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1.
本文通过分析2017年9~12月四川地区ECMWF(European Centre for Medium-Range Weather Forecasting)细网格模式、GRAPES_GFS(Global and Regional Assimilation and Prediction System)全球模式和西南区域模式(South West Center-WRF ADAS Real-time Modeling System, SWCWARMS)2m温度168h预报时效内的系统性偏差特征,采用滑动双权重平均法分别对三种模式温度预报产品进行偏差订正,并集成得到各时效2m温度的订正场,结果表明:(1)三种模式的预报存在明显的日变化,整体上EC模式的预报最优。(2)三种模式对于低温和高温的预报,在全省均大致呈现负的系统性误差,特别在高原及过渡区表现的尤为明显。(3)订正后三种模式的预报准确率显著提高,均方根误差减小1.4~2.5℃,大部分地区平均误差维持在±0.5℃之间,在系统性偏差较大的地区,订正效果更好。(4)两种集成方案预报结果接近,且均优于三种模式的订正预报。 相似文献
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文章提出了一种结合滑动双权重平均订正法和空间误差逐步订正法的综合订正技术,并对2016年5月1日至2017年5月1日期间24～168 h预报时效内欧洲中期天气预报中心(ECMWF)高分辨率模式的2 m最高和最低温度进行偏差订正和误差分析,主要结论如下:(1)ECMWF模式在江西省的温度预报整体上比实况偏低,最高温度尤为明显,模式温度的空间分布表现出显著的系统性偏差,且偏差在不同预报时效是稳定的,订正ECMWF模式温度具有可行性。(2)滑动双权重平均订正法中较长的滑动订正周期对模式温度预报有更好的订正效果,采用滑动订正周期20 d是比较理想的。滑动双权重平均订正法具有持续的订正能力,但在季节过渡期间订正效果可能并不理想,而空间误差逐步订正法能进一步提高滑动双权重平均订正法的预报订正质量。(3)温度预报准确率表明,滑动双权重平均订正法和空间误差逐步订正法综合订正技术较好地改善了站点温度的预报质量。经过订正后,模式最高温度24、48、72 h预报误差≤2℃的准确率分别从0.59、0.55、0.52提高到0.75、0.68、0.62,模式最低温度24、48、72 h预报准确率分别从0.84、0.83、0.82提高到0.89、0.87、0.85。订正后72 h最高和最低温度的预报准确率都大于订正前模式24 h的准确率。总体而言,该综合订正技术较好地订正了模式误差,且误差在空间分布上较均匀。(4)对于高山站而言,经过订正后的最高和最低温度与实况基本吻合。空间误差逐步订正法的订正量在±1℃之内,与滑动双权重平均订正后的偏差呈现一定的负相关,有正的订正效果。该综合订正法已成功运用于江西省精细化气象要素客观预报业务系统中。 相似文献
3.
该文采用EC细网格2 m温度预报场及国家站实况资料,通过滑动平均法、双权重滑动平均法、多项式拟合法以及最佳系数法对EC细网格2 m温度在黔南州的预报进行订正分析,结果显示:4种方法订正后最高气温7 d平均准确率分别提升了12.70%~17.84%,最低气温7 d平均准确率分别提升了1.14%~2.86%。对于高温预报,最佳系数法订正效果最优,其次是多项式拟合法,对于最低气温,前3 d采用滑动平均法订正效果最明显,第4 d开始则采用最佳系数法订正,订正效果更明显。4种订正方法均在7-9月效果最明显。黔南州西部及中部地区多项式拟合法订正效果更好,州东南部地区最佳系数法与滑动平均法订正效果更好,但在120 h时效后滑动平均法的订正效果明显下降,州北部地区最佳系数法订正效果更为明显。 相似文献
4.
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
5.
诊断分析CMA-MESO(China Meteorological Administration Mesoscale Model,原GRAPES-MESO)3 km系统冬季2 m温度预报效果,为冬奥气象保障服务以及CMA-MESO模式系统开发优化改进提供参考,选取2020年12月至2021年2月2 m温度预报。诊断发现,每日低温预报较好,高温预报较差,00—06时(世界时,下同)升温过程预报效果好于06—21时降温过程。滑动双权重平均法订正显示,2 m温度预报偏差以系统性偏差为主,订正前均方根误差和标准差较大地区改善效果更为明显。依据温度订正前后标准差差异选择华北、华东、西南三个区域的个例和华北地区连续试验进行波谱分析发现,功率谱随着尺度增大逐渐增多,2 m温度预报偏差和2 m温度不同尺度功率谱信息存在一定的对应关系,当不同尺度上的功率谱存在缺失或异常大值时,2 m温度预报与实况存在明显差异。 相似文献
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利用滑动平均法和递减平均法对2013—2014年江西省1 216个乡镇站点ECMWF集合预报2 m温度集合平均产品进行误差订正试验。结果表明:1)滑动平均法和递减平均法对江西地区乡镇温度预报为正的订正效果,订正后的预报准确率大于订正前,并且递减平均法的订正效果要略优于滑动平均法。2)误差订正方法对各时段温度TRMSE的订正能力都随预报时效的增加而减小,对高温预报准确率的提高明显大于低温,对山区预报准确率的提高大于平原,对有规律的预报误差的站点订正效果较好。3)随季节和站点变化的自适应递减平均法的预报结果较各季节和全年定常最优订正系数好,订正方法对秋季温度预报订正能力最强,春季最差。 相似文献
7.
T639模式预报系统误差统计和订正方法研究 总被引：4，自引：2，他引：2
通过统计2009—2010年T639模式500 hPa高度、850 hPa温度和2 m温度的1～10天预报场的平均误差发现,T639模式的这些气象要素预报都存在明显系统误差,且系统误差随着预报时效的增加而增加。利用＂递减平均法＂尝试订正其预报系统误差,订正结果表明：该订正方法总体表现为正的订正技巧,但订正能力随着预报时效的增加而下降;东亚地区的系统误差小于整个北半球,＂递减平均法＂的订正能力总体小于整个北半球。对比夏、冬半年订正效果发现：对于500 hPa位势高度和850 hPa温度的预报场,冬半年和夏半年订正技巧相当;对于地面2 m温度预报场,冬半年订正能力明显高于夏半年。不同权重系数试验表明：对于500 hPa高度场,权重系数约取0.06时,订正效果较好,而对于850 hPa和2 m温度场,权重系数约取0.1时,订正效果最佳。 相似文献
8.
为了提高GRAPES_3 km（Global/Regional Assimilation and Prediction System）模式在2018年平昌冬奥会气象服务中的预报能力,采用一阶自适应的卡尔曼滤波方法对GRAPES_3 km模式的2 m气温、2 m相对湿度和10 m风开展偏差订正。结果表明:偏差订正方法明显提高了地面要素的预报效果,其中2 m气温的均方根误差整体减小到2℃左右,站点订正改善率为10%~60%;10 m风速的均方根误差减小到2 m·s-1左右,站点订正改善率为10%~45%;2 m相对湿度减小到20%以下,站点订正改善率为0~20%。与韩国气象厅LDAPS（Local Data Assimilation and Prediction System）及美国宇航局NU-WRF（NASA-Unified WRF）模式相比,GRAPES_3 km模式的风速预报表现更为优异,各站点整体预报效果明显优于LDAPS和NU-WRF模式。偏差订正方法可有效改善模式在复杂地形条件下的预报能力,是提高精细化预报准确率的重要手段。 相似文献
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本文选取2017年1~12月ECMWF(European Centre for Medium-Range Weather Forecasting)细网格模式168h预报时效的2m温度场和对应时段四川地区157个国家站的观测资料,对比分析了模式温度预报的系统性偏差特征,采用15日周期的滑动双权重平均法对2m温度预报产品进行偏差订正,并与四川省气象台现有的主、客观预报产品进行对比,结果表明:(1)EC模式对低温的预报准确率远高于高温预报准确率;订正后高、低温预报准确率均有显著提高,其中低温平均提高了20.5%,高温提高了31.2%,平均绝对误差分别减小约1.1℃和2.9℃。(2)EC模式高温预报的逐月差异明显比低温预报逐月差异大,订正后差异明显减小,且各月的高、低温预报准确率均有显著提升,订正后各月高、低温的平均绝对误差均在2℃之内。(3)EC模式对于低温和高温的预报在全省均大致呈现负的系统性误差,且高温预报的系统性误差明显比低温预报的系统性误差大,订正后2m温度预报的系统性误差均明显降低,全省大部分地区维持在±1℃之间。(4)与四川省气象台现有的主、客观预报产品对比显示,对于高低温预报均是EC订正后准确率最高、平均绝对误差最小,订正效果较为理想。 相似文献
10.
利用国家气象信息中心CLDAS格点温度实况、中央气象台SCMOC格点温度预报以及山西省站点观测温度,采用非独立性检验综合评估CLDAS在山西区域的适用性。在此基础上,采用滑动训练期订正方案,基于格点实况开展SCMOC温度预报场的客观订正。结果表明:(1)复杂地形对山西CLDAS格点温度实况的精度有一定影响,但最高气温的分析精度优于最低气温,表明地形对最低气温的偏差影响更显著,高海拔地区CLDAS最低气温一般对应为负偏差,低海拔地区一般对应为正偏差。(2)CLDAS格点温度实况的偏差空间分布具有时间延续性,进行简单的系统偏差订正后,最高、最低气温格点实况的精度分别提升1.1%、9.7%,与站点观测更为吻合。(3)基于改进后的CLDAS格点温度实况,采用滑动偏差订正方案,显著改善了山西省SCMOC温度预报的准确率。2019年,滑动偏差订正后的24 h时效最高、最低气温预报准确率较SCMOC温度预报分别提升2.7%、4.7%,订正后的短期温度预报质量有较大提高,优于预报员主观预报。 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
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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
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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
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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