Tuesday, 16 January 2007: 11:15 AM
Geoprocessing Sea Ice Datasets to Derive Climate Fields
214C (Henry B. Gonzalez Convention Center)
Two large operational data products currently exist for monitoring sea-ice thickness and mass balance changes in the Southern Ocean. These are the National Ice Center (NIC) weekly ice charts and a collection of over 20,000 in situ ship-based ice observations that form the Antarctic Sea Ice Processes and Climate (ASPeCt) Program. This paper describes the geoprocessing steps to import and compare the ice charts (polygon data) with the ship-based observations (point information) using ESRI Desktop ArcGIS tools such as its field calculator, attribute query, spatial join and dissolve tools to spatially and temporally join the datasets. The uncertainties of both datasets are also propagated through individual calculations and GIS tools. The GIS methods to derive such climate fields as sea ice extent, thickness and mass balance will also be discussed. Using a GIS in this comparison and development of climate fields provides scientists with an enabling technology to assist in better understanding the quality and inaccuracies of spatiotemporal dataset, as well as investigating the temporal and spatial variability of this climate parameter.