浙江近海冬季大风风速推算和ASCAT风速订正方法探讨  

Analysis on Methods About the Winter Offshore Gale Speed Estimation and ASCAT Wind Correction in Zhejiang

作　　者：姚日升[1,2] 涂小萍[1,2] 蒋璐璐 丁烨毅 王武军 

机构地区：[1]浙江省宁波市气象台,宁波315012 [2]宁波大学宁波市非线性海洋和大气灾害系统协同创新中心,宁波315211 [3]浙江省奉化市气象局,奉化315500

出　　处：《气象》2016年第5期621-627,共7页Meteorological Monthly

基　　金：浙江省自然科学基金(LY15D050001);宁波市科技计划项目(2012C50044);宁波市气象局科技计划项目(NBQX2014005B)共同资助

摘　　要：利用2010—2014年12月至次年2月浙江省自动气象站测风资料和ASCAT散射计反演的风场资料,通过模糊聚类空间分型,选取有代表性的站点建立浙江近海冷空气大风的风速推算公式,并对ASCAT近海风场产品进行误差分析和风速订正。结果表明:冷空气影响时浙江北部近海多数自动站与舟山浮标站相比有偏南风矢量差,南部近海自动站比温州浮标站有东南风矢量差,自动站风速一般小于浮标站。海拔高度与自动站和浮标站风速差值δ相关性不显著,站点离岸距离是影响δ的主要因子。冷空气影响时浙江近海ASCAT反演风速与实况相关系数的分布具有平行于海岸线且自西向东增大的特征,相关系数超过0.5的站点一般离岸30 km以上,舟山和温州12个浮标站测风与ASCAT反演风具有较好的相关性。浙江近海ASCAT风速的误差空间差异较大,经订正后的风速分布也具有平行于海岸线、自西向东逐渐增大的特征,且与观测的误差绝对值一般小于2 m·s^(-1)。Using the wind observation data of automatic weather stations（AWSs） in Zhejiang Province during December and February from 2010 to 2014 and the retrieved ASCAT winds,and by means of the Fuzzy Cluster Mean（FCM）,an offshore wind speed calculation formula is established and the error analysis for ASCAT products during cold air events in the Zhejiang coast is carried out.The results show that the most AWSs in northern Zhejiang coast have a southerly vector difference compared with the winds at Zhoushan Buoy,the AWSs in the southern coast have a southeasterly vector difference compared with the Wenzhou Buoy,and the AWSs wind speeds generally are smaller than wind speeds from the buoys.The analysis also indicates that altitudes impact little the wind speed differences（8） between the AWSs and buoys,and the distance of the stations from the coastline is the main factor that impacts the 8 value.When cold air strikes the Zhejiang offshore,the distribution of the correlation coefficients between the ASCAT and observations has the characteristics of paralleling to the coastline and increasing from the west to the east.Generally,the distance from the stations to the coastline is usually more than 30 km when coefficients are more than 0.5.The observed winds from Zhoushan and Wenzhou Buoys have a good correlation with the retrieved ASCAT winds.But there is a large special difference in the ASCAT winds error in Zhejiang offshore.The distribution of the corrected ASCAT wind speed also has a characteristic of paralleling to the coastline and increasing from the west to the east,and its absolute error is less than 2 m ？ s^（-1） compared with the observed speed.

关 键 词：大风 模糊聚类 逐步回归 浮标站 ASCAT 风速订正 

分 类 号：P425[天文地球—大气科学及气象学]