The role of vegetation feedbacks on Greenland glaciation

• Published in: Climate Dynamics
• Main Authors: Stone, Emma J, Lunt, Daniel J
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2013
• Subjects: vegetation; Greenland; Ice Sheet
• Online Access: https://hdl.handle.net/1983/cef575bc-88f4-4428-a4fe-3251bdb181a8; https://research-information.bris.ac.uk/en/publications/cef575bc-88f4-4428-a4fe-3251bdb181a8; https://doi.org/10.1007/s00382-012-1390-4; http://link.springer.com/article/10.1007%2Fs00382-012-1390-4

The role of vegetation feedbacks for the process of ice-sheet evolution could potentially be important in realistically modeling the past and future evolution of the Greenland ice-sheet. We use a fully coupled atmosphere–ocean model to assess the response of the climate when the Greenland ice-sheet is replaced with a number of fixed vegetation types (bare soil, broadleaf and needleleaf trees, C3 and C4 grasses and shrubs) in conjunction with loaded and unloaded bedrock orography. These sensitivity experiments show that albedo changes dominate the climate response during the summer months while temperature changes during winter are attributed to altitude change and changes in atmospheric circulation over Greenland. Snow-free summers occur for all fixed vegetation types, except for high altitude eastern regions for bare soil. We perform further simulations with dynamic vegetation resulting in dominant shrub coverage over central and southern Greenland with grasses supported in the north. Ice-sheet modeling shows significant regrowth of the Greenland ice-sheet can occur for a bare soil surface type, dependent on ice-sheet model parameters, while Greenland remains almost ice-free for needleleaf tree coverage. Furthermore, a realistically vegetated Greenland can only support a small amount of ice-sheet regrowth implying multi-stability of the Greenland ice-sheet under a preindustrial climate. This study highlights the importance of considering vegetation climate ice-sheet interactions, and uncertainty in ice-sheet model parameters.