2017-11-15安徽颍上团雾天气特征分析及气象服务探讨     

梁莉  田华  李蔼恂  张楷翊  周建平  马学款  吕梦瑶  赵鲁强 《气象与环境科学》2020,43(1):9-17

团雾是一种严重威胁公路交通安全的恶劣天气,因其具有较强的局地性、突发性特点,也是目前公路交通气象预报服务的难点之一。针对2017年11月15日发生在安徽阜阳滁新高速颍上段的团雾交通事故,利用颍上交通气象站、焦岗湖交通气象站与颍上气象站的逐10 min气温、相对湿度、风速、能见度监测数据,结合欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts)的分析场资料,分析了安徽颍上团雾交通事故发生地的局地环境特征和当日的天气特征及成因,探讨了高速公路团雾预报服务的不足和未来工作展望,为进一步做好团雾天气交通气象服务提供借鉴和参考。主要结论如下:此次团雾发生在辐射雾的天气形势背景下,夜间辐射降温幅度达5℃以上,为团雾发生提供了低温条件;团雾发生地地势低洼且临近水系,水汽输送通道流畅,水汽充足,黎明后底层空气湿度维持在85%以上,是团雾发生的诱因之一;日出后风力保持静风状态,空气流动性差,造成近地面层水汽聚集,是团雾发生的重要原因。  相似文献   

国庆60周年庆祝活动气象服务满意度评估   总被引：2，自引：1，他引：1  

潘进军  段欲晓  马晓青  李如清  许国宇 《气象》2011,37(11):1409-1414

中华人民共和国成立60周年庆祝活动是一项重要的大型活动,做好该活动的气象服务保障具有重要意义。为了不断地提高气象服务水平,有必要通过开展气象服务满意度评估等工作,深入了解重大活动气象服务用户的需求和满意度情况,从用户角度对重大活动气象服务进行评价并提出改进措施。该研究采用国际通用的满意度调查评估方法,分析决策用户对气象部门服务的针对性、产品质量属性、服务方式、现场服务能力、预警服务、应急保障服务和总体气象服务效益等认知度。结果显示,决策服务用户满意度指数平均为97%,其中,对高影响天气预报服务的满意度指数为93%,与其期望度之间还存在一定的差距（6.7%）。研究分析表明,国庆60周年庆祝活动气象服务以较高水平满足了决策用户群的需求,同时,在高影响天气预报预警等方面还有待进一步提高服务水平,并给出有针对性的对策建议。通过开展该评估工作,有助于气象部门深入细致地了解气象服务效果及其差距,为今后做好重大活动气象服务积累经验。  相似文献   

青藏高原红原站平流层下部重力波观测特征分析   总被引：2，自引：0，他引：2  

张灵杰  林永辉 《气象科技》2011,39(6):768-771

利用位处青藏高原的红原探空站2008年5月垂直高分辨率的无线电探空资料分析了其上空下平流层(19～26 km)重力波的波动特性.结果表明:重力波的垂直波长主要集中在2～4 km之间,平均值约为2.9 km;水平波长主要集中在100～600 km之间,平均值约为311 km;固有频率主要集中在1.5f～3.5f(f为科氏...  相似文献   

北太平洋副热带西部模态水异常与东亚中高纬度大气环流关系的一些新认识     

常蕊  张庆云  李荣凤 《气象学报》2011,69(4):655-663

根据1958-2001年SODA(Si mple Ocean Data Assi milation)海洋同化资料和NCAR/NCEP再分析资料,利用等密度面P-矢量计算法,分析探讨了北太平洋副热带西部模态水(简称STMW)季节演变和年际变化与前期东亚-北太平洋中高纬度大气环流异常的关系。分析指出:(1)STMW的体积具有显著的季节变化特征:4月体积最大、强度最强,夏秋逐渐减弱,12月体积最小、强度最弱。研究进一步指出,STMW体积的季节变化与西北太平洋中纬度地区的海表风应力及净热通量的季节演变过程紧密联系在一起,它在一定程度上反映了西北太平洋中纬度大气环流季节性演变的特征。(2)年际尺度上,5-7月STMW指数具有显著的3年左右的振荡周期,其年际变化不仅与海洋自身动力过程有关,还与前冬亚洲-太平洋中高纬度大气环流异常引起STMW形成区风应力动力混合及海表净热通量等因子异常有关:冬季东亚季风环流偏强(弱),STMW形成区洋面风应力的动力混合作用及海表热力蒸发加强(减弱),使得海洋对流混合加强(减弱),进而加强(抑制)了混合均匀的低位涡水体进入温跃层,随着季节演变,造成5-7月STMW强度加强(减弱)。5-7月S...  相似文献   

Changes of Accumulated Temperature, Growing Season and Precipitation in the North China Plain from 1961 to 2009          下载免费PDF全文

SONG Yanling  ZHAO Yanxi  WANG Chunyi 《Acta Meteorologica Sinica》2011,25(4):534-543

Using the high-quality observed meteorological data, changes of the thermal conditions and precipitation over the North China Plain from 1961 to 2009 were examined. Trends of accumulated temperature and negative temperature, growing season duration, as well as seasonal and annual rainfalls at 48 stations were analyzed. The results show that the accumulated temperature increased significantly by 348.5℃ day due to global warming during 1961-2009 while the absolute accumulated negative temperature decreased apparently by 175.3℃ day. The start of growing season displayed a significant negative trend of -14.3 days during 1961- 2009, but the end of growing season delayed insignificantly by 6.7 days. As a result, the length of growing season increased by 21.0 days. The annual and autumn rainfalls decreased slightly while summer rainfall and summer rainy days decreased significantly. In contrast, spring rainfall increased slightly without significant trends. All the results indicate that the thermal conditions were improved to benefit the crop growth over the North China Plain during 1961-2009, and the decreasing annual and summer rainfalls had no direct negative impact on the crop growth. But the decreasing summer rainfall was likely to influence the water resources in North China, especially the underground water, reservoir water, as well as river runoff, which would have influenced the irrigation of agriculture.  相似文献   

Snow/Rainfall Anomaly in Winter of Northern China and Associated Atmospheric Circulation and Aerosol Distribution Features          下载免费PDF全文

LI Duo  WANG Jizhi  LI Zechun  LIU Hua 《Acta Meteorologica Sinica》2011,25(6):783-796

Based on the NCEP/NCAR reanalysis data,China station precipitation data from 1960 to 2008,and aerosol optical depth (AOD) data in northern China from 1980 to 2004,this paper investigates the variability of winter snow/rainfall in northern China and the associated atmospheric circulation and aerosol distribution characteristics by using composite analysis.The results show that winter precipitation in northern China has been generally increasing since the 1960s.Among the winters of 1990-2008,the years with more rain/snow (MRSYs) are 1998,2003,and 2006,while the years with less rain/snow (LRSYs) are 2005,1997,and 2001.Composite analysis finds that the main differences of atmospheric circulation in East Asia between MRSYs and LRSYs are as follows.1) In MRSYs,strong low-level cold air over the northern polar region and Taymyr Peninsula migrates southward to northern China (Northwest,North,and Northeast China),establishing a channel favoring continuous southward transport of cold air.In LRSYs,however,this cold air channel does not exist.2) In MRSYs,the frontal zone and westerlies are over North China,and the low-level geopotential height field from eastern China to West Pacific exhibits an "east high,west low" pattern,which is conducive to easterly and southerly airflows moving northward along 110 E.In LRSYs,the 500-hPa prevailing westerly winds stay far away from China and the low-level southeasterlies move to higher latitudes,which are disadvantageous to the development of precipitation in northern China.3) In MRSYs,large-scale upward motions combined with local-scale updrafts develop into strong slanted climbing airflows,forming a vertical circulation that favors the generation of heavy snows in eastern China.In LRSYs,the vertical circulation moves eastward into the Pacific Ocean.Furthermore,the correlation analysis on AOD and winter precipitation during the period 1980-2004 in northern China reveals that AOD differs significantly between MRSYs and LRSYs and the annual variation of winter rain/snow is positively correlated to the annual variation of AOD with a correlation coefficient of 0.415 at the 0.001 significance level.  相似文献   

基于高分辨率高程数据统计分析新一代天气雷达组网的地形遮挡影响   总被引：1，自引：0，他引：1  

柳云雷  李昌兴  张乐坚  文浩  王曙东 《气象学报》2020,78(4):705-720

新一代天气雷达由于受到地形限制产生波束遮挡导致波束能量衰减,从而造成雷达探测回波强度偏弱、雷达定量估测降水结果失真,因此对于雷达波束遮挡情况的统计和分析是一项重要的基础研究工作。利用SRTM （Shuttle Radar Topography Mission）数字高程数据对中国目前业务运行的212部新一代天气雷达波束遮挡情况进行模拟计算分析。计算结果包括雷达单站遮蔽角、VCP21模式0.5°、1.5°、2.4°、3.4°、4.3°仰角波束遮挡率、混合扫描及分区混合扫描波束遮挡率、雷达单站探测范围覆盖情况;计算并绘制全国天气雷达组网遮挡率拼图,统计全国天气雷达组网遮挡情况;利用2019年8月广东省11部天气雷达基数据对比验证单站及组网遮挡计算结果。结果表明雷达组网探测面积覆盖率超过70%,整体覆盖效果较好,遮挡计算结果与实际数据对比验证结果高度一致,对雷达数据订正、降水估测等产品具有正贡献。   相似文献   

山东省设施农业生产季连阴天时空演变特征及其影响          下载免费PDF全文

李文科  杨霏云  王娜  陈辰 《山东气象》2020,40(3):136-142

利用山东省59个国家级气象观测站1961—2018年逐日日照时数及32个设施农业小气候观测站2008—2018年逐日气温观测资料,采用线性回归法、Mann-Kendall突变检验法及反距离权重插值法等分析了设施农业生产季连阴天时空分布和变化规律及其对设施内气温条件的影响。结果表明,时间上,过去58 a山东省连阴天年总发生次数和总连阴天数分别以1.7次·a-1和6.5 d·a-1的趋势增加,且年总发生次数在1999年发生突变;空间上,过去58 a连阴天总发生次数和总连阴天数均呈“东北—西南”向增多分布,聊城和德州地区的增加较其他区域更为明显,单站年发生次数和连阴天数增加超过0.06次·a-1和0.2 d·a-1,且变化趋势在聊城等15个和13个站点通过显著性水平为0.05的显著性检验;随着连阴天数增加,设施内气温降温幅度会增大;相同连阴天数时,平均气温和最低气温降幅春秋季大于冬季,分析其原因可能是春秋季基础温度高于冬季,从而更容易引起温度的剧烈变化所导致。研究结果可为有关部门研究设施农业种植布局和指导设施农业生产及防灾减灾提供理论支持。  相似文献   

Asymmetric Ridge–Furrow and Film Cover Improves Plant Morphological Traits and Light Utilization in Rain-Fed Maize     

Wanlin Dong  Hang Yu  Lizhen Zhang  Ruonan Wang  Qi Wang  Qingwu Xue  Zhihua Pan  Zhigang Sun  Xuebiao Pan 《Acta Meteorologica Sinica》2018,32(5):829-838

Light is one of the most important natural resources for plant growth. Light interception (LI) and use efficiency (LUE) are often affected by the structure of canopy caused by growing pattern and agronomy managements. Agronomy practices, such as the ridge–furrow system and plastic film cover, might affect the leaf morphology and then light transmission within the canopy, thus change light extinction coefficient (k), and LI and LUE. The objective of this study is to quantify LI and LUE in rain-fed maize (Zea Mays L.), a major cropping system in Northeast China, under different combinations of ridge–furrow and film covering ratios. The tested ridge–furrow system (DRF: “double ridges and furrows”) was asymmetric and alternated with wide ridge (0.70 m in width and 0.15 m in height), narrow furrow (0.10 m), narrow ridge (0.40 m in width and 0.20 m in height), and narrow furrow (0.10 m). Field experiments were conducted in 2013 and 2014 in Jilin Province, Northeast China. Four treatments were tested: no ridges and plastic film cover (control, NRF), ridges without film cover (DRF₀), ridges with 58% film cover (DRF₅₈), and ridges with 100% film cover (DRF₁₀₀). DRF₀ significantly increased LI by 9% compared with NRF, while film cover showed a marginal improvement. Specific leaf area in DRF experiments with film cover was significantly lower than in NRF, and leaf angle was 16% higher than in NRF, resulting in a 4% reduction in k. LUE of maize was not increased by DRF₀, but was significantly enhanced by covering film in other DRF experiments, especially by 22% in DRF₁₀₀. The increase of LUE by film cover was due to a greater biomass production and a lower assimilation portioning to vegetative organs, which caused a higher harvest index. The results could help farmers to optimize maize managements, especially in the region with decreased solar radiation under climate change.  相似文献   

西南地区短时强降水的气候特征分析   总被引：5，自引：2，他引：3  

毛冬艳  曹艳察  朱文剑  田付友  郝丽萍  康岚  张涛 《气象》2018,44(8):1042-1050

利用国家级地面气象站逐小时和日降水数据集资料,对西南地区短时强降水的气候特征进行了分析,并对近30年来强短时强降水和强暴雨的变化趋势进行了分析。结果表明:西南地区短时强降水主要集中在4-10月;三个高发区分别位于贵州东南部、四川盆地西南部和云南东南部,年均发生次数约5～6次;强度一般为20～30 mm·h~(-1),其中贵州30 mm·h~(-1)以上的小时降水强度所占比例最高,四川盆地西部边缘地区小时降水最强,超过80 mm·h~(-1),极端小时降水达123.1 mm·h~(-1);短时强降水具有明显的夜发性,02时左右为发生频次的峰值时段。从近30年西南地区超过第90百分位的强短时强降水与强暴雨的长期变化趋势来看,强短时强降水呈现频次增加、强度增强的变化趋势,强暴雨则变化不明显。  相似文献