Development of a method to derive global snow cover parameters based on 1km remote sensing data

• Applicant: Dr. Andreas Dietz
• Subject Area: Physical Geography
• Term: from 2015 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 275408816

Snow cover is one of the most crucial and sensitive land cover parameters with regards to fresh water availability, natural disasters, food security, and energy production. Climate change may lead to severe consequences with respect to the extent and duration of planetary snow cover. Therefore it is important to analyze global snow cover with high spatial and temporal resolution which will allow identifying possible trends and analyzing their impact on the hydrology and the cryosphere of a region. The aim of the project is the development of a method to derive snow cover products on the basis of remotely sensed data. To be able to detect climate relevant trends with high certainty, the project will focus on 1km Advanced Very High Resolution Radiometer (AVHRR) data. The snow cover products will be suitable to generate long term time series of global snow cover information which are crucial with respect to climate research, hydrological applications, and disaster management. Existing products reach back only until the year 2000. A reliable method to derive the global snow cover extent from optical remote sensing data at 1km resolution does not exist. The new development will allow for the generation of a long time series of snow cover data which will provide a consistent and gap free dataset of up to 30 years in combination with the already existing MODIS and GlobSnow products. Additionally, methods will be integrated to estimate the snow cover extent below clouds to allow for a gap free daily snow cover product. Studies about global or local changes of snow cover conditions will benefit from the new method: Analyses on a continental/regional scale require information about duration, start, and stop of seasonal snow cover for as long as possible. This information must be available cloud free and globally, while accuracy and resolution must be high enough to detect and evaluate the effects of climate change on this most essential part of the cryosphere. The proposed project is aiming at exactly this task. Once the methods have been developed they can be applied for any desired region to produce high quality snow cover data, which will conform to the observation requirements of satellite based products for climate of GCOS.

• DFG Programme: Research Grants