GeoData Center Project: Greenland Melt Data and 1km DEM

Surface melting on the Greenland Ice Sheet is an important indicator of Arctic terrestrial climate change much as the observations of dwindling Arctic sea-ice document climate change over the polar ocean. Most surface melt studies are conducted using satellite based observations. The longest continuous time-series of satellite measurements available for Greenland is from passive microwave sensors (since December 1972). More recently higher resolution scatterometer and optical data are complementing the passive microwave data set.

Here, we provide annual estimates of surface melt extent of the Greenland Ice-Sheet from Scanning Multichannel Microwave Radiometer (SMMR, 1979-1987) and Special Sensor Microwave Imager (SSM/I, 1987-2008). We have used a wavelet-based edge detection technique for melt detection.

We have also calculated surface melt from Quick Scatterometer (QuikSCAT, 2000-2008) to provide independent comparison and validation of the calculated melt area from passive microwave.

Here we are providing the annual total melt-area extent calculated from passive microwave and QuikSCAT. We are also providing annual sector-by-sector melt-area data (calculated from passive microwave). For delineation of sector, refer to Bhattacharya et al. [2009].

All the data is provided in ASCII format.

For detailed description of our methodology and results please refer to the published journals. For any further question please contact bhattacharya.21@gmail.com or jezek.1@osu.edu

Available DEMs of the Greenland Ice Sheet are based on satellite radar altimetry data (e.g. Bamber, Ekholm,and Krabill 2001) Article, or on the combination of radar altimetry data and AVHRR imagery by using photoclimometry techniques to fill the regions between radar orbits (Scambos and Harran) Link to Abstract (referred to as 'available DEMs').

Elevation errors of these DEMs range from a few meters at the middle of the ice sheet (>2000m elevation) to 50-100m in marginal regions.

The objective is to improve the accuracy of these 'available DEMs' by using 3/20/03 - 6/23/05 ICESat satellite laser alimetry data, 1999-2003 Airborne Topographic Mapper (ATM) laser altimetry data (Krabill, NASA WFF) Article, and KMS landcover map of Greenland.