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1.
正热带气旋位居全球十大自然灾害之首,至今造成全球保险损失金额最高的十大自然灾害事件中有八起与热带气旋有关。西北太平洋(含南海)是全球热带气旋最活跃的海区,中国是全世界受热带气旋影响最严重的国家之一,每年约有7~9个热带气旋登陆在我国人口稠密、经济发达的东南沿海,造成的经济损失随着经济社会发展和人口规模的增长呈日趋加重的态势。我国各级政府及中国气象局始终高度重视防台减灾工作,自1970年代起便建立了全国台风监测预警联 相似文献
2.
ASSIMILATION OF OBSERVED SURFACE WIND WITH GRAPES 总被引:2,自引:1,他引:1
With the advances of numerical weather simulation and reduced data assimilation updating
cycle, surface observation data assimilation becomes more and more important in data assimilation systems.
It is widely accepted that a better data assimilation system should contain the restriction of thermodynamic
processes in the surface layer. Therefore, in this paper, a new surface wind observation operator is utilized
in Global and Regional Assimilation PrEdiction System_3D-Variance (GRAPES_3D-Var), with the
restriction of thermodynamic process in the planetary boundary layer (PBL). In order to research the ability
of this new surface wind observation operator in assimilation and forecasting, a series of experiments are
operated by using the GRAPES model. The main results indicate that this new method of surface wind
observation operator has positive impact on the forecast with the GRAPES model. 相似文献
3.
以国家气象中心数值预报产品为依托, 根据上海区域气象中心计算机资源配置情况, 用NCAR-PSU/MM5V2作为动力框架, 确定了侧边界嵌套方案、积云参数化方案和边界层参数化方案, 研制了资料分析同化方法和预报结果后处理方法及产品显示软件, 建立了上海区域气象中心第五代数值预报业务系统, 可提供华东地区138个城市每3 h一次的地面要素预报.半年多准业务运行表明, 预报效果较好, 对区域内气象台站的业务预报有良好的参考价值. 相似文献
4.
In the context of a model of tropical cyclone intensity based on an improved meso-scaleatmospheric model, numerical simulation is performed of the track and intensity variation oftropical cyclones (TC) arising from sea surface temperature (SST) variation over a specified searegion. Evidence suggests that the model is capable of modeling quite welt the track and intensityof TC: SST variation leads to an abrupt change in the cyclone intensity: the response of thecyclone to the abrupt SST change lasts 8—12 h. 相似文献
5.
分析了2002年度苏州市矿产资源开发利用基本情况。阐述了苏州近几年在矿产资源补偿费征收和禁止开山采石方面取得的显著成效。提出了苏州矿业开发利用中存在的问题。 相似文献
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分析表明,海南岛冬半年日际气温的变化幅度很大,平均气温很难表征海南岛冬季“冷”的气候特征,从冬季农作物生长角度出发,统计海南岛发生低温冷害的气候概率,提出海南岛存在“相对的冬季”。进一步,引进“冷指数”替代平均气温来表征海南岛冬季的“冷”。对冷指数的主成分分析表明:(1)以五指山脉为界,海南岛南、北两区在冬季存在的冷暖差异,山北地区发生低温冷害的气候概率明显大于山南地区,这正是五指山脉对冷空气的抬 相似文献
10.
Constructing β-mesoscale weather systems in initial fields remains a
challenging problem in a mesoscale numerical weather prediction (NWP) model.
Without vertical velocity matching the β-mesoscale weather system,
convection activities would be suppressed by downdraft and cooling caused by
precipitating hydrometeors. In this study, a method, basing on the
three-dimensional variational (3DVAR) assimilation technique, was developed
to obtain reasonable structures of β-mesoscale weather systems by
assimilating radar data in a next-generation NWP system named GRAPES (the
Global and Regional Assimilation and Prediction System) of China.
Single-point testing indicated that assimilating radial wind significantly
improved the horizontal wind but had little effect on the vertical velocity,
while assimilating the retrieved vertical velocity (taking Richardson's
equation as the observational operator) can greatly improve the vertical
motion. Experiments on a typhoon show that assimilation of the radial wind
data can greatly improve the prediction of the typhoon track, and can
ameliorate precipitation to some extent. Assimilating the retrieved vertical
velocity and rainwater mixing ratio, and adjusting water vapor and cloud
water mixing ratio in the initial fields simultaneously, can significantly
improve the tropical cyclone rainfall forecast but has little effect on
typhoon path. Joint assimilating these three kinds of radar data gets the
best results. Taking into account the scale of different weather systems and
representation of observational data, data quality control, error setting of
background field and observation data are still requiring further in-depth
study. 相似文献