Using the daily precipitation data from 753 stations in China during 1961-2010 and reanalysis data, the changes of summer precipitation, including the changes of the summer rainfall total, the rainfall amount of extreme precipitation, and the frequency of extreme precipitation, were investigated. These changes are similar in spatial patterns, with increasing changes over the south, and decreasing changes over the north. The Poisson regression was used to investigate the change of the frequency of extreme precipitation. The frequency increased over the Yangtze River basin and South China, and decreased over the region to the north of the Huaihe River basin. It is found with a new diagnosis tool that at most stations, the change of the the summer rainfall total is dominated by the change of intensity, and the change of the rainfall amount of extreme precipitation is dominated by the change of frequency. The relative importance of the changes in moisture and air temperature in the variability of summer rainfall total was also analyzed. In most areas north to the Yellow River, the variability of the summer rainfall total is dominated by the moisture change, while over the Yangtze River basin and South China, it is dominated by the air temperature change.

Tree-ring width standardized chronology (STD) was created by Sabina przewalskii Kom which collected in Xueshan Township of Qinghai Province. Analyzing the correlation between STD and climate factors of 4 meteorological stations in the source region of Yellow River. The results showed that STD was significantly correlated with maximum air temperature of the whole area in May-June and the correlation coefficient was -0.65. According to the results above, the maximum air temperature anomalies sequence in May-June of Yellow River source region during 1618-2009 was reconstructed. The reconstructed function embodied a certain degree of reliability and stability after level-one-out test and the explain variance reached 42.2%. There were 8 warm periods and 8 cold periods in the reconstructed maximum air temperature sequence over the past 400 years. Warm periods included 1644-1656, 1727-1746, 1786-1797, 1817-1835, 1860-1885, 1916-1934, 1952-1968 and 1992-2005, while cold periods contained 1632-1643, 1657-1696, 1747-1764, 1798-1816, 1836-1859, 1898-1915, 1935-1951 and 1969-1991. Comparing the reconstructed sequence in this study with temperature series reconstructed in Zadoi, on northeastern Tibetan Plateau and in the source region of Yangtze River, their trends were basically the same in common years. In addition, the reliability of this reconstructed sequence could be confirmed by some documents and historical records.

Climate classification of China in the end of the 20th century was simulated by using 21 CMIP5 models data and Climatic Research Unit (CRU) data sets. Then, climate classification in the mid and end of the 21st century under the RCP2.6 and RCP8.5 scenarios was also simulated. The results show that the temporal distribution pattern of temperature and precipitation can be simulated well by CMIP5 data in China and the climate classification simulated by using CRU data sets has good fitness with that of FAO. There is no significant change in climate classification in the 21st century relative to that in the end of the 20th century. The range of Cwa and BS climates will increase by 28.2% /86.9% and 24.1% /49.4% in the mid /end of the 21st century under RCP8.5, compared with that in the end of the 20th century. Dwa climates will expand, but ET and BW climates will decrease significantly in the end of the 21st century.

A survey of research progress on assessment methods for climate change and human activity affecting hydrological factors in separated manner was executed in this study. A novel idea of source attribution was proposed that changes in hydrological processes brought by environmental reasons could be attributed into three sources: climate natural variability, human-induced climate change, and human activity. Thus a framework was presented. Due to the complex uncertainties in the hydrological processes under environmental change, uncertainty factors in hydrological processes were deeply explored, thus common quantitative and qualitative uncertainty evaluation approaches were summarized. Moreover, the Info-Gap theory was addressed to solve the problem of qualitative uncertainty (Knightian uncertainty) estimation. Finally, to enhance the ability of mitigation and adaptation for environmental change, it demonstrates that in future studies on environmental change impacts should be strengthened in terms of climate natural process, human-induced climate change and human activity. Uncertainty analysis should be an original part of environmental modeling rather than additional or dispensable component. In the impact assessing, it suggests that uncertainty estimation should be fully stressed. Further uncertainty information based on catchment-scale risk management should be facilitated in catchment-scale management decision-making.

Based on China’s water resources assessment and water resources bulletins, time series of precipitation, water resource, and water demand projection in base year were established, and the impacts of precipitation changes on water supply and demand in Haihe River region were analyzed by comparison in two phases namely 1956-1979 and 1980-2010. The results showed that the decrease of precipitation significantly reduces water resources 8.6 billion m³ and increases the amount of water demand 2.2 billion m³ annually during 1980-2010. Socioeconomic water scarcity caused by precipitation change is 7.7 billion m³, occupying 75% of the total water scarcity. The precipitation decreasing aggregates the conflicts between water demand and supply.

Based on the data of daily mean temperature, maximum and minimum temperature, duration of sunshine, from 101 meteorological stations in Xinjiang in 1961-2013, the fundamental spatial-temporal change characteristic of key climatic factors (≥15℃ days, ≥20℃ temperature-light index and mean range of daily temperature from June to August) affecting melon-planting were analyzed by using the methods of linear regression, accumulative anomaly, guarantee rate analysis and mixed spatial interpolation technology based on ArcGIS. And the impacts of climate change on melon-planting zoning were studied by combining with the change characteristics of key climate factors before and after mutation. The main results showed, spatial distribution of ≥15℃ days, ≥20℃ temperature-light index, and mean range of daily temperature from June to August had very obvious difference from place to place in Xinjiang. Generally, they were more or higher in south and east than in north and west, in plain and basin than in mountain regions. In the background of global warming, the ≥15℃ days, ≥20℃ temperature-light index presented significantly increasing trend with the rate of 2.493 d/10a and 0.06/10a, respectively, and they had mutation in 1997. But mean range of daily temperature from June to August had a significantly decreasing trend with the rate of -0.249/10a and had mutation in 1987 in 1961-2013. According to the climatic conditions of various maturing melon growth and quality, melon-planting climatic zoning can be divided into 4 regions and 7 sub-regions in Xinjiang. Due to climate change, the best planting zone expanded significantly in terms of mid-maturing and late-maturing melon, the second-best planting area of them decreased, the suitable planting area of early-maturing melon, unsuitable planting area for melon decreased after 1997 in Xinjiang.

Ten provinces in China were chosen to assess the dynamics and impact of agro-meteorological disasters in 1978-2008 by the application of agricultural statistical data on statistical methods, and the spatial risk distribution of agricultural disasters were analyzed. The results show that drought disaster was one of the most important disasters in China; however, a high temporal variation was observed in the frost disaster areas. In terms of spatial variation, the risk of drought disaster in the eastern provinces was higher than that in the western, the northern provinces higher than the southern; high flood disaster risk mainly occurred in the Yangtze River region and the northeastern region in China; Qinghai Province in Tibetan Plateau had a high risk in hail disaster. There were large differences in the risk probabilities of four agro-meteorological disasters in China. The probabilities of drought and flood disasters were much higher than those of frost and hail disasters.

Greenhouse gases (GHG) data submitted in April 2014 about land use, land use Change and forestry ( LULUCF), energy, industrial processes, solvents and other product use, agriculture, and waste for 35 parties in Annex B under the first commitment period of Kyoto Protocol were collected to estimate their different relative contributions on GHG emission reduction. The results show that proprotion of GHG emission reduction in different fields to total emission reduction were in order from high to low as energy for 62.6%, industrial processes for 13.9%, agriculture for 13.4%, LULUCF for 7.4%, waste for 2.6%, and solvents and other product use for 0.1%; Average proprotion of GHG emission reduction in different sectors to total GHG emission in base year for different parties in Annex B were ordered from high to low as energy for 8.7%, agriculture for 3.0%, LULUCF for 2.5%, industrial processes for 1.3%, waste for 0.5%, and solvents and other product use for 0.1%. As a whole, energy sector dominated GHG reduction, with agriculture and LULUCF sectors having an assistant role; most of the parties could get weak GHG removal from their chosen LULUCF activities. However, the relative contribution of GHG emission reduction from LULUCF was very small, which only accout for 12% of emission reduction in energy. But it’s different for New Zealand and Iceland. Fifty percent of emissions in other five fields can be offset by GHG removal from LULUCF in these two countries.

The Lima Call for Climate Action adopted at the Lima Climate Conference specifies that the principles of the United Nations Framework Convention on Climate Change, including the principle of common but differentiated responsibilities, shall apply to the new climate agreement to be adopted at the Paris Climate Conference in 2015. Decisions on other heavily debated items, including the intended nationally determined contributions, were also made at the Lima Climate Conference. The significant achievements in Lima and the positive momentum have laid a solid foundation for the adoption of a new climate agreement at the Paris Climate Conference. Four measures are proposed for China to meet great challenges in addressing climate change beyond 2020, including early formulation and issuance of a climate change law, establishment of a greenhouse gas emission trading scheme, promotion of advanced climate technology investments, and further international engagement for climate change.

Shanghai energy-environment-economy CGE model was developed to simulate the economic impacts and co-benefits of different carbon emission trading schemes (ETS) under alternative employment conditions. The results illustrate that double dividend from carbon emission trading is available supposing that the labor released out from ETS sectors is absorbed immediately. Otherwise, GDP will decrease 1.5%-2.4% compared to baseline due to the implementation of ETS in 2020. Under the scenario with all sectors covered by ETS, the carbon price is relative lower, which increase from 30 RMB/t CO₂ in 2013 to 202 RMB/t CO₂ in 2020. The negative impact on the competitiveness of energy-intensive sectors is smaller compared to the scenario that part of sectors are covered, however, the negative impact on GDP is the biggest. Carbon emission trading will bring obvious environmental co-benefits, and play an important role on the realization of SO₂ and NO_X mitigation target.