气候变化领域集成服务门户(CCPortal): The representation of the trade winds in ECMWF forecasts and reanalyses during EUREC4 A

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DOI	10.5194/acp-22-13049-2022
	The representation of the trade winds in ECMWF forecasts and reanalyses during EUREC4 A
	Savazzi, Alessandro Carlo Maria; Nuijens, Louise; Sandu, Irina; George, Geet; Bechtold, Peter
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	13049
结束页码	13066
卷号	22 期号:19 页码:18
英文摘要	The characterization of systematic forecast errors in lower-tropospheric winds is an essential component of model improvement. This paper is motivated by a global, long-standing surface bias in the operational medium-range weather forecasts produced with the Integrated Forecasting System (IFS) of the European Centre for Medium-Range Weather Forecasts (ECMWF). Over the tropical oceans, excessive easterly flow is found. A similar bias is found in the western North Atlantic trades, where the EUREC 4 A field campaign provides an unprecedented wealth of measurements. We analyze the wind bias in the IFS and ERA5 reanalysis throughout the entire lower troposphere during EUREC4 A. The wind bias varies greatly from day to day, resulting in root mean square errors (RMSEs) up to 2.5 m s(-1), with a mean wind speed bias up to -1 m s(-1) near and above the trade inversion in the forecasts and up to -0.5 m s(-1) in reanalyses. These biases are insensitive to the assimilation of sondes. The modeled zonal and meridional winds exhibit a diurnal cycle that is too strong, leading to a weak wind speed bias everywhere up to 5 km during daytime but a wind speed bias below 2 km at nighttime that is too strong. Removing momentum transport by shallow convection reduces the wind bias near the surface but leads to stronger easterly near cloud base. The update in moist physics in the newest IFS cycle (cycle 47r3) reduces the meridional wind bias, especially during daytime. Below 1 km, modeled friction due to unresolved physical processes appears to be too strong but is (partially) compensated for by the dynamics, making this a challenging coupled problem.
学科领域	Environmental Sciences; Meteorology & Atmospheric Sciences
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Meteorology & Atmospheric Sciences
WOS记录号	WOS:000865801700001
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/273291
作者单位	Delft University of Technology; European Centre for Medium-Range Weather Forecasts (ECMWF); Max Planck Society
推荐引用方式 GB/T 7714	Savazzi, Alessandro Carlo Maria,Nuijens, Louise,Sandu, Irina,et al. The representation of the trade winds in ECMWF forecasts and reanalyses during EUREC4 A[J],2022,22(19):18.
APA	Savazzi, Alessandro Carlo Maria,Nuijens, Louise,Sandu, Irina,George, Geet,&Bechtold, Peter.(2022).The representation of the trade winds in ECMWF forecasts and reanalyses during EUREC4 A.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(19),18.
MLA	Savazzi, Alessandro Carlo Maria,et al."The representation of the trade winds in ECMWF forecasts and reanalyses during EUREC4 A".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.19(2022):18.