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1.
通过对2011—2012年期间欧洲中心、日本、T639、WRF各家数值预报24 h降水预报产品插值到贵州省85个县观测站,对比每日累计实况降水量,划分为≥0.1 mm(晴雨)、≥10.0 mm(中雨以上)、≥25.0 mm(大雨以上)共3个等级进行了评估。结果发现:欧洲中心细网格和T639在贵州省各个量级降水预报均有偏大的趋势;日本模式在大雨以上量级的降水预报中对我省有偏少的趋势;WRF模式在晴雨预报中表现最好,而在明显降水的预报中表现略差。预报结果空间分布显示:欧洲中心细网格对贵州中部一线地区的明显降水预报较好;T639模式在一般性降水预报中与其他模式效果相当,但在大雨以上量级的预报中表现出明显的地区差异;日本模式在贵州东北部地区效果明显;WRF模式大雨以上量级的预报效果总体差异并不大,主要有3个大值中心,分别位于省的北部边缘、西部边缘和南部边缘,说明在以上地区WRF对大雨以上降水的预报效果具有一定的参考意义。 相似文献
2.
SWAN中定量降水估测和预报产品的检验与误差分析 总被引：1，自引：0，他引：1
采用2010—2011年5—9月河南省区域加密自动站雨量和全省6部新一代天气雷达资料,用点对点统计检验评分方法,分析SWAN系统中定量降水估测(QPE)和定量降水预报(QPF)产品在河南省短时强降水过程中的误差分布,并分别讨论二者在河南省区域与局地强降水过程中的差别及产生误差的直观原因。结果表明:1)SWAN中QPE和QPF均对小时雨量低于10 mm的降水有较好的估测和预报能力;QPE以豫西南和豫北效果最好,QPF在豫中地区预报能力更强。QPE估测较实况偏大;QPF对小时雨量低于20 mm的短时强降水预报略偏大,而对更强降水预报偏小,尤以豫西和豫南最明显。2)QPE和QPF均对区域性降水有更好的估测或预报能力。3)区域降水过程中,QPE对降水中心范围和位置估测较准确,估测值较实况偏大;QPF对强降水中心位置预报略有偏差,其中心强度较实况偏弱。 相似文献
3.
运用气象观测资料和GRAPES、ECMWF、SWCWARMS_9KM(简称SWC)模式预报资料,对冕宁“6.26”大暴雨天气过程模式预报性能进行检验。结果表明:（1）对于24 h累计降水预报,中尺度区域模式优势明显,量级与落区预报效果均为最好,其中GRAPES_3KM模式预报落区分布与实况重合度较高,暴雨及以上量级降水TS评分最高。（2）GRAPES_3KM模式最大小时雨强10 mm以上降水落区与实况大雨及以上量级降水落区匹配度最高,ECMWF模式24 h累计降水多物理量订正产品及短时强降水概率产品次之。（3）SWC及GRAPES_3KM模式24 h累计降水极值点相比实况略偏北,量级偏小。对于小时降水峰值出现时间,SWC模式偏早4 h,GRAPES_3KM模式偏早3 h。（4）GRAPES_GFS模式环流背景预报更接近实况,SWC模式能较好地预报出冕宁上空中尺度辐合系统的存在。 相似文献
4.
利用安庆市逐日降水实况资料,针对2011—2016年ECMWF细网格降水预报产品对安庆地区的12 h、24 h分辨率晴雨和降水分级预报质量进行检验,基于检验结果对此降水预报产品进行解释应用。结果表明,ECMWF细网格数值降水预报在安庆地区晴雨预报正确率无明显区域差异,夏季晴雨预报正确率明显低于其他各季节,对夜间的预报能力明显优于白天。TS评分中,小雨最高,中雨次之,大雨及以上量级较低且无明显规律。若将冬、春两季0.2 mm以下、夏季1.0 mm以下和秋季0.8 mm以下的降水预报进行消空处理,则晴雨预报正确率会有所提升,且小雨预报的TS评分达最佳;若将≥40 mm的降水预报修正为暴雨,则暴雨预报TS评分提高接近1倍,且大雨和暴雨的预报偏差更接近1。 相似文献
5.
基于中国西北四省(区)2016—2017年的站点观测降水数据和GRAPES区域数值模式24 h和48 h预报结果,采用平均误差、均方根误差、相关系数、分等级TS评分等指标,对GRAPES区域数值模式在西北四省(区)降水预报进行定量评估。结果表明:时间上,模式对西北四省的晴雨预报准确率能达到0.7以上,逐日空间相关系数为0.2～0.4。夏季降水的偏差最大,24 h和48 h预报平均误差分别为4、6 mm·d~(-1),均方根误差分别为6、8 mm·d~(-1)。不同等级降水的24 h和48 h预报TS评分显示,各个月份小雨TS评分为0.2～0.5,中雨为0.1～0.2,大雨以上不到0.1空间上,24 h和48 h预报晴雨准确率在大部分地区达到0.6以上,相关系数在甘肃东部、陕西中部和南部超过0.6。24 h预报平均误差在青海、甘肃、陕西三省南部最大(达到2～4 mm·d~(-1)),48 h预报的平均误差比相同区域的24 h预报高出1～2 mm·d~(-1),在陕西南部平均误差最大(达到5～8 mm·d~(-1))。各个量级的24 h预报TS评分明显好于48 h,24 h预报对大雨、暴雨有所预报,48 h预报对中雨以上量级降水预报较差。 相似文献
6.
为做好ECMWF(European Centre for Medium-Range Weather Forecasting)模式本地化释用，提高四川省降水预报准确率，对四川省2020—2021年7—9月模式各量级降水预报系统性偏差规律分析发现，该模式预报的雨日较实况偏多，尤其是攀西地区和川西高原；预报的大雨日数盆地西南部及攀西地区多于实况，而盆地南部少于实况。然后，基于分位数映射法对模式预报的24 h累积降水开展大量级降水订正试验与检验。基于分位数映射法订正后，暴雨及以上量级TS(Threat Score)提高7%～15%，且各量级降水TS均高于多模式集成客观预报产品2%～4%，大雨及以上、暴雨及以上量级命中率提高10%～20%，订正后雨带位置特别是暴雨落区与实况更接近。 相似文献
7.
新发展了一种湿Q矢量释用技术:利用松弛法迭代求解以非地转干Q矢量散度为强迫项的方程得到垂直运动场ω 1, 然后由ω 1计算湿Q矢量散度场, 接着再利用松弛法迭代求解以湿Q矢量散度场为强迫项的ω方程得到垂直运动ω 2, 最后由ω 2结合水汽条件进行降水量计算, 得到湿Q矢量释用降水场。结合一次典型的江淮梅雨锋暴雨过程研究表明, 湿Q矢量释用降水场对同期观测降水场水平分布特征、极端降水强度都具有一定的反映能力, 反映出湿Q矢量释用技术具备实际应用的可行性和一定合理性。将此释用技术应用于华东区域数值预报模式 (基于MM5 V3.6而建立, 以下简称MM5) 产品, 得到湿Q矢量释用定量降水预报 (QPF) 场, 其独立于模式本身输出的QPF场, 但与模式QPF场具有相同的时空分辨率。针对2004年6—8月汛期华东地区一次梅雨锋降水过程和一次登陆台风降水过程, 结合实况雨量资料, 比较分析了湿Q矢量释用QPF场和MM5模式QPF场对实际观测降水场的反映能力, 结果表明, 前者对有无降水、10.0 mm/24 h以上明显降水的反映能力明显优于后者。进一步进行预报统计检验表明, 湿Q矢量释用预报有无降水、小雨及10.0 mm/24 h以上降水的TS评分、正确率都明显高于MM5模式, 而漏报率、空报率则是前者明显低于后者。这也充分反映出湿Q矢量释用技术应用于QPF研究的有效性。最后, 探讨了数值预报产品释用技术对数值预报模式性能的依赖性, 并指出未来对湿Q矢量释用技术进一步改进的方向及其广泛应用前景。 相似文献
8.
摘要：目前贵州在短时临近降水预报客观算法方面研究匮乏，而短时强降水常常给贵州造成严重的洪涝灾害和地质灾害。将短时临近降水预报应用于气象防灾减灾、电网输电线路安全预警、水利防洪自动化方面是未来重要的研究应用方向。本文基于灾害天气短时临近系统（Severe Weather Automatic Nowcast System，SWAN）的定量降水预报(QPF)产品进行0～2小时QPF外推试验研究。利用贵州省地面自动站数据、SWAN 输出的1h-QPF产品、SWAN 1h定量降水估测(QPE)产品。选取2018年3次典型暴雨个例进行试验，采用融合订正技术，利用相似离度算法对降水强度位相进行调整、Weibull分布算法对降水极值分布进行订正、改进后的交叉相关法(Improved Cross-correlation Extrapolation Method，COTREC)进行降水外推预报。通过主客观检验对比，初步说明基于Weibull分布算法的降水极值订正对降水极值分布有很好的模拟效果。融合订正外推的贵州省短时临近定量降水预报产品（Nowcasting precipitation forecast of GuiZhou，下文简写为GZ_NPF）在大于5mm以上量级降水的TS检验中评分更高。GZ_NPF的空报率明显降低，但空报率降低的代价是漏报率相对提高。GZ_NPF总的相对误差减小，格点总降水量与实况总降水量更为接近。试验说明新的融合订正外推算法提高了0～2h短时临近降水的预报能力。 相似文献
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10.
对2016-2020年全球模式ECMWF和区域模式GZ_GRAPES、基于模式的解释应用和广东省气象局发布的定量降水预报（QPF）进行检验和评估。结果表明:ECMWF和GZ_GRAPES模式对一般性降水预报技巧在逐年提升,对大雨或以上的降水预报技巧的提升缓慢。GZ_GRAPES对大雨以上降水的预报技巧和定量降水预报的精细时空分布均优于ECMWF,区域模式更易预报出中小尺度降水信息。分类暴雨评定表明,模式对台风暴雨预报最好、锋面暴雨次之、季风暴雨预报最差。模式的暴雨预报落区偏小、低估明显,预报员通过经验订正明显提升了暴雨预报评分,其中季风暴雨的订正量最大,但存在预报范围偏大、空报较高的问题。基于ECMWF集合预报的解释应用与预报员的定量降水预报能力相当,降水越强,解释应用技术的优势越明显,但对季风暴雨也存在严重低估或漏报。目前降水精细时空分布、季风暴雨、极端性暴雨等依然靠预报员的经验订正为主,随着集合预报模式和区域高分辨率模式能力的提升,将预报经验客观化并与数值预报解释应用技术结合是提升QPF的一个方向。 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.
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
13.
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
14.
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
15.
Fei LIU Chen XING Jinbao LI Bin WANG Jing CHAI Chaochao GAO Gang HUANG Jian LIU Deliang CHEN 《大气科学进展》2020,37(7):663-670
正The Taal Volcano in Luzon is one of the most active and dangerous volcanoes of the Philippines. A recent eruption occurred on 12 January 2020(Fig. 1a), and this volcano is still active with the occurrence of volcanic earthquakes. The eruption has become a deep concern worldwide, not only for its damage on local society, but also for potential hazardous consequences on the Earth's climate and environment. 相似文献
16.
The moving-window correlation analysis was applied to investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the synchronous autumn precipitation in Huaxi region, based on the daily precipitation, sea surface temperature (SST) and atmospheric circulation data from 1960 to 2012. The correlation curves of IOD and the early modulation of Huaxi region’s autumn precipitation indicated a mutational site appeared in the 1970s. During 1960 to 1979, when the IOD was in positive phase in autumn, the circulations changed from a “W” shape to an ”M” shape at 500 hPa in Asia middle-high latitude region. Cold flux got into the Sichuan province with Northwest flow, the positive anomaly of the water vapor flux transported from Western Pacific to Huaxi region strengthened, caused precipitation increase in east Huaxi region. During 1980 to 1999, when the IOD in autumn was positive phase, the atmospheric circulation presented a “W” shape at 500 hPa, the positive anomaly of the water vapor flux transported from Bay of Bengal to Huaxi region strengthened, caused precipitation ascend in west Huaxi region. In summary, the Indian Ocean changed from cold phase to warm phase since the 1970s, caused the instability of the inter-annual relationship between the IOD and the autumn rainfall in Huaxi region. 相似文献
17.
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
18.
基于最新的GTAP8 (Global Trade Analysis Project）数据库,使用投入产出法,分析了2004年到2007年全球贸易变化下南北集团贸易隐含碳变化及对全球碳排放的影响。结果显示,随着发展中国家进出口规模扩张,全球贸易隐含碳流向的重心逐渐向发展中国家转移。2004年到2007年,发达国家高端设备制造业和服务业出口以及发展中国家资源、能源密集型行业及中低端制造业出口的趋势加强,该过程的生产转移导致全球碳排放增长4.15亿t,占研究时段全球贸易隐含碳增量的63%。未来发展中国家的出口隐含碳比重还将进一步提高。贸易变化带来的南北集团隐含碳流动变化对全球应对气候变化行动的影响日益突出,发达国家对此负有重要责任。 相似文献
19.
Using the International Comprehensive Ocean-Atmosphere Data Set(ICOADS) and ERA-Interim data, spatial distributions of air-sea temperature difference(ASTD) in the South China Sea(SCS) for the past 35 years are compared,and variations of spatial and temporal distributions of ASTD in this region are addressed using empirical orthogonal function decomposition and wavelet analysis methods. The results indicate that both ICOADS and ERA-Interim data can reflect actual distribution characteristics of ASTD in the SCS, but values of ASTD from the ERA-Interim data are smaller than those of the ICOADS data in the same region. In addition, the ASTD characteristics from the ERA-Interim data are not obvious inshore. A seesaw-type, north-south distribution of ASTD is dominant in the SCS; i.e., a positive peak in the south is associated with a negative peak in the north in November, and a negative peak in the south is accompanied by a positive peak in the north during April and May. Interannual ASTD variations in summer or autumn are decreasing. There is a seesaw-type distribution of ASTD between Beibu Bay and most of the SCS in summer, and the center of large values is in the Nansha Islands area in autumn. The ASTD in the SCS has a strong quasi-3a oscillation period in all seasons, and a quasi-11 a period in winter and spring. The ASTD is positively correlated with the Nio3.4 index in summer and autumn but negatively correlated in spring and winter. 相似文献
20.
Hourly outgoing longwave radiation(OLR) from the geostationary satellite Communication Oceanography Meteorological Satellite(COMS) has been retrieved since June 2010. The COMS OLR retrieval algorithms are based on regression analyses of radiative transfer simulations for spectral functions of COMS infrared channels. This study documents the accuracies of OLRs for future climate applications by making an intercomparison of four OLRs from one single-channel algorithm(OLR12.0using the 12.0 μm channel) and three multiple-channel algorithms(OLR10.8+12.0using the 10.8 and 12.0 μm channels; OLR6.7+10.8using the 6.7 and 10.8 μm channels; and OLR All using the 6.7, 10.8, and 12.0 μm channels). The COMS OLRs from these algorithms were validated with direct measurements of OLR from a broadband radiometer of the Clouds and Earth's Radiant Energy System(CERES) over the full COMS field of view [roughly(50°S–50°N, 70°–170°E)] during April 2011.Validation results show that the root-mean-square errors of COMS OLRs are 5–7 W m-2, which indicates good agreement with CERES OLR over the vast domain. OLR6.7+10.8and OLR All have much smaller errors(～ 6 W m-2) than OLR12.0and OLR10.8+12.0(～ 8 W m-2). Moreover, the small errors of OLR6.7+10.8and OLR All are systematic and can be readily reduced through additional mean bias correction and/or radiance calibration. These results indicate a noteworthy role of the6.7 μm water vapor absorption channel in improving the accuracy of the OLRs. The dependence of the accuracy of COMS OLRs on various surface, atmospheric, and observational conditions is also discussed. 相似文献