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1.
为了了解区域云顶高度对过去气候变化的响应,基于卫星搭载的MODIS传感器提供的2000年3月至2018年2月MOD03_08_v6.0数据,分析了东亚地区云顶高度2000—2018年的时空变化特征,并探讨其长期变化的原因。研究发现,东亚地区云顶高度呈西南高东北低的特征。云顶高度在东亚地区以0.020 km/a的变率增长,其中大陆东部云顶高度的年际变率为0.035 km/a,东部海域年际变率为0.034 km/a。在东部海域地区云顶高度的变化同海表温度的变化相关性较高,相关系数为0.68,这表明云顶高度的变化受下垫面的影响。在东亚地区30°~40°N区域内,年平均云顶高度的增加较为明显。此外,夏季云顶高度在长江中下游盆地、塔里木盆地、吐鲁番盆地以及四川盆地东北部呈-0.03 km/a的减少趋势,这是由于更多低云的形成降低了云顶高度;冬季云顶高度在东亚地区40°N以北呈下降趋势,而在40°N以南呈增加趋势。 相似文献
2.
温湿变化的年代际特征及区域差异是全球气候变化研究的重要内容之一。利用1901-2014年东英吉利大学气候研究中心(CRU)TS3.20月地表温度和降水资料分析了东亚和北美地区温度和降水变化的季节性和区域特征,并利用1979-2015年欧洲中心天气预报中心(ECMWF)ERA-Interim日最高/最低温和降水资料进一步分析了东亚和北美地区受极端天气影响的区域所占比例的年际变化。结果发现,近110多年来东亚地区[0.134℃·(10a)~(-1)]的增温趋势高于北美地区[0.102℃·(10a)~(-1)],东亚干旱半干旱区的增温趋势低于东亚地区,而北美干旱半干旱区的增温趋势高于北美地区。季节性特征表现为在冷季增温明显,东亚地区冷季增温约是暖季的2.9倍,北美地区为1.3倍。季节性增温存在明显的纬度差异,在东亚和北美高纬度地区(45°N以北)冷季温度的增长速率通常比暖季大。东亚和北美的降水增加趋势均高于北半球,暖季降水增加明显并且主要发生在东亚和北美高纬度地区(45°N以北)。东亚和北美的干旱半干旱区的降水没有明显增加趋势,分别为0.04 mm·(10a)~(-1)和0.07 mm·(10a)~(-1)。东亚和北美地区及东亚和北美的干旱半干旱区受极端高温影响的面积有增加趋势,受极端低温影响的面积没有明显变化,受极端降水影响的面积有减少趋势。北美和东亚地区以及北美和东亚干旱半干旱区的月平均温度对PDO(Pacific Decadal Oscillation)的响应比ENSO(El Nino Southern Oscillation)明显,月平均降水对ENSO的响应比PDO明显。 相似文献
3.
青藏高原对流时空变化与东亚环流的关系 总被引：4，自引：3，他引：4
根据1980～1998年逐日TBB和NCEP/NCAR再分析资料,探讨青藏高原对流(TBB)时空分布与东亚环流及天气气候的关系.研究指出,青藏高原主体地区(28°N～34°N,80°E～102°E)的对流冬弱、夏强,存在显著的6月和10月突变现象.夏季亚洲地区最强的对流出现在青藏高原上空,呈现为高原西部(28°N～34°N,82°E～94°E)和东部(27°N～34°N,104°E～110°E)型.夏季青藏高原上空对流弱,850 hPa风场上高原南、北侧的东亚地区分别呈现西风距平,夏季中国易出现南北二条雨带; 夏季高原上空对流强,850 hPa风场上的西风距平出现在东亚30°N附近,夏季易出现江淮流域雨带.夏季江淮流域洪涝年(如1980、1993、1996、1998年)与青藏高原东、西部对流同时加强有关; 夏季江淮流域干旱年(如1992、1994、1997年)与青藏高原东、西部对流同时减弱有关.20世纪90年代,江淮流域洪涝与干旱事件频繁发生可能与青藏高原东、西部对流强度变化出现同位相的年代际变化趋势有关. 相似文献
4.
近40年来塔什干低涡活动特征的统计分析 总被引：1，自引：0，他引：1
利用1971-2010年NCEP/NCAR逐日再分析资料,根据塔什干低涡定义,分析了塔什干低涡的时空分布特征、移动路径及其对南疆天气的影响.结果表明:(1)1971-2010年,塔什干低涡过程平均每年出现7.95次,成熟期生命史平均为3.1天,4天以上的仅有13.5％; (2)4-6月和9-10月是塔什干低涡活动的两个高峰期,其中5月出现次数最多,其次是10月和6月;(3)塔什干低涡频次的年代际变化呈抛物线型,1970-1980年代由78次增加到83次,之后逐渐减少,年低涡频次存在7年左右的显著振荡周期,同时具有1 3年的次振荡周期;(4)塔什干低涡活动有两个高频中心,分别位于67.5°E,40.0°N和72.5°E,35.0°N,移动路径以偏东方向为主,占84％,西退塔什干低涡仅有5.7％;造成南疆显著降水天气的塔什干低涡占其总数的23.3％,夏季此类低涡所占比例最高,达41.2％. 相似文献
5.
基于1958~2002年ECMWF再分析资料,我国160个台站降水和气温资料,从夏季高原季风环流系统特点出发,定义了能较好表征高原夏季风环流变化的特征指数,分析了高原夏季风年际、年代际变化特征,并揭示了高原夏季风强弱异常时的环流特征及其与中国夏季降水和气温的关系,主要结论为:(1)用6~8月600hPa(27.5~30°N,80~100°E)范围内平均的西风分量距平与(35~37.5°N,80~100°E)范围内平均的东风分量距平差定义了高原夏季风指数(PM I)。该指数计算简单,意义清楚,代表性好。(2)1958~2002年高原夏季风整体呈增强趋势,在20世纪60年代中期之前是高原夏季风的强盛期,之后是高原夏季风弱期,在80年代以后又转为季风强期。(3)高原夏季风与中国夏季降水和气温相关很好。将该指数与之前汤懋苍定义的指数进行性能综合比较后,发现该指数对川渝地区的夏季降水及气温有更好的指示意义。 相似文献
6.
高原夏季风指数的定义及其特征分析 总被引：6，自引：0，他引：6
基于1958~2002年ECMWF再分析资料,我国160个台站降水和气温资料,从夏季高原季风环流系统特点出发,定义了能较好表征高原夏季风环流变化的特征指数,分析了高原夏季风年际、年代际变化特征,并揭示了高原夏季风强弱异常时的环流特征及其与中国夏季降水和气温的关系,主要结论为:(1)用6~8月600hPa (27.5~30°N,80~100°E)范围内平均的西风分量距平与(35~37.5°N,80~100°E)范围内平均的东风分量距平差定义了高原夏季风指数(PM I)。该指数计算简单,意义清楚,代表性好。(2)1958~2002年高原夏季风整体呈增强趋势,在20世纪60年代中期之前是高原夏季风的强盛期,之后是高原夏季风弱期,在80年代以后又转为季风强期。(3)高原夏季风与中国夏季降水和气温相关很好。将该指数与之前汤懋苍定义的指数进行性能综合比较后,发现该指数对川渝地区的夏季降水及气温有更好的指示意义。 相似文献
7.
文中从东亚冬季风系统特点出发,定义了能较好表征东亚冬季风环流年际变化和青藏高原温度降水变化特征的冬季风指数,并分析了冬季风指数的年际变化与青藏高原温度降水的关系。文中定义的冬季风指数既反映了冬季东亚大气环流场的变化特征,也较好地反映了青藏高原温度降水的年际变化特征,当冬季北半球500hpa高度场东亚大槽位置相对偏南偏西(20~35°N,110~130°E)时,其强度与青藏高原同期冬季温度降水、后期春、夏、秋季的温度有很好的相关关系。此外,还探讨了冬季风指数变化的先兆信号。 相似文献
8.
利用CAM3.0气候模式模拟研究东亚地区气溶胶浓度增长以及1976/1977年前后发生的海温年代际变化对东亚夏季降水场的影响及其机制。采用四组试验:即对东亚区域(100~150 °E,20~50 °N)分别进行的单独加倍黑碳气溶胶浓度、单独加倍硫酸盐气溶胶浓度、同时加倍这两种气溶胶浓度的三组关于气溶胶直接气候效应的试验及全球海温在1976/1977前后发生变化的海温年代际变化试验,来比较、探讨海温年代际变化和东亚地区气溶胶浓度增加对东亚夏季降水的影响机制。结果表明,无论是海温年代际变化还是各种气溶胶的浓度加倍,都能导致我国出现长江以北地区降水减少-东南沿海地区降水增加的“南涝北旱”的降水异常分布型。但两者在洋面上空降水的迥异表现及东亚低层风场的不同变化,显示其具有不同的异常降水机制。比较三类气溶胶浓度增加的试验结果发现:在单独硫酸盐气溶胶浓度增加试验中,东亚中部出现最显著的中下层大气降温、异常下沉气流以及降水减少;而在黑碳气溶胶试验中,出现在东亚中部的异常下沉气流强度减弱且位置偏南;在同时增加两类气溶胶浓度时,降水异常分布与单独黑碳气溶胶浓度增加所导致的降水异常相近,但强度减小。 相似文献
9.
青藏高原地区地表热力异常与夏季东亚环流和江淮降水的关系 总被引：7，自引：2，他引：5
利用NCEP/NCAR再分析月平均资料和中国160个站降水资料,以及由国家气候中心提供的西太平洋副高脊线指数资料,分析了青藏高原地区多年平均地表温度季节转换(3-6月)的空间特征,结合均方差分析,确定高原主体(28°-38°N,75°-100°E)、高原东部以北区域(38°-48°N,90°-105°E)和高原西部以北区域(38°-45°N,75°-90°E)为关键区,分析了1951-2002年5月不同关键Ⅸ地表温度的空间变化与夏季东亚季风环流和江淮降水的关系.结果发现,这3个区域地表温度异常均对夏季东哑850 hPa环流有显著的影响.5月高原和其以北区域地表温度异常存在较大尺度的热力对比,由此,将高原主体和其以北区域的温度异常之差定义为一个指数,反映这种热力差异.相关分析发现:当5月这一热力差异增大(减小)时,夏季东亚中高纬的中高层(500-200 hPa平均)西风加强(减弱),且两风中心轴线位簧南移(北抬);造成西太平洋副热带高压脊线位置偏南(偏北),致使夏季东亚季风环流偏弱(偏强),江淮流域降水增多(减少). 相似文献
10.
基于云亮温和降水回波顶高度分类的夏季青藏高原降水研究 总被引：7，自引：0，他引：7
本文利用热带测雨卫星(TRMM, Tropical Rain Measuring Mission)第七版逐日逐轨测雨雷达(PR, Precipitation Radar)及可见光和红外扫描仪(VIRS, Visible and Infrared Scanner)的融合数据集,研究了夏季青藏高原上降水类型的特征.统计结果表明第七版PR降水回波强度及降水率廓线资料(2A25)仍旧误判青藏高原上以层云降水为主(比例高达85%);以云顶相态定义的青藏高原降水类型统计表明,冰相云顶和冰水混合相云顶的降水分别占43%和56%;以降水回波顶高度定义的降水类型统计表明,深厚弱对流降水和浅薄降水分别占77%和22%,而深厚强对流降水仅占1%.空间分布的统计表明,冰相云顶降水和冰水混合相云顶降水的频次和强度自高原西部向高原东部和东南部增加,其降水回波顶高度自高原西、中部向东部降低.深厚强对流降水和浅薄降水的频次由西向东增加,而深厚弱对流降水频次分布是西少、北少、南多,高原南部比北部的深厚弱对流降水频次高出近1倍;深厚弱对流降水和浅薄降水的平均强度也表现了自高原西部、中部向东部的增大,而其降水回波顶高度分布则相反.总体上,夏季青藏高原降水频次和强度自西向东增多和增大,而云顶和降水回波顶高度则相反. 相似文献
11.
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
12.
Yuepeng PAN Mengna GU Yuexin HE Dianming WU Chunyan LIU Linlin SONG Shili TIAN Xuemei Lü Yang SUN Tao SONG Wendell W. WALTERS Xuejun LIU Nicholas A. MARTIN Qianqian ZHANG Yunting FANG Valerio FERRACCI Yuesi WANG 《大气科学进展》2020,37(9):933-938
正While China’s Air Pollution Prevention and Control Action Plan on particulate matter since 2013 has reduced sulfate significantly, aerosol ammonium nitrate remains high in East China. As the high nitrate abundances are strongly linked with ammonia, reducing ammonia emissions is becoming increasingly important to improve the air quality of China. Although satellite data provide evidence of substantial increases in atmospheric ammonia concentrations over major agricultural regions, long-term surface observation of ammonia concentrations are sparse. In addition, there is still no consensus on 相似文献
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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
14.
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
15.
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
16.
《大气和海洋科学快报》2013,(4):227
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. 相似文献
17.
《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
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
18.
《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
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20.
《大气科学进展》2014,(6)
正Aims Scope Advances in Atmospheric Sciences(AAS)is an international journal on the dynamics,physics,and chemistry of the atmosphere and ocean with papers across the full range of the atmospheric sciences,co-published bimonthly by Science Press and Springer.The journal includes Articles,Note and Correspondence,and Letters.Contributions from all over the world are welcome. 相似文献