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中国气象科学研究院曾长期组织和从事东亚季风及其对中国天气和旱涝影响的研究。该文对中国气象科学研究院在东亚季风研究方面取得成果进行综述, 并回顾了20世纪50年代以来国内有关季风的研究活动, 也回顾了影响我国天气气候、东亚季风环流系统的提出及其后续的有关东亚和印度季风系统的相互作用, 引发中国大陆暴雨生成的水汽输送, 表达中国大陆季风活动的季风指数设计等研究结果。综述了南海夏季风爆发、梅雨开始、中国雨季开始及传播等有关研究成果; 东亚季风系统中副热带地区低频振荡纬向和经向传播特征及与赤道地区不同之处, 东亚低频振荡对El Ni?o形成及夏季东亚热带和副热带季风爆发的可能影响, 东亚热带和副热带季风低频振荡对中国天气气候的影响等有关成果; 亚洲地区大气热源的计算及其分布, 青藏高原夏季热源对东亚夏季风及降水的可能影响, 青藏高原冬季冷源对El Ni?o生成的可能影响等有关成果; 东亚季风及降水的年际变化特征, 准4年年际振荡的分析及与ENSO形成间的相互作用, 极地对东亚夏季降水的影响及东亚季风年代际变化特征等成果。综述东亚季风系统形成的可能机制, 特别是亚洲大陆—西太平洋海陆热力差异及非洲、印度半岛、中南半岛及澳大利亚陆地与周围海洋对冬夏季风形成、印度和东亚季风系统形成、南海夏季风形成作用的结果。 相似文献
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该文基于贵州省防雷安全监管模式创新的理论和实践,参照防雷相关法规、监管体系建设相关论文研究,就贵州省基层防雷监管存在的困难和突出问题开展调查研究,收集整理和分析各市(州)县局的防雷监管基础数据,结果表明:一是统筹市(州)局技术优势弥补县局短板,促进市(州)和县局资源互补;二是要强化学习培训的组织管理和成效考核,解决学用结合率不高、重视不够的问题;三是优化监管岗位、人员和权责分配,在权责法定的基础上用制度进一步予以规范;四是探索基层法律顾问制度建设,加强基层法规预算管理,解决专业人才不足、法规预算不足的困难;五是要全面加强管理和服务能力建设,在履行好法定监管职责的同时,提升专业气象服务能力,增强基层基础保障能力。 相似文献
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西太平洋副热带高压的年际变率受热带多个关键海区的海-气相互作用过程调控, 但彼此间的因果关联和影响机制尚不清楚。为揭示西太平洋副热带高压的年际变率与热带海温及大气环流异常之间的内在关联特性, 定义了三个关键海区以及赤道纬向西风区的特征指数, 并分别与西太平洋副热带高压强度、脊线指数进行了交叉小波和相干小波分析。研究发现:西太平洋副热带高压指数存在显著的2~3年和准5年的周期振荡, 20世纪八九十年代后, 由于暖池区海温及赤道纬向西风区的Hadley环流强迫加强, 致使副热带高压特征指数的2~3年周期振荡加强; 从位相关系看, 先是西太平洋副热带高压减弱南撤导致纬向西风加强, 其后影响赤道东太平洋海温升高, 同时暖水向东传, 使赤道中太平洋以及暖池区海温逐渐升高, 在Hadley环流作用下使副高加强北抬。基于上述西太平洋副热带高压的年际变率与热带海温及大气环流异常变化相关性诊断研究, 进一步探讨了造成这种相关性的影响机理和因果关联, 为揭示西太平洋副热带高压年际变率与热带海温及大气环流异常的相关性做探索研究。 相似文献
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长江中下游夏季降水异常变化与若干强迫因子的关系 总被引：24，自引：6，他引：18
首先,利用三次样条函数方法对1905～2000年长江中下游夏季降水量和太阳黑子、地球自转速率、赤道东太平洋海温和北极涛动等强迫因子序列进行年代际和年际尺度的分离,并分析了它们年代际尺度的位相变化特征.然后,使用30年滑动相关的方法,分析了长江中下游夏季降水量与上述各因子之间的相关随时间的变化.最后,利用旋转因子分析方法,对年代际及年际尺度因子的潜在结构对长江中下游夏季降水的影响进行了研究.结果表明,长江中下游夏季降水量和强迫因子序列均存在显著的年代际变化特征,它们之间的相关系数随时间变化呈现显著的阶段性, 相似文献
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利用自动气象站、多普勒雷达、FY4A、ECMWF模式、NCEP再分析资料,对2020年7月17—19日特大暴雨过程进行分析。结果表明：特大暴雨出现在安徽大别山附近和庐江两地,是中尺度气旋扰动环境下准静止的中尺度对流系统(MCS)以及MCS中准静止的涡旋状单体所产生。特大暴雨在高能量、强不稳定背景下,由中部和东部的中尺度气旋传播所致。中尺度气旋传播过程中单体不断新生、合并增强且移动缓慢,配合急流、辐合、干侵入、垂直环流等因素对组织化的MCS发展演变起到相当作用。低层切变线南侧到华南的西南急流,将水汽输送到安徽并在此有强烈辐合;高空、低空和超低空都存在急流,高低空急流耦合加剧MCS的强烈发展;地面辐合线是前期MCS的触发机制,伴随干冷空气的入侵,加大了大气的斜压性和MCS的对流不稳定;梅雨锋南北两侧都有垂直环流圈,即对流与高空急流之间通过对流加热在高空急流入口处产生热成风调整,维持梅雨锋的发展演变,强的上升下沉运动促进MCS的加强和降水的连续发生;大别山地形抬升和上游狭管效应是两地特大暴雨诱因。 相似文献
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气候监测诊断是了解气候系统变化及其成因的重要手段。经过二十多年的发展,目前国家气候中心建立了一套多时间、多空间尺度的气候系统监测诊断业务系统,并且在业务应用中不断发展和完善。同时,加强了关键异常信号及其对我国气候异常的影响机理的研究,在海温、冰雪、土壤温湿度、大气低频振动、北极涛动、季风、平流层异常等对我国气候影响的监测诊断等方面提出一些新理论、新技术和新方法,并在业务中得以应用。本文回顾了近20年来我国气候监测诊断业务的发展历程,介绍了我国气候监测诊断业务的技术现状,重点总结了近些年来在实时气候监测诊断业务中发展和应用的一些新技术和气候异常机理。 相似文献
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We quantify the vulnerability of water supply to shortage for the Colorado River Basin and basins of the High Plains and California and assess the sensitivity of their water supply system to future changes in the statistical variability of supply and demand. We do so for current conditions and future socio-economic scenarios within a probabilistic framework that incorporates the inherent uncertainties in the drivers of vulnerability. Our analysis indicates that the most sensitive basins to both current and future variability of demand and supply are the Central California and the San Joaquin-Tulare basins. Large sensitivity is also found for the Kansas basin of the High Plains. Within the Colorado River Basin, the Lower Colorado and Gila were found to be the most vulnerable and sensitive sub-basins. By accounting for future uncertainty within the above probabilistic framework, this study unveils and isolates the individual responses of a given basin to changes in the statistical properties of demand and supply and offers a valuable tool for the identification of policy strategies and adaptation measures. 相似文献
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杭州地区酸雨分布特征及影响因素 总被引：3，自引：0，他引：3
利用2009年7月至2012年6月杭州地区7个观测站的酸雨资料并结合探空及大气成分资料,分析近3年来杭州地区的酸雨变化和分布特征,研究了气象条件和大气污染物对酸雨的影响。结果表明：杭州地区近3年降水平均pH值在437~523之间,酸雨污染空间上呈现“西重东轻”的格局,降水酸度和酸雨频率均呈现小幅波动且变化趋势不明显。酸雨污染总体上夏季最轻,秋冬季最严重,春季次之。降水量与pH值和电导率的关系各站不一,其中临安、淳安、建德和富阳等地的降水pH值与降水量成正比,杭州和桐庐相关变化关系不明显。萧山比较特殊,各地降水电导率与降水量均呈反比; 在850 hPa偏北风的输送影响下, 降水酸度及电导率较高;降水pH值与最低层逆温的高度成正比,与逆温的厚度成反比,强酸雨时在降水前半段均伴随较严重的灰霾天气,逆温对降水电导率的相关关系不是很明显; 污染物SO2、NO2、PM10、PM25的浓度与降水pH值呈负相关关系, 说明近地层污染物浓度对降水酸度有重要影响。 相似文献
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根据天津市静海区18个乡镇2009—2018年逐时降水量,以及社会经济、地理地形、水利设施等数据,结合历史受灾信息,分别对静海区的暴雨致灾因子危险性、孕灾环境敏感性、承灾体易损性及防灾减灾能力进行分析,采用GIS技术和统计方法多因子叠加,综合得出静海地区暴雨灾害风险精细化评估和区划。研究发现,静海区北部区域以及南部中旺镇及其周边风险较高,而静海地区中部的风险较低;暴雨灾害高风险区主要分布在致灾因子敏感性、承灾体易损性较高而防灾减灾能力较低的静海镇和梁头镇及其周边,应加强防灾减灾设施建设。 相似文献
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在总结前人关于中国夏季雨型划分的研究成果及其存在的主要问题的基础上 ,对中国夏季雨型的划分进行了新的尝试。根据东部季风区夏季 ( 6～ 8月 )降水的客观气候规律及业务预报应用需要 ,利用经验正交分解、主成分分析、奇异值分解、聚类分析等数理统计方法 ,结合经验分析 ,对中国东部季风区 1 880年以来 1 2 0多年夏季降水进行了客观分型 ,将中国东部季风区夏季降水划分为两类四型 ,并进一步分析了各类雨型的大气环流成因。 相似文献
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利用NCEP/NCAR再分析资料,通过客观判定和追踪反气旋的方法统计分析了1948~2013年北半球冬季温带反气旋的时空分布、周期和生命史等气候特征。结果表明,北半球冬季温带反气旋主要活动在东北太平洋、北大西洋、北美落基山脉东部和加拿大、美国东部、欧洲、亚洲中部和东亚地区。太平洋和大西洋上反气旋的生成区分布较分散,于大洋西部生成,在中、东部达到成熟期,最后主要在大洋东部和大陆西岸消亡。大西洋上反气旋消亡区域的大值区从大西洋中部到欧洲西海岸呈西南—东北带状分布,而太平洋上的反气旋消亡区域的两个大值区独立分布。大陆上反气旋多生成于较高纬度和极地地区,主要向东、向东南方移动。北半球各区域反气旋数均具有显著的2~3年周期变化特征,欧亚地区则具有显著的16~18年周期的年代际变化特征。除了欧亚大陆,其他三个区域的反气旋偏强时,其运动轨迹偏北。北美地区反气旋越强,其运动的纬度范围越大;而欧亚大陆反气旋越强,其运动的纬度范围越小。生命史越长的反气旋数比例越少,只有不到10%的反气旋生命史超过一周。 相似文献
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选取2015—2018年影响华东地区的13个台风个例,分析降水极端天气指数EFI (Extreme Forecast Index)和SOT (Shift of Tails)与台风降水之间的统计关系。结果表明:EFI和SOT与降水气候百分位之间存在明显的正相关关系。EFI和SOT越大,强降水发生概率越高。随着预报时效的增加,EFI和SOT指数对暴雨和大暴雨的预报效果逐渐变差。对于短期(72 h以内的时效),EFI预报技巧优于SOT,而随着预报时效的延长,SOT的预报技巧逐渐接近并超过EFI。以TS评分最大为标准兼顾合理的预报偏差,得到两种极端天气指数不同预报时效、不同等级暴雨的预报阈值。总体而言,事件越极端,EFI和SOT的预报阈值越大,对于暴雨和大暴雨,EFI指数的预报阈值随着预报时效的延长有减小趋势,而SOT的预报阈值基本保持不变。在台风极端降水预报中,EFI和SOT可以作为EC定量降水预报的补充,有助于减少强降水的漏报,并提早发出预警信息。 相似文献
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A. V. Frolov V. V. Asmus I. V. Zemlyanov O. I. Zil’bershtein V. A. Krovotyntsev V. A. Martyshchenko E. A. Mironov 《Russian Meteorology and Hydrology》2009,34(3):148-158
In accordance with the contract of the LUKOIL Oil Company, a cooperation of the Roshydromet organizations (Planeta Research Center for Space Hydrometeorology, a main contractor, Hydrometeorological Research Center of the Russian Federation, Arctic and Antarctic Research Institute, and State Oceanographic Institute) carried out in 2008 complex studies of the hydrometeorological and ice conditions for the Filanovskii oil- and gas-field facility construction on the northwestern shelf of the Caspian Sea. Three expeditions were organized and conducted within that project: a helicopter ice research expedition (specialists from the Arctic and Antarctic Research Institute carried out a huge volume of measurements of physicomechanic properties of level, rafted and hummocked ice, and morphometric characteristics of ice piling, hummocks, and stamukhas); specialists from the State Oceanographic Institute organized a ship expedition on studying sea ground exaration formed due to impacts of ice formations (hummocks and stamukhas) using hydro-radar and echo-sounder surveys as well as a complex hydrometeorological and hydrochemical expedition with five autonomous buoy stations mounted in two months. From the moment of ice formation to the end of the expedition activity, an operational space monitoring of the northwestern Caspian Sea was carried out at the Planeta Research Center for Space Hydrometeorology. Based on the NOAA, TERRA, and AQUA satellite data, corrected and geographically fixed satellite images of the area of activity were issued with a periodicity of 6 times per day; index maps on the ice situation (twice a week) and ice situation forecasts (lead-time of 1–7 days). Besides, long-term series of satellite data on the northwestern Caspian Sea are collected and processed: their results are used for estimating seasonal and interannual variability of the drift ice and fast ice. Specialists of the Hydrometeorological Research Center of the Russian Federation completed the work on processing and analysis of library materials, research/technical reports, handbooks, expedition observational data, and on hydrodynamic and probability modeling of long-term series of hydrological, meteorological, and partly ice data. In particular, basic characteristics of the hydrological regime (sea level, currents, and waving) are calculated for the place of the oil platform location and along the pipeline routing. Tentative local specifications on the hydrometeorological regime in the Filanovskii field are worked out based on the results of the work performed. 相似文献
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On the basis of the emission data of the industrial sulphur dioxide (SO2) and observed climate fields over East Asia, the distribution of anthropogenic sulfate aerosol (SO) with seasonal variation in the troposphere is simulated and analyzed by a regional sulfur transport model, and the direct radiative effects of SO under different weather conditions are also calculated using the discrete ordinate method. The results show that the concentration of SO has significant seasonal and spatial variations resulting from the effects of SO2 emission source and precipita-tion and wind fields. Both the concentration of SO2 and its radiative forcing have the largest values in October and the lowest in July. SO causes the decrease of the radiation flux absorbed by earth-atmosphere and the cooling of air temperature by scattering more solar radiation back into space. Besides, the radiative and climatic effects of SO are related to the types and height and optical thickness, etc., of the clouds. 相似文献
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基于三维近地面闪电先导发展随机模式,通过改变先导初始电位和建筑物几何特性,分析各种情况下的侧击雷电发生概率,探讨侧击雷电产生原因及影响因素。结果发现:建筑物尖端电场畸变值是影响侧击雷电产生的重要参量,当下行先导靠近建筑物且传播位置低于建筑物的高度时,建筑侧面电场畸变值达到触发阈值,侧击雷电易产生;下行先导的初始电位以及建筑物几何特性（高度和宽度）是影响侧击雷电发生概率的重要因素,当下行先导初始电位在-9~-3 MV范围内,侧击雷电发生概率呈先增加后降低的趋势,当初始电位为-4.5 MV时,侧击雷电的发生概率达到峰值;当建筑物高度在50~150 m范围内,侧击雷电发生概率随着高度增加呈先增加后减少的趋势;当建筑物高度为100 m时,侧击雷电发生概率达到峰值;当建筑物宽度在30~70 m范围内,侧击雷电发生概率随建筑物宽度呈递减趋势;当建筑物宽度为30 m时,侧击雷电的发生概率达到峰值。 相似文献
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Characteristics of Subtropical Monsoon and Rainfall over Eastern China and Western North Pacific 
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下载免费PDF全文 Using the NCAR/NCEP (National Center for Atmospheric Research/National Centers for Environmental
Prediction) reanalysis and the NOAA Climate Prediction Center's merged analysis of precipitation (CMAP)during 1981-2000, we investigated the seasonal evolution of the southwesterly wind and associated precipitation over the eastern China-subtropical western North Pacific area and its relationship with the tropical monsoon and rainfall, and analyzed the reasons responsible for the onset and development of the wind. It was found that the persistent southwesterly wind appears over southern China and the subtropical western Pacific the earliest in early spring, and then expands southwards to the tropics and advances northward to the midlatitudes. From winter to summer, the seasonal variation of surface heating over western China and the subtropical western Pacific may result in an earlier reversal of the westward tropospheric temperature gradient over the subtropics relative to the tropics, which may contribute to the earliest beginning of the subtropical southwesterly wind. Additionally, the strengthening and eastward expanding of the trough near the
eastern Tibetan Plateau as well as the strengthening and westward moving of the western Pacific subtropical high also exert positive influences on the beginning and development of the subtropical southwesterly wind.In early summer,the northward expansion of the southwesterly wind over southern China is associated with a northward shift of the subtropical high, while the southward stretch of the southwesterly wind is associated with a southward stretch of the trough in the eastern side of the plateau. With the beginning and northward expansion of the subtropical southwesterly wind (namely southwest monsoon), convergences of the low-level air and water vapor and associated upward motion in front of the strongest southwesterly wind core also strengthen and move northward, leading to an increase in rainfall intensity and a northward shift of the rain belt. Accordingly, the subtropical rainy season occurs the earliest over southern China in spring, moves northward to the Yangtze-Huaihe River valley in early summer, and arrives in North China in mid summer.Compared with the subtropical rainy season, the tropical rainy season begins later and stays mainly over the tropics, not pronouncedly moving into the subtropics. Clearly, the Meiyu rainfall over the Yangtze-Huaihe River valley in early summer results from a northward shift of the spring rain belt over southern China,instead of a northward shift of the tropical monsoon rain belt. Before the onset of the tropical monsoon,water vapor over the subtropical monsoon region comes mainly from the coasts of the northern Indo-China Peninsula and southern China. After the onset, one branch of the water vapor flow comes from the Bay of Bengal, entering into eastern China and the subtropical western Pacific via southwestern China and the South China Sea, and another branch comes from the tropical western North Pacific, moving northwestward along the west edge of the western Pacific subtropical high and entering into the subtropics. 相似文献