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1.
利用寿县国家气候观象台开路式甲烷气体分析仪的观测数据，分析了淮河流域稻麦轮作农田不同生育期甲烷通量变化特征及其影响因素。结果表明：淮河流域甲烷通量一年中呈单峰型分布，峰值出现在夏季。甲烷通量日变化呈单峰型分布，峰值出现在午后，白天高于夜间。水稻生育期甲烷通量明显高于小麦生育期；小麦出苗期甲烷通量最小，成熟期最大，达到0.14 μg〖DK〗·m-2 〖DK〗·s-1；水稻拔节期甲烷通量最大，达到3.02 μg〖DK〗·m-2 〖DK〗·s-1，成熟期最小，为0.12 μg〖DK〗·m-2 〖DK〗·s-1。作物生物量对甲烷通量影响明显，水稻和小麦收割前后24 h甲烷通量降幅达到50%和30%。甲烷通量与降水、相对湿度、水汽压、土壤温度、气温均呈显著的正相关关系。降水量越大，湿度越大，温度越高，甲烷通量就越大。 相似文献
2.
利用成都地区温江、简阳两个酸雨观测站2006—2017年的历史酸雨观测资料，结合主要大气污染物浓度数据以及降水量、风等地面气象要素，分析成都地区的酸雨变化特征及趋势。研究结果表明：温江站多年平均pH值为4.74，酸雨频率为51.6%，简阳站多年平均pH值为5.64，酸雨频率为27.2%，酸雨频率在地理区域上分布呈现不均一性；降水pH值和电导率(K)季节变化特征显著，降水pH值夏季最高，冬季最低，而降水K值则相反，夏季最小，冬季最大；近年来酸雨年变化有年平均pH值上升、酸雨频率下降和强度减弱趋势特征，年平均K值减小规律明显：温江K值以每年约3.5 μS〖DK〗·cm-1〖DK〗·a-1的速率下降，简阳以每年约3.7 μS〖DK〗·cm-1〖DK〗·a-1的速率下降；降水pH值与大气污染物SO2、NO2的负相关较为明显，相关系数为-0.488，硫氧化物对酸雨污染贡献逐渐减小；降水K值和大气主要污染物有较强的正相关，相关系数为0.657，与PM10、PM2.5相关性好于与SO2、NO2，近地层大气污染颗粒物浓度对降水K值影响较大；降水pH值与降水量级的变化不明显,但降水量越大其K值越小，且随平均风速的增大降水pH值相对偏大而K值偏小。 相似文献
3.
基于大别山区35个气象观测站1971—2020年逐日气象资料、DEM数据，采用气候统计分析、逐步订正法和趋势面插值等方法，对茶叶光合生产潜力（YQ）、光温生产潜力（YT）和气候生产潜力（YW）时空变化特征、气候资源贡献率及其对气候变化的响应进行了分析。结果表明：大别山区茶叶YQ和YW呈下降趋势，降幅分别为0.58和0.05 t〖DK〗·hm-2〖DK〗·(10a)-1，YT呈增加趋势，增幅为0.36 t〖DK〗·hm-2〖DK〗·(10a)-1；空间分布上，YQ随纬度的增加而增加，YT随纬度和海拔的增加而减少，YW随纬度的增加而减少、随海拔的增加而增加；太阳辐射、温度和降水对YW的贡献率分别为26%、48%、26%，温度的促进作用与太阳辐射和降水的抑制作用相互抵消，致使YW总体呈动态平衡趋势；气候变化背景下，大别山区北部地区较南部地区YQ下降趋势更加明显，南部地区较北部地区YT增加趋势更加明显，YW在低海拔地区呈增加趋势而在高海拔地区呈下降趋势。研究结果可为大别山区茶叶产业充分利用气候资源、高效趋利避害、合理优化产业布局提供科学依据。 相似文献
4.
山东夏季两次切变线暴雨过程对比分析 总被引：3，自引：0，他引：3
利用常规观测资料、卫星云图、多普勒天气雷达和NCEP1°×1°再分析资料,对2012年7月30日和2013年7月9日山东出现的两次区域性暴雨进行了对比分析,结果表明：两次850 hPa切变线造成的暴雨,线状MCS(Mesoscale Convective System)组织化程度高,地面辐合线触发了暴雨的发生。不同的是:①“7〖DK〗·30”暴雨500 hPa影响系统为阶梯槽,副高位于朝鲜半岛以东;“7〖DK〗·9”暴雨为典型的东高西低形势,副高控制华东沿海;②“7〖DK〗·30”暴雨受一股较强的东南气流作用,将东海及西太平洋水汽输送到暴雨区,925 hPa水汽通量散度和最强上升速度较“7〖DK〗·9”暴雨分别大-10 g〖DK〗·hPa-1〖DK〗·cm-2〖DK〗·s-1和-0.2 Pa〖DK〗·s-1,“7〖DK〗·9”暴雨由低空西南急流将南海的水汽输送到暴雨区,925 hPa水汽通量和比湿较“7〖DK〗·30”暴雨分别大2~4 g〖DK〗·cm-1〖DK〗·hPa-1〖DK〗·s-1和2 g〖DK〗·kg-1;③两次暴雨过程MCS发生发展过程、形成方式和成熟期组织结构存在显著差异,“7〖DK〗·30”暴雨是对流单体独立发展逐渐合并成β中尺度,最终形成α中尺度对流系统,“7〖DK〗·9”暴雨为多个对流单体合并为β中尺度系统。通过分析得出,切变线暴雨触发机制应着眼于地面辐合线的形成和加强以及冷空气侵入引起的锋生。 相似文献
5.
1961-2009年三江源地区气候变化特征分析 总被引：2，自引：0，他引：2
利用三江源地区18个气象台站1961—2009年气温、年最高气温、年最低气温、降水量、降水日数等资料,分析了该地区年最高气温、年最低气温、降水量、降水日数等气候要素的变化趋势。研究表明:近49年来三江源年平均气温、年平均最高气温、年平均最低气温均在升高,升高速率平均最低气温明显大于平均气温和平均最高气温,年平均气温的升高主要是由最低平均气温升高引起的;三江源年和四季降水量均呈增多趋势,冬、春季降水量增幅最明显,年降水量变化的空间分布北部增多而东南部减少,年降水量除20世纪70年代—21世纪初均呈增加趋势;年和冬、春季≥0.1mm降水日数增加,而夏秋季降水日数减少;年和冬、夏、秋季潜在蒸散量呈显著性增加趋势,春季变化则不明显;年和四季平均风速均呈显著下降趋势;年和四季日照时数变化不显著。 相似文献
6.
新疆吉木萨尔县45年气候变化特征分析 总被引：6，自引：1，他引：6
利用吉木萨尔县1961-2005年历年日平均气温、最高（低）气温、降水量、日照时数、风速等资料，分析该县45年年际、年代际、四季及近10年的气候变化特征。得出：（1）吉木萨尔县45年全年及四季气温变化均呈上升趋势，尤其冬季增温最明显，为0．62℃／10年；且近10年是45年中最暖的时期。（2）45年来平均月最高气温变化不大；而月平均最低气温增温明显，尤其近10年平均月最低气温达45年中的最高。（3）45年全年降水量变化呈增湿趋势，变化倾向率为8．19mm／10年，其中：冬季和夏季降水量呈逐渐增多趋势；而春季和秋季平均降水量则呈缓慢减少的趋势。不同年代际全年和夏季降水量均以1990年代最多，1970年代最少。近10年的年降水量也呈增湿趋势，其中冬季降水量为45年中最多时期；秋季降水量为45年中最少时期。（4）45年中任何时段的日照时数和平均风速变化均呈减少（小）趋势。对当地生态环境的改善和农业经济发展等都有十分重要的意义。 相似文献
7.
黄河断流事件的发生是人为因素与自然因素——人类生产活动用水量急增与天然径流量骤减共同作用的结果。自然因素作为天然背景具有不可低估的作用，在引起黄河断流的所有气候因子中，降水减少的贡献最显著，其次是蒸发增加的影响。当代黄河断流事件的发生和持续加重似与El Nin〖DD(Y-1.5mm〗~〖DD)〗o事件的频繁发生及其持续强劲有某种关联，本文即通过对黄河径流及其流域内的降水、蒸发、气温等方面气候因素与El Nin〖DD(Y-1.5mm〗~〖DD)〗o事件的遥相关作用进行分析，寻求导致黄河径流减少的可能原因，从而揭示黄河断流与El Nin〖DD(Y-1.5mm〗~〖DD)〗o事件的联系。结果表明，通常情况下，El Nin〖DD(Y-1.5mm〗~〖DD)〗o事件发生时，黄河流域年平均降水量减少10.35%,可造成黄河年径流减少12.95% (含有来自蒸发增加所造成的影响)，约相当于减少73.45×108 m3的水量。随El Nin〖DD(Y-1.5mm〗~〖DD)〗o事件强度的加深，降水量与径流量均迅速递减，强El Nin〖DD(Y-1.5mm〗~〖DD)〗o事件黄河流域年平均降水量减少20.43%，黄河径流量减少25.59%（147.17×108m3）；1997年断流最严重时降水减少30.62%,径流骤减40.27%（229.96×108 m3 ）。可见El Nin〖DD(Y-1.5mm〗~〖DD)〗o事件对黄河断流所造成的影响是相当深刻的。 相似文献
8.
利用多普勒天气雷达VWP资料,结合探空资料和降水实况,对4次大暴雨降水过程雷达径向速度和超低空西南急流特征进行了分析。4次强降水过程有3次属于低槽冷锋类,1次属于切变线类,K值较大,850 hPa与500 hPa温差较小,较弱的垂直风切变,中低层具有充沛水汽。低层具有相似的流场结构,径向速度上零速度线表现为“S”型,即暖平流结构。上游超低空风速≥10 m〖DK〗·s-1,上下游雷达之间出现≥5 m〖DK〗·s-1的风速差之后,两部雷达之间出现小时雨量30 mm以上的强降水;上游超低空急流达到12 m〖DK〗·s-1以上,并且上下游超低空风速差超过15 m〖DK〗·s-1,降水强度进一步加强并维持。超低空急流的建立与维持,同时上下游雷达之间的超低空强辐合,为降水风暴的发展与维持提供了能量、水汽与动力条件,对强降水的形成与持续具有重要作用。 相似文献
9.
风灾对新疆农牧业生产造成极大危害。本研究以风灾造成的倒塌房屋数、倒塌棚圈数、死亡人数、农作物受灾面积、损坏大棚数、牲畜死亡数作为6大灾情要素，运用比值权重和无量纲化线性求和方法构建表达风灾事件强弱的灾损指数，并采用百分位数法将风灾事件的强度划分为一般（1级）、较重（2级）、严重（3级）、特重（4级）4个等级。根据灾损指数和灾害等级，研究新疆风灾的时空变化特征。结果表明：新疆风灾集中于4—5月，南疆多于北疆，吐鲁番盆地和塔里木盆地北部是风灾的多发区和重发区；近30年风灾年出现次数呈显著的线性增加趋势，年灾损指数没有表现出线性增加或减少的变化趋势，其中1～4级风灾的年际变化具有明显的差异性；引发1～4级风灾的极大风速阈值分别为12.9、13.7、14.1、15.0 m〖DK〗·s-1；超过12.9 m〖DK〗·s-1极大风速出现日数逐年增多，加之农牧业生产快速发展，导致风灾年出现次数不断增加。 相似文献
10.
采用1953—2010年南岳高山站逐日气象资料,运用线性回归、突变分析和小波分析方法,对该站平均风速、气温和降水的气候变化特征进行了分析,并对与平均风速变化密切相关的气温和降水进行了年际变化特征比较.结果表明:1)年和四季平均风速均呈明显减小趋势,在20世纪90年代前后风速有由大到小的突变,年平均风速存在显著的准2 a和准4 a周期;2)年平均气温、最低气温、最高气温均呈明显升高趋势,气温存在显著的准2 a和准4 a周期,且于20世纪90年代中期前后气温有由偏低向偏高的突变;3)年降水量呈下降趋势,存在显著的准2 a和准3 a周期;4)风速与平均气温、最高气温和最低气温呈负相关关系,均通过0.01显著性检验,风速与降水的相关性没有通过显著性检验,但风速与降水的变化趋势在20世纪60年代中后期、70年代中期到21世纪初有较好的反相位变化. 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.
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
16.
《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
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<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
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