CoAuthors

Ernst Schrama (TU Delft, Netherlands); Jerome Bouffard (ESRIN-ESA, Italy)

The ESA’s Earth Explorer CryoSat-2 mission is dedicated to precise measurement of the changes in the thickness of marine ice floating on the polar oceans and variations in the thickness of the vast ice sheets that overlie Greenland and Antarctica. With the effects of a fast-changing climate becoming apparent, particularly in the Polar Regions, it is increasingly important to understand exactly how Earth’s ice fields are responding. Diminishing ice cover is frequently cited as an early casualty of global warming and since ice plays an important role regulating climate and sea level, the consequences of change are far-reaching. To understand fully how climate change is affecting these remote but sensitive regions, there remains an urgent need to determine exactly how the thickness of the ice, both on land and floating in the sea, is changing. By addressing this challenge, the data delivered by the CryoSat-2 mission completes the picture and leads to a better understanding of the ice role in the Earth system. In order to achieve this, the quality of the orbit, the measurements of the altimeter, and all required corrections have to meet the highest performance, and this not only over the ice caps and sea-ice surface but also over the oceans.

The objective of our research is the long-term analysis and validation of the CryoSat-2 ocean data. This entails assessing the long-term quality and stability of Level-2 GOP parameters when compared to concurrent in situ data from e.g. tide gauges, when compared to relevant numerical ocean models and when compared to other altimeter data sets through the use of RADS. It also entails assessing the impact of using alternative orbit solutions in terms of long-term quality, stability and consistency of Level-2 GOP geophysical parameters when compared to other reference altimeter data sets and Fiducial Reference measurements. We will present preliminary results of this research.