Antarctic sea ice is an important feature of the global climate system as it affects ocean-atmosphere interaction in the Southern Ocean. The mass balance of sea ice is a product of its areal extent and thickness. Of these two, thickness is the least known.

Since 1995, the National Ice Center (NIC) has been classifying and cataloguing the "stages-of-development" of sea-ice based on a subset of the World Meteorological Organization (WMO) sea-ice classification standards. This classification scheme is used as an areal proxy for ice thickness. However, to date, no systematic effort has been undertaken to validate or test this proxy information against in-situ measurements. The first goal of this project is to make use of approximately 11,000 ship-based thickness observations obtained though ASPeCt under SCAR to compare with the NIC proxy charts. Sea-ice charts of the Ross Sea are believed to be the most accurate because of the extensive aircraft reconnaissance coverage there. Hence, the Ross Sea has been selected as the first region for comparison of these two data sets with the goal of ascertaining the quality of these data in climate studies. With the quality of the charts ascertained, the second goal is to quantify how much seasonal variability can be seen using the NIC charts.