Abstract
The British Antarctic Survey (BAS) and the Danish National Space Institute (DTU Space) coordinated an airborne campaign in the period April 13‐24, 2015 as part of ICE‐ARC project (Ice, Climate, Economics – Arctic Researchon Change). The ICE‐ARC programme is funded by the EU 7th framework programme running from 2014 to2017. Coincident laser/radar measurements over sea ice were collected in the Fram Strait, north of Svalbard and north of Station Nord. The laser measurements give information on sea ice freeboard and ridges/leads distribution, while the CryoSat‐type 13 GHz radar altimeter (ASIRAS) gives information on radar penetration into the snow. The measurements north of Greenland and Svalbard are partially a continuation of time series of sea ice changes by various airborne campaigns since 1998. Two overflights of the validation site near RV Lance were conducted on April 19 and 24, including short parallellines (mow‐the‐lawn) near the ship, and longer lines aligned with EM soundings obtained by helicopter. These data, together with NASA’s Operation IceBridge overflight of RV Lance on March 19, gives a uniquecombination of in situ measurements with airborne sensors to obtain information of snow and sea iceproperties for validation of CryoSat‐2 sea ice thickness and sea surface height.For the airborne campaign, a BAS Twin Otter (VP‐FAZ) was equipped with a laser scanner, the Airborne Synthetic Interferometer Radar System (ASIRAS), and an airborne meteorology system (MASIN) to map the sea ice and ice sheet topography together with atmospheric properties. The operations were coordinated with the Norwegian Young Sea ICE cruise (N‐ICE) organized by Norwegian Polar Institute (NPI) where observations of sea ice properties were based out of the research vessel Lance.This report is part of ICE‐ARC deliverable 1.62, and describes the data collection and the data processing carried out by DTU Space for this airborne campaign 2015 with focus on the laser and radar altimetry measurements.