CoReH2O Snow Retrieval Study (2009-2011)

Development of Snow Retrieval Algorithms for CoReH2O. ESA Study, Prime Contractor ENVEO, Contract 22380/09/NL/JC.

The Cold Regions Hydrology High-Resolution Observatory (CoReH₂O) mission has been selected as one of the candidate Earth Explorer missions for studies of technical and scientific feasibility and consolidation at Phase A level. The CoReH₂O mission aims to close gaps in spatially detailed observations of key parameters of the global snow and ice masses for applications in climate research and hydrology. The proposed technical solution relies on a dual frequency, X- and Ku-band (9.6 and 17.2 GHz), dual-polarized (VV and VH) synthetic aperture radar. The scientific objectives of the mission are to address snow and ice processes over different temporal and spatial scales. This is taken into account by two different temporal observation phases. The first mission phase will employ a 3-day repeat orbit for snow and ice observations matching the time scale of typical mid- and high-latitude weather systems. The second mission phase will deliver near-complete observations of the global snow and ice-covered areas at a repeat cycle of about two weeks.

Primary and secondary geophysical observation parameters have been defined. The primary parameters, to be delivered by the mission as Level 2 products, are the extent of snow areas and snow water equivalent (SWE) over land sufaces, and the winter snow accumulation on glaciers.

The main objective addressed by this project is the development, testing and documentation of consolidated algorithms and processing lines for the retrieval of the primary geophysical parameters from CoReH₂O Level 1 products. The use of experimental data from satellite sensors and campaigns, as well as simulated data will be essential for testing and validating the algorithms. Software development will be performed for the selected retrieval algorithms and thorough test and performance analysis will be conducted. In addition, a synthetic scene generator will be implemented in order to compile representative input cases for test and validation of the retrieval algorithms and processing lines.

ENVEO has assembled a strong team of institutions and scientists very experienced in SAR processing and applications, radar interactions with snow and ice, and retrieval techniques.

Objectives

• identification and evaluation of effects of target and environmental properties on the backscatter signal and snow products;
• development of retrieval methods for SWE and snow accumulation;
• testing and validating the algorithms using experimental data from satellite sensors and campaigns, as well as simulated data;
• definition of test scenarios for performance analysis;
• performance analysis of retrieval algorithms;
• implementation of retrieval algorithm and synthetic scene generator;