DOCUMENTING ARCTIC SEA ICE BEHAVIOR WITH HIGH-RESOLUTION GLOBAL FIDUCIALS LIBRARY IMAGERY

High resolution imagery is critical to document Arctic sea ice response to climate change. The U.S. Geological Survey Global Fiducials Library (GFL) hosts >1,750 ~1-m resolution Arctic sea ice literal imagery derived products (LIDPs) collected by U.S. National Imagery Systems (USNIS) sensors. The LIDPs, derived from USNIS images are available at gfl.usgs.gov for free, unrestricted, public distribution and use.

Space-based monitoring of Arctic sea ice began in 1978 with the launch of NASA’s Scanning Multichannel Microwave Radiometer. Twenty-two years later, high-resolution satellite imagery time series from the Surface Heat and Energy Budget of the Arctic (SHEBA) Experiment, were released to depict and document increased melting and the formation of extensive ice-surface melt ponds in response to accelerating climate change.

In 1997-1998, images were collected with USNIS sensors to document SHEBA, in which an icebreaker was frozen into the sea ice for more than 400 days, to directly observe the effects of climate change on ice dynamics as the icebreaker and the adjacent ice drifted across the Beaufort Sea. In 2000, ~100 LIDPs were publicly released.

In 1999, new collections of USNIS imagery of six static sea ice sites in the Arctic Basin began, with imagery archived in the GFL. Each site was periodically imaged for up to 15 years, creating time series of geographically referenced LIDPs that document seasonal changes in Arctic sea ice at the 6 sites.

Between 2009 and 2014, to improve understanding of seasonal changes, the USGS tracked and imaged sea ice floe movement during entire Arctic summer periods. To repeatedly image the same ice, the USGS developed a methodology that used data from ice-emplaced telemetering buoys to track sea ice drift for periods exceeding a year. The resulting sea ice imagery time series, captured while monitoring 38 individual buoys, are archived in the GFL.

In 2013-2014, USNIS imagery collected of sites located at every degree of latitude between 70^o N. and 80^o N., along north-south transects in the Beaufort and Chukchi Seas, was used to support the Seasonal Ice Zone Reconnaissance Surveys (SIZRS) Program. This was done to track and understand the interplay among the ice, atmosphere, and ocean, contributing to the on-going rapid decline in summer ice extent. This imagery is also available from the GFL.