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The serious consequences of climate warming have increasingly become a globe agenda in recent decades. China has been actively participating in various initiatives to address global climate change and has made commitments to reduce carbon emissions. Although the logistics industry is regarded as the "new driving force of national economic development", its carbon intensity is relatively high. Therefore, whether the logistics industry can develop in a green and low-carbon way is very crucial. This paper takes the green logistics efficiency of China's provincial logistics industry as the research object. The Super-SBM model is used to measure the China's green logistics efficiency, then the general dynamic characteristics is depicted by kernel density analysis. With the GML (Global Malmquist-Luenberger) index model, the reasons for the changes in green logistics efficiency are explained. Finally, Moran's I index is used to analyze the spatial correlation of green logistics efficiency in each province. The results show that the green logistics efficiency in China is at a low level, but with an upward trend. China's green logistics efficiency has a significant positive spatial correlation, showing a zonal pattern of high in the east and low in the west, and a polarization phenomenon. In addition, the bottleneck of the overall development of green logistics efficiency in China depends on the level of green technology. Furthermore, the results also imply that green technology advancement is an inherent key factor for green logistics efficiency to achieve growth. [ABSTRACT FROM AUTHOR]

The 2015 Paris Agreement has set out the climate change target of limiting global warming to 1.5 °C, which poses a serious challenge to countries to reduce emissions. As the world's largest carbon emitter, promoting the realization of the "dual-carbon" goal is the key to realizing China's green transformation and high-quality development. Chinese asset managers play active roles in the capital market as an important channel of asset allocation. Currently, the vast majority of Chinese asset managers hold high percentages of high-carbon industries in their portfolios, and lack quantitative data of their carbon footprints embodied in equity investments, which faces huge carbon-related risks. Therefore, it's an urgent need to comprehensively and scientifically measure financed emissions of Chinese asset managers, which is of great significance for asset managers' carbon risk management and sustainable investment. This paper develops a detailed inventory of carbon emissions for equity portfolios managed by Chinese asset managers from 2010 to 2020, which stands as a pivotal reference for in-depth analysis of emission characteristics. [ABSTRACT FROM AUTHOR]

This paper studies climate change impacts on total factor productivity (TFP) in China using economic and climatic data for provincial capital cities and municipalities from 1998 to 2017. We employ a novel nonparametric quantile method to decompose historical temperature data into multiple temperature quantiles, which are then used in our regression analysis to avoid estimation bias caused by seasonal heterogeneity of temperatures across China. Specifically, we create three temperature quantiles for each city to represent their extremely high temperatures in summer, extremely low temperatures in winter, and mild temperatures in spring and fall. In general, we find that a warming climate has a significant negative impact on TFP in the long-run, while in the short term, only increases in extreme temperatures exert significant negative effects on TFP growth. However, the temperature effects on TFP vary substantially across coastal capital cities, inland capital cities, and municipalities due to their differences in geography, development levels, and political positions. Finally, our results are robust when spatial spillover, temporal lagging, and labor intensity effects are taken into account. [ABSTRACT FROM AUTHOR]

The increased growth of vegetation has the potential to slow global climate warming. Therefore, analyzing and predicting the response assessment of Chinese vegetation to climate change is of great significance to studies of global warming. In this paper, we examine the spatiotemporal dynamics of vegetation leaf area index (LAI) values in China from 1981 to 2017 and their correlations with meteorological (hydrothermal) factors based on trend analysis and correlation analysis. We further construct an LAI prediction model based on hydrothermal conditions. The climate data obtained under different scenarios in the CMIP5 and CMIP6 climate models were used to predict the dynamic change trend of vegetation LAI from 2021 to 2100. The results show that most areas of China (72.82%) showed an improving trend in vegetation LAI from 1981 to 2017, during which the annual average LAI value increased at a rate of 0.0029 year−1. Vegetation LAI in China was significantly correlated with climatic factors (temperature, precipitation, and evapotranspiration), and the LAI prediction model constructed based on hydrothermal conditions had a high accuracy (Pearson's Cor value is 0.9729). From 2021 to 2100, approximately 2/3 of China's vegetation LAI area showed an improvement trend, and the impact of climate change on vegetation LAI predictions under the high emission scenario was greater than that under the low emission scenario. This research can provide a basis for studies on the climatic drivers of vegetation change and the global vegetation dynamic model. [ABSTRACT FROM AUTHOR]

To cope with climate change, it is of great importance to describe the temporal and spatial evolution of climate change vulnerability and its driving factors. Therefore, this paper establishes a comprehensive index of vulnerability to climate change based on the vulnerability scoring diagram (VSD) framework. Moran's I index is used to study the spatial evolution characteristics of vulnerability, and spatial regression analysis is used to explore the factors influencing the spatial distribution of vulnerability. The results show that (1) the climate change vulnerability of China has decreased over time, and the sensitivity state is relatively stable; however, the annual change in exposure and adaptive capacity is significant. (2) The western region of China is more vulnerable than the eastern region, and the most vulnerable provinces are Guizhou and Gansu. (3) The regional vulnerability is generally in a significant spatial agglomeration state. (4) Finally, the driving factors of the spatial distribution of climate change vulnerability include forest coverage, the urban-rural income gap and information technology. These recommendations provide detailed discussions and scientific information for mitigating global warming and formulating long-term emission reduction targets, thereby optimizing resource allocation and providing spatial governance directions for the formulation of adaptation policies. [ABSTRACT FROM AUTHOR]

As an important cause of global warming, CO2 concentrations and their changes have aroused worldwide concern. Establishing explicit understanding of the spatial and temporal distributions of CO2 concentrations at regional scale is a crucial technical problem for climate change research. High accuracy surface modeling (HASM) is employed in this paper using the output of the CO2 concentrations from weather research and forecasting-chemistry (WRF-CHEM) as the driving fields, and the greenhouse gases observing satellite (GOSAT) retrieval XCO2 data as the accuracy control conditions to obtain high accuracy XCO2 fields. WRF-CHEM is an atmospheric chemical transport model designed for regional studies of CO2 concentrations. Verified by ground- and space-based observations, WRF-CHEM has a limited ability to simulate the conditions of CO2 concentrations. After conducting HASM, we obtain a higher accuracy distribution of the CO2 in North China than those calculated using the classical Kriging and inverse distance weighted (IDW) interpolation methods, which were often used in past studies. The cross-validation also shows that the averaging mean absolute error (MAE) of the results from HASM is 1.12 ppmv, and the averaging root mean square error (RMSE) is 1.41 ppmv, both of which are lower than those of the Kriging and IDW methods. This study also analyses the space-time distributions and variations of the XCO2 from the HASM results. This analysis shows that in February and March, there was the high value zone in the southern region of study area relating to heating in the winter and the dense population. The XCO2 concentration decreased by the end of the heating period and during the growing period of April and May, and only some relatively high value zones continued to exist. [ABSTRACT FROM AUTHOR]

In recent years, climate and environment changes since the Little Ice Age have become a focus in modern research. The paper selected the sediment (77 cm) of Sihu Lake, which was located in Guilin, southern China, as the research object and analyzed the karst wetland environmental changes within nearly 450 years. According to the vertical profile of indicators and geochemical elements in sediment core, the regional environmental evolution was divided into four stages. The former two stages were mainly influenced by Little Ice Age (1562–1895). The third stage climate has changed slowly. The fourth stage was mainly affected by human activities and global warming. The factor analysis of geochemical elements indicated that karst wetland regional environmental change was affected by four major factors. In the 53–77 cm stage (1562–1703), F1 (erosion factor), F2 (watershed runoff and diagenesis factor) and F3 (regional background factor) were reduced, indicating that it was in cold and dry stage of Little Ice Age. In the 20–53 cm stage (1703–1895), F1 and F2 increased, indicating that it was in cold and wet stage of Little Ice Age. In the 4–20 cm stage (1895–1987), F1, F2 and F4 (human activity factor) increased slowly, indicating that the climate was affected by global warming and more precipitation. In the 0–4 cm stage (1987–2007), F1 and F2 reduced and F4 increased, indicating the reduced precipitation, rising temperature and more impact of human activities. In addition, it was proposed that the Little Ice Age in Guilin District in southern China started in the 1560s and lasted until the 1895s or so. [ABSTRACT FROM AUTHOR]

Global warming is now recognized as a significant threat to sustainable development on an international scale. One of the key challenges in mounting a global response to it is the seeming unwillingness of the fastest growing economies such as China and India to sign a treaty that limits their emissions. The aim of this paper is to examine the differential incentives of countries on different trajectories of capital growth. A benchmark dynamic game to study global warming, introduced in Dutta and Radner (J Econ Behav Organ, ), is generalized to allow for exogenous capital accumulation. It is shown that the presence of capital exacerbates the 'tragedy of the common'. Furthermore, even with high discount factors, the threat of reverting to the inefficient 'tragedy' equilibrium is not sufficient to deter the emissions growth of the fastest growing economies-in contrast to standard folk theorem like results. However, foreign aid can help. If the slower growth economies-like the United States and Western Europe-are willing to make transfers to China and India, then the latter can be incentivized to cut emissions. Such an outcome is Pareto improving for both slower and faster growth economies. [ABSTRACT FROM AUTHOR]

In the context of ongoing global warming, understanding the East Asian Summer Monsoon (EASM) dynamics is of great significance for predicting future climate changes. This study reconstructed the mid-Holocene precipitation variations on the basis of pollen data obtained from Taojiacun section in the Luoyang Basin within the Central Plains of China. Our research results show that the region experienced three dry intervals during the data-covering period (~ 8.08 to ~ 4.76 cal. kyr BP): ~8.08 to ~ 7.35, ~ 6.42 to ~ 5.59, and ~ 4.94 to ~ 4.76 cal. kyr BP. The intervened were two wet intervals: ~7.35 to ~ 6.42 and ~ 5.59 to ~ 4.94 cal. kyr BP. The chronological correspondence between drier (wetter) intervals in the Luoyang Basin and warmer (cooler) intervals in the western Tropical Pacific implies that the north-south shifts of the Western Pacific Subtropical High (WPSH), driven by the western Tropical Pacific Sea Surface Temperature (SST), regulated the positions of the EASM-related rain-belt during the data-covering period. We compared the mean annual precipitation (Pann) sequence from Taojiacun section with those from the southern and northern neighboring areas. With a full consideration of chronological uncertainties and sampling resolution differences, it can be generalized that those drier (wetter) intervals in the Luoyang Basin within the Central Plains of China were broadly correspondent with those drier (wetter) intervals expressed in the sequences of the southern neighboring areas (i.e., the middle and lower reaches of the Yangtze River with an addition of the Huai River Basin). It means that the changes in precipitation in the Central Plains was most likely coincident with that in the southern neighboring areas during the data-covering period (~ 8.08 to ~ 4.76 cal. kyr BP). [ABSTRACT FROM AUTHOR]

We evaluated the potential impact of future climate change on spring maize and single-crop rice in northeastern China (NEC) by employing climate and crop models. Based on historical data, diurnal temperature change exhibited a distinct negative relationship with maize yield, whereas minimum temperature correlated positively to rice yield. Corresponding to the evaluated climate change derived from coupled climate models included in the Coupled Model Intercomparison Project Phase 5 (CMIP5) under the Representative Concentration Pathway 4.5 scenario (RCP4.5), the projected maize yield changes for three future periods [2010-39 (period 1), 2040-69 (period 2), and 2070-99 (period 3)] relative to the mean yield in the baseline period (1976-2005) were 2.92%, 3.11% and 2.63%, respectively. By contrast, the evaluated rice yields showed slightly larger increases of 7.19%, 12.39%, and 14.83%, respectively. The uncertainties in the crop response are discussed by considering the uncertainties obtained from both the climate and the crop models. The range of impact of the uncertainty became markedly wider when integrating these two sources of uncertainty. The probabilistic assessments of the evaluated change showed maize yield to be relatively stable from period 1 to period 3, while the rice yield showed an increasing trend over time. The results presented in this paper suggest a tendency of the yields of maize and rice in NEC to increase (but with great uncertainty) against the background of global warming, which may offer some valuable guidance to government policymakers. [ABSTRACT FROM AUTHOR]

The mid-Pliocene warm period was the most recent geological period in Earth's history that featured long-term warming. Both geological evidence and model results indicate that East Asian summer winds (EASWs) strengthened in monsoonal China, and that East Asian winter winds (EAWWs) weakened in northern monsoonal China during this period, as compared to the pre-industrial period. However, the corresponding mechanisms are still unclear. In this paper, the results of a set of numerical simulations are reported to analyze the effects of changed boundary conditions on the mid-Pliocene East Asian monsoon climate, based on PRISM3 (Pliocene Research Interpretation and Synoptic Mapping) palaeoenvironmental reconstruction. The model results showed that the combined changes of sea surface temperatures, atmospheric CO concentration, and ice sheet extent were necessary to generate an overall warm climate on a large scale, and that these factors exerted the greatest effects on the strengthening of EASWs in monsoonal China. The orographic change produced significant local warming and had the greatest effect on the weakening of EAWWs in northern monsoonal China in the mid-Pliocene. Thus, these two factors both had important but different effects on the monsoon change. In comparison, the effects of vegetational change on the strengthened EASWs and weakened EAWWs were relatively weak. The changed monsoon winds can be explained by a reorganization of the meridional temperature gradient and zonal thermal contrast. Moreover, the effect of orbital parameters cannot be ignored. Results showed that changes in orbital parameters could have markedly affected the EASWs and EAWWs, and caused significant short-term oscillations in the mid-Pliocene monsoon climate in East Asia. [ABSTRACT FROM AUTHOR]

The overdevelopment of urban area has decreased the city's ground permeability and increased its surface runoff. Moreover, the urban area existing flood control system meets the high risk and new challenge for water resource management due to global warming and climate change. A huge idle raft foundation space of existing buildings in urban area is found to be practicable solution for urban flood control systems. Through the operation model using street block and raft foundation space in urban area can effectively reduce peak runoff during typhoon seasons and extreme rainfall periods. This study selected a certain street block in Taipei City and 47 typical typhoons as validation, and constructed a Street Block-Raft Foundation flood control model (SB-RF model). Firstly, the optimal solution for reducing peak runoff for the 47 typhoons was obtained using Linear Programming. Data from the optimal solution and Back Propagation Neural Network were then used to simulate the SB-RF model flood control. This paper not only demonstrates the effectiveness of proposed model in controlling urban floods, but establishes an expected average peak runoff reduction rate and proposes a methodology for optimizing flow controls. Results are proved to be useful as reference for urban flood control for urban area such as Taipei City during typhoon season. [ABSTRACT FROM AUTHOR]

Global climate change and its possible ecological consequences have become the focused issue (IPCC, 2007; Mann et al., 2008; Ding et al., 2009). The Holocene contains the analogous characteristic of future climatic change and the continuous agriculture activity, providing the ideal “similar pattern” for studying the climate change and human adaption and impact in the future. Based on the recent studies of stalagmite, ice core, ocean, and lake etc., the paper introduces the new progress in the Holocene climate and agriculture research in China as follows: (1) Discuss the variability, amplitude, and unstable characteristic of climate, as well as the abrupt events and mechanisms of climate. (2) Analyze the botanical index records for studying the early agriculture. (3) Review the agricultural origin, expanding, and development. (4) Reveal the style and intensity of early agriculture and understand the agricultural impact and adaption to the environmental changes. (5) Introduce ongoing research projects in China and emphasize the significance of increasing the dating precision and the indicative effectiveness of proxies. (6) Realize how the ecosystem and environmental factors respond to the increasing temperature process, understand how the human adapt to the rapid climate change, and provide the scientific basis for assessing the effects of climate change and the human adaption in the future. [ABSTRACT FROM AUTHOR]

This paper provides new evidence of regional warming trends from local Chinese observations covering the period 1951–2010. We used satellite-derived land data and weighted urban and rural temperature records (a weighted method) and estimate the regional warming trend, which involves natural climate change and human impact. The annual warming rate over the whole of China is 0.21 ± 0.02 °C/decade. The seasonal warming is 0.30 ± 0.05 °C/decade (Winter), 0.24 °C ± 0.03 °C/decade (Spring); 0.16 ± 0.02 °C/decade (Summer) and 0.21 ± 0.03 °C/decade (Autumn). The mean warming trend is lower than previous estimates (e.g. NMIC, CRU-China) using un-weighted methods (arithmetic average of all records). The warming difference between the weighted and un-weighted accounts for 27 % (12 %) of the NMIC (CRU-China) un-weighted estimate on the total warming. This indicates that previous estimations overestimated a regional warming trend. The differences can be partly attributed to the weighting of the urban effect which is taken into consideration in this study, resulting in a much slower temperature increase. Spatially, the northern part of China shows a larger difference than the south especially for winter and spring. We argue that it is of importance to take into consideration the influence of urban land-use change to improve the physical understanding of surface warming in China over past decades. [ABSTRACT FROM AUTHOR]

Understanding the seasonal behaviour of a subtropical forest and its inter-annual variation is crucial to understanding and monitoring its ecosystem function in the context of global warming. Based on the Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index dataset, a wavelet transform method was used to investigate the inter-annual variations of vegetation phenology in a subtropical mountain and hill region in Fujian, China, during 2001-2010. The results show a distinct inter-annual variation of vegetation phenology related to climate variability even if most areas presented non-significant trends. The start dates significantly advanced and end dates delayed in 2003 and 2008, due to anomalously warm conditions. There was generally a gradient of increasing start dates, and earlier end dates of vegetation growing season, due to colder temperatures at higher altitudes. However, the altitudinal phenology relationship also depends on its corresponding rainfall conditions. Earlier start dates were observed at higher altitudes during rainfall deficit years such as 2008, which coincides with relatively abundant rainfall at higher altitudes. This paper reveals that vegetation phenology was coupled with altitudinal gradient, with distinct responses at different combinations of alternate temperature and precipitation conditions variability. [ABSTRACT FROM AUTHOR]

Challenged by insufficient water resources and by degraded water quality caused by widespread pollution, China faces an imbalance between the supply and the demand of water for supporting the rapid social and economic development while protecting the natural environment and ecosystems. Climate change is expected to further stress freshwater resources and widen the gap between the demand for and supply of water. As a legacy of the earlier planned economy, water resources management has been primarily supply-driven, which largely fails to account for the economic nature of water resources in relation to their natural characteristics. This paper presents a historical perspective on the water resources management policies and practices in China, and recommends demand management and pollution control as key measures for improving water resources management to adapt to climate change based on the current political, socio-economic and water resources conditions. The past and future impacts of climate change on water resources in China and the general adaptation strategies are also presented. How demand management through increasing water use efficiency, improving water rights and rights trade, and effective regulation enforcement, along with pollution control could improve China's water resources management are discussed in details. Ultimately, China should develop a sustainable water resources management strategy based on both supply- and demand-side management options to make the limited water supplies meet the demands of economic development, social well-being and the conservation of ecosystems in the context of global climate change. [ABSTRACT FROM AUTHOR]

Global warming tends to be the major characteristics of the dramatic global climate change. To deal with these changes, the impact of reducing greenhouse gas (GHG) emission on Chinese future economic and social development has to be assessed. In this paper, a Regional Integrated model of Climate and the Economy (RICE), which is well known and accepted widely, has been used for Chinese economic assessment of climate change after introduction, assimilation and verification. Based on a sensitivity analysis of technical parameters in the RICE model and constrained targets proposed for energy saving and emissions reduction technological advance programs of China from 2000 to 2050, the economic impact of the programs is examined. The results indicate that when technology advances, Chinese CO2 emission, climate loss, and the growth rate of atmospheric CO2 concentration and temperature will all decrease. It is assumed that in 2010, the CO2 emission is 20% lower than in 2005, CO2 emission in 2050 would only double the level in 2000, the accumulative CO2 emission would be decreased by 12.4 GtC, and the atmospheric CO2 concentration and temperature in 2050 would reduce by 35 GtC and 0.04°C respectively from 2000 to 2050. The accumulative climate loss from 2000 to 2050 will drop down by 4.6 billion dollar, which only accounts for 6% of the global total benefits. However, the economic benefit the developed countries will obtain is 10 times that for China under such a technological advance scenario. The decrease of the CO2 emission control rate is 1% in cooperation policy while 4.6% in non-cooperation policy, which would relieve China's burden in the control of CO2 total emission and thereby benefit China in participation of the international cooperation for CO2 emission reduction. [ABSTRACT FROM AUTHOR]

Monthly precipitation data of 42 rain stations over the Pearl River basin for 1960–2005 were analyzed to classify anomalously wet and dry conditions by using the standardized precipitation index (SPI) and aridity index ( I) for the rainy season (April–September) and winter (December–February). Trends of the number of wet and dry months decided by SPI were detected with Mann-Kendall technique. Furthermore, we also investigated possible causes behind wet and dry variations by analyzing NCAR/NCEP reanalysis dataset. The results indicate that: (1) the Pearl River basin tends to be dryer in the rainy season and comes to be wetter in winter. However, different wetting and drying properties can be identified across the basin: west parts of the basin tend to be dryer; and southeast parts tend to be wetter; (2) the Pearl River basin is dominated by dry tendency in the rainy season and is further substantiated by aridity index ( I) variations; and (3) water vapor flux, moisture content changes in the rainy season and winter indicate different influences of moisture changes on wet and dry conditions across the Pearl River basin. Increasing moisture content gives rise to an increasing number of wet months in winter. However, no fixed relationships can be observed between moisture content changes and number of wet months in the rainy season, indicating that more than one factor can influence the dry or wet conditions of the study region. The results of this paper will be helpful for basin-scale water resource management under the changing climate. [ABSTRACT FROM AUTHOR]

Coral reefs worldwide are becoming increasingly and detrimentally impacted upon by a variety of factors including significant climate changes, such as global warming and increased El Niño-Southern Oscillation activity. Generally, the persistence of coral reefs, especially at low-latitudes, is governed, in part, by sea surface temperatures not exceeding the critical limit (∼30°C) at which mass mortality can occur. Thus, it is thought that corals living at high-latitudes (i.e., currently cooler sea surface temperatures) will likely respond more favourably to hypothesized future temperature increases than corals living at low-latitudes (i.e., currently warmer sea surface temperatures). Consequently, high-latitude coral communities may have the potential to act as regions of refugia for many coral species in the face of potential future global warming. The Daya Bay (22°31'-22°50'N), northern South China Sea, contains several high-latitude non-reefal coral communities and represents one of the most northerly distributions of scleractinian corals within the region. Significantly, Daya Bay has experienced dramatic warming in both air and sea surface temperatures throughout the past 50 years. In this paper, we analyze 25 years of change in the Daya Bay coral communities, based both on historic surveys and our latest 2006-2008 regional ecological surveys. Our results suggest that, contrary to predictions, there have been significant declines in coral cover within the Daya Bay during the past 25 years (i.e., 76.6% coral cover in 1983/1984 to only 15.3% coral cover by 2008). Such changes also reflect a significant shift in the most abundant coral species, from Acropora pruinosa to Favites abdita. Most of the modern coral communities became established between 15 and 30 years ago, corresponding to a period of increased winter sea surface temperature. However, very few colonies have become established within the last 15 years, despite a more intense period of warming. By taking into account additional factors, we hypothesize that direct anthropogenic impacts, rather than climatic events, have both restricted the development, and drove the decline, of Daya Bay coral communities in the last 15 years. The Daya Bay has also been subjected to occasional extreme cold events during the past 50 years, with the most recent occurring in early 2008 (13 January-13 February). During the 2008 cold event, the lowest air temperature reaches only 6.6°C, and the mean sea surface temperature for February fall to <14°C, including six continuous days at 12.3°C. Significantly, the sea surface temperatures fall below the hypothesized critical lower temperature threshold (∼13°C) that commonly leads to mass mortality in scleractinian coral communities. Surprisingly, our coral community surveys, conducted both before (August 2007) and after (late February 2008) the extreme 2008 cold event, demonstrate that the Daya Bay coral ecosystems are barely impacted upon during the cold period. Those observations suggest that the Daya Bay scleractinian coral communities have developed adaptations to low sea surface temperatures. Overall, our data support the hypothesis that high-latitude coral communities, such as Daya Bay, have the potential to act as areas of refugia for scleractinian corals in the advent of potential future global warming. [ABSTRACT FROM AUTHOR]

This paper analyzes the statistics of faults in a transmission and distribution networks in central China, unveils long-term autocorrelation and power law distribution of power system faults, which indicates that power system fault has self-organized criticality (SOC) feature. The conclusion is consistent with the power systems data in 2008 with ice storm present. Since power systems cover large areas, climate is the key factor to its safety and stability, In-depth analysis shows that the SOC of atmosphere system contributes much to that of power system faults. Extreme climate will be more intense and frequent with global warming, it will have more and more impact upon power systems. The SOC feature of power system faults is utilized to develop approaches to facilitate power systems adaptation to climate variation in an economical and efficient way. [ABSTRACT FROM AUTHOR]

Estimates of forest vegetation carbon storage in China varied due to different methods used in the assessments. In this paper, we estimated the forest vegetation carbon storage from the Fourth Forest Inventory Data (FFID) in China using a modified volume-derived method. Results showed that total carbon storage and mean carbon density of forest vegetation in China were 3.8 Pg C (about 1.1% of the global vegetation carbon stock) and 41.32 Mg/ha, respectively. In addition, based on linear multiple regression equation and factor analysis method, we analyzed contributions of biotic and abiotic factors (including mean forest age, mean annual temperature, annual precipitation, and altitude) to forest carbon storage. Our results indicated that forest vegetation carbon storage was more sensitive to changes of mean annual temperature than other factors, suggesting that global warming would seriously affect the forest carbon storage. [ABSTRACT FROM AUTHOR]

Global warming has exacerbated the instability of the climate and has led to the frequent occurrence of extreme cold and warm events. The complex geography of the high-latitude region of China's monsoon-continental transition zone makes it extremely sensitive to climate response, understanding temperature changes over long periods of time is crucial to revealing trends in climate change trends. In this study, we constructed a standardized tree-ring width chronology of Korean spruce growing in this area from 1845 to 2016 and used it to analyzed the response of the radial growth of Korean spruce to climatic factors such as temperature and precipitation. The results show that the annual mean temperature was the dominant climatic factor affecting the growth of Korean spruce. Hence, we reconstructed the annual mean temperature series of this region spanning the past 172 years. The analysis results show that the study area experienced five warm periods and five cold periods in the past 172 years. Cold years were dominant before 1960s, while temperature continuously rose and changed drastically in the early twenty-first century. The reconstructed annual mean temperature series has variability cycles of 3a, 7a, 10–12a, 15–22a and 30–40a. The results of this reconstruction enrich the tree-ring database in the representative regions of the monsoon-continental climate transition zone in China and provide a reference for systematically understanding the climate change patterns in the representative regions of the transition zone. [ABSTRACT FROM AUTHOR]

It is well accepted that the phenology of insects whose life activities are closely related to temperature is changing in response to global climate warming. To investigate the impacts of climate warming on the phenology of Bactrocera dorsalis (Hendel) across large temporal and spatial scales, this study collected historical data on the occurrence and population dynamic of this pest in China, and systematically explored its phenological responses. The results showed a delayed trend for the dates of first occurrence, end occurrence, population initial growth, and population peak of B. dorsalis in China during 40 years, and the changes of the latter two phenological parameters were significant. The mean temperature in spring and summer were the key climatic factors affecting the occurrence and population growth of B. dorsalis in China, respectively. Moreover, the B. dorsalis data in eastern, southern, central, and southwestern China showed spatial heterogeneity of phenological responses to climate warming at a regional scale. B. dorsalis phenology and their changing patterns with climate warming varied by geographical location. This study provides valuable information for future monitoring, prediction, and prevention of the oriental fruit fly in the context of climate warming. [ABSTRACT FROM AUTHOR]

The corresponding relationships between temperature, precipitation, and polycyclic aromatic hydrocarbon (PAH) concentration in a typical ombrotrophic peatland in Dajiuhu, Shennongjia, were quantitatively characterized by field sampling tests validated with simulation experiments. The PAH concentrations of peat cores in Dajiuhu peatland ranged from 262 to 977 ng·g−1, with a mean value of 536 ± 284 ng·g−1. PAHs were mainly composed of 2–3 ring PAHs, accounting for 31.7% ± 2.00% and 31.7% ± 5.00%, respectively. The concentration of PAHs in peat cores showed a significant decrease with increasing temperature, while the low molecular weight PAHs (LMW-PAHs) were more sensitive to temperature changes compared to the high molecular weight PAHs (HMW-PAHs). Besides, with the increase of quantity and velocity of leaching liquid, PAHs in peat were first transferred in the form of attached large-size particles and then gradually entered the aqueous phase. According to the IPCC projections of global warming, Dajiuhu peatland will release 956 ± 26.3 kg·°C−1 PAHs into gas phase during 2030–2052, and a conservative projection based on local temperature trends showed that 459 ± 12.6 kg·°C−1 PAHs will be released into gas phase by 2047 in Dajiuhu peatland. The projected release fluxes of PAHs in Dajiuhu peatland with precipitation volume and precipitation velocity are 381 ± 201 kg·100 mm−1 and 1052 ± 167 kg·min·mL−1, respectively, which are primarily from peat into particulate and aqueous phase. [ABSTRACT FROM AUTHOR]

Intensifying climate change significantly impacts residential electricity consumption, especially in developing countries, such as China, that are experiencing rapid income growth. By combining meteorological and monthly household consumption survey data, this study explores the response function of residential electricity consumption to temperature in China from a micro perspective. Future residential electricity demands and related CO2 emissions are then forecast under different climate scenarios. Overall, the response function is U-shaped, and one additional day above 34 °C will increase monthly residential electricity consumption by 2.11%. Global warming will more likely increase the electricity burden on low-income groups. There will be notable seasonal changes in electricity demand in the future, and the largest increase will occur in August. The total demand for residential electricity caused by temperature change will show a fluctuating growth trend, from 0.8% and 1% in 2025 to 2% and 2.9% in 2060 under the RCP4.5 scenario and RCP8.5 scenario, respectively; meanwhile, this demand will be accompanied by a cumulative increase in carbon dioxide emissions. [ABSTRACT FROM AUTHOR]

The evident climate jump after 2000 in China may have greatly influenced the production of winter wheat, which is one of the nation's major grain crops. To evaluate the impacts of climate change on winter wheat production and identify the climatic factors primarily responsible, we used daily meteorological data from 2244 stations and integrated indicators to examine the decadal changes in the potential plantable zone (PPZ), growth periods, and climatic suitability for winter wheat in China from 1985 to 1999 and from 2000 to 2014. The results showed the following: (1) The PPZ has decreased by approximately 9%, and the main reason may be the increased frequency of extreme cold events in northern China from 2000 to 2014. (2) In most of the PPZ, the suitable sowing date has been delayed, the potential maturity date has advanced, and total days during the potential growing season have significantly decreased because of the increasing temperature. (3) The suitable area and optimal area of winter wheat have significantly decreased by 9% and 13%, respectively. The changes in climatic suitability are affected by both temperature and radiation in the north, whereas the impact is more from precipitation in the south. The climate may be changing in a direction unsuitable for winter wheat. As global warming and climate extremes intensify in the future, winter wheat production may become more challenging, and adequate measures should be adopted to guarantee reliable and high yields. [ABSTRACT FROM AUTHOR]

The cross-shelf exchange between the Yellow and East China Seas (YECS) with the Kuroshio is important for vorticity, freshwater, and effluence balances of the regional and global oceans, the responses of which to future climate changes are estimated based on Max-Planck coupled model simulations under one historical (20C, 1970–2005) and two representative concentration pathway scenarios of global warming (RCP4.5 and RCP8.5) from 2006 to 2099. The results of the 20C simulation have shown prominent cross-shelf transports in the YECS, with annual mean outflow (OVT) and inflow (IVT) volume transports across the 100 m isobath of 3.97 Sv and 2.86 Sv (1 Sv = 106 m3 s−1), respectively. These annual mean OVTs (and their equivalent IVTs) are projected to increase by 0.42 Sv and 0.48 Sv from 2006 to 2099, at rates of 11.0% and 12.8% from the 2006–2016 means, under the RCP4.5 and RCP8.5 scenarios, respectively. The maximum rates of increase are found in winter to be at 13.2% and 19.9%, respectively. Analyses suggest that the winter monsoon has a long-term southwesterly change, forcing coastal currents to flow into the Yellow Sea along the China coasts to compensate for the increase of the southeastward surface Ekman transport. Due to increases of the Tsushima Strait and upper-layer Kuroshio transports, both the OVT and IVT across the 200 m isobath have onshore changes, resulting in net onshore transport increments of 0.30 Sv and 0.57 Sv under the RCP4.5 and RCP8.5 scenarios, respectively. The enhanced cross-shelf exchanges under future warming scenarios in the YECS suggest their potential importance in carbon transportation and storage. [ABSTRACT FROM AUTHOR]

China has been the world's largest emitter of carbon dioxide since 2006. To achieve the goal of carbon neutrality by 2060, social scientists must become involved in China's deep decarbonization process. However, Chinese social scientists have given little attention to climate change in their bibliometric research. Based on the Chinese Social Sciences Citation Index journal catalog of the four essential social sciences, namely, management, economics, politics, and sociology, we used the China National Knowledge Infrastructure database to quantify the extent to which Chinese social scientists are concerned about climate change. The results showed that from 1978 to 2020, 1179 articles on climate change were published in management, economics, politics, and sociology journals, which represented only 26.8% of the 4397 articles published on pollution in the same journals. Politics journals published the most articles (38.76%), while sociology journals published the fewest (2.37%). Thus, Chinese social scientists rarely considered climate change, mainly because this topic remains controversial in some fields and because of the influence of international politics in addition to the promotion and incentive mechanisms for researchers. We analyzed the keywords and evolution of climate change research in the four social sciences and our results show that social scientists should give greater emphasis to climate change in their research. [ABSTRACT FROM AUTHOR]

Due to global warming, global and regional extreme precipitation events occur frequently, causing severe drought and flood disasters. This has a significant impact on productivity and human life. Therefore, it is of great significance to study the characteristics of extreme precipitation and its spatiotemporal variation. In this study, we investigate the dominant variation patterns of extreme precipitation (EP), which is characterized by indices, and also analyze its potential causes in the Shandong province of China during 1961–2015 using the daily precipitation data from 123 metrological stations. The results show that there has been a dry trend in the Shandong Province in the past 55 years, that is, with the decrease in precipitation, most of the extreme precipitation index has basically showed a downward trend to varying degrees. In particular, the increase in the number of consecutive dry days (CDD) and the decrease in the number of consecutive wet days (CWD) can better explain the drought in this region. After the 1980s, the extreme precipitation index basically showed an upward trend to varying degrees, indicating that extreme precipitation events have shown an increasing trend in recent years. The spatial distribution of each extreme precipitation index generally increased from north to south. The mutation of each extreme precipitation index occurred in the 1970s and 1990s, and there was a main period of 0.9–2.2 years. In terms of influencing factors, the NINO3 area can be used as the critical sea area for the response of extreme precipitation to SSTAs in the Shandong Province. The research results are helpful to understand the temporal and spatial variations of extreme precipitation and have very important reference value for the prediction of and response to climate change and extreme events in the future. [ABSTRACT FROM AUTHOR]

China is the largest source of carbon emissions in the world, and the Chinese iron and steel sector is the main contributor to the growth in greenhouse gas emissions. In addition to excessive greenhouse gas emissions, climate change and global warming have seriously threatened the survival of animals, plants and even humans. To cope with global climate problems, it is our responsibility to establish environment-friendly iron and steel enterprises. In this study, data envelopment analysis (DEA) is used to evaluate the environmental protection performance of China's iron and steel enterprises based on the panel data during 2015–2017. We first establish an environment-related index system for the industry and build a range-adjusted measure model. Then, the global Malmquist productivity index based on DEA is introduced to analyse environmental efficiency and environmental productivity. The results show that most Chinese iron and steel enterprises achieved high environmental efficiency. However, many enterprises exhibited low environmental productivity and especially Shougang Group, HBIS Tangsteel and Anyang Iron and Steel continued to decline from 2015 to 2017. In general, Valin Hengyang and Shaanxi Iron and Steel achieved better performance in environmental protection. Based on the above results, the environmental problems in our country are still very serious. Thus, the government needs to formulate suitable environmental regulations to reduce the gap between the global frontier and contemporaneous frontier over two periods. Furthermore, entrepreneurs should introduce some advanced environmental technologies to improve their technical level and environmental protection level. [ABSTRACT FROM AUTHOR]

There is considerable interest in the potential impact of climate change on wind energy in China. The climate change of near-surface wind energy potential in China under the background of global warming and its association with anthropogenic land-use changes are investigated by calculating the difference in surface wind speeds between the NCEPINCAR reanalysis data and the observations since the re- analysis dataset contains the influence of large-scale climate changes due to greenhouse gases, it is less sensitive to regional surface processes associated with land types. The surface wind data in this study consist of long-term observations from 604 Chinese Roution Meteorological Stations and the NCEPINCAR reanalysis data from 1960-1999. The results suggest that the observed mean wind speeds signif icantly weakened and the near-surface wind power trended downward due to urbanization and other land-use changes in the last 40 years. The mean wind energy weakened by -3.84 W•m-2 per decade due to the influence of anthropogenic land-use change, which is close to the observed climate change (-4.51 W•m-2/1 0 a). [ABSTRACT FROM AUTHOR]

Global warming has accelerated surface water loss around the world. This study investigates in detail the change and attribution of potential evapotranspiration (PET) across China from 1901 to 2100 by the Hargreaves model, based on a 1-km temperature dataset downscaled from the low-spatial-resolution datasets using a Delta downscaling framework. Results showed that (1) relative to 1961–1990, PET increased by 0.62% in the historic period (1901–2017) and 6.43–12.89% for the future period (2018–2100), suggesting considerable future drying for China. Moreover, these increments had strong spatial variations and the largest increases were detected in high-elevation regions; (2) PET over entire China demonstrated a nonsignificant upward trend during the historic period and significant upward trends for the future period. For each period and GCM, significant upward PET trends occupied a much larger percent area than significant downward trends; (3) PET variations during the historic period were most sensitive to mean temperature (TMP), while in the future period it was more sensitive to maximum temperature (TMX), suggesting a change in the primary sensitivity factor due to global warming; (4) minimum temperature (TMN) made the largest contribution (45%) to PET variations during the historic period, while TMX had the largest contribution (36–40%) in the future period. Therefore, the primary contributing factor might transform from TMN to TMX under climate change; and (5) PET variations exhibited strong spatial heterogeneity, detected on fine geographic scales, due to the use of downscaled dataset. Overall, the results present a deep insight for planning coping strategies of global warming in China. [ABSTRACT FROM AUTHOR]

Recent studies have reported a variety of health consequences of climate change. However, the vulnerability of individuals and cities to climate change remains to be evaluated. We project the excess cause-, age-, region-, and education-specific mortality attributable to future high temperatures in 161 Chinese districts/counties using 28 global climate models (GCMs) under two representative concentration pathways (RCPs). To assess the influence of population ageing on the projection of future heat-related mortality, we further project the age-specific effect estimates under five shared socioeconomic pathways (SSPs). Heat-related excess mortality is projected to increase from 1.9% (95% eCI: 0.2–3.3%) in the 2010s to 2.4% (0.4–4.1%) in the 2030 s and 5.5% (0.5–9.9%) in the 2090 s under RCP8.5, with corresponding relative changes of 0.5% (0.0–1.2%) and 3.6% (−0.5–7.5%). The projected slopes are steeper in southern, eastern, central and northern China. People with cardiorespiratory diseases, females, the elderly and those with low educational attainment could be more affected. Population ageing amplifies future heat-related excess deaths 2.3- to 5.8-fold under different SSPs, particularly for the northeast region. Our findings can help guide public health responses to ameliorate the risk of climate change. Global warming is expected to increase mortality due to heat stress in many regions. Here, the authors asses how mortality due to high temperatures changes in China changes for different demographic groups and show that heat-related excess mortality is increasing under climate change, a process that is strongly amplified by population ageing. [ABSTRACT FROM AUTHOR]

Against the background of global warming, extreme agrometeorological events have become more intense and frequent during the growing season of maize (Zea mays L.). In this study, we focused on the five types of extreme agrometeorological events that greatly affect maize production in Northeast China, including chilling injury, drought, rainstorm, frost, and gale. We averaged the actual timing of phenological events from the study agrometeorological stations and divided the maize growing season into four growth stages: emergence—jointing, jointing—flowering, flowering—kernel milk, and kernel milk—physiological maturity. Based on the historical weather data from 1960 to 2017 in the study region, we derived the values of pertinent indices for the five types of study extreme agrometeorological events during the four selected maize growth stages. The results showed that chilling injury and drought were relatively more frequent during the four growth stages of maize from 1960 to 2017 in the Northeast China. As time goes on during the growing season of maize, the spatial coverage of chilling injury, frost, and gale all showed a decreasing trend. By contrast, the spatial coverage of drought showed an increasing trend during the study growth stages of maize. During growth stages of maize, chilling injury was the main extreme agrometeorological event before the 2000s, while drought became the main extreme agrometeorological event after the 2000s. Identifying the main extreme climate events that could cause yield loss is imperative, and it is important for farmers to acknowledge ongoing changes in these extreme climate events in order to take preventive measures if necessary. [ABSTRACT FROM AUTHOR]

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Background: Global warming has brought many negative impacts on terrestrial ecosystems, which makes the vulnerability of ecosystems one of the hot issues in current ecological research. Here, we proposed an assessment method based on the IPCC definition of vulnerability. The exposure to future climate was characterized using a moisture index (MI) that integrates the effects of temperature and precipitation. Vegetation stability, defined as the proportion of intact natural vegetation that remains unchanged under changing climate, was used together with vegetation productivity trend to represent the sensitivity and adaptability of ecosystems. Using this method, we evaluated the vulnerability of ecosystems in Southwestern China under two future representative concentration pathways (RCP 4.5 and RCP 8.5) with MC2 dynamic global vegetation model. Results: (1) Future (2017–2100) climate change will leave 7.4% (under RCP 4.5) and 57.4% of (under RCP 8.5) of areas under high or very high vulnerable climate exposure; (2) in terms of vegetation stability, nearly 45% of the study area will show high or very high vulnerability under both RCPs. Beside the impacts of human disturbance on natural vegetation coverage (vegetation intactness), climate change will cause obvious latitudinal movements in vegetation distribution, but the direction of movements under two RCPs were opposite due to the difference in water availability; (3) vegetation productivity in most areas will generally increase and remain a low vulnerability in the future; (4) an assessment based on the above three aspects together indicated that future climate change will generally have an adverse impact on all ecosystems in Southwestern China, with non-vulnerable areas account for only about 3% of the study area under both RCPs. However, compared with RCP 4.5, the areas with mid- and high-vulnerability under RCP 8.5 scenario increased by 13% and 16%, respectively. Conclusion: Analyses of future climate exposure and projected vegetation distribution indicate widespread vulnerability of ecosystems in Southwestern China, while vegetation productivity in most areas will show an increasing trend to the end of twenty-first century. Based on new climate indicators and improved vulnerability assessment rules, our method provides an extra option for a more comprehensive evaluation of ecosystem vulnerability, and should be further tested at larger spatial scales in order to provide references for regional, or even global, ecosystem conservation works. [ABSTRACT FROM AUTHOR]

Projecting regional rainfall changes in a warmer climate attracts ongoing attention. However, large uncertainty still exists in multi-model projection. In this study, we introduce a bias-corrected method to correct the multi-model projection of changes in East Asian summer monsoon (EASM) rainfall based on the historical and RCP8.5 runs of 25 models from phase 5 of Coupled Model Intercomparison Project. Firstly, the total rainfall changes are separated into the thermodynamic component due to increased specific humidity and the dynamic component due to circulation changes. The thermodynamic component is corrected using the observed present-day rainfall and the increase rate of specific humidity based on the wet-get-wetter mechanism. On the other hand, the dynamic component with the circulation changes is corrected based on a "spatial emergent constraint" method, which is further validated by the perfect model approach. Together, these corrections give an integrated projection for EASM rainfall changes under global warming. Such an approach can improve the signal-to-noise ratio of projection effectively, from the original 0.73 of the multimodel mean to around 1.9. The corrected projection of EASM rainfall changes shows a pronounced increase in southern China, the northwest Pacific and a belt from northern China to northeastern China, and a weak increase in other EASM regions. [ABSTRACT FROM AUTHOR]

Climate change seriously affects habitat suitability for coldwater fish. Amur whitefish (Coregonus ussuriensis) is a commercially important coldwater fish species found in northeast China that is particularly sensitive to water temperature. We use water temperature models for Songhua (Harbin to Yilan) and Mayi rivers to predict habitat suitability for Amur whitefish and other coldwater fish species during the months of July and August in 2014 and 2100—2 months during which river temperatures can reach extremes. The predict-results showed that fish habitat was to deteriorate over time, and to be less suitable for survival of coldwater fish species in 2100 than that in 2014. Under scenario RCP4.5 (Representative Concentration Pathway 4.5), the time period during which habitat for Amur whitefish was unsuitable increased continually; under scenario RCP8.5 (Representative Concentration Pathway 8.5), Amur whitefish might even disappear from the river basin. A significant increase in river water temperature will compromise coldwater fish survival and possibly lead to their disappearance. Practical measures to control greenhouse gas emissions and reduce the impact of global warming on aquatic ecosystems must be taken. [ABSTRACT FROM AUTHOR]

Based on daily mean temperature data from 32 meteorological stations in the Qinling Mountains (QMs) of China, we analyzed the characteristics and differences of the spatiotemporal changes in the climatic growing season (CGS) in the QMs from 1964 to 2015. Our results are as follows. First, over the past 52 years, the temperature of the QMs significantly increased at a mean rate of 0.22 °C/decade (P < 0.01) in over 98.04% of the area. Significant north–south spatial differences were observed in temperature changes; also, significant differences in the temperature changing trends were observed before and after the abrupt change in temperature. Second, the spatial distributions of the mean growing season start (GSS), end (GSE), and length (GSL) in the QMs varied based on regional differences in latitude and topography. Notably, the GSS, GSE, and GSL were gradually delayed, advanced, and shortened, respectively, as latitude and elevation increased. After the abrupt change in temperature, whether it is in the NSQM (northern slopes of the QMs) or the SSQM (southern slopes of the QMs), the GSS, GSE, and GSL expanded into high-elevation areas. Third, over the past 52 years, the GSS in the QMs exhibited a significant advancing trend of 2.7 days/decade, the GSE was delayed at a rate of 0.66 days/decade, and the GSL displayed a significant extension of 3.36 days/decade. Before the abrupt change in temperature, the GSS, GSE, and GSL exhibited non-significant changing trends; however, the trends in the GSS, GSE, and GSL were more significant after the abrupt change than before. Fourth, the GSS, GSE, and GSL trends in the QMs were significantly different in the NSQM and SSQM regions. After the abrupt change, the GSS, GSE, and GSL trends along the NSQM were more significant than those along the SSQM. [ABSTRACT FROM AUTHOR]

Precipitation and temperature in freeze–thaw agricultural area have different patterns under global warming. In this study, a statistical relationship between large-scale changes in climate variables and local weather data was built by applying an automated statistical downscaling (ASD) model in the Sanjiang Plain in China. We evaluated the prediction ability of the ASD model in terms of spatial–temporal changes in freeze–thaw agricultural area, and the temperature and precipitation changes in the twenty-first century under the representative concentration pathway 4.5 (RCP4.5) scenario were estimated. The results revealed that the explained variances in temperature were higher than 0.93 during the calibration and verification periods, which demonstrated good simulation capacity. The R2 of precipitation was acceptable due to the randomness and complexity of daily precipitation. Based on the Geophysical Fluid Dynamics Laboratory Earth System Model with the Generalized Ocean Layer Dynamics component (GFDL-CM3), the regional climate simulation provided good predictions. By 2100, the average, maximum and minimum temperatures in this area could increase by 2.0–2.5 °C, 2.5 °C and 2.5–4.0 °C, respectively. In terms of the spatial distribution, temperatures could increase faster in the northern region and slower in the central and southern regions. The warming trends in summer and winter were more significant than those in spring and autumn. There was no significant change in annual precipitation in the twenty-first century (increased approximately 10 mm by 2100). Precipitation decreased obviously in July and August (approximately 0.4 mm/day), and other months showed an increasing trend (approximately 0.5–0.9 mm/day). There will be large spatial variation of precipitation in the future changes. The results could serve as a reference for assessing non-point source pollution and agricultural management. [ABSTRACT FROM AUTHOR]

This study investigates observed and modeled contributions of global sea surface temperature (SST) to China winter climate trends in 1960-2014, including increased precipitation, warming through about 1997, and cooling since then. Observations and Atmospheric Model Intercomparison Project (AMIP) simulations with prescribed historical SST and sea ice show that tropical Indian Ocean (TIO) warming and increasing rainfall causes diabatic heating that generates a tropospheric wave train with anticyclonic 500-hPa height anomaly centers in the TIO or equatorial western Pacific (TIWP) and northeastern Eurasia (EA) and a cyclonic anomaly over China, referred to as the TIWP-EA wave train. The cyclonic anomaly causes Indochina moisture convergence and southwesterly moist flow that enhances South China precipitation, while the northern anticyclone enhances cold surges, sometimes causing severe ice storms. AMIP simulations show a 1960-1997 China cooling trend by simulating increasing instead of decreasing Arctic 500-hPa heights that move the northern anticyclone into Siberia, but enlarge the cyclonic anomaly so it still simulates realistic China precipitation trend patterns. A separate idealized TIO SST warming simulation simulates the TIWP-EA feature more realistically with correct precipitation patterns and supports the TIWP-EA teleconnection as the primary mechanism for long-term increasing precipitation in South China since 1960. Coupled Model Intercomparison Project (CMIP) experiments simulate a reduced TIO SST warming trend and weak precipitation trends, so the TIWP-EA feature is absent and strong drying is simulated in South China for 1960-1997. These simulations highlight the need for accurately modeled SST to correctly attribute regional climate trends. [ABSTRACT FROM AUTHOR]

Understanding the temporal variations of extreme floods that occur in response to climate change is essential to anticipate the trends in flood magnitude and frequency in the context of global warming. However, long-term records of paleofloods in arid regions are scarce, thus preventing a thorough understanding of such events. In this study, a reconstruction of paleofloods over the past 300 years was conducted through an analysis of grain sizes from the sediments of Kanas Lake in the Altay Mountains of northwestern China. Results showed that grain parameters and frequency distributions can be used to infer possible abrupt environmental events within the lake sedimentary sequence, and two extreme flood events corresponding to ca. 1736-1765 AD and ca. 1890 AD were further identified based on canonical discriminant analysis (CDA) and coarse percentile versus median grain size (C-M) pattern analysis, both of which occurred during warmer and wetter climate conditions by referring to tree-ring records. These two flood events are also evidenced by lake sedimentary records in the Altay and Tianshan mountains. Furthermore, through a comparison with other records, the flood event from ca. 1736-1765 AD in the study region seems to have occurred in both the arid central Asia and the Alps in Europe, and thus may have been associated with changes in the North Atlantic Oscillation (NAO) index. [ABSTRACT FROM AUTHOR]

The distribution and variations of permafrost in the Xidatan region, the northern permafrost boundary of the Qinghai-Tibet Plateau, were examined and analyzed using ground penetrating radar (GPR), borehole drilling, and thermal monitoring data. Results from GPR profiles together with borehole verification indicate that the lowest elevation limit of permafrost occurrence is 4369 m above sea level in 2012. Compared to previous studies, the maximal rise of permafrost limit is 28 m from 1975 to 2012. The total area of permafrost in the study region has been decreased by 13.8%. One of the two previously existed permafrost islands has disappeared and second one has reduced by 76% in area during the past ~40 years. In addition, the ground temperature in the Xidatan region has increased from 2012 to 2016, with a mean warming rate of ~0.004°C a−1 and ~0.003°C a−1 at the depths of 6 and 15 m, respectively. The rising of permafrost limit in the Xidatan region is mainly due to global warming. However, some non-climatic factors such as hydrologic processes and anthropic disturbances have also induced permafrost degradation. If the air temperature continues to increase, the northern permafrost boundary in the Qinghai-Tibet Plateau may continue rising in the future. [ABSTRACT FROM AUTHOR]

Being the world’s two largest greenhouse gas polluters and economies, both the United States and China must be involved to achieve meaningful global action to address climate change. To better understand public support for climate change mitigation policy in these countries, this study employs a double-bounded dichotomous choice contingent valuation survey to estimate American and Chinese citizens’ willingness-to-pay (WTP) for climate change action. The results show that on average, US college students and adults have similar WTP values. Chinese adults’ WTP is about three-fifths of US adults’ WTP measured in US dollars, while Chinese students’ WTP is only three-fourths of US students’ WTP. Adjusting for the significant difference in per capita income, Chinese adult and student WTP is over two times larger than that of their US counterparts. In addition, political ideology for US respondents is found to have a significant influence on WTP even when controlling for other covariates, such as environmental concern and climate change belief. [ABSTRACT FROM AUTHOR]

In this study, likely changes in extreme temperatures (including 16 indices) over China in response to global warming throughout the twenty-first century are investigated through the PRECIS regional climate modeling system. The PRECIS experiment is conducted at a spatial resolution of 25 km and is driven by a perturbed-physics ensemble to reflect spatial variations and model uncertainties. Simulations of present climate (1961–1990) are compared with observations to validate the model performance in reproducing historical climate over China. Results indicate that the PRECIS demonstrates reasonable skills in reproducing the spatial patterns of observed extreme temperatures over the most regions of China, especially in the east. Nevertheless, the PRECIS shows a relatively poor performance in simulating the spatial patterns of extreme temperatures in the western mountainous regions, where its driving GCM exhibits more uncertainties due to lack of insufficient observations and results in more errors in climate downscaling. Future spatio-temporal changes of extreme temperature indices are then analyzed for three successive periods (i.e., 2020s, 2050s and 2080s). The projected changes in extreme temperatures by PRECIS are well consistent with the results of the major global climate models in both spatial and temporal patterns. Furthermore, the PRECIS demonstrates a distinct superiority in providing more detailed spatial information of extreme indices. In general, all extreme indices show similar changes in spatial pattern: large changes are projected in the north while small changes are projected in the south. In contrast, the temporal patterns for all indices vary differently over future periods: the warm indices, such as SU, TR, WSDI, TX90p, TN90p and GSL are likely to increase, while the cold indices, such as ID, FD, CSDI, TX10p and TN10p, are likely to decrease with time in response to global warming. Nevertheless, the magnitudes of changes in all indices tend to decrease gradually with time, indicating the projected warming will begin to slow down in the late of this century. In addition, the projected range of changes for all indices would become larger with time, suggesting more uncertainties would be involved in long-term climate projections. [ABSTRACT FROM AUTHOR]

This study quantitatively investigates the long-term dynamics of the association between natural disasters and the migration of agriculturists in historical China. Population pressure is also studied because migration is a population density-dependent phenomenon. This study has adopted correlation analysis, multivariate linear/Poisson regression analyses, and Granger causality analysis to verify the linkages of natural disaster-migration and population-migration in historical China by collecting updated datasets. This study is the first attempt to reveal that the duration effects of natural disasters on the migration of agriculturalists are short-term and almost instantaneous. Although the agrarian society has a low buffering capacity, the effects of natural disasters within a short-term scale could be relieved to some extent. However, population pressure can push migration on a long-term scale despite its limited forcefulness. [ABSTRACT FROM AUTHOR]

This study examines the sampling error uncertainties in the monthly surface air temperature (SAT) change in China over recent decades, focusing on the uncertainties of gridded data, national averages, and linear trends. Results indicate that large sampling error variances appear at the station-sparse area of northern and western China with the maximum value exceeding 2.0 K while small sampling error variances are found at the station-dense area of southern and eastern China with most grid values being less than 0.05 K. In general, the negative temperature existed in each month prior to the 1980s, and a warming in temperature began thereafter, which accelerated in the early and mid-1990s. The increasing trend in the SAT series was observed for each month of the year with the largest temperature increase and highest uncertainty of 0.51 ± 0.29 K (10 year) occurring in February and the weakest trend and smallest uncertainty of 0.13 ± 0.07 K (10 year) in August. The sampling error uncertainties in the national average annual mean SAT series are not sufficiently large to alter the conclusion of the persistent warming in China. In addition, the sampling error uncertainties in the SAT series show a clear variation compared with other uncertainty estimation methods, which is a plausible reason for the inconsistent variations between our estimate and other studies during this period. [ABSTRACT FROM AUTHOR]

We developed a new reconstruction of annual precipitation (August-July) for the Helan Mountains near the southern edge of the Gobi Desert, using a regional tree-ring width chronology. The reconstruction explained 52.1 % of the observed precipitation variance during the period 1953-2008. In addition to the new precipitation reconstruction for the Helan Mountains, two previously published annual precipitation reconstructions from the same region were also used to infer the large-scale precipitation signal of the southern edge of the Gobi Desert. Spatial correlation analyses with gridded precipitation data showed that the tree-ring records were indeed able to capture much of the regional interannual precipitation variability. Using principal component analyses on the precipitation reconstructions and documentary records, 29 large-scale dry events were found during the period AD 1760-2006. Many of these dry events have had profound impacts on the people of the study area over the past several centuries. A notably good agreement with a temperature reconstruction for Zhangye suggests that the precipitation of the Gobi Desert has the characteristics of monsoon rainfall variability (wet-warm and cold-dry). Our precipitation reconstruction exhibited a downward trend during the last two decades, a trend also found in northern and eastern China. It might be caused by a weakening of the Asian summer monsoon induced by global warming (especially increased sea surface temperature). [ABSTRACT FROM AUTHOR]

Based on daily rainfall data collected at 395 gauge stations over eastern China during 1979-2009, the variation in light rain days with intensities of 0.1-10 mm day in the summer half of the year was analyzed. Results indicate that both the light rain amount and the number of light rain days decline distinctly, with trends of −4.89 mm (10 year) and −2.48 days (10 year), respectively. The first two principal components of EOF analysis on light rain days not only show a long-term decrease, but also depict regional differences; specifically, light rain days decline more distinctly in northeastern and southern regions of eastern China. Spatial and temporal features, as well as the periods derived from the EOF analysis of temperature, precipitable water content, and relative humidity in the lower troposphere, coincide with those of light rain days. Composite analysis also suggests that there are fewer light rain days in years with lower relative humidity and precipitable water content in the lower troposphere, while there are fewer light rain days in years with higher tropospheric temperatures. According to the Clausius-Clapeyron equation and the relative humidity equations, relative humidity over eastern China during the period studied decreases by 5.5 % due to lower-tropospheric warming, and decreases by 0.16 % because of the decrease in specific humidity in the same period. Both warming and water vapor content are the reasons for light rain reduction, and warming is deemed the primary cause. [ABSTRACT FROM AUTHOR]