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1.
利用NASA/CERES发布的2001~2015年云参数资料,选取高层云、雨层云、层积云的云水含量和云粒子有效半径,统计分析了西南地区云参数的时空分布特征和变化趋势。结果表明:从年均空间分布来看,西南地区液水和冰水含量均东部高于西部,海拔低的地区高于海拔高的地区;高层云和雨层云液相和冰相云粒子有效半径在川西高原最大。从数值大小来看,雨层云液水和冰水含量最多,分别介于90~230 g/m2和100~300 g/m2,层积云最少,分别介于0~80 g/m2和0~60 g/m2;冰相云粒子有效半径高于液相2~6 μm。从季节分布来看,雨层云液水和冰水含量秋季和冬季偏高,夏季和春季偏少,高层云和层积云季节差异较小;液相云粒子有效半径均夏季最大。从变化趋势来看,西南地区各地液水和冰水含量均呈减少趋势,液相和冰相云粒子有效半径有呈减少或增加趋势。  相似文献   

2.
利用NASA/CERES发布的L3级云资料,选取西南地区(云南、贵州、四川、重庆)2001~2010年水高层云、水雨层云、水层积云、水层云的云水含量数据,研究了该区域4种类型云的年和季节云水含量时空分布特征和变化趋势。结果表明:(1)4种类型云的年和季节云水含量均在海拔低的地方偏多,海拔高的地方偏少。重庆、贵州云水含量高于云南、四川;(2)水雨层云年和季节云水含量最大,其次为水层云和水高层云,水层积云云水含量最少;(3)近10 a来,整个西南地区4种类型云的年平均云水含量均呈递减趋势;(4)4种类型云的云水含量秋季高于春季;(5)春季,中云(水高层云、水雨层云)云水含量既有增加区域,也有减少区域,低云(水层积云、水层云)云水含量呈递减趋势;秋季,中云、低云云水含量均为递减趋势;水雨层云和水层云年和季节云水含量的递减趋势最显著。  相似文献   

3.
准确估算云量是了解青藏高原云参数时空特征的基础。通过相关分析、回归分析、趋势分析方法,分析了近21年来青藏高原云分布的动态变化。利用MODIS云量日产品(MOD08_D3)数据和ERA5再分析资料,分析了青藏高原不同阶段云量分布和云参数的时空特征。结果表明,高云区云量中心位于墨脱县(77.3%),林芝(72.5%)地区云量最大,青藏高原日平均云量在过去21年间减少了0.04%。季节分布上,夏季出现水云的概率最高(31.7%),春季出现冰云的概率最高(26.5%)。每年出现的冰云比水云高2%左右。在全球变暖背景下,青藏高原上空水汽含量呈减少趋势,云水含量呈逐渐增加趋势。年平均云水含量比大气总水汽含量高约0.01 cm,云水总含量增加约0.04 cm。本研究为理解云水资源对全球气候变化和青藏高原地区水循环的影响提供了依据。  相似文献   

4.
利用1994—2009年国际卫星云气候计划ISCCP中D2卫星观测月平均云数据集,从不同区域、不同云类角度出发,详细分析中国地区云量、云水路径、云光学厚度的时空分布特征。结果表明:(1)中国地区大部分水云分布在四川盆地至东南沿海一带,而大部分冰云分布在北方和青藏高原地区,其中卷云覆盖最广、云量最大,其次为卷层云、水高层云、水积云,而冰云中低云云量最小。(2)水云中层积云、雨层云和冰云中深对流云总云量、云水路径和云光学厚度均较大,云水含量丰富,对四川盆地至东南沿海一带降水贡献较大。(3)不同云类的总云量季节变化明显,不同区域表现不一,多数水云尤其是雨层云在北方和高原地区夏多冬少,而在西南和东南地区冬多夏少;冰云季节变化的地域性差异较小,多数区域高积云和高层云冬多夏少,卷层云和深对流云夏多冬少,表明冬季对流减弱使得冰云集聚且向中低层发展,而夏季温度升高、对流增强使得水云集聚并向高层发展。(4)水云中层云和雨层云的云水路径有明显的季节变化,且地域性特征明显,尤其是东南地区,表现为双峰型分布,峰值分别在2月和11月;冰云的云水路径在北方地区夏季达到峰值,而在南方地区冬季达到峰值。  相似文献   

5.
东亚季风气候受到自然因素和人类活动的共同影响,而人类活动因子中气溶胶的作用尤为关键,采用诊断分析的手段研究东亚地区气溶胶的特征及其与云和降水的相互关系具有重要的科学意义。本文利用MODIS(moderate-resolution imaging spectroradiometer)气溶胶和云资料以及TRMM(Tropical Rainfall Measuring Mission)降水数据,分析了东亚夏季气溶胶、云、降水的时空分布特征,研究了气溶胶与云和降水的相互关系。结果表明:中国四个典型地区(珠三角、长三角、四川盆地、京津唐)2001~2011年夏季(6~8月)平均气溶胶光学厚度(Aerosol Optical Depth, AOD)变化范围为0.40~0.68,云光学厚度平均值为18.7~23.6,水云云滴有效粒子半径在20.2~25.6 μm,冰云有效粒子半径在12.9~15.3 μm,云水路径为222.2~243.8 g m-2,降水强度平均值3.6~8.6 mm d-1;珠三角气溶胶光学厚度有显著降低趋势,年倾向为-3.31%,四川盆地云滴有效粒子半径(冰云、水云)和云水路径年变化趋势为-0.42%、-0.49%和-1.26%,京津唐夏季降水量年增幅为3.24%。气溶胶光学厚度和云光学厚度呈正相关,相关系数最大为0.77;在相对湿度较低(30%~50%)情况下,气溶胶光学厚度与云滴有效粒子半径呈负相关;气溶胶光学厚度与云水路径呈正相关,相关系数最大为0.92;相对于低污染情况(AOD<0.5),高污染情况(AOD>0.5)下出现大雨(>10 mm d-1)的频率增加了6.6%~19.1%,小雨(<1 mm d-1)的频率减少了0.72%~7.3%。在水汽含量较少的情况下,气溶胶的增加导致云滴有效粒子半径的减少;气溶胶增强了南方地区的对流性降水,抑制了北方地区层云降水。  相似文献   

6.
中国地区夏季云粒子尺寸的时空分布特征   总被引:5,自引:1,他引:4  
利用CloudSat卫星资料,分析了2006~2008年中国地区夏季月平均云粒子有效半径的垂直和区域变化特征。结果显示,水云粒子有效半径在对流层低层达到最大,并随高度增加而减小。30°N纬度带的水云相对以南及以北纬度带的粒子有效半径偏大。6月水云粒子有效半径较大,应与梅雨季节有密切联系。对于中国北部和中部,水云粒子有效半径在西部较东部偏大,而在南部地区,东西部差异不明显。不同纬度带上的冰云粒子有效半径相类似,在冰云下边界最大,随高度增加而减小。水云和冰云的云粒子尺度的年际变化不明显。对上述特征的成因分析表明,高原地形以及东亚夏季风对月平均云粒子有效半径具有明显影响。所揭示的云粒子有效半径特征为天气和气候模式改进、人工影响天气及云—辐射—气候相互作用等研究提供了重要的基础信息。  相似文献   

7.
利用欧洲中期数值预报中心(ECMWF)发布的第5代全球大气再分析资料(ERA5),结合中国气象局人工影响天气中心发布的CWR-MEM方案云水资源监测评估方法,对广西区域2009—2018年云水资源进行评估研究,结果表明:广西年均云水资源总量约5107.8×10~8 t,其中年均空中留存云水总量约1422.2×10~8 t,云水以区域内生成为主,年均约净输出197.1×10~8 t云水资源。广西云水资源存在明显的季节变化特征,呈单峰分布,夏季6月最高,冬季2月最低,空中留存云水无明显季节变化。广西云水水平分布总体呈东北部高,向西和向南逐渐降低的分布特征。广西秋、冬和春季云水主要分布在低层925~600hPa,是以液相水滴构成的暖性层状云云水为主,夏季云水则主要分布在中层600~400hPa,是以过冷液水滴和冰相粒子构成的混合态云水为主,低层云水显著减少。  相似文献   

8.
利用欧洲中期天气预报中心(ECMWF)发布的新一代全球分辨率ERA-Interim再分析数据,用九点平滑、一元线性回归法分析了1979-2016年中国云水量时空分布特征和变化趋势。结果表明:(1)中国云水含量和云液水含量大值区主要位于四川东部-湖南850~500 h Pa,量值达0. 015~0. 045 g·kg~(-1),这一分布与该地区层状云的富集有关。云冰水含量大值区主要位于中东部地区(27°N-35°N,97°E-110°E) 500~250 hPa,量值达0. 006~0. 025 g·kg~(-1)。三者小值区均位于西北地区西部。(2)中国多年平均整层云水量无明显线性趋势。春季云水量呈略减少,秋、冬季呈略增加趋势,夏季无明显趋势。云水量有明显年际变化,夏季年际变化远小于其他季节;干旱区、半干旱区整层云液态水含量的年际变化大于湿润区,云冰水含量相反。云水量空间变化呈西增东减趋势。(3)云水量大值区对应水汽输送辐合和低层上升运动,且对流层中低层水汽通量散度可在一定程度上表征云水含量。从而为认识和理解气候变化对中国水资源的影响提供一定依据。  相似文献   

9.
利用欧洲中心再分析资料,结合探空资料与内陆河径流量资料,分析了祁连山区空中水汽含量和水汽年内变化及多年演变特征。结果表明:祁连山单位面积垂直累积水汽含量随季节变化差异大,夏季最高,秋季次之,冬季最低,与以往认识不同的是在适宜天气条件下,祁连山春季空中水汽也具有开发前景。此外,祁连山东段水汽含量一年四季都高于西段,在祁连山西段山区中稳定存在一水汽低值中心,这是以往资料空间分辨率不高时未曾认识到的,该低值中心年内水汽差异很大,夏季是冬季的6倍之多;水汽密度分布与之类似。祁连山区逐月单位面积垂直累积水汽含量呈单峰型变化,6-9月是水汽分布最多的时段,进入冬季起水汽含量快速减少。近37年来,祁连山区空中水汽年保有量呈现增加趋势,这也与同时段疏勒河与黑河径流量的逐步上升趋势是一致的,但不同季节表现态势不同,夏、秋季整体呈增加趋势,冬、春季呈减少趋势。  相似文献   

10.
本文利用NASA发布的MODIS气溶胶光学厚度产品,对西南地区2001~2016年气溶胶光度厚度空间分布和时间演变特征进行了分析,研究发现:(1)西南地区年均气溶胶光学厚度空间分布特征整体表现为东部高于西部,海拔低的地区气溶胶光学厚度高于海拔高的地区。高值中心位于四川盆地南部,低值区位于川西高原和云南北部地区。(2)西南地区季节气溶胶光学厚度空间分布特征与年均相似。(3)就西南各地区而言,重庆气溶胶光学厚度最大,其次是四川盆地和贵州地区,再次是云南地区,川西高原地区气溶胶光学厚度最小。(4)2001~2016年,西南地区年均气溶胶光学厚度呈显著减少趋势。夏季和秋季气溶胶光学厚度年际变化浮动较大,也具有显著的减少趋势。   相似文献   

11.
Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d.  相似文献   

12.
Based on the measurements obtained at 64 national meteorological stations in the Beijing–Tianjin–Hebei (BTH) region between 1970 and 2013, the potential evapotranspiration (ET0) in this region was estimated using the Penman–Monteith equation and its sensitivity to maximum temperature (Tmax), minimum temperature (Tmin), wind speed (Vw), net radiation (Rn) and water vapor pressure (Pwv) was analyzed, respectively. The results are shown as follows. (1) The climatic elements in the BTH region underwent significant changes in the study period. Vw and Rn decreased significantly, whereas Tmin, Tmax and Pwv increased considerably. (2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwv in the fall and winter and Rn in the spring and summer. On the annual scale, ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmax and Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwv had a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing. (3) The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However, increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the "evaporation paradox" phenomenon in the BTH region.  相似文献   

13.
Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms.  相似文献   

14.
The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics.  相似文献   

15.
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome.SUBMISSIONAll submitted  相似文献   

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17.
<正>With the support of specialized funds for national science institutions,the Guangzhou Institute of Tropical and Marine Meteorology,China Meteorological Administration set up in October 2008 an experiment base for marine meteorology and a number of observation systems for the coastal boundary layer,air-sea flux,marine environmental elements,and basic meteorological elements at Bohe town,Maoming city,Guangdong province,in the northern part of the South China Sea.  相似文献   

18.
《大气和海洋科学快报》2014,7(6):F0003-F0003
AIMS AND SCOPE
Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome.  相似文献   

19.
《大气和海洋科学快报》2014,(5):F0003-F0003
AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) pub- lishes short research letters on all disciplines of the atmos- phere sciences and physical oceanography. Contributions from all over the world are welcome.  相似文献   

20.
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences  相似文献   

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