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1.
周恩来总理是我国第一代革命领导核心成员之一,他协助毛泽东主席在极其艰难的环境下领导我国的革命斗争,坚持抗日战争和解放战争,夺取了全国革命的伟大胜利,创建了中华人民共和国。新中国成立后,他担任了26年的总理,亲自指挥我国各条战线的建设,并在国际上开展积极的外交斗争和活动,被公认为世界上的一代伟人。  相似文献   

2.
运用遥感图像处理系统(ENVI)对快鸟(Quickbird)高分辨率遥感影像进行预处理,利用归一化差值植被指数(NDVI)、归一化差异绿度指数(NDGI)、土壤调节植被指数(SAVI)和修正土壤调节植被指数(MSAVI)对南京市鼓楼区进行了绿地信息提取,通过Matlab软件比较了其灰度图像、直方图和二值图像,并分析其方差,在C语言的平台上进行了精度评定.实验结果表明:在该研究区中,SAVI、NDVI的绿地提取能力较好;NDGI、MSAVI出现了明显的漏分、错分情况,但MSAVI在建筑物、植被边缘提取上表现出相对的优越性.  相似文献   

3.
从卫星云图的区别,常见的云型,重要天气系统云型的特征以及对降水的作用等方面进行分析。  相似文献   

4.
依据气象业务需求,以SQLServer、ArcSDE为数据库依托,以Delphi为开发工具,以Arc GISEngine Development Kit 9.2为开发平台设计并实现了基于GIS的自动气象站数据系统。在对自动气象站数据自动采集、规范管理和质量检查的基础上,实现了气象要素的多条件灵活查询、异常天气条件的监测...  相似文献   

5.
通过对GSM短信方式的自动气象站运行与维护情况进行分析,提出保障自动气象站安全运行的维护对策。  相似文献   

6.
南京的天气     
竺可桢  薛铁虎 《气象学报》1936,12(4):201-206
天气这个问题是人们三句不离口的东西,而也是人们最难了解的东西。这种只会谈而不能了解的现象,中外皆然。的确!在中国拿天气作为谈话的资料,已经谚语化了。你瞧!中国“谈话”俗语叫“谈天”,他的意思就是闲谈天气;中国“问安”或“致意”是叫“寒暄”,意思是问问“冷热”或谈谈“天气的状况是否适宜於对方的起居”。  相似文献   

7.
对康熙帝风的性能认识的分析   总被引:1,自引:0,他引:1  
康熙帝对风的认识,有独到的见解。他关于山东与京师风向之异的观测,近几十年常被误认为他有风场不连续的概念之证。本文分析原文,指出这种看法的错误。又举出风对成盐及形成沙漠白龙堆沙丘的作用两例,分析康熙帝在这两个问题上认识的局限性。  相似文献   

8.
FTP服务器的建立及客户端的使用   总被引:1,自引:0,他引:1  
王婉  姚博  周鸣 《河南气象》2006,(1):75-76
利用FTP文件传输协议,使用Serv-U软件构建FTP服务器,使客户端用户能够通过互联网访问FTP服务器,进行信息资源的共享和传输。  相似文献   

9.
气候变化的影响阈值与中国的粮食安全   总被引:13,自引:3,他引:10       下载免费PDF全文
利用区域气候模式和作物模型,模拟了IPCC SRES A2和B2情景下未来中国粮食作物的单产变化,结合人口和经济发展,分析了气候变化对农业生产影响的温度阈值。结果表明:不考虑CO2的肥效,气候变化对农业生产影响的温度阈值可能在2.0~2.5℃左右;考虑CO2的肥效,农业生产不存在温度阈值。考虑了技术和贸易因素后,忽略CO2肥效,A2情景下的基本粮食安全有可能存在问题;考虑CO2的肥效后,气候变化不会影响到中国的粮食安全。  相似文献   

10.
从大气气溶胶的微物理结构出发,研究了气溶胶表层膜受大气相对湿度(Hr)的影响发生S(+4)氧化成为硫酸的过程,同时给出了不同湿度条件下污染大气中气溶胶粒子酸化作用的理论分析结果.研究分析表明,气溶胶颗粒表面的水份含量对于成功的氧化过程是一个必不可少的条件.由于周围环境大气相对湿度能够极大地改变气溶胶粒子的水份含量,因而,它也能对气溶胶粒子酸化作用的程度产生影响.研究发现,对于吸湿性气溶胶,在相同的条件下,Hr≤30%的干粒子和Hr≥70%的湿粒子都会经历不同程度的酸化.  相似文献   

11.
Using the International Comprehensive Ocean-Atmosphere Data Set(ICOADS) and ERA-Interim data, spatial distributions of air-sea temperature difference(ASTD) in the South China Sea(SCS) for the past 35 years are compared,and variations of spatial and temporal distributions of ASTD in this region are addressed using empirical orthogonal function decomposition and wavelet analysis methods. The results indicate that both ICOADS and ERA-Interim data can reflect actual distribution characteristics of ASTD in the SCS, but values of ASTD from the ERA-Interim data are smaller than those of the ICOADS data in the same region. In addition, the ASTD characteristics from the ERA-Interim data are not obvious inshore. A seesaw-type, north-south distribution of ASTD is dominant in the SCS; i.e., a positive peak in the south is associated with a negative peak in the north in November, and a negative peak in the south is accompanied by a positive peak in the north during April and May. Interannual ASTD variations in summer or autumn are decreasing. There is a seesaw-type distribution of ASTD between Beibu Bay and most of the SCS in summer, and the center of large values is in the Nansha Islands area in autumn. The ASTD in the SCS has a strong quasi-3a oscillation period in all seasons, and a quasi-11 a period in winter and spring. The ASTD is positively correlated with the Nio3.4 index in summer and autumn but negatively correlated in spring and winter.  相似文献   

12.
<正>The Taal Volcano in Luzon is one of the most active and dangerous volcanoes of the Philippines. A recent eruption occurred on 12 January 2020(Fig. 1a), and this volcano is still active with the occurrence of volcanic earthquakes. The eruption has become a deep concern worldwide, not only for its damage on local society, but also for potential hazardous consequences on the Earth’s climate and environment.  相似文献   

13.
The moving-window correlation analysis was applied to investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the synchronous autumn precipitation in Huaxi region, based on the daily precipitation, sea surface temperature (SST) and atmospheric circulation data from 1960 to 2012. The correlation curves of IOD and the early modulation of Huaxi region’s autumn precipitation indicated a mutational site appeared in the 1970s. During 1960 to 1979, when the IOD was in positive phase in autumn, the circulations changed from a “W” shape to an ”M” shape at 500 hPa in Asia middle-high latitude region. Cold flux got into the Sichuan province with Northwest flow, the positive anomaly of the water vapor flux transported from Western Pacific to Huaxi region strengthened, caused precipitation increase in east Huaxi region. During 1980 to 1999, when the IOD in autumn was positive phase, the atmospheric circulation presented a “W” shape at 500 hPa, the positive anomaly of the water vapor flux transported from Bay of Bengal to Huaxi region strengthened, caused precipitation ascend in west Huaxi region. In summary, the Indian Ocean changed from cold phase to warm phase since the 1970s, caused the instability of the inter-annual relationship between the IOD and the autumn rainfall in Huaxi region.  相似文献   

14.
The atmospheric and oceanic conditions before the onset of EP El Ni?o and CP El Ni?o in nearly 30 years are compared and analyzed by using 850 hPa wind, 20℃ isotherm depth, sea surface temperature and the Wheeler and Hendon index. The results are as follows: In the western equatorial Pacific, the occurrence of the anomalously strong westerly winds of the EP El Ni?o is earlier than that of the CP El Ni?o. Its intensity is far stronger than that of the CP El Ni?o. Two months before the El Ni?o, the anomaly westerly winds of the EP El Ni?o have extended to the eastern Pacific region, while the westerly wind anomaly of the CP El Ni?o can only extend to the west of the dateline three months before the El Ni?o and later stay there. Unlike the EP El Ni?o, the CP El Ni?o is always associated with easterly wind anomaly in the eastern equatorial Pacific before its onset. The thermocline depth anomaly of the EP El Ni?o can significantly move eastward and deepen. In addition, we also find that the evolution of thermocline is ahead of the development of the sea surface temperature for the EP El Ni?o. The strong MJO activity of the EP El Ni?o in the western and central Pacific is earlier than that of the CP El Ni?o. Measured by the standard deviation of the zonal wind square, the intensity of MJO activity of the EP El Ni?o is significantly greater than that of the CP El Ni?o before the onset of El Ni?o.  相似文献   

15.
Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 days) on insect migration. A case study was conducted to ascertain the influence of low-frequency atmospheric oscillation on the immigration of brown planthopper, Nilaparvata lugens(Stl), in Hunan and Jiangxi provinces. The results showed the following:(1) The number of immigrating N. lugens from April to June of 2007 through 2016 mainly exhibited a periodic oscillation of 10 to 20 days.(2) The 10-20 d low-frequency number of immigrating N. lugens was significantly correlated with a low-frequency wind field and a geopotential height field at 850 h Pa.(3) During the peak phase of immigration, southwest or south winds served as a driving force and carried N. lugens populations northward, and when in the back of the trough and the front of the ridge, the downward airflow created a favorable condition for N. lugens to land in the study area. In conclusion, the northward migration of N. lugens was influenced by a low-frequency atmospheric circulation based on the analysis of dynamics. This study was the first research connecting atmospheric low-frequency oscillation to insect migration.  相似文献   

16.
基于最新的GTAP8 (Global Trade Analysis Project)数据库,使用投入产出法,分析了2004年到2007年全球贸易变化下南北集团贸易隐含碳变化及对全球碳排放的影响。结果显示,随着发展中国家进出口规模扩张,全球贸易隐含碳流向的重心逐渐向发展中国家转移。2004年到2007年,发达国家高端设备制造业和服务业出口以及发展中国家资源、能源密集型行业及中低端制造业出口的趋势加强,该过程的生产转移导致全球碳排放增长4.15亿t,占研究时段全球贸易隐含碳增量的63%。未来发展中国家的出口隐含碳比重还将进一步提高。贸易变化带来的南北集团隐含碳流动变化对全球应对气候变化行动的影响日益突出,发达国家对此负有重要责任。  相似文献   

17.
正ERRATUM to: Atmospheric and Oceanic Science Letters, 4(2011), 124-130 On page 126 of the printed edition (Issue 2, Volume 4), Fig. 2 was a wrong figure because the contact author made mistake giving the wrong one. The corrected edition has been updated on our website. The editorial office is sincerely sorry for any  相似文献   

18.
19.
Index to Vol.31     
正AN Junling;see LI Ying et al.;(5),1221—1232AN Junling;see QU Yu et al.;(4),787-800AN Junling;see WANG Feng et al.;(6),1331-1342Ania POLOMSKA-HARLICK;see Jieshun ZHU et al.;(4),743-754Baek-Min KIM;see Seong-Joong KIM et al.;(4),863-878BAI Tao;see LI Gang et al.;(1),66-84BAO Qing;see YANG Jing et al.;(5),1147—1156BEI Naifang;  相似文献   

20.
正Journal of Meteorological Research is an international academic journal in atmospheric sciences edited and published by Acta Meteorologica Sinica Press,sponsored by the Chinese Meteorological Society.It has been acting as a bridge of academic exchange between Chinese and foreign meteorologists and aiming at introduction of the current advancements in atmospheric sciences in China.The journal columns include Articles.Note and Correspondence,and research letters.Contributions from all over the world are welcome.  相似文献   

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