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Given that climate extremes in China might have serious regional and global consequences, an increasing number of studies are examining temperature extremes in China using the Coupled Model Intercomparison Project Phase 5 (CMIP5) models. This paper investigates recent changes in temperature extremes in China using 25 state-of-the-art global climate models participating in CMIP5. Thirteen indices that represent extreme temperature events were chosen and derived by daily maximum and minimum temperatures, including those representing the intensity (absolute indices and threshold indices), duration (duration indices), and frequency (percentile indices) of extreme temperature. The overall performance of each model is summarized by a 'portrait' diagram based on relative root-mean-square error, which is the RMSE relative to the median RMSE of all models, revealing the multi-model ensemble simulation to be better than individual model for most indices. Compared with observations, the models are able to capture the main features of the spatial distribution of extreme temperature during 1986-2005. Overall, the CMIP5 models are able to depict the observed indices well, and the spatial structure of the ensemble result is better for threshold indices than frequency indices. The spread amongst the CMIP5 models in different subregions for intensity indices is small and the median CMIP5 is close to observations; however, for the duration and frequency indices there can be wide disagreement regarding the change between models and observations in some regions. The model ensemble also performs well in reproducing the observational trend of temperature extremes. All absolute indices increase over China during 1961-2005. [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]

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]

Climate change has emerged as one of the most important environmental issues worldwide. As the world's biggest developing country, China is participating in combating climate change by promoting a low carbon economy within the context of global warming. This paper summarizes the pathways of China's low carbon economy including the aspects of energy, industry, low carbon cities, circular economy and low carbon technology, afforestation and carbon sink, the carbon emission trading market and carbon emission reduction targets. There are many achievements in the implementation of low carbon policies. For example, carbon emission intensity has been reduced drastically along with the optimizing of energy and industry structure and a nationwide carbon trading market for electricity industry has been established. However, some problems remain, such as the weakness of public participation, the ineffectiveness of unified policies for certain regions and the absence of long-term planning for low carbon cities development. Therefore, we propose some policy recommendations for the future low carbon economy development in China. Firstly, comprehensive and long-term planning should be involved in all the low carbon economy pathways. Secondly, to coordinate the relationship between central and local governments and narrow the gap between poor and rich regions, different strategies of carbon emission performance assessment should be applied for different regions. Thirdly, enterprises should cooperate with scientific research institutions to explored low carbon technologies. Finally, relevant institutions should be regulated to realize comprehensive low carbon transition through reasonable and feasible low carbon pathways in China. These policy recommendations will provide new perspectives for China's future low carbon economy development and guide practices for combating climate change. [ABSTRACT FROM AUTHOR]