Water-vapor source shift of Xinjiang region during the recent twenty years

The aim of this paper is to investigate the climate water-vapor sources of Xinjiang region and their shifts during the past 20 years. First, the principle and steps are roughly regulated to seek the water-vapor sources. Second, the climate stationary water-vapor transport in troposphere is calculated to distinguish where the water vapor comes from by ERA-40 reanalysis. In addition, the collocation between the transport and the atmospheric column water vapor content is analyzed. The results show that the major vapor comes from the west side of Xinjiang for mid-month of seasons, apart from July while the water vapor comes from the north or northwest direction. The water vapor sources are different for different seasons, for example, the Caspian Sea and Mediterranean are the sources in January and April, the North Atlantic and the Arctic sea in July, and the Black Sea and Caspian Sea in October, respectively. In recent ten years more water vapor above Xinjiang comes from the high latitudes and the Arctic sea with global warming, and less from Mediterranean in comparison with the case of 1973—1986. In fact, the air over subtropics becomes dry and the anomalous water vapor transport direction turns to west or southwest during 1987—2000. By contrast, the air over middle and high latitudes is warmer and wetter than 14 years ago.     

陕西渭北旱塬近43年气候暖干化研究

利用 1 95 5 - 1 997年陕西渭北地区 5个县、市的气温和降水资料 ,对近 43年来陕西渭北地区气候变化特征进行了分析 .结果表明 ,近 43年来 ,陕西渭北地区温度、降水的变化呈明显多重周期波动 ,年平均气温上升 ,降水量减少 ,变旱趋势明显 ,气候呈暖干化     

近50ａ来南疆气候变化对可利用降水量的影响

选择1951~2006年逐月降水和温度资料,计算出南疆年平均蒸发量及可利用降水量.在详细分析了50 a来南疆地区降水、气温、蒸发及可利用降水量变化特征的基础上,采用逐步回归周期分析法对降水、气温和可利用降水量进行了模拟,并对未来5 a上述要素进行了预测.结果表明,20世纪70年代以后南疆地区的温度、降水和蒸发变化基本呈上升态势,可利用降水量却呈现出偏多和偏少交替的波状变化特征.这说明气候变暖,可利用降水量不一定增多,未来5 a南疆地区可利用降水量将可能减少.     

长江源区未来气候变化情景降尺度

利用台站资料,从气候场的平均态、空间结构、变化趋势以及年内、年际变化方面对IPCC AR4中19个全球气候模式模拟结果及其集合平均在长江源区1961-1999年气温和降水的模拟能力进行了对比,从中优选了CGCM3.1_T47,MRI_CGCM2.3.2,UKMO-HadCM3及MME 18对流域气温和降水模拟较好的模式.然后再利用2000-2009年的台站观测资料分别对四个模式采用差值法和统计降尺度方法进行对比.最后,分别采用Delta和SD方法预估了长江源区21世纪2011-2030年、2031-2060年、2061-2090年A2情景下气温和降水的变化情景.在未来三个时期长江源区将明显增温,多年平均气温将分别升高1.5(1.2～1.9)℃,2.6(2.3～3.2)℃,4.5(3.7～5.3)℃;多年降水呈现微弱的增加趋势,增加幅度分别为9.1％(3.1％～12.7％),11.2％(4 6％～18.2％),15.7％(3.0％～26.3％).     

河北怀来盆地近60a气候变化特征及其影响

利用河北省怀来县1954—2012年月气象数据,采用线性倾向率法,距平法和Mann-Kendall趋势检验方法揭示了当地的气候变化特征;并分析了气候变化对水库来水量和粮食单产的关系.结果表明:1)近60年来,怀来县气候倾向率为0.36℃·(10a)-1,高于全国平均水平,年降水量呈下降趋势;从季节来看,四季气温均呈上升趋势,降水变化趋势存在差异,四季中以夏季暖干化趋势最明显.2)研究区年和四季年代均温都在1980—1989年开始变暖;年降水自1980—1989年开始减少,四季降水量的年代变化差异较大.3)研究区小区域尺度上的气候变化趋势与北方较大区域和全国尺度上的结果较为一致,并且暖干化趋势更加明显.4)气候要素与水库来水量和粮食单产显著相关,气候暖干化将加剧研究区水库来水锐减和粮食单产较低的问题.     

Impacts of climate warming on plants phenophases in China for the last 40 years

Based on plant phenology data from 26 stations of the Chinese Phenology Observation Network of the Chinese Academy of Sciences and the climate data, the change of plant phenophase in spring and the impact of climate warming on the plant phenophase in China for the last 40 years are analyzed. Furthermore, the geographical distribution models of phenophase in every decade are reconstructed, and the impact of climate warming on geographical distribution model of phenophase is studied as well. The results show that (ⅰ) the response of phenophase advance or delay to temperature change is nonlinear. Since the 1980s, at the same amplitude of temperature change, phenophase delay amplitude caused by temperature decrease is greater than phenophase advance amplitude caused by temperature increase; the rate of phenophase advance days decreases with temperature increase amplitude, and the rate of phenophase delay days increases with temperature decrease amplitude. (ⅱ) The geographical distribution model between phenophase and geographical location is unstable. Since the 1980s, with the spring temperature increasing in the most of China and decreasing in the south of Qinling Mountains, phenophases have advanced in northeastern China, North China and the lower reaches of the Changjiang River, and have delayed in the eastern part of southwestern China and the middle reaches of the Changjiang River; while the rate of the phenophase difference with latitude becomes smaller.     

近50年来柴达木盆地升温与全球变暖

柴达木盆地地处亚欧大陆腹地，是亚洲大陆干极核心，处于中纬西风带和东亚季风系统的交界带，对气候变化极为敏感。本文利用柴达木盆地五个气象站的资料，分析柴达木盆地气温变化，发现盆地气温显著上升，近50年来上升了2℃左右，远远大于全球上世纪升温0．6℃～0．7℃的水平。笔者推测柴达木盆地深居青藏高原内陆，青藏高原对全球气候变化有很高的敏感性，不仅迅速地响应全球变化的信号，而且对某些信号和趋势起着放大作用，还可能通过各种正反馈过程，对全球气候变化产生重大影响。     

基于BCSD降尺度方法的黄河源区气候变化预测

采用BCSD降尺度方法,根据黄河源区16个气象站基准期(1961—1990年)的逐日降水量、气温,最高气温和最低气温资料,对IPCCAR4 中的20个GCM模式在A1B情景下的气象资料进行降尺度研究,并简单论证了BCSD的降尺度效果及其结果的可信性。基于降尺度分析结果,预测在A1B情景下,黄河源区温度普遍升高,增幅约为0.032 ℃／a,降水量呈现波动状微弱上升趋势,增幅约为0.50 mm／a,同时从流域空间分布上看,东南部降水和气温的增加效果显著,一定程度上可认为黄河源区东南部有暖湿化的演变趋势。     

新余市51年气温变化特征分析

根据新余观测站1959~2009年的气温资料,从年平均气温、夏季、冬季平均气温和年平均最高气温、年平均最低气温趋势变化角度对新余51年的气温变化作了全面分析。分析表明：新余市51年来年平均气温、年平均最高气温、年平均最低气温都呈上升趋势,90年代中期之后增温尤其明显。夏季、冬季气温趋势变化中,夏季变暖趋势不明显,冬季变暖趋势显著。     

全球气候变化对中国自然灾害的可能影响

随着人口增多和社会经济的发展，全球CO2、CH4、N2O等气体的排放增加所引起的温室效应，预期本世纪的全球变暖较20世纪更为强烈．讨论了全球气候变化及其对中国自然灾害的可能影响．结果表明，本世纪全球气候进一步变暖将可能导致我国北方干旱趋势仍将延续．南方雨量增加特别是暴雨和台风的增加，会使洪涝灾害扩大加剧．沿海地区由于海平面上升，海岸带灾害主要是风暴潮呈现加剧趋势、农林病虫害、滑坡与泥石流、水土流失与土壤侵蚀灾害也将发展，唯寒冻灾害可能大幅度减轻．面对全球气候变化，我国政府及科学界应加强科学研究，积极参与国际合作，采取减轻、防范和适应措施，以减少经济损失．     

Response of water budget to recent climatic changes in the source region of the Yellow River

Discharge in the source region of the Yellow River significantly declined after 1990.China Meteorological Administration(CMA) data show that precipitation in this region was low in the 1990s but returned to above normal after 2002;in recent decades there has been rapid warming of surface air,moistening and wind speed decrease.To investigate the influences of recent climatic changes on the water budget,this study simulates the surface water budget at CMA stations within and surrounding the source region during 1960-2006,using an improved land surface model.Results indicate that the spatial pattern of precipitation change is an important factor(except for precipitation amount and intensity) in determining the response of runoff to precipitation changes.Low runoff in the 1990s was consistent with precipitation amount and intensity.The recovery of precipitation after 2002 is mainly from increased precipitation in the dry area of the source region.Evaporation was mainly limited by water availability in this dry area,and thus most of the precipitation increase was evaporated.By contrast,energy availability was a more important influence on evaporation in the wet area.There was more evaporation in the wet area because of rapid warming,although precipitation amount partly decreased and partly increased,contributing to the reduction of runoff after 2002.This control on evaporation and its response,together with the modified spatial pattern of precipitation,produced a water budget unfavorable for runoff generation in the source region during recent years.     

新疆石河子莫索湾垦区气候特征分析

利用莫索湾垦区1959-2007年历年日平均气温、最高(低)气温、降水量等资料,分析该地区48年年际、年代际、四季及近10年的气候变化特征,并得出了相关的结论.     

全球变暖与沼泽生态系统的研究进展

从三个方面综述了目前关于全球变暖与沼泽生态系统的研究:①全球变暖已经成为无法争辩的事实;②沼泽是各种主要温室气体的源和汇,因而在全球气候变化中有着特殊的地位和作用;③全球气候变化又有可能对沼泽生态系统的面积、分布、功能和结构等造成巨大的影响,也可能对气候系统形成负反馈.并针对已有的研究进展总结了国内外研究的不足.     

全球变暖背景下大连地区寒潮活动的气候变化

利用1961~2005年大连地区6个气象观测站的逐日平均气温、最低气温和最大平均风力资料,分析近45年大连地区寒潮活动的气候特征,着重研究大连地区寒潮的年代际、年际变化.结果表明:大连地区寒潮活动各地差异较大,南部开始早,结束晚;东部开始晚,结束早.大连地区寒潮主要出现在11、12月和1月.近45年来,大连地区寒潮异常具有三次跃变,跃变发生在20世纪70年代中期、80年代中后期和21世纪初期.大连的寒潮活动也可以分为四个阶段:活跃期—沉寂期—正负振荡期—沉寂期.近45年来,大连地区寒潮活动具有减少的趋势,从1961~2005年,趋势性寒潮频数减少为0.7次/10年.     

近50年来浙江宁波地区高温期水热变化研究———以宁波市鄞州站为例

本文选取1961—2013年宁波鄞州气象站地面观测数据,运用趋势分析、突变分析、相关性分析等方法,开展宁波地区高温期水热变化研究.得出以下结论:1)自1961年以来,宁波地区高温期温度和降水呈缓慢上升的趋势,相对湿度出现明显下降,其中温度上升是导致该地区相对湿度下降的主要因素;2)相对湿度变化在20世纪末、21世纪初出现突变,突变后相对湿度下降更加明显,有明显向"暖干"气候转变的趋势;3)2000—2013年,高温天气下的温度与相对湿度呈现明显的负相关,温度与相对湿度的相关系数达到了历史最高值0.633.高温天气成为近10年来相对湿度明显下降的决定性因素.     

近50年吉林省干湿指数时空分布特征分析

采用桑斯维特在气候分类法中定义的干湿指数,结合趋势系数分析、小波分析、M-K检验等统计方法,对吉林省近50年气候干湿变化状况进行了分析,结果表明:吉林省表现出4次相对的干湿交替,即20世纪60年代的偏湿润期,70年代的相对干旱期,80年代的偏湿润期,90年代中后期以后的偏干旱期;存在10～15 a和3a的变化周期,突变发生在1979- 1980年;在空间变化上表现出湿润区范围不断扩大,半湿润区显著缩小,半干旱区范围略有扩大的特点.     

近60年来中国大陆降水、气温动态及其相互关系的初步研究

采用统计学方法,依据中国22个水文站点的资料,作出近60年来降水和气温的动态图,对22幅图逐个进行综合评价,并对降水和气温之间的相关关系进行分析,得出如下主要结论：a. 中国近60年来降水表现为波动变化,年际间有增有减,各不相同,无统一增减趋势;b. 气温变化亦呈波动状态,近10～20年期间多数站点气温确有增高趋势,但有些站点却表现为下降趋势,得不出统一变暖的结论;c. 从降水与气温的相互影响来看,在降水多的时段或年份气温偏低,但也有相反情况,因而得不出由于气温升高,降水量统一增加或统一减少的结论;d.     

Climate instability in the Yili region, Xinjiang during the last glaciation

The climate is influenced by westerlies year in year out and the aeolian loess is widespread in the Yili region, the Xinjiang Uygur Autonomous Region. Through the study of the loess section with a thickness of 21.5 m, much useful information about climatic change in this region during the last glaciation was gotten. Grain size analysis of loess samples in the section showed that the climatic change in the Yili region was of instability during the last glaciation and similar to those of the North Atlantic Ocean and Greenland. In correspondence with the Heinrich events, the percentage of the size fraction of loess with grain size less than 10 μm decreased in cold stadials in the Yili region. This result suggests that the westerly wind be strengthened during the cold periods. Compared with the stadials, the content of the loess with grain size less than 10 μm was increased in interstadials, which indicated that the strength of the westerly wind was weakened. It is obvious that the climate was instable not only in the North Atlantic Ocean and polar regions, but also in other areas of Northern Hemisphere during the last glaciation.     

增温对疏勒河上游流域高寒草地物候期的影响

2012年5月中旬至9月中旬,在疏勒河上游流域高寒草地上开展的增温实验结果表明:不论在原生草地、退化草地还是翻耕草地样方内,增温罩的存在大大提前了草地的返青期,同时增温使得退化和翻耕草地上的植被花期也有所提前;从涡动观测结果来看,2011年的生长旺盛期和达到最大值的日期较2010年提前了15 d左右;2011年枯黄期较2010年稍有提前.