Abstract

The European Space Agency Earth Explorer mission Aeolus with the first spaceborne Doppler Wind Lidar onboard provides the global coverage of wind profiles twice per day. This paper discusses the impact of Aeolus winds on the quality of tropical analyses using the observing system experiments of the European Centre for Medium Range Weather Forecasts. Focusing on a period in May 2020, it is shown that Aeolus winds improve the fit of short-term forecasts to observations for other observations types, in spite of their random errors significantly greater than error estimates for short-term tropical forecasts. It is argued that Aeolus winds lead to more accurate representation of the vertically-propagating equatorial waves in the tropical upper troposphere. Examples of Kelvin waves suggest that analysis increments occur in the layers with a significant vertical shear during the easterly phase of the quasi-biennial oscillation in May 2020.