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A primary goal of studying climate change adaptation is to identify the adaptation options that are used to improve crop productivity or reduce the negative impacts of climate change. Many of the adjustments in farm management that farmers adopt do not necessarily represent true adaptations to climate change, an issue often ignored in existing literature and resulting in a risk that policy makers are misled to think that adaptation is easier than it actually is, and thereby underestimate the challenge that climate change presents. The overall goal of this study is to identify whether farmers’ adoptions are enhancing food production and adapting to climate change. The identification uses a plot-level panel from a survey of 619 rural households in three provinces in China and county-level weather data. With the use of plot and county-by-year fixed effects as well as instrumental variable approaches, our estimates show that the autonomous adoptions are not effective in improving crop yields. This implies that farmers’ adoptions cannot be always considered adaptations to climate change. The paper provides a possible explanation for the results and concludes with policy implications. [ABSTRACT FROM AUTHOR]

Greenhouse gas emissions in China and India have been increasing rapidly over the last decade. Scenario studies can provide insight into expected future trends and the emission reduction potential in these regions. The scenarios show that growing population, gross domestic product, and energy demand are likely to lead to a further increase in emissions. At the same time, a decreasing emission intensity would still allow to create decarbonization scenarios in line with the requirements for reaching a maximal warming of 2 °C. There is, however, a wide range of assumptions across these studies. Based on the literature review, this paper observes that key assumptions in scenarios developed by national institutes in China and India differ from those presented by international studies or modeling teams. We explore how this-and other factors like data availability-may influence the interpretation of the scenarios and how international and national modeling groups could learn from each other. Our main recommendation is for more extensive collaboration between national and international research groups, so that national and international scenario studies can be compared in more detail in order to support international negotiations. [ABSTRACT FROM AUTHOR]

Lakes under natural conditions are potential indicators of climate change, but limited evidence has been proposed to explicitly explain the mechanisms of large-scale lake changes associated with climate. In this paper, satellite imageries from the 1970s to 2010 were compared to track the dynamic change patterns of plateau lakes. It aims to identify the forcing of climate change on the lakes in plateau regions of China. Results revealed that: (1) widespread expanding trends in the area and abundance of lakes on wetter plateau regions, by increasing precipitation and snow presented a positive effect on lake levels, as well as warming resulted glacier melting and permafrost degrading contributed to expansion of lakes in the regions covered by glaciers on the Tibetan Plateau by 58-62 % and of 13-20 % on the western Inner Mongolia and Xinjiang Plateau; (2) shrinkage lakes in the main portion of the arid regions were mainly caused by the decreasing wind speed resulted water balance change, irrigation and other human utilization of water resources. Although precipitation decreased, wind speed also has the most dominant impact on decreasing evaporation, followed by solar radiation, both of which offset the effect of increasing temperature, especially in eastern Inner Mongolia and Xinjiang Plateau; (3) thawing permafrost led to shrinkage of lakes in an area of seasonal permafrost, the shrinking and splitting of lakes in a discontinuous permafrost zone, and the rising of lake levels in an area of continuous permafrost; (4) the future of the plateau lakes under climate change must be in question, because the glacier and snow melting water is not sustainable for wetter regions, and the increasing water consumption caused by the farmland expansion for arid regions. [ABSTRACT FROM AUTHOR]

This paper estimates the impact of land use change on soil organic carbon (SOC) sequestration in China from 1985 to 2005 using a nationwide, georeferenced database on land use, soil, and climate. The method presented here is capable of incorporating site-specific information on soil, climate, and land use change into a national-level analysis. We find that grassland restoration contributed to the largest increase in SOC in China from 1985 to 2005, while grassland degradation caused the largest decrease. Overall, land use change resulted in only a small net increase in SOC, by 7.5 TgC (0.02 %), which is statistically insignificant at the 95 % confidence level. A cost-effectiveness analysis indicates that it is important to consider SOC when assessing land conservation programs. Restoring degraded grassland is more cost-effective than returning dry farmland to grassland. Inner Mongolia is a key region for dense grassland restoration. [ABSTRACT FROM AUTHOR]

Land-use change is becoming an important anthropogenic force in the global climate system through alteration of the Earth's biogeophysical and biogeochemical processes. Cropland, which provides people with food, is the most variable vegetation land-use type and is affected by natural and anthropic forces and in turn affects the environment and climate system. This paper investigates the temporal-spatial pattern of cropland transition in the arid and semiarid region of northwest China, using remote sensing data for the late 1980s, 1995, 2000, 2005, 2008, and 2010. The aim was to clarify the change intensity and conversion pattern of cropland with a view to identifying the effects of a series of governmental policies and their influence on the climate system. Mathematical methodologies including the use of a transition matrix model, dynamic degree model, area-weighted centroid model, and area percentage were employed to analyze the temporal change in cropland. Meanwhile, a gridded zonal model with 10-km resolution was used to detect the spatial pattern of cropland transition. During the period from the late 1980s to 2010, cropland increased dramatically by 23,182.17 km, an increase of 13.61 % relative to the area under cultivation in the late 1980s. Cropland transition accumulated in the western oasis-desert ecotone of the study area while it declined in the eastern farming-pastoral ecotone, leading to the westward movement of the cropland centroid. A net decrease in natural vegetation and unused land along with a net increase in built-up land due to cropland conversion was observed in the monitoring period. The three major driving forces of the cropland transition were population growth, economic development, and land-use management governed by the Grain for Green Program. The climate response to different conversion patterns was simply analyzed. However, quantitative assessment of the effect should be undertaken by employing ecosystem and climate models. [ABSTRACT FROM AUTHOR]

Big cities are often said to have big water problems, and Shanghai is no exception. In this paper, we examine and compare the influence of the major factors that give rise to the risk of water insecurity in Shanghai. There is an extensive and diverse literature on these issues, dealt with in isolation, and here, we provide a synthesis of the literature, together with our own assessments and calculations, to assess what are the risks to Shanghai's water supply and what is our degree of confidence in this assessment. We describe the systems that supply water to the city, and past and future changes in the systems, including changes in the glaciers that supply some water to the river, changes in climate, changes in land use, the construction of dams, and water diversions. We show how, at the same time as Shanghai is increasing its dependence on the Yangtze river, water diversions and sea level rise are increasing the risk that this water will be too saline to consume at certain times of the year. This analysis suggests that most of the major drivers of the risk to water security in Shanghai are within the power of environmental managers to control. [ABSTRACT FROM AUTHOR]

Southwest China's Yunnan province has been affected throughout history by climate-induced water stresses, with the 2009 drought as a recent example. To deal with such stresses, mountain farmers have developed many local coping strategies. This paper provides case studies of these coping mechanisms in three mountain communities in Baoshan Municipality, Yunnan province. To minimize water-related environmental and economic vulnerabilities, our results show that upland farmers employ strategies both individually and collectively, which vary according to agroecological zone, economics, and historical period. Climate change is also emerging as an ongoing environmental challenge. We explore China's options for introducing and implementing adaptation policies that link with farmer strategies to respond more effectively to water stresses induced by climate change and other forces. [ABSTRACT FROM AUTHOR]

As a direct result of climate change and extreme weather events, refugee migration has attracted worldwide concern. In this study, we select the North China Plain (NCP) as the case area, where the capital (Beijing) is located during the late Qing dynasty (1790-1911). Based on records of porridge charity, public order (inside Beijing), and revolt events (outside Beijing) in ancient official documents, the interaction between behavior of refugees and the governmental management after floods and droughts is analyzed. The main conclusions can be summarized as follows. (1) Flood/drought has become an important triggering factor of refugee migration during 1790-1911 besides the social factors (e.g., man-land contradiction, fiscal crisis). (2) A negative interaction has existed between the government and refugees throughout the late nineteenth century, which leads to social disorder in the mid-1890s in Beijing and large-scale revolt (the Boxers Movement) in 1900 in the NCP. (3) The negative interaction has been finally ended by the adjustment of migration policy at the beginning of the twentieth century, which officially permits the refugees from the NCP to emigrate to Manchuria and Mongolia outside the Great Wall. The historical case study may provide valuable lessons for the successful adaptation of human societies to future similar occurrences, and will enhance our understanding of the interactions between climate change and social vulnerability. [ABSTRACT FROM AUTHOR]

China's large population and deteriorating environment have created great concern related to the sustainability of food production, especially since details related to this topic remain poorly studied. Thus, an integrated analysis of both crop yield and cultivated area is essential for gaining a better understanding of cereal grain production in China and for making corresponding policies designed to achieve food security. In this study, we adopt trend analysis of both provincial yield and cultivated area to assess the subsequent provincial-level cereal production sustainability between 1980 and 2011 with the goal of providing a better understanding of regional agricultural development. The results indicate that while maize shows the most promise for yield improvement, rice and wheat production is experiencing substantial yield stagnation among most provinces across mainland China. In addition, the trends in spatial patterns are prominently different from those of yields. The sizes of the main rice- and wheat-growing areas in China have declined greatly, suggesting that the related production of these cereals should attract more attention from land management planners and farmers. Specifically, the south-eastern coastal provinces have largely failed to sustain both crop yield and area, while the north-eastern provinces have witnessed thriving agricultural production during the last three decades. Moreover, we find that cereal production in China is significantly affected by governmental policies related to the agricultural sector. Thus, this analysis of food production in China will help policymakers to better understand how the potential implications of food security in China may be applicable to countries worldwide. [ABSTRACT FROM AUTHOR]

Understanding the socioeconomic effects of past climate change is valuable for sustainable social development. However, quantitative analyses of the long-term relationships between climate change and human society have been limited by a lack of long-term high-resolution data that indicate socioeconomic processes. Here, based on 1,091 records extracted from 25 books on Chinese history and economic history written by leading contemporary scholars, an economic proxy series for China with decadal resolution is presented that encompasses the period from BC 220 to AD 1910. A method for semantic differential and integrating descriptions with multi-time resolution is developed. The statistical results show that warm and wet periods were associated with above-average economic performance, while cold and dry climatic scenarios greatly increased the possibility of economic crisis. Temperature was more influential than precipitation in explaining the long-term economic fluctuations, whereas precipitation displayed more significant effects on the short-term macro-economic cycle. It is proposed that the climatic effects on agrarian economic development were highly dependent on the social vulnerability, which is determined by particular social, economic and political backgrounds. From a deep time perspective, our study may provide new insight into the current intense arguments regarding the economic effects of global warming. [ABSTRACT FROM AUTHOR]

China's water source includes the headwaters of the Yangtze, Yellow, and Lantsang (the Mekong outside China) rivers and is located in the heart of the Tibet Plateau, which has an average altitude of 4,200 m. Due to the importance of the Water Tower to the ecological security and economic development of China and South Asia, desertification issues in this region have attracted the attention of the public, scholars, government officials, and international organizations. Combined satellite-derived vegetation indices, field surveys, and surface meteorological data to evaluate the effects of climate change, our analyzed results show that during the early part of the twenty-first century, no desertification occurred in these source areas. However, between 2000 and 2010, human activities may have had a negative effect on about 50 % of the region, although vegetation rehabilitation still occurred during this period. Although the Ecological Protection and Restoration Program was launched in China in 2005, the negative impacts of human activities such as agriculture have still increased in the water source. Vegetation rehabilitation in these source areas appears to be driven mainly by the effect of climate change, and it is possible that human activities do not play an important role in regional ecological and environmental evolution. Although at present we cannot determine whether it was rising temperatures or increasing precipitation that enhanced vegetation growth in the region, our results show that the dominant factors controlling vegetation rehabilitation in China's Water Tower are related to climate. [ABSTRACT FROM AUTHOR]

Potential twenty-first century changes in vegetation distribution and net primary production in China were assessed using three different vegetation models, including new process-oriented but observationally based models for net primary production and vegetation distribution. Climate change projections were derived from a set of seven global climate model outputs, pattern scaled to yield a 2 °C global warming by mid-century. The effects of the climate changes were assessed for the last three decades of the century, by which time global warming has reached 4 °C, with atmospheric carbon dioxide concentration ([CO]) prescribed at 750 ppm. This scenario results in a limited northward expansion of tropical forests along China's southern coast, and a larger northward shift of subtropical forest into the current temperate forest and crop areas. Alpine vegetation on the Tibetan Plateau is largely replaced by boreal and subalpine forest or shrubland. The largest uncertainties (differences between climate and/or vegetation models) occur in northeastern China. However, all models agree on shrinkage of boreal forests in the northeast and the effects of [CO] in promoting woody vegetation at the expense of grasslands. The current cropping systems in North China extend further northward and westward. The productivity of forests in South China increases in all models, although the magnitude of the [CO] effect remains uncertain. [ABSTRACT FROM AUTHOR]

We assessed the vulnerability of 208 endemic or endangered species in China to the effects of climate change, as a part of the project 'Research on China's National Biodiversity and Climate Change Strategy and Action Plans'. Based on the China Species Information System, we selected comprehensive species as analysis targets, covering taxa including mammals, birds, reptiles, amphibians and plants. We applied nine species distribution models in BIOMOD (a package of R software) to estimate the current (1991-2010) ranges and predicted future (2081-2100) ranges of these species, using six climate variables based on Regional Climate Model version 3 (RegCM3) and A1B emission scenario. The model results showed that different taxa might show diverse potential range shifts over time. The range sizes of half of the species (104 species) would decrease, and those of another half would increase. We predicted that the future remaining ranges (intersection of current and future ranges/current ranges) of 135 species would be less than 50 % of their current range sizes. Species that are both endemic and critically endangered would lose more of their range than others. In summary, the most vulnerable species are currently found on the Qinghai-Tibetan Plateau, in the Hengduan Mountain Range, and southern China. Future action plans dealing with climate change in China should be prepared with consideration for vulnerable species and their habitats. [ABSTRACT FROM AUTHOR]

Tongwan City is one of the most famous and best-researched archaeological sites in China. By using palaeoclimatology proxy records from China over the last 2,000 years and archaeological/historical documents, we analyse the possible effect of climate on the collapse of Tongwan City, an ancient urban city of the Daxia state (AD 407-427). During Tongwan City's existence (AD 413-994), two severe cold and drought stages were recorded by both natural proxy data and the synthesis compiled from the historical documents. The first cold and drought stage occurred at about AD 420-550, with the lowest point centred at about AD 500. The second cold and drought stage occurred at about AD 780-950. These periods correspond to the times of climate deterioration, especially weak summer monsoons, which eventually resulted in the intensive desertification and collapse of Tongwan City. [ABSTRACT FROM AUTHOR]

This research presents an evaluation of glacier recession and glacial-lake expansion in the Rongxer basin in the Mount Qomolangma National Reserve of central Himalaya. Changes in glacier and glacial-lake surface areas in the Reserve between 1975, 1992 and 2005 have been estimated using remote sensing and GIS techniques that have integrated field data from 2009, 1:50,000 scale topographic maps, ASTER satellite data from 2009, and Landsat MSS/TM images in 1975, 1992 and 2005. By 2005, the glacier surface area had declined from 596.52 to 451.58 km with a total area loss of 144.94 km, and glacial lakes had increased from 3.55 to 7.87 km, an increase of 121.69 %. The volume of glaciers was reduced by 69.99 km from 1975 to 2005. The observed changes in the extent of glaciers are in line with the observed atmospheric warming in the Rongxer basin. Records from the Tingri station and Nyalam station have revealed warming during the ablation season since the 1970s at a rate of 0.03-0.04 °C a in the northern and central Rongxer basin. At higher elevations in the study area, represented by the Tingri and Nyalam meteorological stations, the summer warming was accompanied by negative anomalies in annual precipitation since the 1970s, likely enhancing glacier retreat and glacial lake expansion. [ABSTRACT FROM AUTHOR]

China is a key vulnerable region of climate change in the world. Climate warming and general increase in precipitation with strong temporal and spatial variations have happened in China during the past century. Such changes in climate associated with the human disturbances have influenced natural ecosystems of China, leading to the advanced plant phenology in spring, lengthened growing season of vegetation, modified composition and geographical pattern of vegetation, especially in ecotone and tree-lines, and the increases in vegetation cover, vegetation activity and net primary productivity. Increases in temperature, changes in precipitation regime and CO concentration enrichment will happen in the future in China according to climate model simulations. The projected climate scenarios (associated with land use changes again) will significantly influence Chinese ecosystems, resulting in a northward shift of all forests, disappearance of boreal forest from northeastern China, new tropical forests and woodlands move into the tropics, an eastward shift of grasslands (expansion) and deserts (shrinkage), a reduction in alpine vegetation and an increase in net primary productivity of most vegetation types. Ecosystems in northern and western parts of China are more vulnerable to climate changes than those in eastern China, while ecosystems in the east are more vulnerable to land use changes other than climate changes. Such assessment could be helpful to address the ultimate objective of the United Nations Framework Convention on Climate Change (UNFCCC Article 2). [ABSTRACT FROM AUTHOR]

We review published stratigraphic, archaeological and pedosedimentary evidence in order to reconstruct the history of soil erosion in China. Documentary evidence of climatic and flood events of the Yellow River and modern hydrological and meteorological data are synthesised to analyse the history of past human activity and its effects on soil erosion intensity during four nested periods of time during the Quaternary. The most intensive period of erosion during the Quaternary was in the Holocene. During the Holocene, intervals of intensive soil erosion occurred at 7500–7000 BP, 200 BCE–0 CE, 1000–1600 CE (Christian era) and during the 1930s, 1950s and the later part of the 1960s of the last century. Large-scale human activity including warfare during early Chinese history, population migration, the inner wars in 1930s, the Cultural Revolution and the recent national campaign to aid soil and water conservation are all closely related to the rate of soil erosion on the Loess Plateau and to sediment loads in the Yellow River. Overall, soil erosion during the transition from dry-cool to wet-warm climates was more intense than during wet-warm and cool-dry climatic episodes, but serious accelerated soil erosion has occurred during the last 2,500 years because of man-induced devastation of vegetation and other anthropogenic disturbance of the environment. Modern rates of soil erosion on the Loess Plateau are a combination of both intensive natural and human-induced erosions and are some four times greater than occurred in the geological past. The recent implementation of soil and water conservation measures has decreased sediment load in the Yellow River by 25%. [ABSTRACT FROM AUTHOR]