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利用我国西南和华南地区131个测站1961~2010年近50 a降水和NECP资料,采用线性趋势分析、合成分析、功率谱分析等方法,基于秋季降水距平百分率,研究分析了近50 a我国西南和华南地区各级别秋旱的空间分布及时间变化特征,并初步讨论了各级别干旱形成的原因。结果表明：秋季干旱集中在川东、贵州中东部—华南,中旱、重旱、特旱主要出现在华南;近50 a来秋旱有显著增多的趋势,主要体现在轻旱的增多,而重旱和特旱趋势不明显。1960年代秋旱相对较多,1970年代初至1980年代后期秋旱较少,此后秋旱频繁,其中2002年以后秋旱突变性增多,干旱范围扩大的同时,其强度也在增强;秋旱频率具有显著的2.2 a周期,其中重旱有显著的12 a周期,特旱有显著的2.7 a周期;秋旱频率高的地方连旱频率也高,连旱高频区在川东—渝北、黔中—华南,连续5 a以上的秋旱较少,个别地方可达到6 a。700 h Pa上,西太平洋副热带高压、印缅槽、高原东部槽等是影响西南、华南地区秋季干湿的主要环流因子。 相似文献
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2004年中国长江以南地区严重秋旱特征及其同期大气环流异常 总被引：7，自引：1，他引：7
利用2004年8～10月的中国160台站降水资料以及NCEP/NCAR再分析资料，分析了2004年秋季发生在中国长江以南地区的严重干旱（简称2004年长江以南秋旱）前兆和发展特征以及秋旱持续期间的东亚大气环流异常。结果表明:2004年长江以南秋旱是以8月在广西境内出现小范围干旱为前兆，9月扩展到长江以南中部地区，10月遍及整个长江以南地区而达到鼎盛的一个发展过程。2004年长江以南秋旱事件的发生、发展和鼎盛期都受到了同期东亚大气环流异常的很大影响:2004年秋季东南亚上空的整层经向水汽输送出现了显著的负异常，说明2004年秋季长江以南地区上空的整层水汽在经向上由南向北的输送减弱而从北向南的输送加强；850 hPa水汽输送的异常加强了从北向南的水汽输送，从而影响了秋旱的发展。结合2004年秋旱持续期间850 hPa 流场异常分析，2004年秋季850 hPa的流场在台湾海峡附近上空出现了一个气旋性的异常环流，它导致了西南水汽及其与越赤道气流和东南水汽的混合气流（10°N～20°N, 135°E～150°E）在向北的输送路径上发生改变，并且此混合气流进入内陆从而加强了大陆上空由北向南的干冷气流，进一步影响了秋旱的发展。通过分析850 hPa等压面上的垂直速度场发现:秋旱同期长江以南地区下沉气流异常，这种天气形势不利于降水的产生。2004年秋季长江以南地区受到了闭合高压——西太平洋副热带高压（简称西太副高）的长期控制，形成少雨的天气。除此之外，中高纬地区脊区前方和槽区的后方易于冷空气的南下输送， 这在很大程度上也促使了秋旱的发展。 相似文献
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粤北石灰岩地区是指分布在乐昌、乳源、曲江、连县、连南、阳山、英德和清新等县内的石灰岩地区。总面积6000多km2，占全省同类地型面积90％以上，该地区秋季光温资源丰富，生产潜力大，受秋季缺水的制约，不能充分利用，严重地影响了农业生产的发展。因此，我们应该重视和研究石灰岩地区的秋旱问题。l资料的选择和秋旱指标本文的秋旱是指发生在8～10月期间的干旱。发生在8月的称早秋旱，发生在9月或以后的叫晚秋旱。资料统计时数为建站以来至1995年的历年8月1日至10月对日；选择站点是乐昌、韶关、连县、阳山和英德5个台站，秋旱的指标为秋… 相似文献
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1998年我国天气气候特点 总被引：7，自引：1，他引：6
１９９８年我国天气气候有如下几个主要特点：南方部分地区出现冬春汛,夏季长江、嫩江和松花江流域发生严重洪涝,秋季降水偏少,部分地区出现秋旱;全国年平均气温普遍偏高;生成和登陆的台风异常偏少;风雹天气接近常年;青藏高原出现罕见雪灾。 相似文献
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利用甘肃省19个气象站点1960—2018年逐月平均降水量、气温等数据,应用标准化降水蒸散量指数(Standardized Preapitation Evapotranspiration Index,SPEI)、Penman-Monteith模型、小波分析等方法分析了甘肃省近58 a不同时间尺度干旱事件的时空演变特征。结果表明:月尺度干旱频率3月最高,2月最低;季尺度上秋季干旱最严重,春季次之;冬季干旱化趋势最慢,春季最快。近58 a甘肃省SPEI指数呈下降趋势,年尺度SPEI指数存在8 a、12 a、26 a的周期。干旱发生频率在年尺度和月尺度上的分布较为一致,河西走廊东段与甘南州地区频率较低,酒泉北部地区与甘肃省东、中部地区频率较高;季尺度上,春季兰州与武威南部地区频率较高,庆阳地区频率最低;夏季为白银与武威北部地区频率最高,张掖中部地区、白银北部地区以及临夏、庆阳、平凉地区最低;秋季频率最高的地区为兰州东部、定西东北部以及嘉峪关地区,最低的地区在酒泉、张掖、武威北部及平凉中部地区;冬季高值区在平凉,低值区在武威与甘南。干旱发生强度最高的地区为张掖,其次为酒泉、庆阳及白银等地区,最低的区域位于甘肃西南地区。酒泉、嘉峪关等地区干旱化程度逐年加剧;甘肃东南地区干旱速率较西北地区慢;中西部地区干旱化速率最慢,且甘南北部与武威西南部地区有湿润化趋势。 相似文献
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公主岭市近50年气候变化特征分析 总被引：1，自引：0，他引：1
本文利用公主岭市气象观测站1961-2010年50年的降水、气温、蒸发量资料,对近50年来公主岭市的气候变化进行分析,结果表明:年平均气温呈波动增加的趋势,各季气温变化与年变化趋势相同,以冬季的增暖最为明显,进入21世纪的头10年是1960年代以来最暖的10年;年降水量呈减少的趋势,其中夏季和秋季降水量与年变化趋势相同,而春季和冬季降水量则略有增加,暴雨日数增加;年蒸发量呈增加的趋势,夏季、秋季、冬季蒸发量均呈增加的趋势,只有春季蒸发量呈减少的趋势;随着夏季和秋季降水的减少,而蒸发量的增加,夏旱和秋旱将越来越明显。 相似文献
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近51年500 hPa上北极涛动的时空变化特征分析 总被引：7，自引：4，他引：3
对1951-2001年北半球500hPa高度场月、季及年平均资料分别进行EOF分析．并对EOF分析得到的第一特征向量时间系数进行功率谱分析。结果发现：北极涛动是近51年北半球500hPa高度场异常的第一特征,方差贡献率在10％～20％之间;极区中心具有明显的偏心结构,范耐冬、春季大而向高纬伸展;夏、秋季小且向极区收缩。中高纬冬季中心区范围比夏季大且系统比较集中：极地到格陵兰岛附近、西南欧洲到地中海地区、贝加尔湖到日本海以及北美洲东南部地区是500hPa高度场上环流异常的主要发生地区;北极涛动正位相时期,冬季在20世纪90年代,春季在70年代中期以前,夏季在60,70年代,秋季在80年代中后期到90年代前期;北极涛动负位相时期,冬季在50年代．春季在70年代中期以后,夏季在50,90年代,秋季在90年代后半期。另外,只有1998年相对来说为全年各月北极涛动强年,说明1998年是近51年来气候最异常的一年。 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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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
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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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The moving-window correlation analysis was applied to investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the synchronous autumn precipitation in Huaxi region, based on the daily precipitation, sea surface temperature (SST) and atmospheric circulation data from 1960 to 2012. The correlation curves of IOD and the early modulation of Huaxi region’s autumn precipitation indicated a mutational site appeared in the 1970s. During 1960 to 1979, when the IOD was in positive phase in autumn, the circulations changed from a “W” shape to an ”M” shape at 500 hPa in Asia middle-high latitude region. Cold flux got into the Sichuan province with Northwest flow, the positive anomaly of the water vapor flux transported from Western Pacific to Huaxi region strengthened, caused precipitation increase in east Huaxi region. During 1980 to 1999, when the IOD in autumn was positive phase, the atmospheric circulation presented a “W” shape at 500 hPa, the positive anomaly of the water vapor flux transported from Bay of Bengal to Huaxi region strengthened, caused precipitation ascend in west Huaxi region. In summary, the Indian Ocean changed from cold phase to warm phase since the 1970s, caused the instability of the inter-annual relationship between the IOD and the autumn rainfall in Huaxi region. 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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基于最新的GTAP8 (Global Trade Analysis Project）数据库,使用投入产出法,分析了2004年到2007年全球贸易变化下南北集团贸易隐含碳变化及对全球碳排放的影响。结果显示,随着发展中国家进出口规模扩张,全球贸易隐含碳流向的重心逐渐向发展中国家转移。2004年到2007年,发达国家高端设备制造业和服务业出口以及发展中国家资源、能源密集型行业及中低端制造业出口的趋势加强,该过程的生产转移导致全球碳排放增长4.15亿t,占研究时段全球贸易隐含碳增量的63%。未来发展中国家的出口隐含碳比重还将进一步提高。贸易变化带来的南北集团隐含碳流动变化对全球应对气候变化行动的影响日益突出,发达国家对此负有重要责任。 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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《大气和海洋科学快报》2013,(1):67
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