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2010年华南前汛期持续性降水异常与准双周振荡 总被引：3，自引：1，他引：3
利用中国台站逐日降水资料以及NCEP-DOE逐日再分析资料,分析了2010年华南汛期降水异常的低频特征及大气环流的影响。结果表明,2010年华南汛期降水异常呈显著的低频振荡特征,其中前汛期以10~20天振荡（准双周振荡）为主,后汛期以20~50天振荡（季节内振荡）为主。重点讨论了准双周尺度上前汛期持续性降水异常与中高纬和热带地区大气低频振荡的关系。中高纬地区的低频环流可通过Rossby波能量沿着低频遥相关波列的频散影响华南低频环流的变化。波活动通量分析显示,西西伯利亚作为Rossby波源,其波能量沿着横跨欧亚大陆的低频遥相关波列向我国东部地区频散,引起该地扰动加强,从而引起华南低频环流及垂直运动的变化进而造成华南降水的异常。热带东印度洋的准双周振荡是影响华南前汛期降水的另一低频来源。当赤道东印度洋对流旺盛（抑制）,其上空为强上升（下沉）气流,低层辐合（辐散）高层辐散（辐合）,而华南上空盛行下沉（上升）运动,不利于（有利于）华南降水。来自中高纬和低纬的低频信号的叠加并配合低频水汽输送共同影响了华南环流异常的低频变化,从而引起华南的低频降水异常,有利于华南持续性降水异常的发生。 相似文献
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《热带气象学报》2017,(华南前汛)
利用中国台站逐日降水资料以及NCEP-DOE逐日再分析资料,分析了2010年华南汛期降水异常的低频特征及大气环流的影响。结果表明,2010年华南汛期降水异常呈显著的低频振荡特征,其中前汛期以10~20天振荡(准双周振荡)为主,后汛期以20~50天振荡(季节内振荡)为主。重点讨论了准双周尺度上前汛期持续性降水异常与中高纬和热带地区大气低频振荡的关系。中高纬地区的低频环流可通过Rossby波能量沿着低频遥相关波列的频散影响华南低频环流的变化。波活动通量分析显示,西西伯利亚作为Rossby波源,其波能量沿着横跨欧亚大陆的低频遥相关波列向我国东部地区频散,引起该地扰动加强,从而引起华南低频环流及垂直运动的变化进而造成华南降水的异常。热带东印度洋的准双周振荡是影响华南前汛期降水的另一低频来源。当赤道东印度洋对流旺盛(抑制),其上空为强上升(下沉)气流,低层辐合(辐散)高层辐散(辐合),而华南上空盛行下沉(上升)运动,不利于(有利于)华南降水。来自中高纬和低纬的低频信号的叠加并配合低频水汽输送共同影响了华南环流异常的低频变化,从而引起华南的低频降水异常,有利于华南持续性降水异常的发生。 相似文献
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利用1979—1998年NCEP/DOE逐日再分析资料和国家气象信息中心的常规观测站资料,研究了1997/1998年冬季、1998年夏季青藏高原 (简称高原) 季风的低频振荡特征,研究夏季高原和周边区域高低层大气低频环流系统的配置及其与我国降水的联系。结果表明:1997/1998年冬季和1998年夏季,高原季风不仅表现出很强的30~60 d的周期振荡特征,还伴随有较强的准双周低频振荡;相应区域对流层上层200 hPa上的环流系统则是30~60 d为主的周期变化。1998年夏季,高原地面气压也存在两个频带的低频振荡变化,且其强度存在明显的经向变化,即自南向北30~60 d低频振荡信号有逐渐减弱趋势,准双周信号则呈增强趋势。对30~60 d的低频信号而言,高原夏季风低频信号较强 (弱) 时,高原地面表现为低频低 (高) 压环流系统,在同纬度带的我国东部地区和西太平洋沿岸,是较强的低频北 (南) 风和低 (高) 压环流系统;相应地,在80°~90°E之间,自孟加拉湾到我国西北中部地区,是低频反气旋-气旋-反气旋的经向低频波列;受低频环流系统影响,高原东部、长江中下游地区降水偏多 (少)、川西高原、云南西南部降水偏少 (多)。 相似文献
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利用1961—2018年湖北省68站逐日降水资料和美国国家海洋和大气管理局（NCEP/NCAR）环流、海温资料，分析了湖北省春季降水低频特征，并讨论了其年际变化与海温的联系。结果表明：①湖北省春季降水存在显著的准双周低频周期。春季涝（旱）年，准双周活动活跃（不活跃）。②春季印度洋和黑潮海温分别通过影响中低纬、日本海附近不同区域上空的环流，进而影响湖北省春季降水的低频活动。③2018年受黑潮海温异常偏暖的影响，日本海附近500 hPa高度场呈正距平，具有明显的低频振荡特征，其后部东南气流和华南上空的西南气流构成了暖切，从而给湖北省带来低频降水，造成当年春季降水准双周活动指数异常。 相似文献
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针对长江下游典型涝年（1999、2016和2020年）,通过全域功率谱分析和Lanczos滤波方法提取准双周振荡（QBWO）分量;并采用再分析资料进行同位相合成,揭示不同典型涝年共性特征及其各自的关键影响因子。结果表明：（1）1999、2016和2020年是长江下游地区最为典型的涝年,存在10—20 d显著的准双周振荡周期,且6—7月更为明显。（2）中、高纬度地区高层低频环流呈现扰动波列分布,有利于“两脊一槽”大尺度背景的维持和下游扰动增强,引起长江下游地区低频垂直运动变化,进而造成降水异常。低纬度地区准双周振荡是长江下游低频变化的另一来源,低层低频涡旋以10°N为轴对称分布,低频辐散风由中国南海指向长江下游地区,热带对流活动低频变化可通过低频大气环流影响长江下游降水。高、低纬度低频大气环流配合热源强迫存在相向运动,叠加低频水汽强烈辐合,为长江下游地区降水偏多提供有利条件。（3）3个长江下游典型涝年降水分布特征及其关键影响因子存在不同。1999年,西北太平洋上低频反气旋环流偏强、偏西,辐散风由中国南海指向长江下游地区,低频水汽来源为孟加拉湾和中国南海地区。2016年,对流层低层南、北低... 相似文献
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本文能过对美国宇航局Ｎｉｍｂｕｓ－７卫星观测的１９７９－１９８６年中国西部积雪资料的分析发现，２－３周的低频振荡现象普遍存在并与大气环流异常密切相关；大气环流对半年积雪２－３周的低频振荡有着明显的线性响应；冬半年积雪的这种低频振荡能激发出北半球５００ｈＰａ高度场准定常Ｒｏｓｓｂｙ波，并通过二维的Ｒｏｓｓｂｙ波能量频散而影响到北美。 相似文献
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广东前汛期降水与南海北部风场准双周振荡的关系 总被引：2，自引：0，他引：2
利用1961—2008年广东逐日降水、NCEP/NCAR逐日再分析资料,先采用EOF分析、相关分析定义了影响广东前汛期降水的850 hPa关键区——“南海北部风场指数”,再利用功率谱分析、Lanczos时间滤波器等方法研究了近48年广东前汛期降水与南海北部风场指数的低频振荡特征,并研究了广东暴雨与南海北部风场指数准双周振荡的关系。结果表明,广东前汛期降水与南海北部风场指数均以准单周、准双周振荡为主,而30～60天的季节内振荡不显著。南海北部风场指数与广东前汛期降水准双周振荡序列存在显著正相关,且明显高于准单周振荡序列的相关。近48年4—6月南海北部风场指数的准双周振荡波峰前后3天(个别4天)的广东省前汛期暴雨出现概率为78.2%。最后利用合成分析方法分析了南海北部风场指数准双周振荡的波峰附近有典型西南风暖区暴雨发生的大气环流场演变特征,可为广东暖区暴雨过程的中期预报提供参考依据。 相似文献
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2002年夏季中高纬大气准双周振荡对华南降水的影响 总被引：1，自引：0，他引：1
利用JRA55大气再分析资料和TRMM卫星降水资料,分析了2002年夏季（5~8月）华南地区降水的低频振荡特征,重点揭示了对其影响显著的中高纬大气季节内振荡的环流结构及演变。小波和功率谱分析表明,2002年夏季华南降水表现为主周期为10~30 d的准双周低频振荡。典型低频降水事件及合成分析指出,准双周降水的强（弱）变化除了受低空西北太平洋副热带高压西伸进入（东移退出）南海的影响以外,还显著地依赖于中高纬地区高空大气环流的季节内振荡。在对流层高层,中高纬度地区存在一支自大西洋经欧亚大陆的气旋—反气旋相间排列的低频波列。该波列在欧亚大陆地区向东南传播,当异常反气旋和气旋分别位于青藏高原和华北上空时,这种偶极型环流之间的高空辐散场有利于华南地区上升运动的发展,因而华南降水偏强;反之,华南降水偏弱。研究还表明,低频波列南移造成了对流层异常温度平流和副热带高层异常绝对涡度的变化,使得华南地区上升与下沉运动交替出现以及相应的经向环流圈反转,从而导致华南准双周振荡干湿位相的转换。局地异常感热加热对干湿位相转换也起一定作用。时滞相关分析发现,当青藏高原地区500 hPa位势高度异常场超前于华南异常降水4 d（即位相差为1/4周期）时,二者出现显著正相关,表明青藏高原地区500 hPa位势高度异常对预测华南地区季节内降水变化有潜在的应用价值。 相似文献
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本文通过对日平均气温进行功率谙分析发现,桂西北冬、春季逐日平均气温均存在着明显的周期振荡,冬季以准一周振荡为主,并存在着准两周振荡和20～40天的低频振荡,春季则以准两周振荡为主。这些主要周期的谱值均有3年左右的变化规律,而且冬季、春季其强弱趋势大致相反。 本文还分析了冬季气温主要振荡周期与春播期低温阴雨的关系,结果为:当冬季主要周期的谱值为弱值时,其次年低温阴雨一般为结束偏晚或总天数偏多;反之,次年低温阴雨结束期偏早或总天数偏少。 相似文献
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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
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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
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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
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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
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《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
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《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
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《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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《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