CHARACTERISTICS OF CLIMATE WARMING AND IMPACT ON CLIMATE ZONES CHANGE IN GUANGDONG

Based on temperature data in Guangdong in the past 50years, statistical methods are used to analyze the characteristics of temperature in spatial and temporal variation. The results show that land surface temperature warms by 0.16 °C/10a in Guangdong. The range of warming was lower than the average of nationwide and global land surface. Furthermore, the temperature has a larger increase tendency in winter and spring and coastal areas than in summer and autumn and inland areas. Climate zones move towards the north obviously. North tropical zone is expanding, south subtropical zone is reducing and central subtropical zone is relatively stable. Under the global climate warming, characteristics of climate warming in Guangdong were influenced by atmosphere general circulation, sea surface temperature and human activities etc.     

热带太平洋年代际平均气候态变化与ENSO循环

文中用观测的热带太平洋海表温度资料、风应力资料和OLR资料，通过多时间尺度分析，将与ENSO有关的变化分为3个主要的分量，一是2～7a的ENSO循环尺度，二是8～20a的年代际尺度，三是20a以上的平均气候态变化。讨论了热带太平洋这种平均气候态变化的主要特征以及与ENSO循环的关系，并用耦合模式的数值试验来研究平均气候态的变化对ENSO循环的影响。结果表明热带太平洋的平均气候态在20世纪70年代后期发生了一次由冷态向暖态的变化，主要增暖区是沿赤道以及热带东太平洋的，海表温度变化最大中心可以达到0.6℃。伴随着海表温度的变化，赤道西太平洋的西风距平加强，赤道东太平洋的东风距平也加强，在赤道中太平洋形成了一个加强的辐合中心。年代际平均气候冷暖态的变化对ENSO最直接的线性影响是使ElNio位相增加，而形成ENSO冷位相和暖位相的不对称。另一方面较暖的平均气候态可能引起海洋和大气之间的耦合加强，导致ENSO循环振荡有所加强。     

气候变暖对河西走廊中部农业的影响

选取河西走廊中部张掖市6县（区）1961～2006年日平均气温、日最低气温、年降水资料。计算历年各地气温、积温、无霜冻期和农业气候生产力,分析河西走廊中部气候变暖对农业生产的影响。结果表明：20世纪80年代末期以来,河西走廊中部气温呈持续升高趋势,1987～2006年的平均气温明显增高,且冬季升温幅度最为显著,秋季次之,春、夏季升温幅度较小;≥0℃和≥10℃积温增多,无霜冻期延长,气候生产力增加。80年代后期气候明显变暖,喜温作物面积扩大,复种指数提高,有利于冬季大棚蔬菜等设施农业的生产;干旱发生频率加大,病虫越冬存活率上升,导致农业生产成本增加。     

近50年全球气候变暖对珠江口海平面变化趋势的影响

根据1957～2006年全球温度和珠江口验潮站平均潮位资料,分析全球气候变暖与珠江口平均海平面上升的关系,并对2030年珠江口海平面上升幅度作出预测。结果表明,近50年来珠江口海平面的上升趋势与全球气候变暖存在显著的正相关关系,预测2030年（前后）珠江口平均海平面比1980～1999年高13～17cm。     

气候增暖对广东省植物物候变化的影响

根据广东省气象观测资料和10个农业气象观测站的物候观测资料,分析了1982~2004年温度变化对广东省木本植物物候变化的影响,并建立了物候期差异与温度之间的关系模式,分析了当前气候增暖背景下物候期对温度变化的响应关系。结果表明:平均温度上升,木本植物春季物候期提前;平均温度下降,木本植物春季物候期推迟。物候期的提前与推迟对温度的上升与下降的响应是非线性的。在同等升降温幅度情况下,降温导致的物候期推迟幅度较升温导致的物候期提前幅度大。     

近百年气候变暖与珠江口最高潮位变化的关系

在收集珠江口广东省境内查测台风暴潮位(高)潮位历史资料、4个验潮站年最高潮位资料和香港特区北角/鰂魚涌重现期≥2年台风最高潮位资料的基础上,对比分析其与同期全球温度距平的关系,得出1910～2009年问珠江口每年最高潮位变化与全球气候变暖之间不存在明显的相关关系.     

Sensitivity of climate change projections to uncertainties in the estimates of observed changes in deep-ocean heat content

The MIT 2D climate model is used to make probabilistic projections for changes in global mean surface temperature and for thermosteric sea level rise under a variety of forcing scenarios. The uncertainties in climate sensitivity and rate of heat uptake by the deep ocean are quantified by using the probability distributions derived from observed twentieth century temperature changes. The impact on climate change projections of using the smallest and largest estimates of twentieth century deep ocean warming is explored. The impact is large in the case of global mean thermosteric sea level rise. In the MIT reference (“business as usual”) scenario the median rise by 2100 is 27 and 43 cm in the respective cases. The impact on increases in global mean surface air temperature is more modest, 4.9 and 3.9 C in the two respective cases, because of the correlation between climate sensitivity and ocean heat uptake required by twentieth century surface and upper air temperature changes. The results are also compared with the projections made by the IPCC AR4’s multi-model ensemble for several of the SRES scenarios. The multi-model projections are more consistent with the MIT projections based on the largest estimate of ocean warming. However, the range for the rate of heat uptake by the ocean suggested by the lowest estimate of ocean warming is more consistent with the range suggested by the twentieth century changes in surface and upper air temperatures, combined with the expert prior for climate sensitivity.     

海洋环流对全球增暖趋势的调制：基于FGOALS-s2的数值模拟研究

在工业革命以来全球长期增暖趋势背景下,全球平均表面气温还同时表现出年代际变化特征,二者叠加在一起使得全球平均气温在某些年份增暖相对停滞(如1999～2008年)或者增暖相对较快(如1980～1998年).利用中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室(LASG)发展的耦合气候模式FGOALS-s2历史气候和典型路径浓度(RCPs)模拟试验结果研究了可能造成全球增暖的年代际停滞及加速现象的原因,特别是海洋环流对全球变暖趋势的调制作用.该模式模拟的全球平均气温与观测类似,即在长期增暖趋势之上,还叠加了显著的年代际变化.对全球平均能量收支分析表明,模拟的气温年代际变化与大气顶净辐射通量无关,意味着年代际表面气温变化可能与能量在气候系统内部的重新分配有关.通过对全球增暖加速和停滞时期大气和海洋环流变化的合成分析及回归分析,发现全球表面气温与大部分海区海表温度(SST)均表现出几乎一致的变化特征.在增暖停滞时期,SST降低,更多热量进入海洋次表层和深层,使其温度增加;而在增暖加速时期,更多热量停留在表层,使得大部分海区SST显著增加,次表层海水和深海相对冷却.进一步分析表明,热带太平洋表层和次表层海温年代际变化主要是由于副热带—热带经圈环流(STC)的年代际变化所致,然后热带太平洋海温异常可以通过风应力和热通量强迫作用引起印度洋、大西洋海温的年代际变化.在此过程中,海洋环流变化起到了重要作用,例如印度尼西亚贯穿流(ITF)年代际异常对南印度洋次表层海温变化起到关键作用,而大西洋经圈翻转环流(AMOC)则能直接影响到北大西洋深层海温变化.     

Reduced Sensitivity of Tropical Cyclone Intensity and Size to Sea Surface Temperature in a Radiative-Convective Equilibrium Environment

It has been challenging to project the tropical cyclone(TC) intensity,structure and destructive potential changes in a warming climate.Here,we compare the sensitivities of TC intensity,size and destructive potential to sea surface warming with and without a pre-storm atmospheric adjustment to an idealized state of Radiative-Convective Equilibrium(RCE).Without RCE,we find large responses of TC intensity,size and destructive potential to sea surface temperature(SST) changes,which is in line with some previous studies.However,in an environment under RCE,the TC size is almost insensitive to SST changes,and the sensitivity of intensity is also much reduced to 3%?C-1–4%?C-1.Without the pre-storm RCE adjustment,the mean destructive potential measured by the integrated power dissipation increases by about 25%?C-1 during the mature stage.However,in an environment under RCE,the sensitivity of destructive potential to sea surface warming does not change significantly.Further analyses show that the reduced response of TC intensity and size to sea surface warming under RCE can be explained by the reduced thermodynamic disequilibrium between the air boundary layer and the sea surface due to the RCE adjustment.When conducting regional-scale sea surface warming experiments for TC case studies,without any RCE adjustment the TC response is likely to be unrealistically exaggerated.The TC intensity–temperature sensitivity under RCE is very similar to those found in coupled climate model simulations.This suggests global mean intensity projections under climate change can be understood in terms of a thermodynamic response to temperature with only a minor contribution from any changes in large-scale dynamics.     

Climate change: changing means and changing extremes

Ongoing global warming not only involves changes in temperature and the global mean; it affects more or less every part of the climate. Regional temperature changes are often greater or smaller than corresponding changes in the global mean. In some cases the direction of change may also be different. For example, temperature changes are higher over land than over the ocean. Precipitation increases in some regions but decreases in others. Changes in extreme events may differ from changes in the corresponding mean. Present scientific knowledge clearly indicates that the already observed global trend towards warmer conditions will continue and that it will be accompanied by changes in yet other aspects of climate. This paper highlights, as a brief review, aspects of our changing climate from the available scientific knowledge with a bearing on the energy sector. Its focus is on temperature and precipitation, with some consideration of wind and sea level, among others. While uncertainties remain as far as the magnitude of future global-scale changes is concerned, and even more so their many regional patterns, significant changes are foreseen in, for example, global and regional temperature and precipitation, sea level rise, and in the characteristics of various extreme events.     

近54年广东沿海海表温度最低、最高年平均成因分析

根据1960—2013年广东省沿海5个海洋站的实测月平均海表温度（SST）及南海高压特征指数、太阳总辐射、季风、全球年平均地表温度距平等资料,采用比较方法,分析近54年最低、最高年平均SST的季节变化差异及其形成原因,得出近54年来年平均最低、最高SST分别为1984年（SST距平为-0.95℃）与2002年（距平为＋0.91℃）;SST差异主要发生于冬、春季月份,其形成原因与全球变暖、南海高压强弱变化、太阳总辐射强度、冬季风强度等季节变化有密切关系。     

气候变暖对中国不同地区农业的影响

摘要：利用国家统计局《中国农村统计年鉴》1984-2003年的数据和同期年平均温度的观测数据,分析了我国不同地区20年间温度变化、农业生产资料投入以及播种面积变化对粮食总产的影响。结果表明,以温度升高为主要特征的气候变化对东北地区农作物增产有明显促进作用,对华北、西北和西南地区的农作物增产有一定抑制作用,对华东和中南地区的农作物粮食产量的影响则不明显。农业投入的增加对各地区的农作物增产在早期作用均显著,后期则增长缓慢。而各地区播种面积的变化对其总产量影响不太明显,但华东和中南地区农业播种面积的持续下降对粮食总产量有较大的抑制作用。     

Impact of Global Oceanic Warming on Winter Eurasian Climate

In the 20 th century, Eurasian warming was observed and was closely related to global oceanic warming(the first leading rotated empirical orthogonal function of annual mean sea surface temperature over the period 1901–2004). Here, large-scale patterns of covariability between global oceanic warming and circulation anomalies are investigated based on NCEP–NCAR reanalysis data. In winter, certain dominant features are found, such as a positive pattern of the North Atlantic Oscillation(NAO), low-pressure anomalies over northern Eurasia, and a weakened East Asian trough. Numerical experiments with the CAM3.5, CCM3 and GFDL models are used to explore the contribution of global oceanic warming to the winter Eurasian climate. Results show that a positive NAO anomaly, low-pressure anomalies in northern Eurasia, and a weaker-than-normal East Asian trough are induced by global oceanic warming. Consequently, there are warmer winters in Europe and the northern part of East Asia. However, the Eurasian climate changes differ slightly among the three models. Eddy forcing and convective heating from those models may be the reason for the different responses of Eurasian climate.     

Arctic sea ice and Eurasian climate: A review

The Arctic plays a fundamental role in the climate system and has shown significant climate change in recent decades,including the Arctic warming and decline of Arctic sea-ice extent and thickness. In contrast to the Arctic warming and reduction of Arctic sea ice, Europe, East Asia and North America have experienced anomalously cold conditions, with record snowfall during recent years. In this paper, we review current understanding of the sea-ice impacts on the Eurasian climate.Paleo, observational and modelling studies are covered to summarize several major themes, including: the variability of Arctic sea ice and its controls; the likely causes and apparent impacts of the Arctic sea-ice decline during the satellite era,as well as past and projected future impacts and trends; the links and feedback mechanisms between the Arctic sea ice and the Arctic Oscillation/North Atlantic Oscillation, the recent Eurasian cooling, winter atmospheric circulation, summer precipitation in East Asia, spring snowfall over Eurasia, East Asian winter monsoon, and midlatitude extreme weather; and the remote climate response(e.g., atmospheric circulation, air temperature) to changes in Arctic sea ice. We conclude with a brief summary and suggestions for future research.     

Mechanisms for the land/sea warming contrast exhibited by simulations of climate change

The land/sea warming contrast is a phenomenon of both equilibrium and transient simulations of climate change: large areas of the land surface at most latitudes undergo temperature changes whose amplitude is more than those of the surrounding oceans. Using idealised GCM experiments with perturbed SSTs, we show that the land/sea contrast in equilibrium simulations is associated with local feedbacks and the hydrological cycle over land, rather than with externally imposed radiative forcing. This mechanism also explains a large component of the land/sea contrast in transient simulations as well. We propose a conceptual model with three elements: (1) there is a spatially variable level in the lower troposphere at which temperature change is the same over land and sea; (2) the dependence of lapse rate on moisture and temperature causes different changes in lapse rate upon warming over land and sea, and hence a surface land/sea temperature contrast; (3) moisture convergence over land predominantly takes place at levels significantly colder than the surface; wherever moisture supply over land is limited, the increase of evaporation over land upon warming is limited, reducing the relative humidity in the boundary layer over land, and hence also enhancing the land/sea contrast. The non-linearity of the Clausius–Clapeyron relationship of saturation specific humidity to temperature is critical in (2) and (3). We examine the sensitivity of the land/sea contrast to model representations of different physical processes using a large ensemble of climate model integrations with perturbed parameters, and find that it is most sensitive to representation of large-scale cloud and stomatal closure. We discuss our results in the context of high-resolution and Earth-system modelling of climate change.     

南极地区气候系统变化: 过去、现在和将来

 南极科学委员会（SCAR）下属的"南极与全球气候系统（AGCS）计划"专家委员会发布了"南极与南大洋气候系统（SASOCS）"白皮书,重点评估了过去50 a南极地区气候系统的变化并预估了未来100 a情景。白皮书总体认为,过去50 a南极气候系统变化表现出很强的区域特征。南极半岛地区升温明显,半岛及亚南极岛屿上的冰川均处于退缩状态;南半球环状模（SAM）转为正位相,西南极上空的暖湿气团入侵加强,南极冬季对流层有升温趋势,平流层变冷,极涡消退日期推迟;东南极外围的南极底层水变淡,Weddell海区的底层水有变暖趋势。虽有上述区域变化,整个南极地区在过去50 a中近地面气温并无明显升高,降水亦无明显增加。自20世纪80年代以来海冰面积也无明显变化,只在某些扇区变化强烈。模式预估结果为：到21世纪末南极内陆地区将增暖（3.4±1.0）℃, 海冰面积将缩小约30%。现有的冰盖模式尚不足以回答未来气候变暖情景下冰盖融化与海平面变化之间的定量关系,有待更深入研究。     

南极地区气候系统变化: 过去、现在和将来

南极科学委员会（SCAR）下属的"南极与全球气候系统（AGCS）计划"专家委员会发布了"南极与南大洋气候系统（SASOCS）"白皮书,重点评估了过去50 a南极地区气候系统的变化并预估了未来100 a情景。白皮书总体认为,过去50 a南极气候系统变化表现出很强的区域特征。南极半岛地区升温明显,半岛及亚南极岛屿上的冰川均处于退缩状态;南半球环状模（SAM）转为正位相,西南极上空的暖湿气团入侵加强,南极冬季对流层有升温趋势,平流层变冷,极涡消退日期推迟;东南极外围的南极底层水变淡,Weddell海区的底层水有变暖趋势。虽有上述区域变化,整个南极地区在过去50 a中近地面气温并无明显升高,降水亦无明显增加。自20世纪80年代以来海冰面积也无明显变化,只在某些扇区变化强烈。模式预估结果为：到21世纪末南极内陆地区将增暖（3.4±1.0）℃, 海冰面积将缩小约30%。现有的冰盖模式尚不足以回答未来气候变暖情景下冰盖融化与海平面变化之间的定量关系,有待更深入研究。     

全球、中国及云南近百年气温变化的层次结构和突变特征

用文献［１］建立的自适应多分辨数据波滤器进行了全球、中国及云南近百年气温变化的层次结构和突变特征分析。结果表明：（１）全球近百年来的气温变化对于较大时间尺度的演化来说主要特征是变暖,并为３个层次：即１９１９年以前的偏冷期;１９２０－１９７８年偏暖期和１９７９年以后的更暖期。对应于这种较大时间尺度的层次演变,全球的气温变化表现出十分明显的突变特征,两上最明显增暖的突变点分别发生在１９２０年和１９７９     

Winter crop sensitivity to inter-annual climate variability in central India

India is predicted to be one of the most vulnerable agricultural regions to future climate changes. Here, we examined the sensitivity of winter cropping systems to inter-annual climate variability in a local market and subsistence-based agricultural system in central India, a data-rich validation site, in order to identify the climate parameters to which winter crops – mainly wheat and pulses in this region – might be sensitive in the future. We used satellite time-series data to quantify inter-annual variability in multiple climate parameters and in winter crop cover, agricultural census data to quantify irrigation, and field observations to identify locations for specific crop types. We developed three mixed-effect models (250 m to 1 km scale) to identify correlations between crop cover (wheat and pulses) and twenty-two climate and environmental parameters for 2001-2013. We find that winter daytime mean temperature (November–January) is the most significant factor affecting winter crops, irrespective of crop type, and is negatively associated with winter crop cover. With pronounced winter warming projected in the coming decades, effective adaptation by smallholder farmers in similar landscapes would require additional strategies, such as access to fine-scale temperature forecasts and heat-tolerant winter crop varieties.     

Possible Impacts of Climate Change on Soil Moisture Availability in the Southeast Anatolia Development Project Region (GAP): An Analysis from an Agricultural Drought Perspective

This paper presents probable effects of climate change on soil moisture availability in the Southeast Anatolia Development Project (GAP) region of Turkey. A series of hypothetical climate change scenarios and GCM-generated IPCC Business-as-Usual scenario estimates of temperature and precipitation changes were used to examine implications of climate change for seasonal changes in actual evapotranspiration, soil moisture deficit, and soil moisture surplus in 13 subregions of the GAP. Of particular importance are predicted patterns of enhancement in summer soil moisture deficit that are consistent across the region in all scenarios. Least effect of the projected warming on the soil moisture deficit enhancement is observed with the IPCC estimates. The projected temperature changes would be responsible for a great portion of the enhancement in summer deficits in the GAP region. The increase in precipitation had less effect on depletion rate of soil moisture when the temperatures increase. Particularly southern and southeastern parts of the region will suffer severe moisture shortages during summer. Winter surplus decreased in scenarios with increased temperature and decreased precipitation in most cases. Even when precipitation was not changed, total annual surplus decreased by 4 percent to 43 percent for a 2°C warming and by 8 percent to 91 percent for a 4°C warming. These hydrologic results may have significant implications for water availability in the GAP as the present project evaluations lack climate change analysis. Adaptation strategies – such as changes in crop varieties, applying more advanced dry farming methods, improved water management, developing more efficient irrigation systems, and changes in planting – will be important in limiting adverse effects and taking advantage of beneficial changes in climate.