authors describe the sandy-clayey red-beds of the upper Buntsandstein unit as the upper part of the Upper Red Unit (URU) and provide substantial stratigraphic and sedimentological data as well as palaeontological and mineralogical data in support of their thesis. We firstly have to consider that the post-Variscan deformation events altered the sedimentary contacts among the units (i.e. subsidence and tectonic evolution of the related sub-basins); and secondly, that the entire succession contains several tectonic structures affecting the late Palaeozoic-early Mesozoic sequence, due to the Alpine orogeny. The purported stratigraphic continuity between the Permian and Triassic is thus hampered not only by a different sedimentological and stratigraphical content but also by a complex tectonic framework. Highlights • The Coll de Terrers section (E Pyrenees, Spain) is questioned as a continuous continental succession through the P and T; • The attribution of the Upper Red Unit to the Buntsandstein facies is discussed; • A prolonged hiatus occurs comprising the Middle?-Late Permian to the Early Triassic like in all successions of W Europe. [ABSTRACT FROM AUTHOR]

Abstract The effects of climate changes on biotic expansion or divergence is a widely debated topic. This discussion is particularly relevant for northern Amazonia where patches of open vegetation environments that harbor high endemic and specialized species are present in a matrix of tall closed canopy forest. This paper presents the depositional chronology and evolution of an 8.7-m thick stabilized fluvial and eolian sediment profile in a sandy plain substrate that underpins the largest open vegetation enclave in northern Amazonia. Three depositional units were identified using optically stimulated luminescence and radiocarbon ages coupled with grain size, magnetic susceptibility, and reflectance analyses. A lower unit of coarse fluvial silt deposited between 53 and 28 ka is overlain unconformably by a 5-m thick middle unit of fine eolian sand deposited at high accumulation rates between the Last Glacial Maximum (23–19 ka) and Heinrich Stadial 1 (HS1; 18.1–14.7 ka) when persistent and long-lasting shifts of the Intertropical Convergence Zone (ITCZ) to the Southern Hemisphere promoted dry and windy conditions in northern South America. An upper ~2-m thick unit was deposited when the climate became wetter after HS1, promoting the formation of soils that support open vegetation habitats. This study indicates that abrupt millennial-scale climate events can induce significant changes in the Amazonian landscape, which in turn play an essential role in the distribution and diversification of specialized biota. Highlights • An open vegetation habitat in northern Amazon formed after abrupt climate events. • Persistent southern shifts of the ITCZ during the LGM and HS1 favored dune-building. • Dunes underpin white sand vegetation and cerrado habitats which harbor endemic species. [ABSTRACT FROM AUTHOR]

Abstract The concept of "Carbonate Factory" was introduced to describe areas of carbonate production and accumulation. In this paper, the "Ooid Factories" is used to analyze extensive Griesbachian (Triassic) oolite deposits in South China that, along with microbialites and lime-mud deposits from different carbonate depositional environments. Late Permian tropical shallow-water skeletal factories (dominant by calcareous algae, sponge, and other associated organisms) collapsed in pace with the most severe mass extinction event, and were rapidly replaced by mud-mound factories (microbialite and lime-mud deposits) and subsequent ooid factories in shallow-water circumstances of Griesbachian. Meantime, temporal nutrient-rich and high-temperature conditions probably delayed re-establishment of tropical shallow-water skeletal factories. As an elementary unit of ooid factories, Lower Triassic oolites have diagnostic characteristics of ooid fabrics (alternatively dark- and light-colored laminae), size ranges (1–5 mm), and grain compositions (pure ooids, and only a few gastropod and bivalve fragments). Continuous aggradational and progradational oolite sequences caused extensive oolite accumulations that significantly contribute to the development of platform architecture with the collaboration of mud-mound factories (mainly line-mud deposits) in South China, through the evolution of low-angle or homoclinal ramps in the early Griesbachian to distally steepened ramps or flat-topped shelves in the late Griesbachian. Moreover, ooid factories also developed in Western Tethyan, Cimmerian, and Arabian carbonate platforms within low latitudes of the Tethyan Ocean during the Griesbachian. It is suggested that extreme hothouse climate with (seasonal) dry conditions in low latitudes significantly facilitated the extensive carbonate production of ooid factories at that time due to the strong linear relationship between surface seawater temperature and carbonate saturation state. Highlights • Our study focuses on "ooid factory" and introduces its characteristics during the earliest Triassic. • Tropical shallow water (skeletal) factory was replaced by ooid and mud-mound factories after the latest Permian mass extinction event. • Ooid factories were widely distributed in low latitudes during the Griesbachian. • Ooid and associated mud-mound factories have a great influence on early-stage platform architecture. • The high temperature of surface seawater and arid climate may relate to the operation of ooid factories. [ABSTRACT FROM AUTHOR]

Abstract The majority of assessments of future heat-related health risk are based on projections of heat hazards superimposed solely on current socioeconomic conditions, thus neglecting the potential contribution of drivers of heat stress risk other than climate change. Partly to address this drawback, the climate change research community has developed a new scenario framework, made up of distinct sets of climate and socioeconomic scenarios. The few assessments of future heat-related health risk that have employed this new framework have focused on changes in population exposure but have often not accounted for future populations' vulnerability. In this paper, we combine European Shared Socioeconomic Pathways with Representative Concentration Pathways to provide spatially explicit European projections of heat-related health risk that account for multiple changes in both socioeconomic and climatic conditions. In doing so, we also address the challenge of accounting for projections of determinants of vulnerability under varying levels of socioeconomic development. Results reveal that the proportion of the European population at very high risk of heat stress will show a steady increase – from 0.4% currently to 20.3%, 32.6%, or 48.4% in 2050 depending on the scenario combination – unless substantial political changes occur rapidly and steadily shift the current socioeconomic development pathway towards sustainability. Ambitious mitigation policies associated with rapid technological progress to enhance human capital could also moderate future heat-related health challenges. Such challenges are unevenly spread across Europe, with the Mediterranean region and Scandinavia being respectively the most and the least impacted regions. Future heat-related health challenges are substantially influenced by varying levels of socioeconomic development, primarily through changes in vulnerability – changes in population exposure being only of secondary importance. The former may even have a more significant impact on future heat stress risk than climate change, particularly in the British Isles and in the Iberian Peninsula. Thus, there is an undeniable necessity to consider the future state of vulnerability – and its uncertainties under varying socioeconomic scenarios – when assessing future heat-related health challenges and designing health adaptation strategies. [ABSTRACT FROM AUTHOR]

Abstract The summer circulation over the eastern Mediterranean is characterized by a persistent northerly regime whose interannual variability is modulated both by mid and tropical latitudes. In this paper, we use historical wind observations taken aboard ships to assemble the first purely instrumental index quantifying this wind system since 1880. This has allowed evaluating the multidecadal and interannual variability of the northerlies in the eastern Mediterranean over the longest time period so far. Our results indicate that the first half of the 20th century was characterized by more frequent and persistent northerly winds in the eastern Mediterranean than the second half. We have also found that the well-known teleconnection between the eastern Mediterranean summertime winds and the Indian Summer Monsoon, with enhanced northerlies concurrent with a stronger monsoon, has not been steady along the 20th century. It is shown that the Indian summer monsoon modulation of convection over the western Indian Ocean plays a crucial role in the strength of this connection. Highlights • A new index based on historical wind observations allows the characterisation of the EM northerly winds back to 1880. • The EM northerlies exibit significant variability at multidecadal timescales. • The relationship between the EM northerlies and the ISM shows different regimes in the last 135 years. [ABSTRACT FROM AUTHOR]

Abstract: Rapid, or abrupt, climate change is regarded as a change in the climate system to a new state following the crossing of a threshold. It generally occurs at a rate exceeding that of the change in the underlying cause. Episodes of rapid climate change abound in the recent geological past (defined here as the interval between the last glacial maximum, dated to approximately 20,000years ago, and the present). Rapid climate changes are known to have occurred over time periods equal to or even less than a human lifespan: moreover, their effects on the global system are sufficiently large to have had significant societal impacts. The potential for similar events to occur in the future provides an important impetus for investigating the nature and causes of rapid climate change. This paper provides a brief overview of rapid climate change and an introduction to this special issue, which presents results generated by the palaeoclimatic component of the UK Natural Environment Research Council''s rapid climate change programme, called RAPID. The papers in the special issue employ palaeoclimatic proxy data-sets obtained from marine, ice core and terrestrial archives to reconstruct rapid climate change during the last glacial cycle, its subsequent termination and the ensuing Holocene interglacial; some papers also report new attempts to match the palaeoclimate data to hypothesised causes through numerical modelling. The results confirm the importance of freshwater forcing in triggering changes in Atlantic meridional overturning circulation (MOC) and the close links between MOC and rapid climate change. While advancing our understanding of these linkages, the RAPID research has highlighted the need for further research in order to elucidate more specific details of the mechanisms involved. [Copyright &y& Elsevier]

Abstract: Climate change in the Mediterranean region cannot be understood without taking into account changes in the Mediterranean Sea, which is an important source of moisture and heat for the Mediterranean climate system. Many research papers have been published in the last two decades increasing our knowledge about long-term trends and inter-annual variability of temperature and salinity in the Western Mediterranean. Although recent changes have been better documented, there remain uncertainties because different results are obtained depending on the period of time analyzed or the geographic region selected. This paper analyses the regional, seasonal and decadal variability of sea surface temperature in the Western Mediterranean basins (Northern (Ligurian Sea and Gulf of Lions), Balearic, Algerian and Alboran) by means of thermal satellite images. Monthly data from the PO.DAAC (Physical Oceanography Distributed Active Archive Center) have been processed for the period 1985–2007. Results show an averaged warming linear trend of 0.03°C/yr. This rate is higher during the spring (0.06°C/yr) in all the basins and the highest values were registered in the Northern basin in June. The study suggests that an early warming of the Sea is occurring in all the basins during the spring, with an increment of 0.5–1°C in the mean SST of April, May and June over the two decades studied. The analysis of thermal anomalies confirms the warming trend with a dominance of negative anomalies during 1985–1996 and a dominance of positive anomalies during the last decade (1997–2007). Intense anomalies are more frequent in the Northern basin. [Copyright &y& Elsevier]

Abstract: This study was conceived to evaluate the global scientific output of climate change research over the past 18years and to assess the characteristics of the research patterns, tendencies, and methods in the papers. Data were based on the online version of Science Citation Index Expanded from 1992 to 2009. Articles referring to climate change were assessed by distribution of source countries, source institutes, paper titles, author keywords, KeyWords Plus, abstracts, and the most cited articles in these years. By synthetic analysis of the four kinds of keywords, it was concluded that the items “temperature”, “environment”, “precipitation”, “greenhouse gas”, “risk”, and “biodiversity” will be the foci of climate change research in the 21st century, while “model”, “monitoring”, and “remote sensing” will continue to be the leading research methods. A novel method, “phylogeography”, may have a strong application potential in the near future. [Copyright &y& Elsevier]

Abstract This paper illustrates a new compilation of sea-surface hydrographic data (SST mainly) derived from multiproxy reconstructions on high time-resolution (decadal to centennial) marine archives. This compilation is focussed on the boreal Atlantic and gathers Holocene sedimentological records (defining the HAMOC database) which were retrieved in the vicinity of the subpolar and subtropical oceanic gyres. It provides for the first time a 12 ka long and multi-sourced (i.e. from different ecological groups) document of the evolution of sea-surface parameters over the North Atlantic, highlighting common regional trends but also discrepancies which need to be considered and integrated to further understand the Atlantic circulation dynamics and related climatic modes. Selective records have been extracted from the database and their significance tested considering proxy-dependent responses. This sheds light on the importance of intrinsic meaning carried by each proxies, often misconsidered and eluded while they typify critical ecological changes (living depth, seasonality of blooms, ect). To disentangle those changes is not easy and implies integrating artefacts linked both to ecological adaptations and environmental shifts (themselves being nested), but needs urgently to be considered in future works as it is the only way to progress in our knowledges of the (living) ocean resilience to climate hazards. Highlights • Reconstructions of Holocene sea-surface conditions within the North Atlantic call for multiproxy sourced data. • The Holocene Oceanic regionalism may mirror modern climatic modes. • The Holocene climatic dynamics is intimately coupled to the oceanic one. [ABSTRACT FROM AUTHOR]

Abstract Recent global warming has not been ubiquitous: there are seasons, regions, and time periods with negligible or even negative air temperature trends (frequently referred to as warming holes). This paper presents a novel method enabling a proper localization of specific trend events, such as periods of warming holes, of a particularly strong warming, and of rapid transitions of trend amplitudes during the calendar year. The method consists in analyzing trends for periods of a given length (10 to 90 days) that are sliding over the year with a one day step. This allows a detailed description of the annual cycle of trends. The analysis is conducted for daily maximum and minimum temperature at 135 stations in Europe in 1961–2000. Despite an overall warming in Europe, several warming holes are uncovered during various parts of the year, not only in autumn when a warming hole has already been reported. The autumn warming hole concentrates in Eastern Europe, but it changes its strength and spatial extent: it spreads into Western Europe in September and retreats to Eastern Europe in November when it intensifies especially north of the Black Sea. Three shorter warming holes are detected: In February and March, cooling occurs in the Eastern Mediterranean and Iceland, while in early April, cooling is detected over Central, Southern, and Southeastern Europe. Another large-scale cooling occurs in Central, Northern, and Northwestern Europe in mid-June. The periods of strongest warming occur around the middle of January in Eastern Europe, in early March over almost entire Europe, and in mid-May and early August mainly over Central and Western Europe. Cluster analysis of stations with respect to the annual cycles of trends demonstrates a spatial coherence of the trends; the lack of spatial coherence points to local peculiarities or data problems of individual stations. The method of sliding seasons proves to be much more effective in the identification and localization of notable trend events than the ordinary approach of trend detection for fixed calendar seasons and/or months. Highlights • Annual course of temperature trends in Europe in 1961–2000 using "moving trends" • "Subseasons" of 10–90 days shifted by 1 day during the calendar year • Shorter subseasons = higher temporal and spatial variability of temperature trends • Greatest warming in January in NE Europe due to high interannual variability • "Warming holes" (i.e. cooling) in autumn in Central&E Europe, in June in N Europe [ABSTRACT FROM AUTHOR]