Polar Climate System
October 26, 2012 15:25:33
Description of Problem
A polynya is a persistent opening or hole in sea ice that occurs in locations or times when sea ice is otherwise thought to be present. They come in many different shapes and can range in size from hundreds to thousands of square kilometers. Even though their relatively small size in comparison so the sea ice itself, polynyas have a large impact on the Arctic in a number of ways. Polynyas affect the surrounding atmosphere, the radiation budget, the local ocean salinity, the ocean circulation, and wildlife. In the winter months their effects are most prominent. They provide the surrounding air with excess heat and moisture, which cools the ocean and heats up the surrounding boundary layer. This excess moisture leaves the ocean surface, quickly cools and condenses, and creates plume clouds, which can be transported downstream via winds. Polynyas are relatively under sampled due to their remote locations and harsh wintertime conditions. Observations are done on field campaigns, on ships and by weather stations, but data is collected for short time periods and instrument error can occur due to harsh conditions.
In the past decade there has been an abundance of satellite data that has spatial and temporal scales that provide much more coverage of the Arctic and polynyas than field campaigns. Being able to use this valuable data to study polynyas in detail would greatly enhance our understanding of polynyas and their effects on the Arctic system.
Scientific Objectives and Approach
I am currently using data from the NASA AQUA satellite (specifically AIRS, MODIS, and AMSR-E) to study polynyas from 2003-2009 in detail. I am looking at daily values such as surface air temperature, temperature profiles, surface skin temperature, sea surface temperature, ice concentration, and relative humidity profiles from these sensors. In order to study the polynyas on a short time scale I will look at level 2 orbital data to get observations multiple times a day and study how the polynyas behave over short time scales. Looking at short time scales I hope to be able to see plume formation and movement from the polynyas. I will also compare my results to model results of polynyas to see how they compare.
Refereed Journal Publications
Kurtz, N., T. Markus, S. Farrell, D. Worthen, and L. Boisvert (2011), Observations of recent Arctic sea ice volume loss and its impact on ocean-atmosphere energy exchange and ice production, J. Geophys. Res., doi:10.1029/2010JC006235, in press.
Other Publications and Conferences
Markus, T., L. Boisvert, J. Miller, J. Stroeve, and C. Parkinson, ‘Changes in sea ice melt and freeze-onset derived from satellite passive microwave data and its interactions with sea ice concentration, and ocean and atmosphere temperatures’. the 2010 IEEE International Geoscience and Remote Sensing Symposium (IGARSS)
Boisvert, L., T. Markus, and C. Parkinson, ‘Sea Surface Temperatures and their Relationship to Melt and Freeze Onset in the Central Arctic’. 2010 Fall American Geophysical Union (AGU)