Aeolus Introduction

ADM-Aeolus is the second of ESA’s Earth Explorer core missions. The objective is to provide profiles of high-quality wind observations from the surface to 30 km, using a Doppler wind lidar (DWL) instrument in a near-polar sun-synchronous, dawn-dusk orbit. The wind information is the horizontal line-of-sight component, perpendicular to the satellite track. The mission is intended to have a minimum lifetime of three years.
ECMWF is leading the project to develop (in close collaboration with KNMI) the Aeolus Level 2B/C processing software i.e. wind retrieval.  The L2B wind retrieval algorithms have also been developed in the past in collaboration with Météo-France, DLR and LMD/IPSL.  ECMWF will also generate the L2B products in an operational fashion at ECMWF (and provide the products to ESA) and we intend to assimilate the L2B winds in our global NWP model.  Aeolus will also provide information on the optical properties of cloud and aerosol (via the L2A product), with ALADIN being a High Spectral Resolution Lidar; the L2A product may have applications in the atmospheric composition model at ECMWF.  ECMWF has contributed to a number of ESA funded data impact studies to assess the potential impact of the Aeolus data. We expect the Aeolus mission to have a positive impact on forecast and analysis quality, in particular for the tropical winds.

The L2B processing software

ECMWF and KNMI are responsible for the development of the ADM-Aeolus wind retrieval software (the Level-2B processor) which produces Horizontal Line of Sight (HLOS) winds suitable for use in NWP and meteorological research.  The algorithms are described in Tan et al. (Tellus, A, 2008, 60, 2, 191-205), however there have been many improvements since then.

Obtaining the L2B processing software

• The ADM-Aeolus Level-2B/C processing documentation (including the Software Release Note, the Algorithm Theoretical Baseline and the Input/Output Data Definitions Interface Control Document) and associated datasets (needed to test the success of the installation) can be freely downloaded from here
• The source code can be downloaded from from our website (upon acceptance of the licence terms) 
• Any news on updates to the software, e.g. new deliveries, will be provided here
• Technical Notes prepared for ESA which are related to the L2B/C processing can be downloaded here (they are useful to help understand what the L2B products are like)