Main Page
Research
Image Gallery
People
Student Opportunities
Outreach
Publications
Teaching
Contacts
Links
Field Blogs
Barrow Ice Observatory

Coastal Ice Research

Mapping and Characterization of Recurring Spring Leads and Landfast ice in the Beaufort and Chukchi Seas
The aim of this project is to map and document changes in the spatial and temporal distribution of recurring lead systems and coastal polynyas off the coast of northern Alaska in the Chukchi Sea between Wainwright and Barrow and the Beaufort Sea between Barrow and the Mackenzie River Delta. mms.gina.alaska.edu

The Energy and Mass Balance of Coastal Ice Covers in Northern Alaska
Significant change has been observed in sea-ice conditions along the northern coast of Alaska. These changes could represent alterations in the proportion of sunlight reaching the surface, in the quality and quantity of back radiation into the atmosphere from the surface, or in changes in heat content of land and coastal seas. To provide basic information about the radiation inputs, losses, and heat fluxes, 4 sites near Barrow Alaska have been established for detailed monitoring of solar and atmospheric heat fluxes as experienced by snow, sea-ice, near-surface waters, and land. The goal is to establish the local heat budgets, seasonal timing of key thermal events (snow melt, sea-ice melt, freezing onset, etc), and feedback mechanisms. Apart from these sites, the approach comprises transect line sampling on frequent useful intervals to obtain spatial averages and variability, and aircraft sampling and satellite data to evaluate larger scale conditions in the vicinity of Barrow.

Alaskan Landfast Sea Ice Dynamics
This is the working title of Andy Mahoney's PhD thesis. By definition, landfast ice remains stationary and attached to the coast for most of the year. However, it is shaped by dynamic events throughout its seasonal existence between formation in late fall and break-up in spring. Using a combination of satellite and ground-based remote sensing, together with field observations, I am attempting to understand the mechanisms by which the landfast ice responds to the forces of ocean currents, tides and winds. Such a study must incorporate the different scales at which these processes act.
At the regional scale, 8 years of Radarsat Synthetic Aperture Radar (SAR) imagery is being used to delineate the seaward landfast ice edge (SLIE) as it evolves through the different seasons (see Mapping and Characterization of Recurring Spring Leads and Landfast ice in the Beaufort and Chukchi Seas). At this scale, the SLIEs appear to resolve themselves into nodes of stability separating regions of greater variability. At the local scale, a land-based side-looking X-band marine radar is employed to scan landfast ice within approximately 5 km of Barrow, Alaska every 5 minutes (see Barrow Sea Ice Observatory). This high temporal resolution captures ice dynamics during the creation of grounded ridges. These ridges can be built in less than an hour and remain for the entire season, before breaking up and drifting away as swiftly as they arrived. At the highest spatial resolution, field observations using a Differential Global Positioning System (DGPS) and an electromagnetic induction device are combined to measure sea ice elevation and thickness nearly continuously along transects within the land-based radar footprint from the beach at Barrow to the SLIE. These transects are intended to locate and determine the size of grounded ridges, which surely play an important role in holding the ice cover fast to the coast.
In addition to examining processes across spatial scales, we are also looking at previous data collected on the landfast ice, mainly during the Outer Continental Shelf Environmental Assessment Program (OCSEAP) years in the 1970s, to examine evidence for changes in the landfast ice regime. By comparing the regimes of the landfast ice and the larger scale atmospheric circulation and sea ice distribution, we hope to identify processes responsible for any change.

back to Research