Highlights from a decade of Ice-Tethered Profiler measurements of the Arctic Ocean

Abstract:

Intensive sampling from drifting autonomous Ice-Tethered Profiler (ITP) systems since 2004 has brought new understanding to Arctic Ocean structure and dynamics, ocean heat and mixing processes, circulation and eddies, and seasonal characteristics of under-ice biological activity. This talk will review highlights of ITP studies, and demonstrate the value of the year-round water-column measurements extending from beneath the sea ice to 750 m depth across the major Arctic basins. ITP profiles show the detailed distribution of upper-ocean freshwater and heat content over the past decade, including the changing influence of Pacific and Atlantic-origin layers. ITPs allow for assessment of vertical fluxes of deep-ocean heat in context with the strong upper-ocean density stratification, while in the surface ocean ITPs equipped with velocity sensors provide turbulent ocean-to-ice fluxes. All upper-ocean layers exhibit a rich mesoscale eddy field, and ITP measurements also reveal an active surface-layer submesoscale flow field, with scales of a few kilometers or less. ITPs equipped with bio-optical sensors have returned the first year-round measurements under sea ice of biomass related to phytoplankton and sea-ice algae in the upper-water column, establishing important regional differences in the seasonal cycle and relationships to temperature and salinity variability.