AON: Sustained observation and study of the rapidly evolving Arctic Ocean environment

Climate models predict that the Arctic will experience the greatest amount of warming on the planet in the coming decades. Seemingly consistent with those modeling results, Arctic sea ice extent and total volume have decreased markedly since the turn of the century. The expanded areas of the sea surface exposed to the atmosphere in summer are warming and ocean currents are carrying that heat below the ice-covered regions to drive additional ice melting from below.

Sustained observations of the rapidly-evolving Arctic Ocean are vital for documenting ongoing changes and exploring the responsible mechanisms, research that will ultimately lead to improved ability to forecast the future state of the Arctic. This award will support annual deployments of autonomous, expendable instrument systems (called Ice-Tethered Profilers, ITP) that sample and report in real time the sea water temperature and salinity of the upper ocean as the buoys drift with their supporting sea ice floes, continuing an observational record initiated in 2004.

These data have proven to be a valuable resource for scientific research, student projects, and operational forecasting; to date, approximately 275 research papers have been published and numerous student dissertations written that have utilized ITP data. Over the duration of this 5-year award, a total of 18 ITP systems will be constructed, tested and deployed in the Arctic on cruises of opportunity with the resulting data being made publicly available and preserved in national data archives.

Improved forecast skill based on these and other polar observations will allow more efficient planning for resilient coastal infrastructure, fishery and resource extraction, navigation, search and rescue activities and defense systems.

Begun in 2004, the Ice-Tethered Profiler program has annually fielded instrument systems distributed throughout the deep Arctic that return year-round daily vertical profiles of sea water temperature and salinity, and other water properties at sub-meter vertical resolution over depths of ~5 m to ~750 m as the buoys drift with their supporting ice floes. A new variant of the ITP, the Tethered Ocean Profiler, TOP, focuses on waters from ~200 m depth up to within 15 cm of the ice-ocean interface.

The present award will continue and improve the ITP/TOP observing program for another 5-years. A three-pronged effort is planned to consist of (1) annual deployments of operational ITPs and TOPs from Arctic cruises of opportunity and dissemination of the resulting data, (2) ongoing engineering efforts to keep abreast of the evolving supply chain for ITP/TOP components, and (3) quality control and scientific analysis of the resulting data with results published in peer-reviewed journals.

Data from these autonomous instruments will be publicly distributed via the project website, the Global Telecommunications System (GTS) network, the Arctic Data Center, and the National Centers for Environmental Information.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.