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81.
82.
利用全市21个自动气象站的逐时资料,分析了台风“麦莎”对苏州市的风雨影响,并将其与20世纪90年代以来对苏州造成严重影响的9015号和9711号两个台风,分别从登陆时强度、登陆后移动路径、影响苏州市的持续时间和形成的风雨实况等方面进行了对比分析。通过分析比较得出,台风“麦莎”是20世纪90年代以来对苏州影响最严重的一次台风过程。 相似文献
83.
84.
2011年初夏我国长江中下游降水的气候特征及成因 总被引:6,自引:3,他引:3
文章主要分析了2011年初夏长江中下游降水的气候特征及其成因。结果表明:2011年5月长江中下游降水异常偏少,6月转为异常偏多,出现了明显的旱涝转换。长江中下游地区的旱涝转换主要受南海季风、东亚季风强度以及西太平洋副热带高压(副高)的异常快速北跳的影响。研究还发现,6月亚洲中高纬长期维持两槽一脊的环流形势,东北冷涡活动频繁,多次引导冷空气南下。同时,副高异常偏北、偏西,并出现多次西伸过程。由于冷涡的加强南压与西伸的副高相互作用,促使长江以南地区西南气流明显增强,使得冷暖空气在长江中下游地区交汇,最终导致该地降水偏多。 相似文献
85.
2011年全球重大天气气候事件及其成因 总被引:2,自引:0,他引:2
2011年,全球气温偏高,为有观测记录以来的第十个暖年,是近60年来出现拉尼娜事件的年份中全球气温最高的一年。2011年,全球热带气旋活动较常年偏少。4月,一次拉尼娜事件结束,9月又一次拉尼娜事件生成。年初,低温、寒流席卷亚洲大部,暴风雪频繁袭击北美地区。西欧和中国东部出现严重春旱。夏季,非洲东部经历了20世纪80年代以来最严重的干旱,而东南亚、巴基斯坦和中南美洲洪涝灾害严重。全球极端偏暖事件主要出现在欧洲西部和西北部、南亚南部、东亚中西部、北美东南部等地;极端偏冷事件主要出现在东亚、澳大利亚、非洲南部和美国东北部和西部等地。而南美中东部、东南亚及中国东南部、日本、澳大利亚北部、非洲西部等地出现了极端强降水事件。研究发现,2010/2011年拉尼娜事件和台风活动是导致东南亚洪涝出现的重要原因,而巴基斯坦洪涝主要与印度洋正位相偶极型海温分布有关。 相似文献
86.
S. S. Andreev 《Russian Meteorology and Hydrology》2009,34(8):556-560
Bioclimatic conditions of the Southern Federal Okrug that characterize how comfort the climate conditions are for the human
organism are studied. The territory is regionalized based on the estimated values of the pathogenicity index I and coefficient of the atmosphere self-purification potential K
p
. 相似文献
87.
Yu. A. Izrael V. M. Zakharov N. N. Petrov A. G. Ryaboshapko V. N. Ivanov A. V. Savchenko Yu. V. Andreev V. G. Eran’kov Yu. A. Puzov B. G. Danilyan V. P. Kulyapin V. A. Gulevskii 《Russian Meteorology and Hydrology》2009,34(10):635-638
The paper describes the results of the field experiment on studying solar radiation transmission in the visible wavelength range through model aerosol media formed in the lower troposphere with the help of generators installed aboard helicopters. The refractive index and the average size of the aerosol particles formed are close to those characteristic of the natural stratospheric aerosol. The composition of the equipment complex used to control aerosol optical and microphysical aerosol parameters is considered. The measurement results are in satisfactory agreement with the results of theoretical and experimental studies in simulation chambers. 相似文献
88.
2005年6月华南暴雨期间西太平洋副高西伸过程分析 总被引:7,自引:1,他引:6
利用NCEP/NCARⅡ逐日再分析资料以及我国实测的降水资料,对2005年6月华南暴雨期间西太平洋副高的西伸过程进行了分析.结果表明:副高的东西进退可能与暴雨过程存在某种联系.分析指出副高中心的下沉气流主要是由副高南北两侧雨带中凝结潜热释放效应所致的上升气流在高空下沉而产生的,副高中心垂直运动的出现有利于副高的加强.而副高南北两侧雨带不但可以加强副高,同时又会激发正涡度增长,限制副高在南北方向上的活动,此时西侧印度季风雨带则会在副高西侧激发反气旋性涡度发展,即可诱使副高西伸.因此,华南强降水和印度季风区降水的共同作用使得副高加强西伸. 相似文献
89.
Natalia Rudaya Pavel Tarasov Nadezhda Dorofeyuk Nadia Solovieva Ivan Kalugin Andrei Andreev Andrei Daryin Bernhard Diekmann Frank Riedel Narantsetseg Tserendash Mayke Wagner 《Quaternary Science Reviews》2009,28(5-6):540-554
This study presents the results of the palynological and diatom analyses of the sediment core recovered in Hoton-Nur Lake (48°37′18″N, 88°20′45″E, 2083 m) in 2004. Quantitative reconstruction of the Holocene vegetation and climate dynamics in the semiarid Mongolian Altai suggests that boreal woodland replaced the primarily open landscape of northwestern Mongolia at about 10 kyr BP (1 kyr = 1000 cal yr) in response to a noticeable increase in precipitation from 200–250 mm/yr to 450–550 mm/yr. A decline of the forest vegetation and a return to a predominance of open vegetation types occurred after 5 kyr BP when precipitation sums decreased to 250–300 mm/yr. Prior to 11.5 kyr BP diatom concentrations are relatively low and the lake is dominated by planktonic Cyclotella and small Fragilariaceae, suggesting the existence of a relatively deep and oligotrophic/mesotrophic lake. The great abundance of Staurosirella pinnata from the beginning of the record until 10.7 kyr BP might imply intensified erosion processes in the catchment and this is fully consistent with the presence of scarce and dry vegetation and the generally arid climate during this period. From about 10.7 kyr BP, more planktonic diatom taxa appeared and increased in abundance, indicating that the lake became more productive as diatom concentration increased. This change correlates well with the development of boreal woodland in the catchment. Decrease in precipitation and changes in the vegetation towards steppe are reflected by the rapid increase in Aulacoseira distans from about 5 kyr BP. The Holocene pollen and diatom records do not indicate soil and vegetation cover disturbances by the anthropogenic activities, implying that the main transformations of the regional vegetation occurred as a result of the natural climate change. Our reconstruction is in agreement with the paleomonsoon records from China, demonstrating an abrupt strengthening of the summer monsoon at 12 kyr BP and an associated increase in precipitation and in lake levels between 11 and 8 kyr BP, followed by the stepwise attenuation of the monsoon circulation and climate aridization towards the modern level. The records from the neighboring areas of Kazakhstan and Russia, situated west and north of Hoton-Nur, demonstrate spatially and temporally different Holocene vegetation and climate histories, indicating that the Altai Mountains as a climate boundary are of pivotal importance for the Holocene environmental and, possibly, habitation history of Central Asia. 相似文献
90.
A. V. Ivanova V. L. Afanasiev P. P. Korsun A. R. Baranskii M. V. Andreev V. A. Ponomarenko 《Solar System Research》2012,46(4):313-319
The results of the photometric observations of comet 29P/Schwassmann-Wachmann 1 are analyzed. The comet demonstrates substantial activity at heliocentric distances larger than 5 AU, i.e., outside the water ice sublimation zone. The CCD images of the comet were obtained in wideband R filters at the 6-meter telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS) and at the 2-meter Zeiss-2000 telescope of the Peak Terskol Observatory. The processing of the images with special digital filters allowed the active structures (jets) to be distinguished in the dust coma of the comet. With the cross-correlation method, the rotation period of the cometary nucleus was determined as 12.1 ± 1.2 and 11.7 ± 1.5 days for the observations taken in December 2008, and February 2009, respectively. The probable causes of the difference in the estimates of the rotation period of the cometary nucleus obtained by different authors are discussed. 相似文献