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1.
高要市1961~2010年气候变化特征   总被引:2,自引:1,他引:1  
根据高要国家基本气象站观测资料,采用线性倾向估计、多项式拟合等方法,分析了高要市1961~2010年基本气候要素和高影响天气气候事件的变化特征。结果表明,高要市年平均气温以0.02℃/年的速率显著上升,以冬季升温最为明显。年降水量变化趋势不明显,但降水日数减少,强度增强。相对湿度、日照、蒸发均呈减少趋势,减少速率分别为0.14%/年、7.2 h/年和6.1 mm/年,风速则呈弱的增加趋势。高温日数以0.3 d/年的速率显著增加,低温日数以0.2 d/年的速率明显减少,年极端最低气温和年极端最高气温呈非对称性变化,年极端最低气温的升温速率远大于年极端最高气温,暴雨日数呈弱的增加趋势,雾日以0.24 d/年的速率增加,灰霾日显著增加,2006以来增加尤为明显。  相似文献   

2.
利用西安咸阳国际机场专用高速公路(以下简称西咸机场高速公路)段交通气象站及其10km范围内区(县)气象站的观测资料,以及MICAPS高空和地面资料,研究了西咸机场高速公路雾的变化特征、典型环流形势和气象影响因子。结果表明:雾主要发生在夜间至清晨,能见度越小的雾生成的时间越集中,2月、4月和10—12月出现的雾可持续较长的时间;典型雾日,500hPa陕西关中地区为一致的西北或偏西气流,850hPa陕西关中及其以南地区受弱暖脊控制且处于反气旋环流的底部,西咸机场高速公路及其周边地区近地面层有逆温形成,且风速小,湿度大;有利于雾发生的气象条件包括相对湿度≥80%、地面风速≤3m/s和地表温度与气温之差≥-3℃等,14时相对湿度、14时气温与未来时刻气温的差都与相应时刻能见度密切相关。  相似文献   

3.
冀中南连续12天大雾天气的形成及维持机制   总被引:7,自引:0,他引:7  
利用NCEP 1°×1°再分析资料、常规观测资料和加密观测资料,对2007年12月17-28日冀中南地区连续性大雾过程的天气背景和雾长时间维持的原因及热力、动力结构特征进行了分析。结果表明,大雾期间我国中高纬地区冷空气活动偏弱,500hPa受稳定的暖性宽广高压脊控制,为维持数日不散的大雾天气提供了有利的环流背景;850hPa及以下多以偏东风和偏南风为主,偏东风不仅使雾区近地层温度降低,而且还将海域水汽送至雾区;同时偏南风也为雾区源源不断地输送水汽,特别是东北风的维持有利于强浓雾的形成,这是大雾持久不消散的主要原因;低层弱辐合、正涡度区、弱水汽辐合和900hPa以上的暖脊有利于雾的稳定维持和发展;由于强冷空气的到来导致大雾消散,破坏了稳定的逆温层结。  相似文献   

4.
长三角地区11月大雾频次变化的天气气候背景   总被引:1,自引:0,他引:1  
采用1977—2006年长三角地区5个国家气候一级站的1日4次地面气象观测资料以及NCEP/NCAR相关资料,初步分析了该地区11月区域雾频次变化的天气气候背景。结果表明,长三角11月区域雾少发(多发)时,500hPa高空为较强的西北风(平直的西风),850hPa上为强西北风(弱西北、东北风),低层925hPa上偏北风分量较大且相对湿度较小(偏北风减小并出现偏东风分量且相对湿度较大),海平面气压场上长三角受强冷高压控制(位于弱高压底前部均压区内)。  相似文献   

5.
长江三峡库区大雾的变化特征分析及原因初探   总被引:2,自引:0,他引:2  
利用近54年三峡库区6个气象站的逐日雾、相对湿度和能见度的历史资料,对1954年以来三峡库区雾的气候变化特征,尤其是近几年三峡水库蓄水以后大雾的变化及其产生变化的可能原因进行了讨论。结果表明:1954~2007年三峡库区雾日数呈弱的增加趋势,而2000年后库区的雾日明显减少。相对湿度与雾日数之间存在显著的正相关关系,而相对湿度与气温呈明显的负相关关系。气温变化影响相对湿度变化,从而影响雾的发生频率是三峡库区雾变化的重要原因。2000年以后,在全球变暖大背景及城市化的共同影响下,三峡库区气温显著升高,相对湿度明显减小,是导致雾日大幅减少的直接影响因素。另外,分析还显示,无论是雾日数还是相对湿度都表现出了明显的年代际振荡特征,2000年后三峡库区相对湿度减小进而雾日减少正是受到了这种年代际背景的影响。就目前的观测表明,三峡水库蓄水的小气候效应影响小或还没有明确显现。  相似文献   

6.
利用1960—2012年江西省89个气象站逐日雾的观测资料以及高速交通气象站的能见度观测资料,采用经验正交函数(EOF)方法,分析了江西省雾日数的时空分布特征。结果表明,江西省雾日数的空间分布特征与江西的地形地貌密切相关,分布特点总体是高海拔地区或山区雾日数多,丘陵平原湖泊地区雾日数少。雾日数最多的季节为冬季,其次为秋季和春季;20世纪70年代中期至80年代中期雾日数明显偏多,21世纪以来雾日数呈明显减少的趋势。雾日数的年际变化受地形的影响较大,高海拔地区或山区雾日数变化比丘陵平原湖泊地区的要大,属于雾日数异常敏感区域;在20世纪60年代至80年代中期表现为丘陵、平原、湖泊等地区的雾日数偏少,高海拔地区或山区的雾日数偏多,80年代以后则呈相反的分布型式。  相似文献   

7.
利用NCEP再分析资料及实况资料,分析四川地区1951~2007年1月典型冷、暖年及2008年1月四川低温雨雪冰冻天气的大气环流特征,发现:东亚冬季风异常偏强(偏弱)与四川隆冬季节气温偏低多阴雨雪天气(气温偏高晴少雨雪天气)明显相关,冷年表现为500hPa极涡在亚欧地区强度显著偏南(偏强),南支低槽活跃,西伯利亚~蒙古地面冷高压偏强,四川地区850hPa气温偏低,0℃线偏南,为明显的反气旋距平风场,低层湿度增加,暖年则与之相反。   相似文献   

8.
尤媛  饶晓琴  李思腾  王继康 《气象》2023,(4):506-512
2023年1月大气环流的主要特征是:北半球极涡呈偶极型分布,东北亚低涡偏强。东亚大槽偏东,南支槽偏弱。1月全国平均降水量为8.8 mm,较常年同期(14.3 mm)偏少38%;全国平均气温为-4.4℃,较常年同期(-4.8℃)偏高0.4℃。月内气温冷暖起伏较大,中下旬出现3次冷空气过程,气温由上旬异常偏暖逆转为下旬普遍偏冷的格局,黑龙江出现极寒天气,漠河最低气温达-53℃,刷新我国最低气温纪录。13—16日出现年度首次大范围寒潮天气,具有降温剧烈、风力大、雨雪范围广等特点,新疆、陕西、山西、河南等地出现大雪或暴雪,北方地区出现首次沙尘天气过程。此外,上旬大气扩散和湿清除条件较为不利,出现持续性雾-霾天气。  相似文献   

9.
利用1961--2008年内蒙古中西部地区5—9月逐日最高气温资料和国家气候中心提供的北半球500hPa高度场(5-10网格距)资料。定义了3种不同强度的最高温度日。统计了近48年5—9月各月不同强度最高气温发生频率,进行时空特征分析。分析日最高气温日数高发期的夏季(6—8月)强日最高气温日数典型年北半球500hPa高度距平场分布特征。结果表明:近48年5—9月各月日最高气温日数高发期在夏季(6—8月);7月最多,9月最少;气候变暖使得日最高气温日数有明显增加;日最高气温日数典型偏多年和典型偏少年的北半球500hPa高度距平场在欧亚大陆出现明显相反的分布特征。  相似文献   

10.
利用1961—2022年江西74个气象站平均气温、最高气温、最低气温、降水量、相对湿度、平均风速和日照时数资料,对比分析了1991—2020年和1981—2010年新、旧气候态下气象要素差异,探讨气候平均值改变对气候影响评价和预测业务的影响。结果表明:新气候态下,江西省三类气温的年和季节平均值均上升,年降水量总体增加将弱化气温偏高、降水偏多的变化特征。年和季节平均风速距平山区减小而平原地区增大;年日照时数距平总体增加。极端高温年份减少,极端低温年份增多,其中平均气温和最低气温的极端高(低)温年发生概率的降幅(增幅)比最高气温更大。极端强降水年发生概率在赣西北、赣中大部、赣南西北部等地区夏季减少,赣南中南部地区冬季增大。全省历年极端日高温、低温和强降水事件发生站次总体减少。新、旧气候态的更替会对气候业务产生影响,如冬季气温偏冷的年份增加,偏暖的年份减少,需对冷、暖冬事件进行重新评估,夏季降水增多的变化特征减弱,将导致夏季降水预测量级和趋势发生改变。  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.
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   

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18.
<正>With the support of specialized funds for national science institutions,the Guangzhou Institute of Tropical and Marine Meteorology,China Meteorological Administration set up in October 2008 an experiment base for marine meteorology and a number of observation systems for the coastal boundary layer,air-sea flux,marine environmental elements,and basic meteorological elements at Bohe town,Maoming city,Guangdong province,in the northern part of the South China Sea.  相似文献   

19.
《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   

20.
《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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