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1.
利用自动气象站逐小时地面观测资料,采用客观检验方法对北京市气象局快速更新循环预报 (BJ-RUC) 系统在2008—2010年5—9月的预报结果进行检验,初步评估了BJ-RUC系统对地面气象要素的业务预报性能。结果表明:BJ-RUC系统对地面气象要素预报与实况的变化趋势有很好的一致性。其中,2 m温度预报整体偏高,误差范围为-1.5~1.5℃,早上和傍晚偏大,正午偏小;2 m相对湿度的预报整体偏低,误差为-25%~0,白天偏大,夜间偏小;10 m风速预报明显偏大,午后尤为显著,误差为0.6~1.2 m·s-1;6 h累积降水的晴雨预报效果较好,TS评分可达到0.4。系统在初始起报时次的稳定性较差,从第3个起报时次开始逐渐稳定,但预报误差随着预报时效的增长逐渐增大,12 h内的预报误差较小,预报结果较可靠,在短时临近预报中具有参考价值。 相似文献
2.
利用BJ-RUCV2.0数值模拟资料、呼和浩特站观测资料,借助2013年7月14—15日呼和浩特地区暴雨过程,对比了数值和观测两类探空资料的参量差异,分析了数值探空资料的预报性能,结果表明:(1)就露点温度预报而言,提前12h起报的数值探空预报效果更好,但每个起报时刻的数值资料都对整层大气预报略偏湿;(2)提前12h起报的数值探空资料所反映的逆温层位置和厚度最接近实况资料,对温度预报效果最好;(3)与观测探空资料相比,数值探空资料的不稳定能量偏强,这将导致模拟降水出现时间比实况要提前;(4)在对短时临近预报有指示意义的12h预报时效内,CAPE值08时起报的误差较小,K指数20时起报的预报误差较小。 相似文献
3.
用探空资料检验中尺度数值模式对强对流天气的诊断分析能力 总被引：8，自引：2，他引：8
提高对流天气临近预报准确率的关键问题之一是了解大气的垂直稳定度和垂直风切变。中尺度数值模式产品提供了高时空分辨率的大气稳定度和垂直风切变信息，需要首先检验其精度才能进一步考虑其在对流天气预报中的应用。利用北京加密探空资料检验北京市气象局3km分辨率的MM5模式结果，对强对流天气的背景参数包括温湿风垂直廓线、对流有效位能CAPE和垂直风切变进行模式分析和预报与探空对比检验。结果表明：模式模拟的各种大气廓线中，风廓线和温度廓线都具有一定的参考价值，与实况有较好的一致性，但在廓线出现转折的地方，如：逆温层和风向转折时，模式预报较差。露点（湿度）廓线的预报误差较大，不能反映出真实水汽场的分布。因此，模式预报的深层（地面至500hPa）垂直风切变与探空具有较好的一致性，而模式给出的对流有效位能CAPE由于露点预报结果不理想，其值与实际偏差较大。因此模式输出的对流有效位能CAPE必须经过适当订正才能用于诊断强对流天气发生的可能性。 相似文献
4.
以北京市观象台2010年8月、2011年8月每日3次 (08:00, 14:00, 20:00,北京时,下同) L波段探空秒间隔数据为实况,对BJ-RUC系统 (rapid updated cycle system for the Beijing area) 分析和预报边界层性能进行了初步评估。结果表明:BJ-RUC系统对北京地区夏季白天边界层的细致特征具有较好的预报能力,但也存在明显的系统性误差。08:00边界层偏冷; 14:00和20:00 1 km以下的边界层则显著偏暖, 边界层内明显偏湿。整体上模式对边界层内温度、湿度的预报误差均高于自由大气。该系统对北京地区边界层内早晨 (08:00) 从夜间山风向白天谷风环流过渡、午后 (14:00) 到日落后 (20:00)1500 m以下盛行西南偏南气流的日变化特征具有较强的预报能力。系统预报的14:00边界层顶高度与评估时段内实际对流边界层高度的变化趋势一致。但预报的对流边界层顶偏高,这与BJ-RUC系统采用YSU边界层参数化方案的垂直混合更强有关。 相似文献
5.
使用2007、2008年5～9月北京南郊观象台的微波辐射计探测的温湿度数据和风廓线仪探测的水平风数据构造特种探空资料,将其与常规探空进行统计和对比分析,探讨了它们定性和定量应用的可靠性.结果表明,特种探空的各要素与常规探空具有较一致的变化趋势,定性分析使用时可有效弥补常规探空时间分辨率低的不足.但是,在定量使用过程中,对不同要素需区别对待:(1)特种探空的温度和经向风、纬向风的一致性好、误差较小,具有较好的定量使用价值;由于微波辐射计探测的相对湿度误差较大,造成特种探空的露点温度与常规探空的一致性较差、偏大明显;定量使用时需要订正.(2)不同时次和不同高度各要素的表现不同,08时(北京时间,下同)和20时的一致性好于02时和14时,这可能与样本数的差异和要素的日变化特征等因素有关;露点温度和纬向风的平均误差随高度增加明显增大,温度和经向风的平均误差随高度增加变化不大.(3)由特种探空得到的热力、动力稳定度参量,除粗理查逊数外,其他参量与常规探空计算得到的参量具有较一致的变化趋势,在定性使用上是有价值的.在定量使用时,需要视参量包含的温度、湿度、风等基本要素的误差程度而定.其中,与湿度相关的参量,如CAPE(对流有效位能)、Δθse(500 hPa与850 hPa的假相当位温θse之差)、K指数、湿度垂直梯度和温度露点差等参量存在不同程度的误差,而仅与温度廓线、低空风廓线相关的参量,如垂直温度梯度、0℃和-20℃层高度、低空垂直风切变等参量的绝对误差很小,具有很好的定量使用价值. 相似文献
6.
采用2013—2018年5—9月ECMWF细网格资料和阿勒泰地区36次短时强降水资料,用Micaps平台的模式探空模块计算T-log P图及其对流参数,运用统计学方法进行了误差检验。结果表明:模式探空T-log P图48 h预报时效内一致性较高(72%),尤其是24 h预报时效内(92%);72 h预报时效内总指数和干暖盖指数及垂直风切变、60 h预报时效内沙氏指数、48 h预报时效内风暴相对螺旋度和36 h预报时效内850与500 hPa温度差、对流温度、最大抬升指数、抬升指数以及24 h预报时效内K指数、700与850 hPa假相当位温差、大风指数等对流参数的3种误差均较小(3.5),相关系数较高(0.60),特别是沙氏指数、K指数、700与850 hPa假相当位温差、垂直风切变和风暴相对螺旋度的3种误差1.5。T-log P图的一致性随时效的延长而减小,对流参数的误差随预报时效的延长变化不一致,在强对流潜势预报业务中注意订正运用。 相似文献
7.
北京快速更新循环预报系统（BJ-RUC）要素预报质量评估 总被引：4，自引：2，他引：2
使用自动站观测资料对BJ-RUC系统预报的北京15个观测站的逐时2 m温度、相对湿度、1小时降水量和风速等地面要素质量进行检验评估。结果表明：BJ-RUC系统预报的2 m温度、相对湿度和风速与实况具有一致的变化趋势,但各要素的预报性能不尽相同。结果表明：（1）对于2 m温度的预报,±1℃误差的准确率为0.2～0.5,±2℃误差的准确率更高;预报性能与预报时效无明显关系;温度预报准确性与季节和日变化有关,春、秋季优于冬、夏季,夜间优于白天。（2）对相对湿度的预报整体偏低,夏季白天偏低、冬季白天偏高。（3）对1小时降水的预报,无论全年还是夏季,晴雨预报准确率很高;对0.1 mm降水的TS评分在0.2左右。（4）对不同站点的预报性能存在明显差异。对平原地区,即海拔高度较低的站点预报性能相对较好,15个站点中,对北京的代表站点（南郊观象台）的预报最为准确;对山区站点的预报性能相对较差,对海拔最高的延庆站的预报性能最差。总体来说,BJ RUC对站点要素预报的变化趋势较好,预报准确率较高,具有很好的参考价值,但要素预报与季节、日变化及海拔高度等因素有关.具体应用时还需做适当订正。 相似文献
8.
采用基于历史资料的模式距平订正法(ANO),利用2011~2015年欧洲中心高分辨率数值预报(ECMWF)的地面2m温度和广西区域自动站气温观测资料,对2016年广西区域2m温度预报进行订正试验,对比分析订正前和订正后的预报误差,结果表明:EC对广西区域2m温度的预报误差随着预报时效增加而逐渐增大,午后误差较大,夜间误差较小,预报值大多偏低。0~72h预报(较短预报时效)冬季误差较小,夏季误差较大;72~240h预报(较长预报时效)夏季误差较小,秋季和冬季误差较大。随预报时效增加,误差增大的幅度夏季较小,冬季较大。误差的离散度在较短预报时效的午后为冬季较小,夏季较大,在较长预报时效及夜间则与之相反。ANO方法对午后温度预报的订正效果优于当日其他时刻。该方法对夏季的温度预报有很好的订正效果,秋季的订正效果次之,春季的订正效果不明显,冬季的订正效果为负面作用。 相似文献
9.
延伸期温度预报误差订正技术初探 总被引：1，自引：0，他引：1
应用滑动平均误差订正方法和历史偏差订正方法,对欧洲中期天气预报中心的数值模式延伸期2 m温度预报进行误差订正。研究发现,应用滑动平均误差订正方法进行11～15 d逐日温度预报订正时,25～30 d是最优的训练期长度。对2018年订正预报的检验分析显示,应用上述两种误差订正方法均可减小模式预报的系统偏差,有效修正模式温度预报较实况明显偏低的问题,并将预报准确率提高30%以上。在6—10月,订正后的温度预报平均绝对误差基本在2℃以内,具有一定的参考性,其业务化产品可支撑预报员的业务预报需求。在15 d内的延伸期预报时效上,两种订正方法对温度预报的订正效果差异并不明显。随着时效的延长,历史偏差订正方法的优势逐渐显现。 相似文献
10.
基于中尺度数值模式快速循环系统的强对流天气分类概率预报试验 总被引：12，自引：9，他引：3
在利用实况探空资料、微波辐射计和风廓线构建的特种探空资料对北京地区强对流天气进行判别,以及快速更新循环同化预报系统(BJ-RUC模式)探空资料可应用性分析的基础上,针对模式探空基本要素计算多种热力、动力、综合不稳定物理量,根据统计的强对流天气判别指标,计算模式格点上的强对流发生概率,并进一步针对冰雹(雷暴大风)和强对流短时暴雨天气下不同物理量的阈值范围,初步探索中尺度数值模式对强对流天气分类预报的可能性.通过不同组合的预报方案进行的对比分析表明,利用北京地区中尺度数值模式快速循环系统(BJ-RUC)的格点探空资料进行强对流天气概率的预报是可以实现的,强对流天气的分类概率预报也存在一定的成功率. 相似文献
11.
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
12.
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
13.
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
14.
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
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《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
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《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
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《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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《大气和海洋科学快报》2012,(3):273
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences 相似文献