Tropical analysis uncertainties and Kelvin waves: what can be learnt
from the Aeolus wind profiles?
- Nedjeljka Žagar,
- Michael Rennie,
- Lars Isaksen
Universität Hamburg, Meteorological Institute
Corresponding Author:firstname.lastname@example.orgAuthor Profile
AbstractThe 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.