Two years with extreme and little snowfall: effects on energy partitioning and surface energy exchange in a high-Arctic tundra ecosystem

The Cryosphere Discussions

Lindroth, Anders¹  Christensen, Torben Røjle¹  Stiegler, Christian²  Lund, Magnus²  Mastepanov, Mikhail² 

[1] Arctic Research Centre, Department of Bioscience, Aarhus University, Roskilde, Frederiksborgvej 399,4000 Roskilde, Denmark;Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sölvegatan 12, 223 62 Lund, Sweden

DOI  :  10.5194/tc-10-1395-2016

学科分类：地球科学(综合)

来源: Copernicus Publications

【 摘 要 】

Abstract. Snow cover is one of the key factors controlling Arctic ecosystem functioning and productivity. In this study we assess the impact of strong variability in snow accumulation during 2 subsequent years (2013–2014) on the land–atmosphere interactions and surface energy exchange in two high-Arctic tundra ecosystems (wet fen and dry heath) in Zackenberg, Northeast Greenland. We observed that record-low snow cover during the winter 2012/2013 resulted in a strong response of the heath ecosystem towards low evaporative capacity and substantial surface heat loss by sensible heat fluxes (H) during the subsequent snowmelt period and growing season. Above-average snow accumulation during the winter 2013/2014 promoted summertime ground heat fluxes (G) and latent heat fluxes (LE) at the cost of H. At the fen ecosystem a more muted response of LE, H and G was observed in response to the variability in snow accumulation. Overall, the differences in flux partitioning and in the length of the snowmelt periods and growing seasons during the 2 years had a strong impact on the total accumulation of the surface energy balance components. We suggest that in a changing climate with higher temperature and more precipitation the surface energy balance of this high-Arctic tundra ecosystem may experience a further increase in the variability of energy accumulation, partitioning and redistribution.

.

【 授权许可】

CC BY