Abstract: The PRECIS, a regional climate model system developed at the UK Met Office Hadley Centre for Climate Prediction and Research, nested in one-way mode within the HadAM3H, a higher-resolution version of the atmospheric component of the Hadley Centre climate model HadCM3, was employed to analyze the future climate change in 2071-2100 under the SRES A2 scenario over China relative to the reference period of 1961-1990. The mean climate state as well as the frequency and intensity of daily extreme events were investigated at various temporal and spatial scales, with a focus on surface air temperature and precipitation. Regarding the interannual variation of projected temperature and precipitation over the whole integration period, we find that the temperature shows a persistently increasing trend, especially in Northwest China and Northeast China. The projected precipitation in the future shows generally greater amounts than in the reference run despite significant interannual variation. Based on the spatial distribution, the winter precipitation would decrease in the south of China while greatly increase around the Yellow River, the changes of precipitation in summer would be vice versa to winter. A substantial increase (decrease) of hot (frost) spells is projected along with increasing of maximum and minimum temperatures. Wet spells tend to be more frequent, accompanying the increase of precipitation amounts.

Based on the multi-decadal climate change simulations from the RegCM3 model with a resolution of 20 km, changes in precipitation events of different intensities in 2071-2100 under the SRES A2 scenario were analyzed. The events were classified to RR1 (1-10 mm/d), RR10 (10-20 mm/d) and RR20 (≥20 mm/d) according to the daily rainfall. Verification of the model performances in simulating present (1961-1990) distribution of the rainy days was firstly carried out. The results show an overestimation of RR1 (light rain days) and a general underestimation of RR20 (heavy rain days) in southern China by the model as compared to the observations. Under the IPCC SRES A2 scenario in the end of the 21st century (2071-2100), the projection shows different changes in the RR1, RR10 and RR20 events over different areas, with a general increase in heavy rain events over most of China. The slight increase in annual mean rainfall in China is basically contributed by the increase in heavy rain events.

Based on the temperature and precipitation observation data from 1951 to 2008 and the projected data from 2010 to 2099 by the multi-model ensemble under the SRES A1B, A2 and B1 scenarios in the 21st century, we analyzed the annual and seasonal changes of precipitation and temperature in the past 58 years, and estimated the climatic tendencies in the next 90 years. The results show that the annual precipitation decreased by 46.4 mm in the past 58 years, which wasn't statistically significant. The precipitation under each scenario has an obvious increasing tendency in the next 90 years. The increasing rates of precipitations under SRES A1B, A2 and B1 are all larger than that in the past 58 years. We also find whether in the past 58 years and in the next 90 years under each scenario, annual mean temperature is increasing and it is statistically significant.

The concentrations of carbonaceous aerosols and soluble ions (Cl-, NO3-, SO42-, Na+, K+, Mg2+, Ca2+) in the 29-meter-long PLZ-4 ice core, retrieved from a maritime glacier on the southeastern Tibetan Plateau, were analyzed by a Thermal/Optical Carbon Analyzer and ion chromatographs, respectively. The results show that elemental carbon (EC), water insoluble organic carbon (WIOC) and soluble ions concentrations in this ice core were increasing dramatically during 1998-2005. Meanwhile, EC concentrations and EC/WIOC ratios showed significant seasonal variations; high concentrations and ratios occurred in non-monsoon seasons and low concentrations and ratios in monsoon seasons, indicating that the carbonaceous aerosols recorded in the southeastern Tibetan glacier were highly related with South Asian brown clouds. Besides, the average EC concentration of >10 ng/g in pre-monsoon, especially from April to May, could provoke the decreased snow/firn albedo and glacier melting, which can not be ignored.

Using the meteorological observation data including temperature and precipitation at 66 stations over the Tibetan Plateau from 1961 to 2007, by means of the typical climate zoning, the spatio-temporal variations of climatic variables over the plateau in the recent 47 years were systematically studied, and the differences of climate change in different sub-regions were shown. The results indicate that the climate over the Tibetan Plateau overally showed a significant warming trend in the recent 47 years, the annual mean temperature rose at a rate of 0.37℃/10a; the warming was more remarkable in nighttime than in daytime, and in winter than in other seasons. The change from colder to warmer was the most significant in February, but the least in August, when climate showed a cooling trend in some areas. Climate warming at the edge of the plateau was more obvious than in the hinterland. The northern of Qinghai, especially the Qaidam Basin was a most sensitive area to climate change. Precipitation showed a rising trend at a tendency rate of 9.1 mm/10a; but regional differences were very apparent, the western of Sichuan, which lies in the southeast of Tibet, was the most significant in precipitation-increasing in the whole Tibetan Plateau; Precipitation in winter and spring (from December to May of the next year) in all areas increased with the climate warming; but the drought trend in the upstream of Yellow River was obvious after 1987.

The warming trend in Beijing was analyzed based on the homogenized land surface air temperature data at Nanjiao weather observatory during 1951-2008. The analysis shows that the mean maximum and minimum temperatures increased asymmetrically at a rate of 0.26℃/10a and 0.46℃/10a, respectively. It is found that among four seasons winter is the longest season and autumn is the shortest season; summer is getting longer at a rate of 4.4 d/10a, and winter is becoming shorter at a rate of 4.7 d/10a; since 1951 the starting dates of spring and summer have become earlier at a linear rate of 3.0 d/10a and 2.5 d/10a, and on the contrary, the starting dates of autumn and winter have gradually become later at a rate of 2.0 d/10a and 1.7 d/10a respectively. The correlation analysis suggests that the starting dates of spring and summer are significantly negatively correlated with the annual mean temperature; while those of autumn and winter are remarkably positively correlated with the annual mean temperature.

Based on the daily minimum and mean temperature data of 192 stations in South China (Guangdong, Guangxi, and Hainan provinces) from 1 January 1961 to 31 December 2008, climatic characteristics and variations of cold wave frequency in South China were first analyzed. An intensity index of cold wave was defined and intensity changes of cold wave activities in South China were analyzed. The results of climatic analysis show that there were 221 times cold wave processes in South China in the last 48 years. The cold waves might occur in the period from October to April of the next year, and 88.7 % of them concentrated in December, January, February and March. It has been found that the mean annual frequency and mean temperature reduction of cold wave processes of single station gradually reduced but the mean minimum temperature gradually increased from north to south and from inland to coast in South China in the past 48 years. The mean maximum temperature reduction of cold wave processes of single station ranged from 11.5 to 16.0℃. In the last 48 years, cold wave activities in South China showed a generally declining trend, but its frequency and intensity still exhibited monthly, yearly and decadal variabilities. The ratios of strong and medium cold waves have gradually decreased since the 1980s, however the ratio of weak cold waves has significantly increased, and the strongest cold wave in the last 48 years occurred in South China in 2008.

Changes of precipitation in the Taiwan area in 1961-2008 was analyzed by using EOF, REOF, M-K abrupt change analysis. The results show that the annual precipitation was great in the Taiwan Island, but far smaller in the Pescadores. The spatial distribution of annual precipitation in the Taiwan Island not only had the coherence in the whole area, but also showed variations from east to west and from south to north. The annual rainfall field in the Taiwan Island can be divided into north, mid-west and southeast sub-regions. The annual precipitation displayed an increasing trend and abrupt changes in the island except the southeast sub-region.

Based on the results of long-term experiments and observation, a case study was conducted in a desert oasis of the Heihe River basin to develop adaptive technologies of oasis agriculture and to evaluate the adaptation potentialities to climate change. It is indicated that technologies, such as ridge furrow irrigation, mixture sowing of crop and concomitant plant, optimizing fertilizer and water application, and promoting the jujube/crop intercropping system , could be applied on a field scale to adapt to climate change and strategies such as readjusting crop structure, extending shelterbelt specification, reducing the frequency of shelterbelt irrigation, and replacing high water consumption trees (Populus simonii) in the oasis defending system with drought-enduring plants, could be adopted at oasis level. The evaluation results suggest that the water saved by adopting these technologies would amount to 2.96 × 108 m3 per year, but without decreasing the oasis agricultural productivity and reducing the oasis stability.

China is the largest country of HCFCs (hydrochlorofluorocarbons) production and consumption, and the production of HCFC-22 (Chlorodifluoromethane) accounts for more than 80% of all HCFCs. In 2007, the international community decided to speed up the elimination of HCFCs, China's implementation will bring great benefits to the global environment. This paper concentrates on the residential air-conditioner industry and analyzes the environmental benefits of accelerating the phase-out of HCFC-22 in China. According to the comparison of the baseline and phase-out scenarios of HCFC-22, it's found that using HC-290 (propane) as a refrigerant alternative will directly reduce the greenhouse effect, and indirectly reduce the emission of greenhouse gas due to the reduction in the electricity consumption. The comparison of two scenarios of HC-290 and HFC-410A refrigerant alternatives shows that the use of HC-290 refrigerant will produce significantly higher environmental benefits than the use of HFC-410A refrigerant.

Bali Action Plan was approved in the COP13 of UNFCCC, and measureable, reportable, verifiable (MRV) nationally appropriate mitigation commitments or actions were proposed to be included in the next international agreement in order to reach an agreed outcome and to adopt a decision at its fifteenth session. However, what is the definition and scope of MRV, and what are the responsibilities for developed countries and developing countries in implementing the MRV actions, respectively, are still not clear. This paper presents the framing issues for national mitigation actions based on the ideas from the authors, and analyzes key points in the MRV framework. The paper also discusses how to implement the MRV of China's national policies and mitigation actions.

In this paper, a comprehensive analysis of the impacts of climate change on business opportunities and challenges is provided. The U.N. Global Compact's "Caring for Climate Change" brings about new opportunities for the enterprises to respond to the global response to climate change. The Global Compact is a good platform for the global enterprises to jointly cope with climate change, to practice corporate social responsibility and to establish good corporate image. In addition, this paper expounds the status quo of Chinese private enterprises to address climate change through research and analysis.