成都平原中西部近40年气候特征及其变化研究

利用成都平原中西部5个气象观测站的降水、温度和日照资料,分析了成都平原中西部降水、温度和日照的分布规律、气候特征及其变化,得出以上地区年平均气温存在准4年的振动周期;1990年以来大部分地区存在降水减少,气温升高,日照减少的现象.     

近37年南充市雷暴的气候特征分析

利用南充市7个站点1971-2007年的雷暴观测资料,通过数理统计分析和初终日期的保汪率计算,分析了南充市雷暴的气候变化特征.结果显示:近37年南充市雷暴日数总体呈减少的趋势,每10年雷暴日数减少约3.5天,但全市年雷暴日数仍较多,年平均为31.9天,除1月无雷暴发生外,其余11个月均有雷暴发生,4-9月雷暴日数占全年的93.8%,其中7-8月占53.1%,属于强雷季节.在80%的保证率条件下,初终间日数达237天.     

近47年白银市气候变化及其对农业生产的影响分析

利用白银市4个代表站逐日平均气温、逐日地面最低温度，分别得到≥0℃初终日期、初终霜冻日期以及利用逐月平均气温、平均最高气温、平均最低气温和逐月降水资料，对白银市近47a的气候变化特征进行分析，同时分析了气候变化对农业生产的影响，为充分利用变化了的农业气候资源，减少不利因素带来的影响提出了对策和建议。     

Climate change and glacier area variations in China during the past half century

Glacier variations in the Tibetan Plateau and surrounding mountain ranges in China affect the livelihood of over one billion people who depend on water from the Yellow, Yangtze, Brahmaputra, Ganges and Indus rivers originating in these areas. Based on the results of the present study and published literature, we found that the glaciers shrank 15.7% in area from 1963 to 2010 with an annual area change of -0.33%. The shrinkage generally decreased from peripheral mountain ranges to the interior of Tibet.The linear trends of annual air temperature and precipitation at 147 stations were 0.36°C(10a)~(-1) and 8.96 mm(10a)~(-1) respectively from 1961 to 2010. The shrinkage of glaciers was well correlated with the rising temperature and the spatial patterns of the shrinkage were influenced by other factors superimposed on the rising temperature such as glacier size, type, elevation, debris cover and precipitation.     

Seasonal change of steric sea level in the GIN seas

The Greenland Sea,Iceland Sea,and Norwegian Sea (GIN seas) form the main channel connecting the Arctic Ocean with other Oceans,where significant water and energy exchange take place,and play an important role in global climate change.In this study steric sea level,associated with temperature and salinity,in the GIN seas is examined based on analysis of the monthly temperature and salinity fields from Polar science center Hydrographic Climatology (PHC3.0).A method proposed by Tabata et al.is used to calculate steric sea level,in which,steric sea level change due to thermal expansion and haline contraction is termed as the thermosteric component (TC) and the halosteric component (SC),recpectively.Total steric sea level (TSSL) change is the sum of TC and SC.The study shows that SC is making more contributions than TC to the seasonal change of TSSL in the Greenland Sea,whereas TC contributes more in the Norwegian and the Iceland Seas.Annual variation of TSSL is larger than 50 mm over most regions of the GIN Seas,and can be larger than 200 mm at some locations such as 308 mm at 76.5 N,12.5 E and 246 mm at 77.5 N,17.5 W.     

CHARACTERISTICS OF CHANGE IN TEMPERATURE DURING THE PAST 50 YEARS IN JILIN PROVINCE OF CHINA

Based on the monthly mean temperature, the changing processes and tendencies of temperature during1951 -2000 in Jilin Province, which is in Northeast China, are analyzed. And the spatial characteristics of the changeare submitted. In the past 50 years the temperature of Jilin Province was increasing just like the other areas in the world.Since 1990, the increasing of temperature has been more obvious than that in the previous 40a. From the west to theeast, the province has larger temperature rising. According to Principal Component Analysis (PCA) of temperature field,Jilin Province is divided into 3 regions and the degree of becoming warmer is different from region to region. During theperiod of 1951 to 2000, the annual temperature in Jilin Province has been rising, so has the temperature in winter andsummer. The average temperature in the 1990s was 0. 5 - 2. 0℃ higher than that in the 1950s. From the west to theeast, the increasing of temperature became smaller.     

四川省农业生态环境问题与对策

四川地处长江中上游地区，是全国三大林区之一和生态保护与建设的重点区域。搞好四川农业生态环境建设，对全国的生态保护与建设和长江中下游地区的经济发展有着十分重要的作用。该文全面分析评价了四川省农业生态环境的主要问题和演变趋势，提出了四川省农业生态环境恢复与重建的对策措施。     

Effect of landform on seasonal temperature structures across China in the past 52 years

Introduction The temperature in the Northern Hemisphere increased by 0.4℃ between the 1960s and the 1980s, and in the same period the temperature of the Tibetan Plateau increased by 0.5℃ (IPCC 2001). The temperature in China increased by 0.3 ℃ between 1951 and 1990 (DING and DAI 1994). Using 15 different general circulation models, Jones and Moberg (2003) estimated that the rate of annual warming over the continents between 1901 and 2000 was 0.078℃ decade–1 (significant at the 99.9…     

Sediment records of environmental changes in the south end of the Zhejiang-Fujian coastal mud area during the past 100 years

Previous studies carried out in the East China Sea （ECS） mud area focused on long-term environmental changes in sedimentary records during the Holoeene, especially during the mid-Holocene high-stand water levels period. These results indicate that sensitive grain size groups can be used as a sedimentary proxy to reconstruct the evolution of the East Asian Winter Monsoon （EAWM）. The studies have been carried out mainly in the northern and middle portions of the Zhejiang-Fujian coastal mud, however, similar research in the southern portion and the comparison between sedimentary proxy and modern measured data of EAWM are lacking. In this paper, we focused on a sedimentary record of the past 100 years with an enhanced resolution of 1.8 years. Investigations of the southern end of the Zhejiang-Fujian coastal mud area were conducted on the basis of 21~Pb chronology, grain-size analysis and chemical element analysis. The correspondence between the mean grain size （Mz） of sediment sensitive grain size and the measured EAWM was confirmed for the first time. We found that during the recent 100 years, the variation of the mean grain size of the sensitive population in the southern portion of the Zhejiang-Fujian mud was mainly controlled by the EAWM intensity changes; and not directly related to changes in the sediment discharge from Datong station of the Changjiang River （DTSD）. Finally, recent changes in the content of heavy metals in study area reflect the impact of human activities on the environment.     

甘肃省近35年连阴雨天气气候特征分析

利用1967～2001年甘肃省80个气象站的逐日降水资料对连阴雨特征进行了较全面的分析.结果表明：甘肃省连阴雨分布的特点是自西北向东南呈台阶状增加,连阴雨相对比较多的地区为甘南地区、陇南东部和陇东东部地区,在甘肃中部-天水-武都一带相对形成一个南北向的少连阴雨带.区域性连阴雨过程的月、季特征表明,夏季区域性连阴雨过程最多,秋季次之,春季和冬季最少.年代际变化特征表明春季区域性连阴雨次数从20世纪70年代到90年代变化不大,但夏秋季连阴雨次数,70年代明显偏多,80年代之后总体次数减少幅度较大.最后从不同季节形成的连阴雨环流形式进行了分析.