Airborne field campaign with ASIRAS radar, EM induction sounder and laser scanner
After the successful launch of CryoSat‐2 in April 2010, the first direct Arctic validation campaign of the satellite was carried out in the period April 15 ‐ May 8, 2011. This report describes the airborne part of the CryoSat Validation Experiment (CryoVEx) 2011, and includes; 1) Data collected with the ESA airborne Ku‐band interferometric radar (ASIRAS), coincident airborne laser scanner (ALS) and vertical photography to acquire data over sea‐ and land ice along CryoSat‐2 ground tracks. The airborne campaign was coordinated by DTU Space using the Norlandair Twin Otter (TF‐POF). 2) Sea ice thickness data obtained with an airborne electromagnetic (AEM) induction sounder conducted by Alfred Wegener Institute (AWI) with fixed‐wing airplane (Polar‐5, Basler BT‐67). DTU Space airborne team visited five main validation sites: Devon ice cap (Canada), Austfonna ice cap (Svalbard), the EGIG line crossing the Greenland Ice Sheet, as well as the sea ice north of CFS Alert (Ellesmere Island), and sea ice north off Svalbard. Selected tracks were planned to match CryoSat‐2 passes and a few of the sea ice flights out of CFS Alert were coordinated with AWI Polar‐5 carrying the AEM induction sounder and NASA’s Operation IceBridge P‐3 carrying a variety of instruments for sea ice and snow retrieval. At each validation site ground teams measured ice and snow properties, and raised corner reflectors acting as a surface reference point to estimate the penetration depth of the ASIRAS radar. This report describes in details the airborne systems, together with campaign implementation plan, data processing and data quality analysis. The CryoVEx 2011 campaign was a success and the processed data is of high quality. The datasets are very important in order to understand the CryoSat‐2 radar signals over sea‐ and land ice.