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1.
简要介绍了浙江省气象科学研究所自行设计和研制的NOAA-AVHRR卫星资料处理业务系统的设计思路、总体结构及主要技术特点,重点介绍了系统软件中三维立体图像显示技术及其在植被生态环境监测中的应用.  相似文献   

2.
利用阿岱至赛尔龙公路(简称阿赛公路)沿线4个气象台站(尖扎、同仁、泽库、河南)1971—2000年30年气象资料,分析了沿线天气气候分布特征;另外,统计分析了1990—2009年气象环境对阿赛公路交通的影响,总结出交通事故的时空分布特征。  相似文献   

3.
利用南岭生态气象中心国家气象观测站和仁化县各乡镇自动站气象资料以及MODIS卫星遥感资料,分析了仁化近5年生态气象特征,结果表明:近5年仁化县年平均气温较常年平均偏高,降雨量在正常范围内波动,时空分布不均,日照较常年偏少,大气扩散条件整体良好、空气质量基本维持,植被覆盖结构呈现以高覆盖度为主体、中覆盖度区域随经济发展用地变化略有浮动的结构特征,植被覆盖度结构整体均衡,陆表生态环境维持良好。  相似文献   

4.
京沪沿线强降水频率及大风频率分布特征   总被引:6,自引:3,他引:6       下载免费PDF全文
文章利用京沪铁路沿线气象站的降水量和风速资料,统计分析了京沪铁路沿线各站严重影响高速列车行驶安全的两大气象因子——强降水和大风的分布特征,并给出了多年一遇的时雨量和多年一遇的日极大风速值,为京沪高速铁路设计提供科学的气象参数。  相似文献   

5.
对锡林郭勒草原退化的研究表明,除了人为干扰因素外,气象灾害也是造成草原退化的重要因素,研究气象灾害及其发生规律与草原退化的关系,对遏制和御防草原生态系统退化,防灾减灾,恢复草原原生植被有着重要意义,利用1953—2005年气象资料和2002—2005年生态气候监测资料,采用气候相似分区计算和分析干旱发生规律及演变趋势;对沙尘暴的发生强度和分布规律也做了深入研究。由于气象灾害日趋加重,草地植被不断退化,气象灾害与草原退化相互间的影响越来越大,气象灾害加速了草原退化进程,而草原退化使自然灾害更加频繁,造成的损失更加严重。治理草原生态环境,御防和减少气象灾害,是草原生态系统可持续发展的迫切需要。  相似文献   

6.
选用1982—2003年GIMMSNDVI数据集和陕西气温、降水、相对湿度资料,分析全省植被指数变化特征及其与气候因子相关性,揭示陕西植被对全球变暖的响应。结果表明:1982—2003年陕西植被覆盖总体缓慢增加,幅度为0.002/10 a,春季明显上升。陕北长城沿线及延安北部植被覆盖显著增加;关中部分地区植被由低覆盖度转为中覆盖度;秦岭东部、陕南巴山地区植被由中覆盖度转为高覆盖度;安康盆地高覆盖度植被显著增加。气温、降水和相对湿度均对植被有影响,并存在滞后效应,气温升高和相对湿度增大是植被生长期提前和延长的主要影响因素。  相似文献   

7.
内蒙古东北部冻土分布与地温关系   总被引:9,自引:0,他引:9  
利用 30 1国道沿线气象台站多年气象资料及交通部门的实验数据 ,对内蒙古东北部冻土进行了现状评述及演化趋势推断 。  相似文献   

8.
分析研究了欧亚大陆桥(中国段)沿线的气候特征与地理环境,影响和阻碍铁路运输的气象灾害;作了气象灾害区段划分,并提出铁路安全运输的气象保障与服务。  相似文献   

9.
气象卫星遥感监测甘肃河西绿洲植被变化   总被引:9,自引:0,他引:9  
根据甘肃降水资料和农业气象资料分析得出 ,1 989和 1 998年为相似年景 ,利用 1 989年和 1 998年NOAA气象卫星AVHRR资料 ,计算分析了 1 0a来河西绿洲植被面积和植被指数等级的变化。分析结果表明 ,1 0a来河西绿洲面积呈增加趋势 ,各绿洲植被指数有不同程度的增加。  相似文献   

10.
资料通讯   总被引:1,自引:0,他引:1  
资料通讯国家自然科学基金委员会地球科学部南京气象学院大气资料服务中心第4卷第2期(总第11期)1998年3月NCEP/NCAR40年再分析资料介绍美国气象环境预报中心(NCEP,其前身为美国国家气象中心NMC)和美国国家大气研究中心(NCAR)自19...  相似文献   

11.
The temporal variations during 1948-2010 and vertical structures of the summer Somali and Australia cross-equatorial flows(CEFs) and the implications for the Asian summer monsoon were explored in this study.The strongest southerly and northerly CEFs exist at 925 hPa and 150 hPa level,respectively.The low-level Somali(LLS) CEFs were significantly connected with the rainfall in most regions of India(especially the monsoon regions),except in a small area in southwest India.In comparison to the climatology,the lowlevel Australia(LLA) CEFs exhibited stronger variations at interannual time scale and are more closely connected to the East Asian summer monsoon circulation than to the LLS CEFs.The East Asian summer monsoon circulation anomalies related to stronger LLA CEFs were associated with less water vapor content and less rainfall in the region between the middle Yellow River and Yangtze River and with more water vapor and more rainfall in southern China.The sea-surface temperature anomalies east of Australia related to summer LLA CEFs emerge in spring and persist into summer,with implications for the seasonal prediction of summer rainfall in East Asia.The connection between the LLA CEFs and East Asian summer monsoon rainfall may be partly due to its linkage with El Nino-Southern Oscillation.In addition,both the LLA and LLS CEFs exhibited interdecadal shifts in the late 1970s and the late 1990s,consistent with the phase shifts of Pacific Decadal Oscillation(PDO).  相似文献   

12.
多年冻土区与季节冻土区地表反照率对比观测研究   总被引:3,自引:0,他引:3  
利用多年冻土区唐古拉气象站与季节冻土区那曲毕节气象站2008年辐射、土壤未冻水含量及积雪等数据,对两种冻土类型下垫面上的地表反照率进行分析研究,得出两站地表反照率均呈现冬春季较大,夏秋季较小的规律,并且,积雪使地表反照率形成极大值,最大极值接近0.9。唐古拉站的地表反照率整体上比毕节站大,年平均地表反照率分别为0.38和0.31。地表反照率月较差(每月日平均地表反照率最大值与最小值的差值)冬季毕节站高于唐古拉站,而夏秋季节则相反。晴天,两站地表反照率均呈现"U"形,表现出早晚大、中午小,春、夏、秋、冬各季节典型晴天的地表反照率日平均值唐古拉站分别为0.23、0.20、0.20和0.25,毕节站为0.26、0.21、0.22和0.29。此外,讨论了两站太阳高度角和土壤湿度对地表反照率的影响,得出两站地表反照率随太阳高度角的增大均呈现e指数衰减趋势,土壤湿度与地表反照率呈负相关关系,且降雨对地表反照率的变化影响较大。  相似文献   

13.
肉类屠宰加工行业在其生产过程中主要有废水、废气、废渣产生,对周围环境的地表水、地下水和大气会产生不利影响。针对其污染物产生的特点,分析了污染物对环境的影响并提出了防治对策。  相似文献   

14.
Summary Atmospheric variability in outgoing long-wave radiation (OLR) and tropospheric relative vorticity (VOR) over the South American region was studied from 1979 to 1996 using the complex Morlet wavelet function. The analyses focus on spatial variation in intraseasonal and submonthly scales. Scalograms were used to measure submonthly intraseasonal oscillations in convection, which were found to be predominant in the tropical regions. However, 7-day and 15-day oscillations were observed at tropical and extratropical latitudes in spring and winter, indicating that transient disturbances play a more prominent role. Regarding VOR, tropical energy intensities were highest in the spring and summer, whereas subtropical and extratropical energy intensities were highest in the autumn and winter. The dynamics of the 25-day and 45-day VOR oscillations indicates a possible correlation with Rossby waves over the eastern tropical Pacific Ocean, mainly during the summer. During winter, the 7-day and 15-day VOR oscillations are more frequent at higher latitudes and are enhanced along storm tracks. It was also observed that convection amplitudes in the regions of maximum intensity change appreciably from year to year and from season to season, showing that the behavior of the submonthly and intraseasonal oscillations is nonperiodic and correlates strongly with El Ni?o/Southern Oscillation years. These results confirm the efficiency of wavelet analysis for time-scale studies of atmospheric variability.  相似文献   

15.
Summary Circulation types were identified by means of zonal and meridional indices calculated separately over ten different regions of 20° × 20° over the Mediterranean and Europe. Seasonal and annual rainfall totals in four stations Lisbon, Luqa (Malta), Athens and Jerusalem, were compared with circulation types for the period 1873–1991. Correlation coefficients of circulation indices with precipitation, for each station in each season were calculated and mapped.An oscillation in the meridional index during the winter and the spring, between the western and eastern Mediterranean, was detected.Time series analysis of the circulation indices demonstrates a significant reduction in zonality and an increase in meridionality mainly in spring and in summer, over most of the study area.With 9 Figures  相似文献   

16.
The data-collection campaign for the 2008 International Polar Year–Circumpolar Flaw Lead System Study saw the Canadian Coast Guard Ship (CCGS) Amundsen, a research icebreaker, overwinter in high-concentration unconsolidated sea ice in Amundsen Gulf. Environmental monitoring continued into the open-water season. During this period, the Amundsen registered five relatively deep mean sea-level pressure minima (less than 100?kPa). Three were selected for further analysis based on season and the nature of the underlying ocean or sea-ice surface: (1) a winter pressure minimum over unconsolidated sea ice, (2) a spring pressure minimum which likely contributed to the break-up of the sea-ice cover on Amundsen Gulf, and (3) a summer pressure minimum over open water. The characteristics of these pressure minima and the impact of their passage on the atmospheric boundary layer and on the sea-ice cover as they crossed Amundsen Gulf were examined. Several features were revealed by the analysis. (1) The winter and summer pressure minima were migratory cyclones accompanied by Arctic frontal waves with characteristics very similar to the polar frontal waves associated with the migratory cyclones found at more southerly latitudes, whereas the spring pressure minimum was attributed to an Arctic frontal trough of low pressure with the cyclonic centre remaining south of the Gulf. (2) The passage of the frontal-wave cyclone in winter and the frontal trough of low pressure in spring disrupted the equilibrium that had been established during more settled periods between the atmospheric boundary layer and the mosaic surface (leads, polynyas, and sea ice); however, equilibrium was quickly re-established. (3) In summer, the thermal structure of the lower atmospheric boundary layer persisted through the passage of the frontal-wave cyclone over the open-water surface. (4) The passage of the frontal-wave cyclone in winter and the frontal trough of low pressure in spring modified the mesoscale sea-icescape.  相似文献   

17.
温室效应及其对气候影响的最新研究   总被引:5,自引:0,他引:5  
王绍武 《气象》1990,16(10):3-9
  相似文献   

18.
Understanding variations in precipitation from a variety of aspects is important for the utilization of water resources. Based on daily precipitation records at 98 meteorological stations in Sichuan province, southwestern China, the spatial and temporal changes in wet/dry spells were investigated by using 14 precipitation indices. The Mann–Kendall trend test is used to detect trends in the index series. Results suggest that the decrease of precipitation in central and eastern Sichuan was significant in terms of decreasing tendencies of wet spell indices. However, the decreasing trend of dry spell indices suggested an increase in precipitation in western Sichuan province. A higher risk of droughts can be expected in autumn and wet spell indices in winter and spring are increasing, implying obvious seasonality and seasonal shifts of change in precipitation within this province. Wet/dry spells with short duration were accounted for a large proportion of spells in Sichuan. The occurrence and fractional contribution of short-duration wet spells were increasing. The same trend was found in dry spells with short and moderate duration in Sichuan  相似文献   

19.
黄土高原塬区地表辐射和热量平衡观测与分析   总被引:13,自引:11,他引:13  
利用2005年夏季黄土高原塬区陆面过程野外试验(LOPEX05)的观测资料,初步分析了甘肃平凉黄土高原塬区地表辐射收支和热量平衡特征。结果显示,黄土高原塬区地面长波辐射大于大气长波辐射,典型晴天、阴天和雨天情况下两者平均差值分别为65,25和8 W.m-2;对于地气能量交换各个分量而言,黄土高原塬上和塬下在相同下垫面下的差别不大,但裸地和有植被的下垫面差别很明显;在白天,潜热在净辐射中所占的比重较大,其次是感热,最后是土壤热通量。对能量平衡中的储存项如热通量板上层土壤的热存储和植被冠层存储进行了估算,结果表明,土壤的热储存项在-30~70W.m-2之间,而植被的热能储存项在-10~25 W.m-2之间。在考虑估算的存储项之后,能量平衡散布图斜率由0.68提高到0.79,相关系数R由0.90提高到0.93,两者分别提高了11.0%和3.0%,并对能量不平衡有明显的改进,说明能量储存项在地表能量闭合中必须考虑。  相似文献   

20.
漠河地区臭氧的观测和计算   总被引:2,自引:0,他引:2  
1997年3月上旬,在黑龙江漠河地区对地面和整层臭氧、太阳辐射等进行了短期观测,以初步了解该地区臭氧和辐射的变化规律以及它们之间的相互关系.研究发现,漠河地区近地面臭氧日变化明显,其峰值出现在每日10:00(北京时间)左右,并早于紫外辐射(UV)峰值出现时间.整层大气臭氧总量的日变化特征不明显.基于UV能量守恒,建立了臭氧与其影响因子-光化学、散射、UV等因子之间较好的定量关系和经验模式,并将其用于计算地面、整层大气臭氧小时值和日平均值.结果表明,计算值与观测值吻合的都比较好,它们相对偏差的平均值分别为:地面臭氧小时值(11.9%)和日平均值(9.0%);整层大气臭氧小时值和日平均值-7.4%、1.8%.因此,地面和整层臭氧的经验算法是合理和可行的.利用散射辐射/直接辐射(D/S)和散射辐射/总辐射(D/Q)可以描述大气中的物质如气溶胶、云等的散射作用.采用D/Q表示散射作用可以提高地面臭氧和整层大气臭氧计算的准确度,特别是对云量较大的情况.    相似文献   

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