1961-2005年华东地区高温气候特征

Based on the daily maximum temperature data covering the period 1961-2005, temporal and spatial characteristics and their changing in mean annual and monthly high temperature days (HTDs) and the mean daily maximum temperature (MDMT) during annual and monthly HTDs in East China were studied. The results show that the mean annual HTDs were 15.1 and the MDMT during annual HTDs was 36.3℃ in the past 45 years. Both the mean annual HTDs and the MDMT during annual HTDs were negative anomaly in the1980s and positive anomaly in the other periods of time, oscillating with a cycle of about 12-15 years. The mean annual HTDs were more in the southern part, but less in the northern part of East China. The MDMT during annual HTDs was higher in Zhejiang, Anhui and Jiangxi provinces in the central and western parts of East China. The high temperature process (HTP) was more in the southwestern part, but less in northeastern part of East China. Both the HTDs and the numbers of HTP were at most in July, and the MDMT during monthly HTDs was also the highest in July. In the first 5 years of the 21st century, the mean annual HTDs and the MDMT during annual HTDs increased at most of the stations, both the mean monthly HTDs and the MDMT during monthly HTDs were positive anomalies from April to October, the number of each type of HTP generally was at most and the MDMT in each type of HTP was also the highest.     

华东地区夏季高温期的气候特征及其变化规律

基于华东气象站点1961-2005 年逐日最高地面气温资料, 分析了华东高温日数和高温 日平均最高气温的时空动态变化特征。结果表明: 过去45 年间, 华东年均高温日数为15.1 天, 高温日平均最高气温为36.3 ^oC, 高温以12~15 年为显著振荡周期, 在20 世纪80 年代为 弱负距平, 而在其他时期都为正距平。华东高温日数呈北少南多的空间分布, 高温日平均最 高气温以安徽、浙江和江西较高, 高温过程数是东北部少, 西南部多。高温日数和高温过程 数是以7 月最多, 高温日平均最高气温也是以7 月最高。在21 世纪最初5 年, 站点高温日数 和高温日平均最高气温增加, 4-10 月高温都为正距平, 各级高温过程数总体最多, 各级高温 过程日平均最高气温也最高。     

Climatic characteristics of high temperature in East China during 1961–2005

Based on the daily maximum temperature data covering the period 1961-2005, temporal and spatial characteristics and their changing in mean annual and monthly high temperature days（HTDs）and the mean daily maximum temperature（MDMT）during annual and monthly HTDs in East China were studied.The results show that the mean annual HTDs were 15.1 and the MDMT during annual HTDs was 36.3℃in the past 45 years.Both the mean annual HTDs and the MDMT during annual HTDs were negative anomaly in the1980s and positive anomaly in the other periods of time,oscillating with a cycle of about 12-15 years.The mean annual HTDs were more in the southern part,but less in the northern part of East China.The MDMT during annual HTDs was higher in Zhejiang,Anhui and Jiangxi provinces in the central and western parts of East China.The high temperature process（HTP） was more in the southwestern part,but less in northeastern part of East China.Both the HTDs and the numbers of HTP were at most in July,and the MDMT during monthly HTDs was also the highest in July.In the first 5 years of the 21st century,the mean annual HTDs and the MDMT during annual HTDs increased at most of the stations,both the mean monthly HTDs and the MDMT during monthly HTDs were positive anomalies from April to October,the number of each type of HTP generally was at most and the MDMT in each type of HTP was also the highest.     

华北主要城市夏季高温气候特征及评估方法

1 Introduction The major cities of North China are located in the warm extra-tropical belt and the semi-humid continental monsoon climate zone. Geographically, the Taihang Mountain to the northwest is a shield against invasion of cold air, although it is …     

Climatic characteristics of summer high temperature and assessment methods in the large cities of North China

Based on the high temperature data of June to August in 1961-2000 in North China, the high temperature weather processes are investigated, and a more complete data set for severe high temperature processes is created. The climatic characteristics of adverse high temperature weather in Beijing, Tianjin, Shijiazhuang, Jinan and Taiyuan are analyzed respectively. The major features of the East-Asia Subtropical High and Transformed Continental High are discussed. The outcomes indicate that the influence of both East Asia Subtropical High and Transformed Continental High on these weather events varies, by a larger margin, from one city to another over North China and they are also closely related to the relative humidity. It is found that the behaviours of East-Asia Subtropical High and Transformed Continental High are the major important systems that give rise to the summer high temperature weather over the region. Based on these findings, the 5-day, 10-day and monthly assessment models for such high impact events have been developed. The assessment outcomes prove to be useful in assessing severe high-temperature events in major cities of North China.     

1961-2005年新疆区域分级雨日(量)的气候特征

利用新疆区域108个常规气象观测站的逐日降雨资料对新疆区域1961-2005年分级雨日(量)的气候特征进行研究.按日雨量的大小分成4个等级:小雨(0.1～6.0 mm)、中雨(6.1～12.0 mm)、大雨(12.1～24.0 mm)和暴雨(≥24.1 mm),有效雨日(量)为上面4个等级雨日(量)的总和.结果发现:新...     

中国北方地区近50年来气温变化特征的研究

文章分析了1951~2000年中国北方地区(包括东北、华北和西北)的平均气温、日最高气温、日最低气温随时间的变化趋势特征。分析发现:在全球气候变暖的前景下,中国北方地区近50年来平均气温、日最高气温和日最低气温的增温态势十分明显;东北地区的增温大于西北和华北地区;日最低气温的增温比平均气温和日最高气温更加显著;冬季增温比夏季显著。20世纪80年代中后期平均气温、日最高气温、日最低气温大多发生了一次显著的变暖突变。90年代以来中国北方地区的气温明显偏高。但是不同季节、不同区域气温的多年变化特征并不完全相同,具有各自的特殊性。     

中国北方地区近50年来气温变化特征及其突变性

从1951-2000年中国北方地区(包括东北、华北和西北)的平均气温、日最高气温、日最低气温随时间的变化趋势特征来看。通过分析发现：在全球气候变暖的前景下,中国北方地区近50年来平均气温、日最高气温和日最低气温的增温态势十分明显;东北地区的增温大于西北和华北地区;日最低气温的增温比平均气温和日最高气温更加显著;冬季增温比夏季显著。20世纪80年代中后期平均气温、日最高气温、日最低气温大多发生了一次显著的变暖突变。90年代以来中国北方地区的气温明显偏高。但是不同季节、不同区域气温的多年变化特征并不完全相同,具有各自的特殊性。     

华北主要城市夏季高温气候特征及评估方法

利用我国华北地区1961~2000年夏季6~8月高温资料,探讨了华北地区主要城市高温过程,建立该地区强高温过程较完整的序列。分析华北主要城市北京、天津、石家庄、济南、太原市等夏季危害性高温气候特征。给出了东亚副热带高压和大陆变性高压的活动特点。观测结果表明,东亚副热带高压和大陆变性高压对华北地区主要城市夏季危害性高温在各地有很大差异,与相对湿度大小有密切关系。东亚副热带高压和大陆变性高压的活动是造成华北地区城市夏季危害性高温的主要影响系统。在此基础上建立了华北主要城市夏季危害性高温候、旬、月评估方法。其结果表明该方法对华北地区主要城市夏季危害性高温影响评估有应用价值。     

我国夏玉米潜在种植分布区的气候适宜性研究

根据我国188 个夏玉米农业气象观测站资料与1971-2000 年10 km×10 km空间分辨率的气候资料,结合国家层次和年尺度筛选出的影响我国玉米种植分布的潜在气候指标,利用最大熵(MaxEnt) 模型和ArcGIS空间分析技术,构建了我国夏玉米潜在种植分布与气候因子关系模型,研究了影响我国夏玉米潜在种植分布的主导气候因子及其气候适宜性。结果表明,影响我国夏玉米潜在种植分布的主导气候因子有：无霜期、年平均温度、≥ 10 oC积温持续天数、≥ 0 oC积温、≥ 10 oC积温、最冷月平均温度、最热月平均温度、年降水;采用夏玉米存在概率这一综合反映各主导因子作用的指标,将我国夏玉米潜在种植分布区划分为4 个等级：最适宜区、适宜区、次适宜区和不适宜区,并阐述了各气候适宜区的气候特征。研究结果可为夏玉米种植的科学布局及制定应对气候变化政策提供参考。     

华北地区高温日数的气候特征及变化规律

基于1960～2009年华北地区90个台站逐日最高气温数据,采用趋势分析等方法分析近50 a华北地区高温日数的时空变化特征。结果表明,近50 a华北地区高温日数以海拔高度800 m等值线为界呈现南多北少的分布特点,南部主要呈减少趋势,北部主要呈增加趋势。同时它显现出明显的"多-少-多"年代际变化特征,与1960年代相比,2000年代高温日数在7月稍增加,5和8月有所减少。近50 a华北地区累计高温过程频次呈微弱的减少趋势,南北部高温过程集中的年代和月份也有所不同。     

中国强降水过程时空集中度气候趋势

基于日降水资料序列提出一种度量不同强度降水过程时空集中程度的指标,根据中国740个气象站逐日降水资料研究分析了我国强降水过程集中度和集中期及其相关统计特征,结果表明暴雨过程年内集中度与年降水量正相关区与中国降水空间分布有很好的一致性;在对大范围洪涝灾害研究方面,暴雨过程年内集中度和集中期在定量地表征降水量在时空场上的非均匀性时有更高分辨力; 暴雨过程年内集中度比较清晰地反映出长江流域、江淮地区洪涝增加的趋势及黄河中下游、华北强降水减少的趋势。该方法可直接应用到评估水旱灾害及其气候影响等领域。     

中国强降水过程时空集中度气候趋势

1 Introduction Changes in climate variability and extrem es of weather and clim ate events have received increasing attention in the pastyears since these events have the strongestimpacton society. There hasbeen a widespread increase in heavy and extrem e…     

Climatic trends of different intensity heavy precipitation events concentration in China

Based on 740 stations of daily precipitation datasets in China, the precipitation- concentration degree (PCD) and precipitation-concentration period (PCP) of different intensity durative precipitation events were calculated to analyze their statistical characteristics, mainly including spatial and temporal distributions, variations and climatic trends of the two parameters of the durative heavy precipitation events in China. It is proved that these two parameters of heavy rainfall can display the temporal inhomogeneity in the precipitation field. And it is also found that there is a good positive relationship between the precipitation-concentration degree and annual rainfall amount in the Eastern and Central China. This method can be applied in flood assessment and climate change fields.     

中国西北干旱半干旱区年平均气温的时空变化规律分析

利用中国西北干旱区138个测站,近46年历年平均地面月气温资料,采用线性趋势分析、多项式拟合、EOF、REOF、Mann-Kendall、子波分析等方法,分析了干旱区年平均气温对气候变暖的响应.结果表明:(1)中国西北干旱半干旱区年平均气温近46年增温率为0.34℃/10 a.新疆西部、青海高原东部的部分地方受大地形背风坡影响有不显著的上升趋势,其余大部分区域增温显著,同步响应全球变暖.(2)年平均气温标准差分布不均匀.除南疆和海东-陇南-带相对较小,该区其余大部分区域年平均气温的年际变化稳定性差.(3)蒙陕甘宁-塔里木盆地是该区气温变化最敏感的区域.年平均气温的演变在干旱半干旱区一致性程度较高.从20世纪70年代初期开始发生降温-升温转型,1986年有一次显著突变,其后气温达到一个更显著的增暖时期;全区性的前10个偏热年,全部出现在20世纪90年代及以后,各分区的异常偏热年,大多数也出现在1990年以后;气温异常变化存在5年和10年左右的周期,从15年以上的变化层次来看,气温趋势还在偏高的位置.(4)年平均气温存在演变的地域差异,蒙新区和陕甘宁青区南北变化相反.(5)根据REOF分析将该区年平均气温异常细分为北部区、高原区、南疆区和东部区4个分区.西部干旱半干旱区年平均气温的转折存在区域差异,高原和南疆区单调增暖,无明显转折,北部区的转暖时间比较低纬度的东部大致要早5年左右.受高原"启动区"影响,其它区的突变比高原要晚3～10年,其它区的年代际变化比高原要晚1～2年.     

西北地区5—9月极端干期长度异常的气候特征

利用西北地区107个测站1960—2004年逐日降水资料,统计5—9月连续无雨日数 (日降水量小于0.1 mm),得到西北地区5—9月的逐年极端干期长度,在此基础上分析了极端干期长度的基本时空分布特征;对资料标准化后进行经验正交展开（EOF）和旋转经验正交展开（REOF）,研究其异常的空间结构及时间演变规律;并利用小波分析方法,分析了极端干期的周期性及突变的时间。结果表明：西北地区极端干期长度的气候平均分布与海拔高度及地理位置有较大的关系。西北地区极端干期长度异常在空间上主要表现为整体一致型,其次表现为东西相反的变化趋势。旋转载荷向量场（RLV）反映出极端干期长度的5个异常气候区：高原东北区,南疆区,青海区,北疆区和西北东南区。5个异常区极端干期长度均存在较明显的2~3 a高频振荡;其次西北东南区存在明显的16 a低频变化周期,而其他各区存在明显的8~11 a低频变化周期。新疆及青藏高原20世纪80年代后极端干期有缩短之趋势。高原东北区,青海区,北疆区的极端干期长度的分布有两个突变点;南疆区、西北东南区则各有一突变点。     

1951-2010 年中国气温变化分区及其区域特征

以中国623 个测站1951-2010 年逐日气温观测资料为基础数据, 通过正交旋转因子分析对1951-1980、1961-1990、1971-2000、1981-2010 年4 个时间段的年、冬、夏半年气温变化特征进行分区, 并探讨分区结果的季节和年代际差异。结果表明:依据年、夏半年气温变化特征, 可将全国划分成8 个不同的区域, 且研究时段内年、夏半年气温变化的空间结构比较稳定;而依据冬半年气温变化特征, 可将全国划分为7 个变化区, 且冬半年气温每30 年分区结果存在着明显变化。另外, 通过对区域平均气温距平序列的变化趋势分析可以得出:1951-2010 年间, 中国各区域气温均呈上升趋势, 升温趋势最快的是东北区(0.30 ℃∕10a), 最慢的是华南区(0.13 ℃∕10a);各区域升温过程不同步, 东北区与滇藏高原区显著增暖趋势在1961-1990 年开始出现, 而其他区域则发生在1971-2000 年及1981-2010 年。     

Spatio-temporal analysis of land-use conversion in the eastern coastal China during 1996–2005

Based on the acquaintance of the regional background of urban-rural transforma-tional development and investigations on the spot, this paper discusses the holistic situation, dominant factors and mechanism of arable land loss and land for construction occupation in the coastal area of China over the last decade, with the aid of GIS technology. Conclusions of the research are summarized as follows: (1) the arable land had been continuously de-creasing from 1996 to 2005, with a loss of 1,708,700 hm2 and an average decrement of 170,900 hm2 per year; (2) land for construction increased 1,373,700 hm2, with an average increment of 153,200 hm2 per year; (3) total area of encroachment on arable land for con-struction between 1996 and 2005 was 1,053,100 hm2, accounting for 34.03% of the arable land loss in the same period, the percentages of which used for industrial land (INL), trans-portation land (TRL), rural construction land (RUL) and town construction land (TOL) are 45.03%, 15.8%, 15.47% and 11.5%, respectively; and (4) the fluctuation of the increase of construction land and encroachment on arable land in the area were deeply influenced by the nation’s macroscopic land-use policies and development level of regional economy. The growth of population and advancement of technology promoted the rapid industrialization, construction of transportation infrastructures, rural urbanization and expansion of rural set-tlements in the eastern coastal area, and therefore were the primary driving forces of land-use conversion.     

Estimation and analysis of the ratio of transpiration to evapotranspiration in forest ecosystems along the North-South Transect of East China

Journal of Geographical Sciences - The ratio of transpiration to evapotranspiration (T/ET) is a key parameter for quantifying water use efficiency of ecosystems and understanding the interaction...     

综合湿度和温度影响的中国未来热浪预估

地面空气湿度直接影响人体驱散热负荷的效率,持续高温高湿天气将会严重影响人体健康。基于综合考虑温度和湿度协同作用的热胁迫指数——湿球黑球温度(WBGT)指数定义热浪,利用参考时期(1986—2005年)中国824个气象站点逐日平均气温和逐日相对湿度资料以及CMIP5多模式相应模拟数据,论文定量描述了未来时期(2076—2095年)不同排放情景下(RCP2.6、RCP4.5和RCP8.5)中国大陆地区可能遭遇的热浪事件的空间分布特征及其变化。研究结果表明：① 最有效的减排情景(RCP2.6)和高排放情景(RCP8.5)下中国大陆地区的平均热浪日数分别是参考时期的3.4倍和6.6倍,平均热浪强度(一年内所有热浪事件中日平均WBGT指数的最大值)也相对升高了1.6 ℃和4.9 ℃,未来时期RCP8.5情景下中国东部和南部地区的最高年均热浪强度甚至将达到40 ℃;② 虽然青藏高原地区的热浪强度等级低,但是未来时期热浪日数的增加幅度较为显著;③ 华南、长江中下游以及少数西南地区是综合考虑气温和湿度协同作用对人体热舒适的影响下,未来时期可能发生热浪最严重的地区,如果不考虑湿度要素的影响,那么将极有可能低估热浪在中国华南和东部等湿度较高地区的强度和影响。