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1.
广西冬季严重冻害的环流特征 总被引：5，自引：0，他引：5
利用广西1960－2000年冬季冻害站次资料，根据规定的指标，划分出广西冬季严重冻害年有12年，将12个严重冻害年的500hPa高度场进行合成，分析了广西冬季严重冻害当年和前一年的500hPa高度合成距平场特征以及前期主要影响月的500hPa高度合成距平场的主要特点，为广西冬季严重冻害的预测提供判别依据。 相似文献
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华东冬季异常冷暖与大气环流和海温的关系 总被引：7，自引：5，他引：2
利用1951-2007年华东地区14个代表站冬季(12-2月)温度资料和北半球500 hPa高度及北太平洋海温资料,通过合成分析、相关分析等方法,研究了华东地区冬季气温的气候变化及其与北半球500 hPa高度场、北太平洋海温场的关系.结果表明:华东地区冬季气温具有明显的年代际气候变化特征;前期夏季北半球500 hPa高度距平场和前期春季北太平洋海温距平场分布可作为华东冬季异常冷暖年的前兆信号;夏季北太平洋中部地区500 hPa高度场变化及前期10月西太平洋副高强弱变化,对华东地区冬季气温变化具有很好的指示性;春季南赤道海流区和西风漂流区海温异常变化,对华东地区冬季气温变化也具有很好的指示意义. 相似文献
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广西冬季严重冻害的前期强信号及预测概念模型 总被引：3，自引：0，他引：3
利用500hPa高度场、北太平洋海温场、青藏高原积雪以及表征大气活动特征的物理量等资料，从多方面较为系统地研究广西冬季严重冻害的前期强信号，最后形成预测概念模型，为广西冬季严重冻害的预测提供多方面的信息。 相似文献
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近40a江苏省冬季气温异常的演变及其涨气背景场特征 总被引：6，自引：1，他引：6
通过1961－1998年江苏省11个站点冬季平均气温的EOF分析，探讨江苏省冬温异常的演变特征，并分析其同期及前期500hPa高度距均，海温距平场的特征，指出冬季异常冷年，同期与前期500mPa高度距平场主要表现为亚洲－太平洋地区阻塞形势发展，经向环流加强，同期至前期6个月赤道东太平洋海温为持续负距平。而暖冬同期与前期500hPa高度距平场的特征特征是，西太平洋海温为持续负距平。而暖冬同期与前期500hPa高度距平场的特征是，西太平洋副高势力较强，亚欧大陆中高纬 纬向环流占优势，同期赤道东太平洋海温具有厄尔尼诺的特征，但前期赤道东太平洋海温距平具有由负向正转变特征。 相似文献
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贵州省冬季气温的时空特征及其与海气的关系 总被引：1，自引：0，他引：1
《高原气象》2017,(5)
利用1962—2014年贵州39个代表站的冬季(12月至次年2月)温度资料和北半球500 hPa高度场及全球海温资料,通过合成分析、相关分析和小波分析等方法,对贵州冬季气温的时空特征及其与北半球500 hPa高度场、全球海温场的关系进行了研究。结果表明,近53年来,贵州冬季平均气温约为6.3℃,整体呈升温趋势,在贵州省东北部和西南部边缘最为显著;贵州冬季气温以准7年和准12年的振荡周期为主;贵州冬季气温突变于1988年,突变前贵州冷冬明显,突变后暖冬明显。异常暖冬年,格陵兰、北美和中太平洋地区的500 hPa高度场呈正距平,其余地区均为负距平,欧亚大陆的位势高度距平呈现为经向的"正-负-正"分布;异常冷冬年,在中西伯利亚地区、西欧-北大西洋和北美高度场表现为明显的正距平,其余地区均为负距平,在东半球,位势高度距平从西到东、从北到南都表现出"负-正-负"的分布形势。贵州冬季气温与前期秋季东北太平洋、赤道东太平洋和东印度洋区域的海温有显著的相关关系。异常暖冬年前期秋季,北太平洋(尤其是西北太平洋)和中印度洋(最显著)的海温距平异常显著;异常冷冬年前期秋季,北半球中东太平洋(最显著)和中印度洋的海温距平异常显著。同时,异常冷暖冬年的海温距平差值中心集中在东北太平洋和南半球中印度洋海域。 相似文献
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大连地区冷暖冬年冬季大气环流特征分析 总被引：6，自引：4，他引：2
利用合成分析方法,对大连地区1960--2000年冷暖冬年冬季的环流形势进行了对比分析。结果表明：在冷暖冬年冬季,海平面气压距平场、500hPa高度距平场、300hPa纬向风距平场都存在着显著的差异,其中蒙古高压、极涡的位置、面积、强度及东亚西风环流指数、极锋急流差异都显著,说明极锋急流、极涡、乌山脊、东亚大槽及蒙古高压等都是影响大连冬季气温异常的关键系统。 相似文献
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SVD方法在前期500hPa环流与贵州春季降水关系中的应用 总被引：1，自引：0，他引：1
基于500hPa高度场资料和贵州春季降水场资料,采用奇异值分解(SVD)方法,分析高度场与降水场的关系。结果表明:奇异值分解方法前8个奇异向量占总方差的80%以上,取前8个奇异向量已能代表贵州春季降水的主要分布;春季降水与前期冬季500hPa高度场分布有很好的匹配关系,且不同年份可能呈反位相分布;贵州春季降水除了通常的一致偏多(或偏少)外,还存在东南—西北准对称型分布;当冬季500hPa高度场距平场呈反位相分布时,即除北美地区负距平外,其余地区均呈中低纬负距平、高纬度正距平分布,贵州春季降水为一致的正距平分布。 相似文献
9.
利用1967～1997年500hPa高度场及同期副热带高压资料,分别将年、春、夏、秋、冬季的青藏高原积雪与这两者之间的联系进行分析,并"借用"他人通过数值模拟所得结果来印证由统计分析而得到的相关关系,从而揭示青藏高原积雪对广西气候影响的过程和物理机制。结果表明:青藏高原积雪多、少雪年时,在高原主体所处的范围以及我国以北以贝加尔湖为中心的区域范围内,500hPa高度场的距平符号呈反向变化形式,高原多雪时,高原主体上层500hPa高度场为负距平,高原少雪时,则为正距平。而青藏高原多雪时,太平洋副热带高压脊线要比少雪年位置偏南。 相似文献
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Using the International Comprehensive Ocean-Atmosphere Data Set(ICOADS) and ERA-Interim data, spatial distributions of air-sea temperature difference(ASTD) in the South China Sea(SCS) for the past 35 years are compared,and variations of spatial and temporal distributions of ASTD in this region are addressed using empirical orthogonal function decomposition and wavelet analysis methods. The results indicate that both ICOADS and ERA-Interim data can reflect actual distribution characteristics of ASTD in the SCS, but values of ASTD from the ERA-Interim data are smaller than those of the ICOADS data in the same region. In addition, the ASTD characteristics from the ERA-Interim data are not obvious inshore. A seesaw-type, north-south distribution of ASTD is dominant in the SCS; i.e., a positive peak in the south is associated with a negative peak in the north in November, and a negative peak in the south is accompanied by a positive peak in the north during April and May. Interannual ASTD variations in summer or autumn are decreasing. There is a seesaw-type distribution of ASTD between Beibu Bay and most of the SCS in summer, and the center of large values is in the Nansha Islands area in autumn. The ASTD in the SCS has a strong quasi-3a oscillation period in all seasons, and a quasi-11 a period in winter and spring. The ASTD is positively correlated with the Nio3.4 index in summer and autumn but negatively correlated in spring and winter. 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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Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 days) on insect migration. A case study was conducted to ascertain the influence of low-frequency atmospheric oscillation on the immigration of brown planthopper, Nilaparvata lugens(Stl), in Hunan and Jiangxi provinces. The results showed the following:(1) The number of immigrating N. lugens from April to June of 2007 through 2016 mainly exhibited a periodic oscillation of 10 to 20 days.(2) The 10-20 d low-frequency number of immigrating N. lugens was significantly correlated with a low-frequency wind field and a geopotential height field at 850 h Pa.(3) During the peak phase of immigration, southwest or south winds served as a driving force and carried N. lugens populations northward, and when in the back of the trough and the front of the ridge, the downward airflow created a favorable condition for N. lugens to land in the study area. In conclusion, the northward migration of N. lugens was influenced by a low-frequency atmospheric circulation based on the analysis of dynamics. This study was the first research connecting atmospheric low-frequency oscillation to insect migration. 相似文献
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The atmospheric and oceanic conditions before the onset of EP El Ni?o and CP El Ni?o in nearly 30 years are compared and analyzed by using 850 hPa wind, 20℃ isotherm depth, sea surface temperature and the Wheeler and Hendon index. The results are as follows: In the western equatorial Pacific, the occurrence of the anomalously strong westerly winds of the EP El Ni?o is earlier than that of the CP El Ni?o. Its intensity is far stronger than that of the CP El Ni?o. Two months before the El Ni?o, the anomaly westerly winds of the EP El Ni?o have extended to the eastern Pacific region, while the westerly wind anomaly of the CP El Ni?o can only extend to the west of the dateline three months before the El Ni?o and later stay there. Unlike the EP El Ni?o, the CP El Ni?o is always associated with easterly wind anomaly in the eastern equatorial Pacific before its onset. The thermocline depth anomaly of the EP El Ni?o can significantly move eastward and deepen. In addition, we also find that the evolution of thermocline is ahead of the development of the sea surface temperature for the EP El Ni?o. The strong MJO activity of the EP El Ni?o in the western and central Pacific is earlier than that of the CP El Ni?o. Measured by the standard deviation of the zonal wind square, the intensity of MJO activity of the EP El Ni?o is significantly greater than that of the CP El Ni?o before the onset of El Ni?o. 相似文献
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Fei LIU Chen XING Jinbao LI Bin WANG Jing CHAI Chaochao GAO Gang HUANG Jian LIU Deliang CHEN 《大气科学进展》2020,37(7):663-670
正The Taal Volcano in Luzon is one of the most active and dangerous volcanoes of the Philippines. A recent eruption occurred on 12 January 2020(Fig. 1a), and this volcano is still active with the occurrence of volcanic earthquakes. The eruption has become a deep concern worldwide, not only for its damage on local society, but also for potential hazardous consequences on the Earth's climate and environment. 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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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
19.
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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