ESA PECS STUDY ARRANGEMENT REPORT
No ESA PECS Study Arrangement Report will be accepted unless this sheet is inserted at the beginning of each volume of the Report.
ESA Contract (Arrangement) No:
4000106730/12/NL/KML
SUBJECT:
Multivariate relationships between the aerosols, moisture and winds in four- dimensional data assimilation for the global monitoring for environment and security
INSTITUTE:
University of Ljubljana (Faculty of Mathematics and Physics)
* ESA CR( )No: No. of Volumes: 1
This is Volume No: 1
INSTITUTE’S REFERENCE:
ESA-Zagar2-2016-Final report ABSTRACT: In recent years the increasing amount of remotely sensed data on atmospheric trace constituents has been provided by several satellites in addition to numerous observations of the atmospheric vertical temperature and moisture profiles. At the same time, a lack of wind measurements over many parts of the globe has been recognized as the main shortcoming of the current global observing system. New wind observations from ADM-Aeolus will have limited duration and the observation gap will remain. This project deals with potential for estimating wind field from atmospheric aerosol and moisture observations in the four-dimensional variational (4D-Var) data assimilation.
The project has developed a new model of intermediate complexity to simulate the aerosol, moisture, temperature and wind interactions in the tropical atmosphere Observing system simulation experiments are used to address the potential of aerosol and moisture observations in 4D-Var. It is shown that the extraction of wind information strongly depends on the density of aerosol observations and the applied background-error term in 4D-Var. Within the applied perfect-model framework and using dense tracers observations, the 4D-Var assimilation can reduce the background errors up to about 10%. There results are similar for the dry and moist conditions. In the moist atmosphere without wind observations, it is most beneficial for the wind analysis to assimilate dense moisture observations together with temperature and aerosols.
Furthermore, the long assimilation window significantly improves wind retrieval in the perfect- model 4D-Var.
The work described in this report was done under ESA PECS Arrangement. Responsibility for the contents resides in the author or organisation that prepared it.
Names of authors: Žiga Zaplotnik and Nedjeljka Žagar
** NAME OF ESA PECS PROGRAMME MANAGER: Maite Trujillo
DIV:
DIRECTORATE:
** ESA BUDGET HEADING:
* Sections to be completed by ESA
** Information to be provided by ESA PECS Programme Manager
