Disastrous floods happened in several river valleys over eastern China in 1755. Subsequently, serious floods occurred in the lower valleys of the Huanghe and Huaihe rivers in 1756 and 1757, a rarely seen precipitation pattern of north-floods-south-droughts appeared in China for the two successive years. Serious meteorological disasters and extreme climatic event happened under a climatic background of a warm phase of the Little Ice Age. In this paper, the rainy and flooding situation and the weather characters of these years are reproduced by means of historical literature records, and the state charts of areas of prolonged rainy, overflow and concomitant famine, insect pest, and pestilence in these years are made. In 1755, the mid to lower basins of the Huanghe, Huaihe and Yangtze rivers experienced a prolonged rainy season with multiple torrential rain events. The continuous rainy period exceeded 40 days in the Huanghuai region. An early Meiyu occurred, and the duration of the Meiyu period in the lower Yangtze River basin was 43 days, which is the longest in the 18th century. In particular in Nanjing the annual rainfall of 1755 was 1378 mm, which is the highest record of the 18th century. The year of 1755 was characterized by lower temperature in summer, early frost in autumn and heavy snowfall and freezing rains in winter, with the rainy season starting earlier, persisting for a longer period, and featuring of high precipitation intensity. The synoptic and climatic aspects of 1755 were extremely similar to those of 1823 and 1954, two typical severest floods years. And all the 3 extreme flooding events coincidently took place in the minimum-value phase of the solar activity period.

An objective identification technique was used to detect regional extreme low temperature event (RELTE) during 1960-2009, and the spatial distribution and temporal variation of the events were investigated. Results indicate that the probability distribution of the minimum temperature and the latitude of the geometrical center of RELTEs both obey the bimodal distribution. The center of RELTEs was mainly located in two latitude belts of nearly 30°N and 42°N. Before the middle 1980s, the south and north belts coexisted but the north belt weakened obviously since then. Besides, the annual accumulative values of the frequency, intensity and maximum covering area of RELTEs decreased overall during 1960-2009 and there was an obvious phase shift at the end of 1980s and the variation became flat after 1990s. These characters might result from the RELTEs with long duration and wide space range which accounted for 10% of all events. Further more, the integration index that reflects the overall influences of RELTEs were further investigated.

Decadal variations of extreme characteristics of tropical cyclones (TC) influencing China were investigated based on the tracks, landfalling information, precipitation and wind data of the TCs in the period 1949-2009. The extreme landfalling date events had less frequency in the 1970s and the 2000s. The extreme maximum wind and minimum pressure events had the highest frequency in the 2000s. The extreme precipitation duration events had the highest frequency in the 1970s, and the extreme strong wind duration events had the maximum frequency in the 1980s. The number of stations whereat the extreme maximum daily precipitation or process precipitation were observed, was the largest in the 1960s, and the number of stations whereat daily maximum wind speed events were observed, was the largest in the 1980s.

Based on the major flood disaster events of China railway during 1951-1998, the frequency, disastrous degrees, spatiotemporal distribution and their dynamic characteristics were analyzed. The results show that on the average over the period of 1951-1998, there were 3.1 major flood disaster events and 63 days of traffic interruption each year in China railway. 1954, 1960, 1981, 1991 and 1996 were the peak times of major flood disaster events of China railway. The flood disasters mainly took place from May to August, and the most of them occurred in July yet the most traffic interruption days were in August. With regard to the regional distribution of major flood disaster events, most of them occurred in Northeast China, Northwest China, East China and South China. The Lanxin line had the most flood events, followed by the Jingguang line and Longhai line, and the Huainan line was the severest disastrous line in China. Causes for major flood disasters of China railway in different areas were also discussed.

Discharge from 1961 to 2099 through the outlet of Xijiang River, the biggest sub-basin of Zhujiang River, was simulated by hydrological model HBV-D using the precipitation and temperature projected from three climate models (GCMs) under three greenhouse gas (GHG) emission scenarios. The following conclusions can be drawn through analyzing the changes of water resources and flood frequency relative to the reference period of 1961-1990. Annual precipitation and annual runoff will increase after 2050. In addition, Area average precipitation and runoff show increasing trends in each month from May to October, but decreasing trends from December to next February based on the results of Mann-Kendall trend analysis. More and larger floods will occur in future. Potential increased runoff during the low flow season before 2030 will ease the pressure of water demand, but the increased runoff in the high flow season, and more frequent and larger floods will bring more pressure on flood controlling after 2050. These impacts of climate change on hydrological processes in the Zhujiang River basin should be considered when planning adaptation and mitigation strategies.

The tendency and persistency of potential evaporation in the recent 30 years were analyzed based on the observational data of monthly average maximum temperature, minimum temperature, precipitation, wind speed, relative humidity, and sunshine duration of 9 stations in the Nujiang River basin in Tibet from 1981 to 2010 by linear trend analysis and Rescaled Range (R/S) analysis, as well as the Penman-Monteith model. And the relationships between potential evaporation and influential elements, such as sunshine duration, mean wind speed, and precipitation, were also discussed. The results show that the seasonal potential evaporation decreased during 1981-2010. Also, a negative trend of annual potential evaporation, i.e., a rate of -18.4 mm?(10a)-1 significant at the 95% confidence level, was detected. The results of R/S analysis show that the summer, autumn, winter, and annual series of potential evaporation were persistent and it will assume continuous decrease in future, especially in winter. From the 1980s to the 2000s, the decadal anomaly of potential evaporation was positive in the 1980s, whereas negative in the 1990s and the 2000s. It is thus obvious that the decrease of potential evaporation was mainly caused by the significant decrease of wind speed in all seasons, however in spring it was also correlated with significant increase in precipitation, and in summer it might also be related to decrease in daily temperature range.

Based on the meteorological data collected at nine typical stations in the forestry region of southeast Tibet, the climate change in the region was analyzed. The results show that the annual mean temperature in southeast Tibet forestry region increased about 0.9℃ from 1954 to 2009, in particular the increment of mean temperature in winter was 1.47℃. According to the Mann-Kendall test, the abrupt change of annual mean temperature occurred in 2001. Meanwhile, the annual precipitation in the forestry region has distinctively increased 185 mm during 1954-2009, most of the increment happened in spring (83 mm) and autumn (55 mm), and the abrupt change of annual precipitation occurred in 1979. The climate change in the forestry region was more significant compared with those in Northeast China, North China and Northwest China, and it became more significant along with the increasing altitude of station.

From the perspective of life cycle assessment (LCA), the development, construction, operation of all kinds of new energy power generation technology do bring some greenhouse gas (GHG) emissions. This sparks "low carbon" property concerns of new energy power generation technology. Based on domestic and foreign relevant literature, this paper compares and estimates the GHG emission coefficients of traditional power generation and new energy power generation in China with the LCA, and then calculates the GHG mitigation potential of new energy power generation alternative to traditional coal-fired power generation, according to the national development planning objectives of new alternative energy generating. The results show that the GHG emission coefficients of new energy power generations are much lower than that of traditional coal-fired power generation even with LCA accounting, and the GHG mitigation potential of new energy substitution is still large.

Under the current unclear situation of global carbon market and the start-up of the voluntary emission reduction market, and facing the opportunities of setting up domestic energy-saving and emission reduction targets and the implementation of eco-compensation mechanism, this paper introduces the international carbon market situation, and concludes the potential project types of agricultural greenhouse gas (GHG) reduction and trading. And then discusses how China could actively explore the utilization of market base instrument in the agricultural GHG reduction while getting over the difficulties like small amount of unit reduction, high transaction cost, lack of methodologies and third party verifier, as well as the challenge of no unified standard of domestic trading platform.

The intensity allocation criteria of carbon emission permits and its influence on China誷 regional development were analyzed through the 30-province/autonomous region CGE model. Simulation results show that: industrial intensity criteria without taking regional economic development into account, deepens the unbalanced development of regional economy; regional intensity criteria without taking industrial attributes into account, exerts little negative impact on regional harmonious development, but relatively high negative influence on high-carbon-emission industries. The two-step allocation scheme that the central government allocates emission permits to provincial governments based on regional economic development and then provincial governments allocate emission permits to emission resources or entities based on industrial attributes, is a feasible and operable choice.

Carbon capture and storage technologies are more and more concerned by the international community, and many countries promote the carbon capture and storage technology by legislation. Among them, the onshore carbon capture and storage technology is more noticeable. It involves four processes of capture, transport, injection and storage of carbon dioxide. The capture and transport processes can be regulated by the existing national laws, while the injection and storage processes require new laws to be regulated. According to legislative experience of foreign onshore carbon capture and storage technology, viewing from the current relevant laws and regulations, China should build the public law system focusing on regulation and the private law system focusing on remedy in order to promote the healthy development of onshore carbon capture and storage technology.