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ACCU- Clouds

Project name:ACCU-Clouds - Preparing a Key Dimension of ACCURATE Climate Utility: Cloud Sensing and Greenhouse Gas Profiling in Cloudy Air
Project leader:Gottfried Kirchengast
Project team:

Gottfried Kirchengast
Susanne Schweiter
Veronika Proschek

Partners:Prof. Peter Bernath (expert spectroscopy), Dept of Chemistry, Univ. of York, York, UK
Dr. Claudia Emde (expert clouds), Meteorological Institute, Univ. of Munich, Munich, DE
Prof. Robert Kursinski (expert microwave occultation), Inst. of Atmospheric Physics, Univ. of Arizona, Tucson, AZ, USA


FFG-ALR (Austrian Research Promotion Agency- Aeronautic and Space Agency)



The satellite mission concept ACCURATE enables joint atmospheric profiling of greenhouse gases, thermodynamic variables, and wind in the upper troposphere and lower stratosphere (UTLS) and beyond. It achieves this unprecedented scope by employing inter-satellite signal links between Low Earth Orbit (LEO) satellites, combining LEO-to-LEO microwave occultation with LEO-to-LEO infrared-laser occultation (LIO). This novel concept was conceived at the WegCenter and proposed to ESA in the context of next Earth Explorer Missions. While not selected for formal phase A study so far, since considered not fully fitting yet from the technical and programmatic side, it received very positive evaluation and was recommended for further study and development.

On this basis FFG-ALR has since 2006 supported the pioneering initial projects /link\{ACCURAID\} and /link\{EOPSCLIM) and ESA subsequently the projects /link\{ACTLIMB\} and /link\{IRDAS\}. ACCU-Clouds builds on these activities as an innovative project complementing these predecessor studies in the key dimension of providing cloud sensing and cloudy-air greenhouse gas profiling capabilities.

Related to assessing the potential of such capabilities for climate change monitoring and research, ACCU-Clouds prepares novel scientific algorithms for retrieving cloud layering and cloudy-air greenhouse gas profiles from LIO data. These algorithms are seamlessly embedded into WegCenter’s occultation software system (EGOPS), generally used to integrate new occultation simulation and retrieval developments in an end-to-end framework. Furthermore, in order to test the advanced system, an end-to-end performance analysis is undertaken which uses the new cloudy-air greenhouse gas profiling capability to assess its utility for climate science. Results show that the detection of clouds works in a highly reliable way and that greenhouse gas concentrations are accurately derived in all conditions not blocked by clouds. Overall ACCU-Clouds contributes a crucial milestone on the way towards realizing an ACCURATE mission for the benefit of monitoring the changing atmospheric composition and climate in the 21st century.

Univ.-Prof. Mag. Dr.rer.nat.

Gottfried Kirchengast

Phone:+43 316 380 - 8431

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