Evaluation of CryoSAT-2 for height retrieval over the Himalayan range
Résumé
Climate warming over the 20th century has caused drastic changes in mountain glaciers globally, and of the Himalayan glaciers in particular. The stakes are high; mountain glaciers are the largest contributor to the increase in the mass of the world's oceans, and the Himalayas play a key role in the hydrology of the region, impacting on the economy, food safety and flood risk to a large population. Partial monitoring of the Himalayan glaciers has revealed a mixed picture; while many of the Himalayan glaciers are retreating, in some cases locally stable or advancing glaciers in this region have also been observed. Recent controversies around the future of the Himalayan glaciers, fuelled by projections reproduced in the 2007 Intergovernmental Panel on Climate Change report, have highlighted our limited knowledge of the evolution of Himalayan glaciers, and our limited understanding of the relationship between climate change and Himalayan glaciers' change. In its interferometric mode, CryoSat-2 is designed to enable the retrieval of elevation over steep sloping terrain. If successful over mountain glaciers, height retrieval by CryoSat-2 could provide an invaluable datasets for the assessment of ice mass balance of the Earth's mountain glaciers. Here we present the first results of quality assessment of height retrieval by CryoSat-2 over the snow and ice covered Himalaya.