1. Sea ice thickness from airborne laser scanning Sine M. Hvidegaard, Rene Forsberg, Henriette Skourup, and others

2. 2DTU Space, Technical University of Denmark 19th April 2008 Red: airborne laser flight Blue: In situ observations West Greenland 2008

3. 3DTU Space, Technical University of Denmark Validation of sea ice freeboard to thickness 1 2 3 4 5

4. 4DTU Space, Technical University of Denmark SitePositionIn Situ observation Area mean from scanner, 40x40 m HE372.790N 57.52818W0.80 m HE472.790N 58.08628W1.07 m1.65 m HE572.790N 58.59538W1.03 m1.38 m HE672.790N 58.97913W0.88 m1.08 m HE772.790N 59.53297W1.07 m0.70 m HE872.790N 59.81628W0.38 m0.69 m Calibration of thickness using in situ obs.

5. 5DTU Space, Technical University of Denmark Existing data 2002-2008 Baffin Bay 2006 and 2008 data calibrated with use of in situ data from drillings (helicopter landings) 2002-2004 data based on climatology All data is collected in early to mid May

6. 6DTU Space, Technical University of Denmark Existing data 1998- East Greenland 2.5 m (0-5 m) April 2008 1998-2006

7. 7DTU Space, Technical University of Denmark Mean sea ice thickness 1993-2001 Only based on radar altimetry from winter (October – March) Thin ice is not included Similar observations with higher accuracy and spatial reolution will be available from CryoSat (launched April 2010) Validation campaign planned for April- May 2011 (Greenland, Arctic Ocean and Svalbard) 2-2.5 m 3.5-4.5 m S. Laxon, Nature 2003 Havis tykkelser set fra satellit - radar CryoSat