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对流层作为地球空间环境中与人类活动最为密切的大气圈层之一,与人类的生产和生活密切相关。水汽是对流层中最重要的组成部分之一,尽管所占比例较小,但在多种气候和一系列天气现象中都扮演着关键角色。利用现代技术手段,掌握对流层中水汽的时空变化,对大气结构的垂直稳定度、暴风雨以及强对流等灾害性天气的形成和演变都具有重要影响。近年来,随着全球气候变暖,各种灾害性天气频发,针对大气水汽的研究也备受关注。

综述了在全球气候变暖背景下，东北地区农业气候资源、农业气象灾害的变化特征以及主要农作物对气候变化的响应。结果表明，气候变暖给东北地区农业带来的影响利弊共存，主要表现为东北地区主要农作物生长季节温度升高、热量资源增加，适宜农作物生长的时期延长、适种区域扩大，为作物的光温生产潜力以及产量的提高提供了潜在的可能。但由于光照及水资源的限制以及CO2浓度的增加而引发的温室效应，对农作物的产量和品质也产生了负面影响。极端天气事件增加，农作物生态环境恶化，干旱、洪涝、盐碱化速度加快，尤其是近几年受全球变暖的影响，东北地区主要农作物受干旱灾害的影响最为明显。降水总量减少和降水分布不均匀，使东北地区成为受气候变化影响最敏感和脆弱地区之一。

P467; 利用1961-2010年青海高原34个气象台站逐日平均气温资料，研究了气候变暖对青海采暖期能耗的影响及预测模型，并根据未来气候情景，对未来青海高原采暖能耗进行了预估．结果表明：青海高原自1998年开始呈显著增暖趋势，气候变暖后全省平均采暖期缩短9 d，各地采暖度日数普遍减少，尤以青海高原西南部减幅最大，采暖强度明显减弱．理论上由气候变暖导致的青海高原地区采暖耗能降低4?9％～15?3％，全省平均单位面积可节约标煤量1?79 kg/m2．未来温室气体中等排放（ SRESA1B）情景下，全省采暖能耗将明显减少，但仍具有较大的不确定性．

研究全球气候变暖对林木生长的影响具有重要意义。以马尾松种源区域试验测定材料为例尝试预测气候变暖对我国林木生长的效应。根据Ｓｃｈｍｉｄｔｌｉｎｇ’ｓ回归法预测，若年均温提高２℃，马尾松９年生树高生长将下降８％左右。作者认为回归法有其固有缺点而难以确切说明气候变暖的效果。鉴于此，本文参照Ｍａｔｙａｓ’ｓ生长反应模型和作者已有研究基础，构建不同种源在年均温环境梯度的反应函数，确定增温后不同地理区域树高生

Climate warming, one of the main features of global change, has exerted indelible impacts on the environment, among which the impact on the transport and fate of pollutants has aroused widespread concern. Persistent organic pollutants （POPs） are a class of pollutants that are transported worldwide. Determining the impact of climate warming on the global cy- cling of POPs is important for understanding POP cycling processes and formulating relevant environmental policies. In this review, the main research findings in this field over the past ten years are summarized and the effects of climate warming on emissions, transport, storage, degradation and toxicity of POPs are reviewed. This review also summarizes the primary POP fate models and their application. Additionally, research gaps and future research directions are identified and suggested. Un- der the influence of climate change, global cycling of POPs mainly shows the following responses. （1） Global warming direct- ly promotes the secondary emission of POPs; for example, temperature rise will cause POPs to be re-released from soils and oceans, and melting glaciers and permafrost can re-release POPs into freshwater ecosystems. （2） Global extreme weather events, such as droughts and floods, result in the redistribution of POPs through intense soil erosion. （3） The changes in at- mospheric circulation and ocean currents have significantly influenced the global transport of POPs. （4） Climate warming has altered marine biological productivity, which has changed the POP storage capacity of the ocean. （5） Aquatic and terrestrial food-chain structures have undergone significant changes, which could lead to amplification of POP toxicity in ecosystems. （6） Overall, warming accelerates the POP volatilization process and increases the amount of POPs in the environment, although global warming facilitates their degradation at the same time. （7） Various models have predicted the future environmental be- haviors of POPs. These models are used to assist governments in comprehensively considering the impact of global warming on the environmental fate of POPs and therefore controlling POPs effectively. Future studies should focus on the synergistic effects of global changes on the cycling of POPs. Additionally, the interactions among global carbon cycling, water cycling and POP cycling will be a new research direction for better understanding the adaptation of ecosystems to climate change.

Climate changes in 21st century China are described based on the projections of 11 climate models under Representative Concentration Pathway （RCP） scenarios. The results show that warming is expected in all regions of China under the RCP scenarios, with the northern regions showing greater warming than the southern regions. The warming tendency from 2011 to 2100 is 0.06°C/10 a for RCP2.6, 0.24°C/10 a for RCP4.5, and 0.63°C/10 a for RCP8.5. The projected time series of annual temperature have similar variation tendencies as the new greenhouse gas （GHG） emission scenario pathways, and the warming under the lower emission scenarios is less than under the higher emission scenarios. The regional averaged precipitation will increase, and the increasing precipitation in the northern regions is significant and greater than in the southern regions in China. It is noted that precipitation will tend to decrease in the southern parts of China during the period of 2011–2040, especially under RCP8.5. Compared with the changes over the globe and some previous projections, the increased warming and precipitation over China is more remarkable under the higher emission scenarios. The uncertainties in the projection are unavoidable, and further analyses are necessary to develop a better understanding of the future changes over the region.

Based on the historical and RCP8.5 runs of the multi-model ensemble of 32 models participating in CMIP5, the present study evaluates the formation mechanisms for the patterns of changes in equatorial Pacific SST under global warming. Two features with complex formation processes, the zonal E1 Nifio-like pattern and the meridional equatorial peak warm- ing （EPW）, are investigated. The climatological evaporation is the main contributor to the E1 Nifio-like pattern, while the ocean dynamical thermostat effect plays a comparable negative role. The cloud-shortwave-radiation-SST feedback and the weakened Walker circulation play a small positive role in the E1 Nifio-like pattern. The processes associated with ocean dynamics are confined to the equator. The climatological evaporation is also the dominant contributor to the EPW pattern, as suggested in previous studies. However, the effects of some processes are inconsistent with previous studies. For example, changes in the zonal heat advection due to the weakened Walker circulation have a remarkable positive contribution to the EPW pattern, and changes in the shortwave radiation play a negative role in the EPW pattern.

Northeastern China has the second largest expanse of permafrost in China,primarily known as Xing＇an-Baikal permafrost.Located on the southeastern edges of the Eurasian cryolithozone,the permafrost is thermally unstable and ecologically sensitive to external changes.The combined impacts of climatic,environmental,and anthropogenic changes cause 3-dimensional degradation of the permafrost.To predict these changes on the southern limit and ground temperature of permafrost in Northeastern China,an equivalent latitude model （ELM） for the mean annual ground surface temperature （MAGSTs） was proposed,and further improved to take into account of the influences of vegetation and snow-cover based on observational data and using the SHAW model.Using the finite element method and assuming a climate warming rate of 0.048°C a-1,the ELM was combined with the unsteady-state heat conduction model to simulate permafrost temperatures at present,and to predict those after 50 and 100 a.The results indicate that at present,sporadic permafrost occurs in the zones with MAGSTs of 1.5°C or colder,and there would still be a significant presence of permafrost in the zones with the present MAGSTs of 0.5°C or colder after 50 a,and in those of-0.5°C or colder after 100 a.Furthermore,the total areal extent of permafrost would decrease from 2.57×105 km2 at present to 1.84×105 km2 after 50 a and to 1.29×105 km2 after 100 a,i.e.,a reduction of 28.4% and 49.8% in the permafrost area,respectively.Also the permafrost would degrade more substantially in the east than in the west.Regional warming and thinning of permafrost would also occur.The area of stable permafrost （mean annual ground temperature,or MAGT≤-1.0°C） would decrease from present 1.07×105 to 8.8×104 km2 after 50 a,and further decrease to 5.6×104 km2 after 100 a.As a result,the unstable permafrost and seasonally frozen ground would expand,and the southern limit of permafrost would shift significantly northwards.The changes in the permafrost environment may adversely affect on ecological environments and engineering infrastructures in cold regions.Avoidance of unnecessary anthropogenic changes in permafrost conditions is a practical approach to protect the permafrost environment.

This study identifies a decadal shift of summer surface air temperature （SAT） over Northeast Asia,including southeastern parts of Russia,Mongolia and northern China,around the mid-1990s.The results suggest that the SAT over the Northeast Asia experienced a significant warming after 1994 relative to that before 1993.This decadal shift also extends to northern China,and leads to a warmer summer over Northeast China and North China after the mid-1990s.The decadal warming over Northeast Asia is found to concur with the enhancement of South China rainfall around the mid-1990s.On the one hand,both the Northeast Asian SAT and South China rainfall exhibit this mid-1990s decadal shift only in summer,but not in other seasons.On the other hand,both the Northeast Asian SAT and South China rainfall exhibit this mid-1990s decadal shift not only in the summer seasonal mean,but also in each month of summer （June,July and August）.Furthermore,the decadal warming is found to result from an anticyclonic anomaly over Northeast Asia,which can be interpreted as the response to the increased precipitation over South China,according to previous numerical results.Thus,we conclude that the warming shift of summer Northeast Asian SAT around the mid-1990s was a remote response to the increased precipitation over South China.

We present the first millennial-length gridded field reconstruction of annual temperature for China, and analyze the reconstruction for spatiotemporal changes and associated uncertainties, based on a network of 415 well-distributed and accurately dated climatic proxy series.The new reconstruction method is a modified form of the point-by-point regression （PPR） approach.The main difference is the incorporation of the ＂composite plus scale＂ （CPS） and ＂Regularized errors-in-variables＂ （EIV） algorithms to allow for the assimilation of various types of the proxy data.Furthermore, the search radius is restricted to a grid size; this restriction helps effectively exclude proxy data possibly correlated with temperature but belonging to a different climate region.The results indicate that： 1） the past temperature record in China is spatially heterogenic, with variable correlations between cells in time; 2） the late 20th century warming in China probably exceeds mean temperature levels at any period of the past 1000 years, but the temperature anomalies of some grids in eastern China during the Medieval climate anomaly period are warmer than during the modern warming; 3） the climatic variability in the eastern and western regions of China was not synchronous during much of the last millennium, probably due to the influence of the Tibetan Plateau.Our temperature reconstruction may serve as a reference to test simulation results over the past millennium, and help to finely analyze the spatial characteristics and the driving mechanism of the past temperature variability.However, the lower reconstruction skill scores for some grid points underline that the present set of available proxy data series is not yet sufficient to accurately reconstruct the heterogeneous climate of China in all regions, and that there is the need for more highly resolved temperature proxies, particularly in the Tibetan Plateau.