###
DOI:
本文二维码信息
ECMWF降水相态预报产品(PTYPE)应用和检验
董全
(国家气象中心 北京 100081)
Application and Verification of the ECMWF Precipitation Type Forecast Product (PTYPE)
DONG Quan
(National Meteorological Centre)
摘要
相似文献
本文已被:浏览 331次   下载 197
投稿时间:2019-07-31    修订日期:2020-03-06
中文摘要: 本文运用我国过去2016-2018年三个冬半年(10月至次年3月)地面2000多站的天气现象观测资料,对ECMWF(European Centre for Medium-Range Weather Forecasts)的降水相态预报产品(PTYPE)对我国(分为雨、雨夹雪、雪和冻雨四类)的预报效果进行了系统性的检验评估,包括细网格确定性模式预报产品和集合预报系统概率预报产品。结果显示,ECMWF的确定性预报产品对以上四类相态降水的准确率正确率普遍都达90%以上,对降雨和降雪的TS评分也较高,冻雨次之,雨夹雪的TS评分较低,预报能力有限。确定性模式对我国雨雪分界线的预报,普遍存在短期位置略偏南、中期随时效延长越来越偏北的误差特点,且对雨夹雪的预报范围明显偏小,对冻雨的预报范围明显偏大。集合预报系统从概率的角度一定程度上弥补了确定性模式的以上述误差。对概率预报的检验结果显示,集合预报系统降雨概率普遍偏低,降雪概率短期偏高、中期偏低,而雨夹雪和冻雨概率普遍偏低,但是都有一定的预报技巧。集合预报系统相对于确定性模式的优势,降雨体现在较小花费损失比事件的预报上,降雪体现在较大花费损失比事件的预报上。对降雨和降雪,体现在特定的花费损失比事件上,但是对雨夹雪和冻雨,相对于确定性模式,集合预报系统体现出了显著的优势,尤其是冻雨,集合预报系统的优势更加明显。
Abstract:The ECMWF (European Centre for Medium-Range Weather Forecasts) precipitation type forecast products—PTYPE are verified using the weather observations of more than 2000 stations in China of the past three winter half years (October to next March). The products include the deterministic forecast from High-resolution model and the probability forecast from ensemble prediction system and the verified precipitation types include rain, sleet, snow and freezing rain. The results show that the proportion correct of deterministic forecast of ECMWF high-resolution model is mostly larger than 90% and the TSs of rain and snow are high, next is freezing rain, and the TS of sleet is small indicating that the forecast skill of sleet is limited. The rain and snow separating line of deterministic forecasts show errors of a little south in short-range and more and more significant north following elongating lead times in medium-range. The area of sleet forecasts is smaller than observations and the freezing rain is bigger for the high-resolution deterministic forecast. The ensemble prediction system offsets these errors partly by probability forecast. The probability forecast of rain from the ensemble prediction system is smaller than the observation frequency and the probability forecast of snow is larger in short-range and smaller in medium-range than the observation frequency. However, there are some forecast skills for all of these probability forecasts. There are advantages of ensemble prediction system compared to the high-resolution deterministic model. For rain and snow, for some special cost/loss ratio events the EPS is better than the HRD. For sleet and freezing rain, the EPS is better than the HRD significantly, especially for the freezing rain.
文章编号:201907310298     中图分类号:    文献标志码:
基金项目:国家科技支撑计划(2015BAC03B03,2015BAC03B01),国家重点研发计划(2017YFC1502004)
引用文本:
董全,0.[en_title][J].Meteor Mon,():-.
DONG Quan,0.Application and Verification of the ECMWF Precipitation Type Forecast Product (PTYPE)[J].Meteor Mon,():-.