Archival and Analysis of Sea Ice Thickness in the Arctic Ocean Based on On-Ice In Situ Historical Measurements

Scientists have been conducting research on sea ice thickness in the Arctic Ocean for over a century. Sea ice thickness is perhaps the single most important observation of sea ice, as it provides an integrated record of heat flux in the air-sea-ice system. The methods to obtain thickness have evolved from using ice drills to upward-looking sonar carried on submarines to aircraft and satellite-based remote sensing methods. In-situ measurements of sea ice thickness are the most accurate, and while limited in extent, continue to be obtained for calibration of electronic and remote sensing instrumentation. If compiled, in situ measurements would also represent the longest climate record of sea ice thickness. A project was started at the Jet Propulsion Laboratory to compile in situ on-ice measurements of sea ice thickness into a database that can be used to analyze the change in sea ice thickness over the range of more than one hundred years. In addition to ice thickness, coincident measurements of snow depth and ice freeboard are also included. Both historical and contemporary records are included, from areas primarily located within the Arctic Ocean. The data are being compiled in Excel spreadsheets saved in a standard text format and then also imported to Google Earth through KML programming to gain a more complete picture of the measurement locations within the Arctic Ocean. A seasonal correction program has been applied to enable comparisons with the submarine and satellite data. A graphical user interface designed in Matlab will be used to derive various statistics. When completed, this database will serve as a sea ice climate record and can be used to examine trends with current and past measurements as the Arctic continues to rapidly response to a warming climate