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1.
利用揭阳市1991—2020年国家基本站汛期逐日降水量资料,运用线性倾向估计、相关系数检验、累计距平法、小波分析等方法研究揭阳市汛期极端降水事件的变化特征。结果表明:揭阳市前汛期(4—6月)出现极端降水事件较后汛期(7—9月)略偏多,但后汛期的极端降水强度明显更强。前汛期极端降水日数和降水量呈上升趋势,降水强度呈下降趋势;后汛期极端降水日数、降水量以及降水强度均呈下降趋势。前汛期极端降水强度存在准15年、6~7年、准8年的周期变化,其中准15年周期震荡最强,为第1主周期;后汛期存在准9和准17年两类尺度的周期变化,二者在整个时段表现稳定,具有全域性,其中准9年为第1主周期。  相似文献   

2.
安康市近45年汛期降水变化特征分析   总被引:1,自引:0,他引:1       下载免费PDF全文
利用安康市1969—2013年汛期(5—10月)日降水量资料,分析安康汛期降水的变化特征。结果表明:安康市汛期降水量年际变化整体呈增多趋势,线性倾向率为7.47 mm/10a,但各区县不完全一致;汛期各月降水量,5、7、8月为增多趋势,6、9、10月为减少趋势。通过Morlet小波分析,发现安康市汛期降水量1975—1985年表现为准4a的周期变化,1996—2008年表现为2~3a周期变化且显著性较高,除旬阳县外各区县在20世纪90年代中后期以后年际变化较为剧烈。安康市汛期暴雨整体呈南多北少分布,紫阳县为安康市的降水中心和暴雨中心,安康市除岚皋县外其他区县的暴雨呈增加趋势。  相似文献   

3.
通过对近51 a雅鲁藏布江中游河谷地区4个气象站逐日降水资料进行等权平均取值,采用气候倾向率和小波分析法,研究了不同时间尺度下近51 a降水变化趋势及周期特征。结果表明:研究区降水量以20世纪80年代为最少,2000年后年降水量与20世纪90年代和60年代基本持平。夏季和秋季降水量年代际变化与年降水量的变化基本一致。近51 a降水量增加趋势不显著。年降水量存在准3 a、8—11 a和30 a的周期,以准11 a周期最为突出。降水量变化以春季增长趋势最显著,可在干旱季补充土壤水分,减轻风沙化土地的发生发展。秋季和冬季增长趋势不明显,夏季降水量呈减小趋势。就季节降水变化的时间尺度和周期性而言,2007年后四季降水表现为,春季在20—30 a时间尺度上将处于偏高期,夏季在8—12 a时间尺度上将处于偏低期,秋季在8—12 a时间尺度上将处于偏低期,冬季在20—30 a时间尺度上将出现向降水偏高的过渡期。  相似文献   

4.
三穗县近46a极端气候特征研究   总被引:1,自引:0,他引:1  
该文利用三穗1961—2006年的逐日平均气温和日降水量资料通过阈值求取,并采用线性趋势分析、相关分析、小波分析[6]等方法来分析三穗极端事件发生频数的总体特征,得出如下结论:夏季温度和降水的阈值比较高,对应温度高、降水多;冬季阈值低,气候干燥,温度低、降水量相对较少;通过趋势分析,95百分位极端降水日数、暴雨日数都呈增加趋势,汛期降水极端事件则呈减少趋势,但它们的变化趋势都不明显,通过相关分析发现,极端降水日数与年降水日数相关性较好,极端降水日数可以间接反映年降水日数的多少;通过小波分析得出极端降水日数周期为9 a左右,汛期降水日数的周期在11 a左右;暴雨日数在1970年以前存在准2 a的周期,在1970年以后存在4~5 a的准周期。  相似文献   

5.
近58年柳州市汛期降水特征分析   总被引:6,自引:1,他引:5  
利用柳州市1951~2008年的月降水量资料,采用线性倾向估计和小波分析方法,分析了近58a柳州市汛期(4~9月)降水的变化特征。结果表明:近58a来柳州市汛期降水主要呈波动性变化,线性趋势变化不明显,但前汛期降水总体呈上升趋势,降水量约增加87mm;后汛期降水量总体呈下降趋势,约减少了89mm。因此,前汛期有变涝趋势,后汛期有变旱趋势。近58年柳州市汛期降水年代际变化的主要周期为20~25a,20世纪80年代以后,汛期降水存在周期10-15a的年代际变化。20世纪80年代以前,柳州市汛期降水主要的年际变化周期2~4a,以后的年际变化周期是4~8a。  相似文献   

6.
海南热带气旋降水的气候特征   总被引:2,自引:2,他引:2  
整理出海南1962-2004年的热带气旋的降水资料,我们分析了海南省热带气旋降在海南省总降水中的地位及其变化特征,结果表明:海南热带气旋降水平均占年总降水量30%,但呈每10 a 3%的显著线性下降趋势;海南热带气旋降水与年总降水相关显著,年总降水显著偏少的年份,热带气旋降水偏少;热带气旋降水显著偏多的年份,年总降水量偏多;海南热带气旋降水变化的空间特征表现为明显的一致型,时间特征表现明显的周期性:高频的年际变化周期70年代前期以前为3 a周期为主,80年代中期以后以2 a的周期为主;低频的年际变化周期80年代以前以8—9 a为主,80年代以后以准6 a为主;年代际变化则以准17 a的周期为主。  相似文献   

7.
本文利用青岛观象台1898—1983年共86年的实测降水资料,计算年度和汛期(6—9月)降水量五年滑动平均值,得出年度降水序列和汛期降水序列。再用谐波分析方法,逐次寻找出年度和汛期降水量变化的主要周期,分析历史上各旱涝时段及成因,并分别建立两个序列的曲线自回归方程,其拟合精度尚好。进而制作未来一个时段的外延趋势预报。  相似文献   

8.
丽水汛期降水多时间尺度演变特征   总被引:1,自引:0,他引:1  
根据1953—2008年丽水汛期逐月降水量资料,在利用趋势分析和Morlet连续小波变化对汛期降水时频变化特征进行分析的基础上,利用功率谱及Mann-Kendall检验等方法对丽水汛期降水的周期性特征及突变性进行检验。结果表明:20世纪90年代前,汛期旱涝交替周期为16~20a,90年代后,交替周期缩短为4~6a。近56a来,丽水汛期总降水量呈下降趋势,5月和9月降水量减少较显著,但夏季降水量则有所增加,其中以8月最为明显;丽水汛期降水量存在不同尺度的周期分量,并且各周期强度有所不同,其中5a和18a的周期振荡通过功率谱检验。Mann-Kendall检验显示丽水汛期降水在20世纪80年代减少最为显著,1962年是降水减少的突变点。  相似文献   

9.
利用佛山市南海区1961—2010年逐月降水量资料,采用趋势性分析、Morlet小波分析和Mann-Kendall法进行气候变化趋势和突变分析。结果表明:近50年南海区汛期(前、后汛期)降水总量呈上升趋势。20世纪90年代到2005年后汛期降水增加明显,而总汛期降水量在20世纪90年代以来偏多。20世纪80年代到90年代初期汛期降水量下降最为明显。汛期(前、后汛期)降水量偏少集中在20世纪80年代中期到90年代前期,而总汛期和后汛期在20世纪60年代前期和20世纪90年代中期到2005年降水偏多。汛期存在准2、准4和7~8年尺度的周期;前汛期存在3~4、准2和准4年时间尺度的周期振荡;后汛期存在3~4、准2和7~8年周期。突变检测确定1992年为汛期和后汛期降水量的突变年份。  相似文献   

10.
利用汤阴县1964-2008年45 a降水资料,探讨汛期降水量和年降水量的变化趋势,并计算出各个时段的概率分布模型.结果表明:汤阴县年平均降水量呈增长趋势,约呈22 a的周期振荡,上世纪70年代以来汛期降水量与年降水量波动显著;汛期降水量和年降水量均服从正态分布.  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.
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   

13.
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   

14.
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   

15.
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   

16.
《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   

17.
《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   

18.
19.
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   

20.
Editorial          下载免费PDF全文
As we will soon celebrate the 90th anniversary of the founding of the Chinese Meteorological Society (CMS),Acta Meteorologica Sinica (AMS),which was originally named as Bulletin of the Chinese Meteorological Society,has gone through 89 years of development and excitement since her first issue in July 1925.According to archived documents (CMS Editorial Committee,1925),AMS was founded to report the research findings of Chinese meteorologists,record their recommendations for improving meteorological services,and share their common meteorological interests in order to promote the growth of AMS such that more members could be inspired to conduct atmospheric research and meteorological knowledge would be better disseminated to and benefit the general public.By upholding and carrying forward this purpose,AMS has published many highly valuable scientific papers.Some could be treated as classical articles,which have produced important influences on both domestic and international meteorological communities and the related fields.  相似文献   

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