D.: On the role of high latitude ice, snow, and vegetation feedbacks in the climatic response to external forcing changes

• Main Author: L. D. Danny Harvey
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1988
• Subjects: Sea ice
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.456.7234; http://faculty.geog.utoronto.ca/Harvey/Harvey/papers/Harvey (1988_Climatic_Change_ice_snow_feedbacks).pdf

Abstract. A seasonal energy balance climate model containing a detailed treat-ment of surface and planetary albedo, and in which seasonally varying land snow and sea ice amounts are simulated in terms of a number of explicit physical processes, is used to investigate the role of high latitude ice, snow, and vegetation feedback processes. Feedback processes are quantified by computing changes in radiative forcing and feedback factors associated with individual processes. Global sea ice albedo feedback is 5-8 times stronger than global land snowcover albedo feedback for a 2 % solar constant increase or decrease, with Southern Hemisphere ryosphere feedback being 2-5 times stronger than Northern Hemisphere cryosphere feedback. In the absence of changes in ice extent, changes in ice thickness in response to an increase in solar constant are associated with an increase in summer surface melting which is exactly balanced by increased basal winter freezing, and a reduction in the upward ocean-air flux in summer which is exactly balanced by an increased flux in winter, with no change in the annual mean ocean-air flux.