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From the early Holocene onward, the Indian Subcontinent has accommodated a range of diverse human cultures and associated ecological adaptations and lifestyles. Around 10 kyrs ago, the Subcontinent has witnessed the development of later Mesolithic hunter-gatherers and their subsequent regional transitions to pastoralist (Neolithic) and agricultural (Chalcolithic) lifeways. The Holocene climate records reveal discrepancies in the timing and duration of climatic events, which can be attributed to a vast geographic isolation, the influence of height, elevation, and local climatic conditions. These changing climatic patterns including the development of a geographically variable monsoon directly impacted these various cultures including the Harappans and their contemporaries as well as younger Historical and Medieval empires across India, at various levels. In some regions, environmental changes led to uneven cultural transitions, geographic migrations, and the development of regionally-distinct material cultures along with establishment of sedentary life-ways. This paper attempts to present a review broadly correlating general climatic patterns throughout the Holocene period of India with regional cultural dynamics. All geomorphic-climatic zones of the Subcontinent showed strong inter-proxy coherence between 9 and 5 kyrs in response to increased precipitation. After this warming period ends, we see a moderate dry period as a result of a weakening monsoon and an overall tendency toward aridity throughout all zones (after 4 kyrs). The temporal variation of human habitation and respective adaptive responses suggest broad linkages to the varying climatic and physiographic features at a regional scale. Learning how this shaped human eco-dynamics in the past can help us expand our understanding of human history and implement lessons for the present as well as the future. [ABSTRACT FROM AUTHOR]

This paper explores long-term trends in human population and vegetation change in the Levant from the early to the late Holocene in order to assess when and how human impact has shaped the region's landscapes over the millennia. To do so, we employed multiple proxies and compared archaeological, pollen and palaeoclimate data within a multi-scalar approach in order to assess how Holocene landscape dynamics change at different geographical scales. We based our analysis on 14 fossil pollen sequences and applied a hierarchical agglomerative clustering and community classification in order to define groups of vegetation types (e.g. grassland, wetland, woodland, etc.). Human impact on the landscape has been assessed by the analysis of pollen indicator groups. Archaeological settlement data and Summed Probability Distribution (SPD) of radiocarbon dates have been used to reconstruct long-term demographic trends. In this study, for the first time, the evolution of the human population is estimated statistically and compared with environmental proxies for assessing the interplay of biotic and abiotic factors in shaping the Holocene landscapes in the Levant. [ABSTRACT FROM AUTHOR]

The topic of this paper is the importance of climate for the population and settlement in medieval and early modern times. Were the demographic crises caused by crop failure and famine or by disease? I begin by reviewing European research (particularly English) relating to the issue. The views of Norwegian historians regarding the causes of the agrarian crisis in the late Middle Ages are then examined. Hasund (Hasund S, 1919, 1944, Den store mannedauden. Or Noregs bondesoge. Glytt og granskingar II, Oslo, pp. 82–161. First printed in Beretning om Norges Landbrukshøiskoles virksomhet 1918–1919) claimed it was the plagues, not the climate, that held the population at a low level to the end of the Middle Ages, a view that has been repeated in recent years by such researchers as Lunden (Lunden K, 2002, Norges landbrukshistorie II, 1350–1814. Frå svartedauden til 17. mai. Oslo) and Moseng (Moseng OG, 2006, Den flyktige pesten. Vilkårene for epidemier i Norge i seinmiddelalder og tidlig nytid. Oslo). This paper claims that the role of the climate has been underestimated, in particular that the climatic shock of several bad years in a row directly and indirectly brought appreciable excess mortality in a country situated so far north. ‘Bad’ years demonstrated through dendrochronology are in many cases reflected in documentary evidence concerning poor corn harvests and high mortality. [ABSTRACT FROM PUBLISHER]

Aerosols affect climate by scattering and absorbing radiation and by modifying the physical and radiative properties of clouds. Despite their importance in the climate system, the temporal and spatial variability of aerosols is not well understood. This paper briefly describes the nature of aerosols, their influence on the climate system and methods for quantifying atmospheric turbidity,which is the total column amount of aerosol. The main focus of the paper is a review of turbidity research that serves to document how and why aerosols vary over time and space. This analysis reveals that temporal and spatial variability in aerosol emissions is superimposed by temporal and/or spatial variability in meteorological and climatic factors. These factors include variability in wind speed, humidity, stability, insolation, frontal and cyclonic activity,the position of the Intertropical Convergence Zone and the polar front, rates of precipitation and convection, and the source regions of air masses. This interaction between aerosol emission characteristics and atmospheric processes is manifested in distinct trends in total column aerosol - described herein by geographic region - at a variety of spatial and temporal scales. [ABSTRACT FROM AUTHOR]

Based on compilation of a large number of archaeological and palaeosol 14C-ages, the Summed Probability Method is used to reconstruct population history and climatic patterns on the Chinese Loess Plateau during the period 8.5–3.5 cal. ka BP. During this period, the population experienced two major expansion periods and several climatic fluctuations. The first population expansion began at around 7.8 cal. ka BP, and the second at around 5.8 cal. ka BP. During the first period, although already in combination with cultivation of broomcorn millet the population growth was supported mainly by hunting and gathering. With the switch from broomcorn millet to foxtail millet, plant cultivation became the major factor promoting a second population increase. In this paper, we demonstrate that, initially, suitable climate and agriculture both can facilitate population growth and climate events had a significant influence on demographic fluctuations. However, when reaching the threshold of land capacity, population became increasingly more sensitive towards climate fluctuations. [ABSTRACT FROM AUTHOR]

This paper argues for an increased emphasis on the institutions of risk governance and management in understanding urban resilience. This moves analysis of vulnerability away from a focus on individuals to also consider risk management regimes as co-productive of vulnerability and resilience in the City. This is illustrated through the application of an Adaptive Capacity Index to unpack the role played by formal governance institutions in mediating resilience to extreme heat events in the empirical case of London. Analysis shows that the configuration of risk at the institutional level directs heat wave risk management through the health services, and operationalises it during the emergency phase of hazard onset. This misses an important opportunity for integrating individual and regime level risk management initiatives, which we proposed can be worked out through greater collaboration with social services and interaction with those caring for the vulnerable, has yet to be fully integrated into planning and practice in London and elsewhere. [ABSTRACT FROM PUBLISHER]

Peatlands represent the largest and most concentrated carbon pool in the terrestrial biosphere, and their dynamics during the Holocene have had significant impacts on the global carbon cycle. In this Introduction paper, we provide an overview of the contributions presented in this Special Issue on Holocene peatland carbon dynamics. We also provide a brief history and current status of peat-core-based research on peatland carbon dynamics. Finally, we identify and discuss some challenges and opportunities that would guide peatland carbon research in the near future. These challenges and opportunities include the need to fill data gaps and increase geographic representations of peat carbon accumulation records, a better understanding of peatland lateral expansion process and improved estimate of peatland area change over time, developing regional carbon accumulation histories and carbon pool estimates, and projecting and quantifying overall peatland net carbon balance in a changing world. [ABSTRACT FROM PUBLISHER]

It has been argued that Central European lake levels were driven by solar activity. This interpretation rests on the comparison of a score record of radiocarbon dates with the 14C residual curve. This score record is a variant of a cumulative probability density function (CPF). In this paper it is argued that this method is not valid because the shape of the CPF is determined by the calibration curve. This hypothesis is tested by a set of null models. An alternative interpretation is given according to which only few episodes of Holocene lake-level changes were climatically driven, while most of the time non-climatic factors were dominating. On a more general level some methodological issues of CPFs are discussed and exemplified by the comparison of dendrochronological results from archaeological settlements and a CPF created using radiocarbon dates from the same settlements. [ABSTRACT FROM PUBLISHER]

Rift Valley fever is a disease of animals and humans found throughout much of Africa, and recently in the Arabian Peninsula. It is spread via mosquito vectors and direct contact with infected tissue and fluids. Climate variability and change alter ecological processes involved in the outbreak and spread of diseases such as Rift Valley fever. This progress report reviews the key research literature on climate-driven environmental change and Rift Valley fever. The roles of regional and seasonal climates for the disease are emphasized, as well as remote sensing and other approaches to monitoring and analysis. The paper concludes with five suggested future directions for research. [ABSTRACT FROM AUTHOR]

Earth system science (ESS) is an approach to: 'obtain a scientific understanding of the entire Earth system on a global scale by describing how its component parts and their interactions have evolved, how they function, and how they may be expected to continue to evolve on all timescales' (Bretherton, 1998). The aim of this review is to introduce some key examples showing the role of Earth surface processes, the traditional subject of geomorphology, within the interacting Earth system. The paper considers three examples of environmental systems in which geomorphology plays a key role: (1) links between topography, tectonics, and atmospheric circulation; (2) links between geomorphic processes and biogeochemical cycles; and (3) links between biological processes and the Earth's surface. Key research needs are discussed, including the requirement for better opportunities for interdisciplinary collaboration, clearer mathematical frameworks for Earth system models, and more sophisticated interaction between natural and social scientists. [ABSTRACT FROM AUTHOR]

This paper interprets macroscopic charcoal (>250 μm), humification and loss-on-ignition over the last ∼14 200 cal. BP from Goochs Swamp, located to the west of Sydney in the Greater Blue Mountains World Heritage Area. This study aimed to investigate relationships between humans, climate and fire through time, primarily by comparison of these palaeoenvironmental indices with archaeological evidence from the region. Climatic forcing can explain all periods of change in the history of fire at Goochs Swamp: fire activity was variable during the Lateglacial-Holocene transition, low during the relatively stable climate of the early Holocene, and high but variable after the onset of modern El Niño from the mid Holocene. Although the dominant control on fire in this environment during the Holocene appears to be climate, fluctuations in the late Holocene may reflect anthropogenic fire or human responses to climate change. The archaeological record of the Blue Mountains and other parts of the Sydney Basin illustrates that Aboriginal people altered subsistence, resource and land-use patterns in the late Holocene. We propose that these cultural measures were adopted to overcome new risks as the frequency of ENSO events increased, and the natural fire regime and resource reliability changed. These strategies perhaps included a more systematic use of fire. The most parsimonious interpretation of the evidence for changes in fire activity at Goochs Swamp in the light of nearby archaeological evidence is that Aboriginal people used fire within a changing climatic framework. [ABSTRACT FROM AUTHOR]

The paper explores the use of Resilience Theory to provide an improved theoretical framework for the analysis of socio-ecological interactions over decadal—millennial timescales. It identifies landscape system behaviour through analysis of proxy records for land use, erosion and monsoon intensity over the past 3000 years in the Erhai lake-catchment system, Yunnan, SW China. Analysis of the records shows the possibility of alternative steady states in the landscape, as expressed by the relationship between land use and erosion. In particular, a period of agricultural expansion ~1400 cal. yr BP triggered rapid gully erosion that led to the formation of an eroded landscape state that has existed since ~800 cal. yr BP to the present day. Comparison of detrended time-series data suggests that over 3000 years erosion and land use should be considered 'slow' processes relative to the 'faster' monsoon intensity and flooding. In the past, the effects of high monsoon variance on flooding have been suppressed by paddy farming and the maintenance of terraced field systems. Mapping the Adaptive Cycle on to the millennial record of land use and erosion suggests that the modern landscape may be approaching a 'conservation' phase characterized by minimum resilience. Such 'historical profiling' of modern landscapes offers a new dimension for hypothesis testing, for the development and testing of simulation models and for the creation of appropriate management strategies. [ABSTRACT FROM AUTHOR]

Large, infrequent fires (LIFs) can have substantial impacts on both ecosystems and the economy. To better understand LIFs and to better predict the effects of human management and climate change on their occurrence, we must first determine the factors that produce them. Here, we review local and regional literature investigating the drivers of LIFs. The emerging conceptual model proposes that ecosystems can be typified based on climatic conditions that determine both fuel moisture and fuel amount. The concept distinguishes three ecosystem types: (1) biomass-rich, rarely dry ecosystems where fuel moisture rather than fuel amount limits LIFs; (2) biomass-poor, at least seasonally dry ecosystems where fuel amount rather than fuel moisture limits LIFs; and (3) biomass-poor, rarely dry ecosystems where both fuel amount and fuel moisture limit the occurrence of LIFs. Our main goal in this paper is to discuss the drivers of LIFs and the three mentioned ecosystem types in a global context. Further, we will discuss the drivers that are not included within the ‘fuels’ versus ‘climate’ discussion. Finally, we will address the question: what kinds of additional information are needed if models predicting LIFs are to be coupled with global climate models? As with all generalizations, there are local deviations and modifications due to processes such as disturbance interaction or human impact. These processes tend to obscure the general patterns of the occurrence of LIFs and are likely to cause much of the observed controversy and confusion in the literature. [ABSTRACT FROM AUTHOR]

River basins in Great Britain and Ireland have been characterized by periods of hillslope and valley floor instability during the Holocene, reflecting sensitivity to both climate change and anthropogenic disturbance. In contrast to climatic controls, which have been relatively well documented, human impacts on and interactions with river basins remain unclear. There is now, however, a growing impetus to elucidate more fully the impact of anthropogenic activity on sediment supply and runoff, given that land-use change is thought to have exacerbated recent flooding in the UK (eg, the 'Millennium' floods of 2000). The aim of this paper is to critically review the significance of Holocene land use on hillslope and valley floor stability in Great Britain and Ireland. The most widely reported impacts of land-use change on geomorphic activity include hillslope erosion and gully development, valley floor alluviation, river channel incision and elevated water tables. In the majority of cases, however, causal relationships are difficult to establish, due primarily to inadequate dating control. Even where geomorphic instability can be linked to land-use change, it is apparent that eroded material is often stored as colluvium, which together with evidence of diachronus hillslope and valley floor instability, raises important questions and identifies uncertainties regarding the dynamics and extent of sediment transfer within river basins. Such uncertainty has important implications for understanding how river basins will behave in response to future environmental change. [ABSTRACT FROM AUTHOR]

This paper examines variability in surface climate and the relationship with two circulation indices using recently produced 200-250 year long European daily and monthly climatic series. Assessments are made of the influence of circulation indices (zonal over western Europe and average pressure over central Europe) on regional temperature, precipitation and drought series for northern and central Europe. Changes in the circulation are shown to be very important during the winter in northern Europe, but only over western and central Europe in summer. Circulation indices in winter, however, only explain up to 25% of surface-climate variability and, except for the British Isles, do not explain any decadal and longer timescale variability in summer. Extreme temperatures and growing-season and frost-season durations and degree-day series are calculated for four sites (Central England, Stockholm, Uppsala and St. Petersburg). Degree-day counts are shown to be very strongly correlated (r > 0.9) to average extended summer ('growing' season, May to September) and extended winter ('frost' season, October to April) temperatures. Durations of the growing and frost seasons are only weakly correlated (r ∼ 0.2-0.4) with the appropriate extended seasonal temperatures or degree-day counts. Warmer growing/frost seasons, therefore, need not necessarily be longer/shorter. Counts of extremely warm days in each year are more highly correlated with the growing-season mean temperature than with coldseason temperature. Similarly, counts of extremely cold days in each year are more highly correlated with cold-season temperature than with growing-season temperature. Both the growing-season temperature and the corresponding degree-day counts clearly show warmer temperatures over all series in Fennoscandia before 1860. Over central Europe, and for the Central England temperature series, growing seasons now are of similar warmth to those before 1860. Annually averaged temperatures across the three regions indicate long-term warming which is, however, almost entirely the result of warming during the October to April period. [ABSTRACT FROM AUTHOR]

This paper presents a multiproxy high-resolution study of the past 2600 years for Seebergsee, a small Swiss lake with varved sediments at the present tree-line ecotone. The laminae were identified as varves by a numerical analysis of diatom counts in the thin-sections. The hypothesis of two diatom blooms per year was corroborated by the [sup 210]Pb and [sup 137]Cs chronology. A period of intensive pasturing during the 'Little Ice Age' between AD 1346 and AD 1595 is suggested by coprophilous fungal spores, as well as by pollen indicators of grazing, by the diatom-inferred total phosphorus, by geochemistry and by documentary data. The subsequent re-oligotrophication of the lake took about 88 years, as determined by the timelag between the decline of coprophile fungal spores and the restoration of pre-eutrophic nutrient conditions. According to previous studies of latewood densities from the same region, cold summers around AD 1600 limited the pasturing at this altitude. This demonstrated the socio-economic impact of a single climatic event. However, the variance partitioning between the effects of land use and climate, which was applied for the whole core, revealed that climate independent of land use and time explained only 1.32% of the diatom data, while land use independent of climate and time explained 15.7%. Clearly land use influenced the lake, but land use was not always driven by climate. Other factors beside climate, such as politics or the introduction of fertilizers in the seventeenth and eighteenth centuries also influenced the development of Alpine pasturing. [ABSTRACT FROM AUTHOR]

In his comment on Bleicher (2013) Magny presents a revised version of his score method and reaffirms that it can prove a possible influence of solar activity on Central European lake levels. He also stresses the diagnostic value of archaeological lake site settlements. This paper points at methodological problems that are not yet resolved in the revised version. Since there is great consensus that not only is the the Sun a primary forcing factor in the climate’s system, but also that its effect cannot be expected to be linear for all of the Holocene, the use of the score record is questioned. The proposed relation between archaeological lake site settlements and solar activity is shown to be doubtful. [ABSTRACT FROM AUTHOR]