Publication Date:
2014-11-08
Description:
Long term effects on regional European boreal climate due to structural vegetation changes Biogeosciences Discussions, 11, 15507-15547, 2014 Author(s): J. H. Rydsaa, F. Stordal, and L. M. Tallaksen Amplified warming at high latitudes over the past decades has led to changes in the boreal and arctic climate system, such as structural changes in high latitude ecosystems and soil moisture properties. These changes trigger land-atmosphere feedbacks, through altered energy partitioning in response to changes in albedo and surface water fluxes. Local scale changes in the arctic and boreal zone may propagate to affect large scale climatic features. In this study, MODIS land surface data are used with the Weather Research and Forecasting model (WRF V3.5.1) and Noah LSM, in a series of experiments to simulate the influence of structural vegetation changes over a Northern European boreal ecosystem. Emphasis is placed on surface energy partitioning and near surface atmospheric variables, in order to investigate changes in atmospheric response due to observed and anticipated structural vegetation changes. We find that a northward migration of evergreen needle leaf forest into tundra regions causes an increase in latent rather than sensible heat fluxes, increased near surface temperatures and boundary layer height. Shrub expansion in tundra areas has only small effects on surface fluxes. However, it influences near surface wind speeds and boundary layer height. Northward migration of mixed forest across the present southern border of the boreal forest has largely opposite effects on surface fluxes and the near surface atmosphere, and acts to moderate the overall mean regional effects of boreal forest migration on the near surface atmosphere.
Print ISSN:
1810-6277
Electronic ISSN:
1810-6285
Topics:
Biology
,
Geosciences
