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The Indo-Pacific Warm Pool (IPWP) is the primary supplier of heat and moisture to the global atmosphere, and exerts a significant impact on tropical and worldwide climate variability. This special issue expands our understanding of the paleoceanographic and paleoclimatic evolution of the IPWP since Neogene times with implications for understanding future change. It contains fifteen research articles addressing two primary themes: (1) Ocean-atmosphere coupled processes via the ocean water-column, sea surface, atmospheric evaporation/precipitation; and (2) Sediment source-to-sink and biogeochemical carbon-cycles, and their interactions with oceanographic, hydrological, tectonic and other factors. These contributions improve our understanding of thermocline temperature, salinity, oxygenation, hydrography, carbon cycle, biological productivity, and sedimentary response in the IPWP across Neogene and Quaternary time scales, as well as aiding in the forecast of future climate responses in the context of current global warming. The special issue will capture the attention of geologists, climatologists, and anybody else interested in global climate change. • This is the editorial preface for the VSI on Indo-Pacific Warm Pool. • 15 papers are included and shortly introduced. • Two themes are included. • The 15 papers provide new views on paleoceanographic and paleoclimatic changes in the Indo-Pacific Warm Pool. [ABSTRACT FROM AUTHOR]

Product service systems (PSS) are an example of a novel business model billed as having the potential to significantly reduce the environmental burdens of production and consumption processes. However, despite widespread interest in PSS, consensus regarding their actual environmental impacts, particularly with regard to salient issues such as global warming, is lacking. Hence this paper explores existing research to investigate the state of the art regarding the climatic impacts of PSS, alongside the set of factors that influence climatic impacts. The paper comprises a systematic review of peer-reviewed academic literature, quantifying the extent to which different types of PSS have the capacity to reduce greenhouse gas emissions across multiple product categories. Our study shows that significant reductions in climatic emissions are possible, but PSS are in many cases associated with more modest reductions and, in some cases, increased emissions. Further, we observe no clear differences in climatic impacts according to the type of PSS model that is deployed. Rather, differences in climatic impact are influenced by factors such as production and design alongside use-phase impacts and contextual factors such as transportation and the energy mix. The study argues that further research is needed to establish a more robust baseline upon which to draw conclusions regarding the sources of climatic impacts, and outlines fruitful ways for companies to tackle the complexities of climatic emissions that are beyond their control. • In some cases, product service systems can reduce climatic impacts by up to 80%. • In other cases, climatic impacts increase compared to traditional product sales. • Climatic impacts are influenced by use intensity, transportation and production. • Other contextual factors such as the energy mix play a role. • More quantitative assessments are needed with less reliance on estimations. [ABSTRACT FROM AUTHOR]

The building sector is critical in climate change mitigation by reducing its energy consumption. At the same time, warming climate requires adaptation measures from buildings, making it necessary to study the future thermal energy demand of buildings. This paper studies the impact of climate change on the thermal energy demand of buildings in a heating dominated climate of Finland, under "representative concentration pathway" (RCP) climate scenarios in near- (2030), medium- (2050) and long-term (2080) horizon. Additionally, the impact of the thermal performance level of the buildings is investigated. The thermal energy demand calculation is based on overarching standards from the European "energy performance of buildings" directive. The weather scenarios present both typical and extreme weather years, applied through morphing and future weather data from the Finnish Meteorological Institute. The results show that annual thermal energy demand in Finland in 2080 can decrease up to 74.6 kWh/m 2. In addition, the decrease in heating demand will be higher than the increase in cooling demand. Cooling can become the dominant peak in long-term evaluations, especially in South Finland (Vantaa) with passive buildings under RCP8.5 climate scenario. Renovation is the most efficient action to decrease energy intensity, the earliest it is done the better. [Display omitted] • Thermal energy demand of detached houses in Finland is studied under RCP climate scenarios. • Thermal energy demand is expected to decrease in Finland in long-term. • RCP scenario affects when the highest average annual thermal energy change occurs. • Cooling can become the dominant thermal peak demand source for passive buildings. • Renovating building to newer standards remains beneficial, though less with time. [ABSTRACT FROM AUTHOR]

The Arctic Ocean is rapidly warming. In this paper, we document changes in the source, distribution, and accumulation rate of organic matter (OM) for three sediment cores in the Bering and Chukchi seas to investigate changes to the oceanic carbon cycle over the past ∼75 years. Analyses were undertaken using bulk properties, such as total organic carbon (OC), total nitrogen (TN), stable carbon isotope (δ13C), OC to TN molar ratio (C/N), and biomarkers (lignin phenols). The OC, TN, and lignin (Σ8, in mg (g sediment)−1) contents were found to be significantly related to the fraction of sand (Sand%) as a result of sediment sorting and/or different sediment sources. Using an end-member mixing model, we estimated marine OM accounted for ∼67% of all organic matter in all cores, being the dominant source. Moreover, terrestrial OM mainly originated from angiosperm non-woody tissue, while moss contribution was negligible. In the Bering Sea shelf, OC% has not changed over time, but there have been some extreme peaks around the 1960s–1970s and in 2005, which correspond to increased terrestrial input from North American rivers. In the southern core from the Chukchi Sea, the OC% showed an apparent decrease after 2000, accompanied by an increase in sand content, likely due to enhanced delivery of volcanic rocks by the Pacific Inflow from the Bering Sea. In contrast, in the northern core from the Chukchi Sea, the OC% showed a significant increasing trend, with some peaks occurring at the same time as in the Bering Sea core. The mean increase rate was compared to the increase in Siberian riverine discharge, which both could be caused by long-term climate changes. The results highlight the regional differences in the response of OC preservation to climate change and other controlling factors. Further studies with higher spatial resolution are required to better understand the preservation of OC in response to climate change. [Display omitted] • The main vegetation source was vascular plant, contribution from moss was limited. • Marine source accounted for ∼67% of the sedimentary OC in the (sub)Arctic cores. • OC preservation changed differently in the (sub)Arctic Ocean in past decades. [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]

The purpose of this study is to analyze the spatiotemporal variations in drought in Serbia over recent decades using the standardized precipitation evapotranspiration index (SPEI). The analysis is performed for time series of 1-, 3-, 6-, and 12-month SPEI indices (SPEI-01, SPEI-03, SPEI-06 and SPEI-12, respectively) calculated using the E -OBS gridded dataset with a horizontal resolution of 0.1° for the period of 1950–2022. In general, it was found that negative SPEI trends prevailed in Serbia for all months and all analyzed SPEI timescales, indicating a more frequent appearance of droughts in recent decades. Moreover, for a large majority of month-timescale combinations, the area with a negative trend was larger than the area with a positive trend. For several reasons, we focused on the SPEI for August. First, the SPEI for this month shows one of the most pronounced negative trends, which is rather consistent over different timescales and consistent in terms of the area over which the trend was found to be significant. Statistically significant negative trends of SPEI-03, −06 and − 12 for August were found over 11, 17 and 38% of the country area, respectively. To better understand the trends and changes in the SPEI for August, focusing on extreme and severe drought events, an innovative trend analysis (ITA) was applied. It was found that the occurrence of both extreme and severe SPEI drought categories has doubled over the last thirty years in comparison with the previous thirty-year period. Additionally, more frequent transitions from neutral and wet categories to dry categories were observed through an application of the Markov chain. Second, the special focus on SPEI-03, −06 and − 12 for August was motivated by the fact that we found a significant correlation between these index values and the annual maize production in Serbia, indicating that the SPEI for August can be useful for the assessment of drought impact on agriculture. To better understand interannual variability and long-term trends, this paper also explores the relations between the SPEI over Serbia and large-scale circulation patterns, together with general global and continental warming trends. Our findings indicate that drought changes over recent decades may be driven by the interplay of long-term warming and large-scale circulation patterns. In the context of climate change, especially climate projections, Serbia is situated in a region for which climate projections of mean precipitation change demonstrate weak signals and often with conflicting signs of change within multimodel ensembles. From this point of view, our results can be seen as a contribution to a better understanding of changes in extremes, in our case droughts, that can be hidden by inconclusive changes in the mean values. Finally, due to the similar situation in terms of precipitation and drought trends and changes, our results may be relevant for a wider region, and not only for Serbia. • For Serbia negative trends in SPEI index, for different months and timescales, are dominant. • Occurrence of extreme drought categories has doubled over the last decades. • Transitions from neutral and wet categories to dry categories are more frequent. • These changes are driven by long-term warming and large-scale circulation patterns. [ABSTRACT FROM AUTHOR]

France is one of the countries that have made commendable progress towards accomplishing sustainable development goals but still struggles with combating environmental challenges. Decarbonizing the energy sector by deploying clean energy and reducing fossil fuels in the energy mix are essential steps. The study uses annual time series data from 1980 to 2021 and employs the ridge regression estimation technique to estimate a twice-differentiable transcendental production function, which approximates the second-order Taylor series to explore the potential for such decarbonization for France. The study finds that substitution possibilities exist between clean energy and fossil fuels, with substantial substitution possibilities coming from nuclear energy. Nuclear energy and renewables are found to be complements that can be deployed concurrently, but since nuclear energy already constitutes a significant proportion of clean energy for France, the study recommends increasing the proportion of renewable energy in the overall energy mix as the most plausible path to decarbonization. Other complementary sustainable energy policies are recommended in the body of the paper. • The substitution elasticities between clean energy and fossil fuels were estimated. • A second-order Taylor series trans-log production function was specified. • Substitutability is found between clean energy and fossil fuels. • Nuclear energy currently dominates France's clean energy mix. • Increasing renewables in the clean energy mix is recommended. [ABSTRACT FROM AUTHOR]

• We analyzed trends and breakpoints for three streamflow signatures of drying patterns in 540 non-perennial streams over CONUS • Nonlinear changes in streamflow are more common than linear changes for all three stream intermittency signatures. • The past behavior of non-perennial streams might be a poor predictor of future drying patterns Stream drying patterns – including duration, timing, and dry-down rates – affect aquatic ecosystems and nutrient exports in non-perennial streams. Because hydrologic processes are often nonlinear, changes in drying may also be nonlinear, but analyses of historical changes in stream drying to date have not characterized the frequency or functional forms of nonlinear change. Understanding the extent of nonlinear change in non-perennial streams is essential for advancing our fundamental knowledge of hydrological processes, aquatic ecosystems, and watershed functioning under a warming climate. This paper uses a polynomial-based trend detection technique (PolyTrend) to analyze the linear and nonlinear trend behaviors of three intermittency signatures (annual no-flow days specifying longer or shorter drying duration, day of first no-flow occurrence specifying timing of stream drying, and days from peak to no-flow specifying dry-down rates) at 540 non-perennial gage stations over 38 years (1980–2017) across the continental United States (CONUS). Additionally, we carried out a breakpoint analysis to characterize the discontinuities in the time series of each intermittency signature. Analysis of annual no-flow days shows that about 37 % of the total streamflow stations are drying for longer each year, whereas about 22 % are wetter for longer than in the past. The day of first no-flow occurrence analysis shows that 10 % of the streams are drying earlier, and 19 % are drying later. On the other hand, analysis of days from peak to no-flow shows that 14 % of streams are drying faster, and 17 % are drying more slowly. For all these metrics, among the significant trends, at least half of the relationships were nonlinear. For annual no-flow days , the breakpoint analysis shows more discontinuities in the second half of the analysis period (1999 to 2017) than in the first half, with more discontinuities in the Southern Great Plains than in other regions. The other two signatures demonstrate less frequent discontinuities in the second half of the analysis period, suggesting decreased nonlinear dynamics in recent years. Nonlinear no-flow duration trends are common in Mediterranean California, and the dry-down rate has increased in recent decades. Our findings indicate that nonlinear change in stream drying is widespread and must be accounted for in watershed planning and management. [ABSTRACT FROM AUTHOR]

Climate change has become a serious environmental matter of global concern. This paper attempts to verify if there is climatic change in Sub-Saharan Africa with the help of monthly station data from January 1901 to December 2020 on the mean temperatures of 48 countries of Sub-Saharan Africa. To do this, we employ fractional integration to account for the data's probable long memory feature. However, because other statistical features such as linear trends and seasonality might also be present in the data, we propose a broad framework that treats these three characteristics (long-range dependence, time trends, and seasonality) in a unified treatment. We first note that long memory is an observed feature in the data and using the original data, the time trends are found to be significant in Southern and Eastern countries, with higher coefficients being observed when the post-War II data are employed. When looking at the anomalies with respect to selected periods, long memory is found in all cases, and a higher number of trends are detected. Thus, 41 countries show significant time trends, with the values being higher again in the post WW2 sample, suggesting that industrialization might have contributed to global warming. The results also indicate some degree of heterogeneity across the African countries. • Examined mean temperatures in 48 countries through a monthly sample spanning January 1901 to December 2020. • Long memory is an observed feature in the data. • Time trends are found to be significantly positive in Southern and Eastern countries. • Higher coefficients are observed when the post-War II data are employed. • The results also indicate some degree of heterogeneity across the African countries. [ABSTRACT FROM AUTHOR]

• Transition zones are the hotspots of bioclimatic changes under global warming. • Global warming extends growing season lengths but increases heat and water stresses. • Sustainable grasslands in China shrink and shift northwestward with global warming. Bioclimatic response to global warming is a key linkage between anthropogenic climate change and ecosystem sustainability, particularly for the impact-prone climate transition zones. This paper examines changes in heat-water conditions from 2006 to 2100 across China, using the fifth generation climate reanalysis from the European Centre for Medium-Range Weather Forecasts (ERA5) and bias-adjusted climate projections by the Coupled Model Intercomparison Project Phase 5 (CMIP5). We then assess the effects of these changes on habitat suitability for responsive ecosystems using a species distribution model. The results reveal significant changes in bioclimatic environments across dry–wet climate transition zones under the present-day climate and the RCP8.5 scenario. By the end of the 21st century, local growing season length (GSL) could extend by 60 days and 30 % of the GSL could be under heat stress. Water conditions worsen overall in both the air and the soil, despite some improvements in the middle parts of transition zones. With altered heat-water conditions, sustainable grasslands shift northwestward, with a reduction of approximately 131 million km2 (46.6 % relative to 2006–2010) in total area. These changes primarily arise from alterations in winter and spring heat-water conditions. Our findings highlight the climate transition zones as hotspots of ecosystem vulnerability demanding particular attention in impact assessment and adaptation studies. [ABSTRACT FROM AUTHOR]

• The mechanism of rolling resistance of asphalt pavements is presented. • The measuring and modelling approaches of rolling resistance are summarised. • The prediction methods of fuel consumption and environmental impact are reviewed. In the context of climate change and global warming, the attention on the environmental cost of pavements is increasing. To scientifically quantify the environmental cost of pavements, accurate prediction of rolling resistance and fuel consumption is important. In this paper, a comprehensive review on rolling resistance of asphalt pavements and its environmental impact was presented. At first, the commonly used definitions of rolling resistance and texture characterisation methods of pavement surface were introduced. Then, the influence of different factors on rolling resistance was discussed. Next, the measuring and modelling approaches of rolling resistance were reviewed. At last, methods which can be used to predict fuel consumption and environmental impact were presented. It was found that an ideal approach for texture characterisation of pavement surface is to make use of the entire wavelength spectrum of road profiles and consider the enveloping curve of tire treads. Furthermore, the fact that rolling resistance can be influenced by different factors introduces difficulties in accurate measurement and modelling of rolling resistance. Moreover, testing methods and conditions have a significant effect on the empirical modelling of rolling resistance, while it is difficult and time-consuming to consider all the energy loss in the computational modelling of rolling resistance. In addition, the prediction of fuel consumption and environmental impact highly depends on the formulating methods and measuring conditions. The work presented in this paper will help to gain more insight into rolling resistance and its environmental impact, which ultimately promotes the construction of environmentally friendly pavements. [ABSTRACT FROM AUTHOR]

In this paper, an innovative framework is introduced for assessing the impact of climate change on coastal structures, with a primary emphasis on modeling future climate conditions. The framework encompasses several key components: the development of a new climate emulator to facilitate multivariate extreme value analysis; a hybrid statistical–numerical wave propagation strategy; and the integration of a novel compound modeling approach specific to coastal structure sites. These advancements are designed to effectively manage multiple climate scenarios and models within the context of high uncertainty. The methodology is applied and validated for a coastal structure located on the Mediterranean coast in Spain. Focusing on compound wave and sea-level events, the projections indicate an increase in the frequency and severity of extreme conditions, exacerbating coastal impacts such as wave overtopping. For instance, the present-day 500-year coastal flooding level would be associated with a return period of 50 years by mid-century under a stabilization scenario and would be further reduced to 25 years under a high-emission global warming scenario, resulting in important consequences for structure performance if no adaptation is implemented. • Develops a framework for assessing the impact of climate change on coastal structures. • It develops a new climate emulator to facilitate multivariate extreme value analysis. • It encompasses a hybrid statistical–numerical wave propagation strategy. • It integrates a novel compound modeling approach specific to coastal structures sites. • It has been applied and validated for a coastal structure in Spain. [ABSTRACT FROM AUTHOR]

Radon can pose a serious risk on human health. At present, radon has been considered as the second leading cause of lung cancer after smoking. The potential risk of radon exposure in cold regions of Northern Hemisphere is increasing due to climate-induced permafrost degradation. In this paper, we took permafrost regions in the Northern Hemisphere as our study area. We performed an extensive literature review on the Web of Science (WoS), China National Knowledge Infrastructure (CNKI), and Google Scholar (GS). We divided these selected literatures into three groups: Group uranium, Group radon and Group permafrost and tried to reveal the impacts of distribution of uranium deposits/u-rich rocks and permafrost/permafrost degradation on radon concentration/migration in permafrost regions. Based our research, it is evident that uranium deposits or U-rich rocks provides an abundant source of U (Ra) for soils and groundwaters in permafrost regions, resulting in abnormally high concentrations of radioactive elements in soils and groundwaters. As a natural barrier, permafrost soils could screen the radon gas from migrating into underground dwellings and work-space in cold regions. However, permafrost degradation has been extensively observed and this trend is projected to continue under a warming climate. Permafrost degradation and ground ice melting, water exchange, gas emissions and thaw settlement have enhanced the ability of radon migration into dwellings and work space, which substantially endangers human health if long exposed. Our synthesis results also underline that the related research of radon migration and relation in permafrost regions are grossly inadequate and urgently needed. Research priorities include the mechanisms of radon migration in freezing, frozen, thawing and thawed soils/rocks, responses of release of radon sequestered in permafrost soils and radon migration in groundwater systems, among many others, to permafrost degradation. [ABSTRACT FROM AUTHOR]

• The extent of flooding in China is greater than in any other country. • Nearly 66% of China's landmass is submerged by flooding. • Financial toll of flooding accounts for approximately 1.42% of the annual GDP. • Various forms of climatic change contribute to flooding. The extent of flooding in China is more significant than in any other country. Our research reveals that approximately 66 % of China's landmass is submerged by flooding, affecting about 50 % of the population. Furthermore, the financial toll of flooding now accounts for approximately 1.42 % of the annual gross domestic product (GDP), which is almost 40 times higher than the corresponding figure for the United States. We have observed that Zhengzhou city in Henan province, which faced a devastating flood in 2021, received a significant amount of rainfall, specifically a total of 552.5 mm within a 24-hour period. The floods in Henan province in 2021 caused considerable damage, including impacting nearly 15 million people, resulting in almost 400 deaths, damaging over 10,000 square kilometers of agricultural land, causing almost $19 billion in economic losses, and leading to the collapse of over 35,000 households and damage to various properties. In a similar manner, the significant flooding that occurred in southern China in 2020 impacted approximately 7.1 million individuals across eight provinces and resulted in 54 fatalities, the collapse of 6,700 houses, and incurred a direct economic loss of US$3.33 billion. We found that rainstorms have significantly increased to 10 % in the last 60 years in China. In this paper, we delved into exploring the existing published articles, reports, and government and authoritative legal texts to analyze the causes and impacts of flooding in China's flood-prone regions and potential mitigation strategies to reduce the repercussions of distressing flood events. We believe this study will help policymakers by providing new insights while formulating policy to reduce the loss caused by high-level flooding. [ABSTRACT FROM AUTHOR]

This paper delves into the potential impact of a changing climate on the energy performance of European buildings. Research aims to provide a comprehensive evaluation of current energy requirements focusing on the envelope, considering existing regulations in national policies. Energy simulations are conducted at 94 locations across the European Union to cover the climatic variability and Koppen climate classification. The research analyzes future climate scenarios for the years 2030, 2050, and 2070, using three different Representative Concentration Pathways (RCP 2.6, 4.5, 8.5). According to a comprehensive analysis of heating, cooling, and overall energy performance, climate plays a significant role in buildings' energy balance. In moderately cool climate countries, the demand for air conditioning is projected to decrease in the years ahead. Conversely, in countries with a warm climate, there is a projected increase in the overall energy demand. Consequently, a revision of current energy regulations should be a priority. Providing insights into the relation between building design, energy efficiency, and climate change, the research identifies policy adjustments to ensure buildings can effectively respond to changing climatic conditions. A holistic and dynamic approach can support building design accounting for long-term impacts of climate change to create resilient and energy-efficient structures. • National building energy regulations of European Member States do not tackle climate change. • Over next decades, a decrease in heating demand is forecasted across all climate zones. • There is potential for a future considerable increase of cooling demand in Europe. • A reduction in total building energy demand in colder climates and an increase in warmer climates can be expected. • Revise national energy regulations, especially in warmer zones, to curb the expected rise in Europe's total energy demand. [ABSTRACT FROM AUTHOR]

This study explores the impact of political uncertainty on sustainable urban development by examining carbon emission trading systems (ETS) in four major markets in China (Beijing, Shanghai, Guangdong, and Hubei) from 2014 to 2022. As an alternative to carbon taxes, carbon ETS markets have become increasingly popular due to their success in reducing greenhouse gas emissions. However, their effectiveness is often hindered by political instability and uncertainty. Utilising logistic regression and AR(1)-GARCH estimations, we identify a negative relationship between political uncertainty and carbon trading volume. Our study also reveals significant variations in the responses of these markets to political uncertainty. The paper contributes to the understanding of how ETS markets operate in a complex and constantly changing political environment. We suggest that policymakers need to consider the impact of political uncertainty on carbon trading when designing and implementing urban policies that promote sustainable development. Additionally, our research contributes to the development of urban policies that can be effectively implemented in both developed and developing regions. • Local government official turnovers are used as the measurement of political uncertainty. • Daily transaction data from four carbon ETS markets (Beijing, Shanghai, Hubei and Guangdong) in China • Considered the probability and proportion of zero transaction day • Logistic regression and AR(1)-GARCH estimations • A negative relationship between political uncertainty and carbon transaction volume [ABSTRACT FROM AUTHOR]

The biomass of aquatic organisms largely determines the mass and energy flow within an ecosystem, but the long-term impact of environmental change on biomass is not well constrained for a number of clades. Here, we test the hypothesis that bivalve biomass is negatively impacted by warming climate over time. This study is based on a fossil marine bivalve fauna recovered from hemipelagic sediments deposited in the eastern Mediterranean during climate cycles (marine isotope stages (MIS) 22–18; 900–712 kyr B.P.) of the Early–Middle Pleistocene Transition. We reconstruct individual shell biomasses from fossils and discuss the various biotic and abiotic factors that controlled long-term shell biomass patterns across this important interval in the Earth climate system. The results are contrary to the original hypothesis, suggesting that the response to temperature is not universal. Nevertheless, a decrease in median biomass is observed during the MIS 19 warm period and can be possibly attributed to the combined effect of multiple drivers that cooperated at that critical time in the past, including higher temperature and primary productivity, reduced ventilation of the sea floor, biodiversity changes due to geographic range shifts, and considering species- and age-specific thermal tolerances. Generally, bivalve biomass at the community level is determined by relative abundance and shell biomass-frequency distribution. In our study, the relative abundance and median biomass of small species do not increase or decrease, respectively, in warmer periods. However, larger species are negatively affected by warming both in terms of relative abundance and biomass. • We reconstruct deep-water bivalve biomass for Pleistocene eastern Mediterranean from fossil shells. • Compare median biomasses at species and community level in warm versus cold period within MIS 22–18. • Bivalve shell biomass response to temperature is not universal. • Decrease in median biomass is observed during the MIS 19 warm period. • Larger species are negatively affected by warming both in terms of relative abundance and biomass. [ABSTRACT FROM AUTHOR]

During the Messinian, the sensitivity of the Mediterranean Basin to ecosystem perturbation was enhanced in response to the progressive restriction of water exchange with the Atlantic Ocean. The widespread deposition of organic-rich layers (i.e. sapropel) during the Messinian testifies the perturbation of the carbon and oxygen cycles; indeed, these sediments were deposited under conditions of oxygen starvation, presumably in response to a periodic deterioration of the thermohaline circulation strength. Disentangling the causes, the effect and magnitude of the thermohaline circulation weakening during the geological past is crucial for better constraining present and near-future deoxygenation dynamics in the Mediterranean region under the current climate warming. For this purpose, we investigate a Messinian sapropel-bearing succession cropping out at Monte dei Corvi (Ancona, central Italy) with mineralogical, petrographic, micropaleontological and stable Carbon and Oxygen isotopic analyses. We show that sapropel layers were deposited in response to an increase of the sea surface buoyancy, which hampered the thermohaline circulation and thus the oxygenation of bottom water, in turn affecting the bioturbating organisms. Within the lithological cycle, the recovery of an efficient thermohaline circulation is recorded by thin packstone layers underlying the marly limestone/marlstone, which record intense bottom currents. The marly limestone/marlstone accumulated during periods of intense primary productivity and organic carbon export to the sea bottom, which promoted bottom hypoxia but not organic matter preservation. We infer that these lithological changes resulted from variations in the Adriatic Deep Water formation system, controlled by precession-driven climatic and oceanographic changes. By integrating previously published Sea Surface Temperature (SST) with new isotopic and mineralogical data, we show that variations in Sea Surface Salinity (SSS) were the leading factor controlling sapropel deposition, minimizing the role of primary productivity. The SSTs characterizing the sapropel deposits are close to the range of those projected in the Eastern Mediterranean at the end of this century under climate warming. In this scenario, future warming will be coupled with SSS increase, which will counteract the density loss provided by temperature, making the bottom deoxygenation in the Eastern Mediterranean abysses unlikely. However, additional forcing, such as winter heat waves and eutrophication, could contribute to negatively affecting the Mediterranean oxygen balance and should be considered in model-based projections. • The Monte dei Corvi recorded the changes in the ADW formation during the Messinian. • The bottom deoxygenation resulted from variations in the freshwater input. • Future deoxygenation in Mediterranean can be provided by productivity or heatwaves. [ABSTRACT FROM AUTHOR]