Sea ice altimetry

CPOM researchers use radar altimeter data from CryoSat to investigate ongoing changes in Arctic sea ice thickness and volume. Observations of sea ice volume are critical, as changes in volume impact the heat and freshwater budgets of the Arctic and have wider implications for the global climate. They also help us to improve our understanding of how sea ice behaves in terms of its mechanics, with particular emphasis on the factors that drive regional and interannual variations in ice thickness and volume.

On March 17 2018 the US National Snow and Ice Data Centre (NSIDC) called the maximum extent for the year of 14.48 million square kilometres (5.59 million square miles). This was the second lowest on record behind March 2017. The Arctic sea ice volume from CryoSat (24,160 cubic kilometres) was meanwhile just 20 cubic kilometres greater than 2017, so tied as the lowest volume of the 8-year radar altimeter record. Multi-year ice volume in March 2018 was 2,000 cubic kilometres smaller than 2017, but there was a rapid growth in first-year ice volume, with average ice thickness in the Siberian Shelf Seas 18 cm thicker than in March 2017.

As demand for information on Arctic conditions increases, CryoSat has become an essential source of information for polar stakeholders, ranging from ice forecasting services to scientists studying the effects of climate change.  CPOM provides near real time data on Arctic sea ice throughout the winter months, from near real time (NRT) CryoSat data provided directly to us from the European Space Agency.  Our sea ice data service is nationally unique and globally leading, with 454 downloads per month on average and 26,609 unique users (21% UK) since it was launched in 2015. Flagship partners include the UK Met Office and the US Naval Research Laboratory, who have assimilated our measurements to improve their model predictions of summer sea ice extent.
As part of the project, CPOM researcher Rachel Tilling has participated in sea ice fieldwork campaigns organised by the ESA and the Finnish Meteorological Institute, using a sled-mounted radar to investigate the properties of snow on Arctic sea ice.  Read Rachel’s blog about her Arctic adventures.

ESA’s CryoVEx campaign, spring 2014. Credit: Rachel Tilling

ESA’s CryoVEx campaign, spring 2014. Credit: Rachel Tilling

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Aranda sea ice research cruise, spring 2016. Credit: Rachel Tilling