The Impact of Reduced Arctic Sea Ice Extent on Cryospheric Snowfall

Authors

Alexander Carne, University of Nebraska-LincolnFollow

First Advisor

Dr. Mark Anderson

Date of this Version

Fall 12-11-2017

Document Type

Article

Citation

Carne, A. R., 2017: The Impact of Reduced Arctic Sea Ice on Cryospheric Snowfall. M.S. Thesis, Department of Earth and Atmospheric Sciences, University of Nebraska-Lincoln.

Comments

A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Geoscience,s Under the Supervision of Professor Mark Anderson. Lincoln, Nebraska: August, 2017

Copyright © 2017 Alexander R. Carne

Abstract

Satellite observations show that sea ice extent in the Arctic has been declining from 1979 through present day, reaching record minimum extents in 2007 and 2012. Reduced sea ice extent allows for greater expanses of open water to interact with the Arctic atmosphere, potentially leading to changes in the Arctic climate. The greatest declines in Arctic sea ice extent have occurred in summer and autumn. During these seasons, it is likely that the decrease in Arctic sea ice extent led to an increase in atmospheric sensible and latent heat fluxes, possibly leading to increases in Arctic temperature and moisture. Increases in atmospheric temperature and moisture would likely impact Arctic precipitation patterns, and if the temperature is cold enough, snowfall would be impacted as well. Investigations into the impact of reduced sea ice extent on Arctic snowfall has been conducted over seasonal time scales, however, a lack of attention has been given to the influence of reduced Arctic sea ice extent on snowfall within individual cyclones. This study examines the impact of reduced Arctic sea ice extent on snowfall produced within individual Arctic cyclones through a reanalysis study. The autumnal months of October and November are examined for the years 1982 and 1985, years that possess normal to above normal sea ice extents compared to 2007 and 2012, years that possess below average sea ice extents. Additionally, monthly snowfall and snow depth are examined to provide a comparison of the seasonal scale snowfall patterns during October and November of the four years. Data for analysis are produced by running the Weather Research and Forecasting Model (WRF) utilizing the European Center for Medium Range Weather Forecasting (ECMWF) ERA-Interim reanalysis dataset in an Arctic domain. Results indicate that locations along the Arctic coast, along with ice-covered regions near the sea ice margin, have the greatest potential for increased snowfall and snow depth from high-latitude cyclones. The results also suggest that monthly snowfall increases over the Arctic Ocean in October with reduced Arctic sea ice, leading to an increase in snow depth over existing multi-year sea ice in years with below average sea ice extents.

Advisor: Mark R. Anderson