Microclimate at Arctic Tree Line 3. The Effects of Regional Advection on the Surface Energy Balance of Upland Tundra

Energy balance components of net radiation, ground heat flux, and latent and sensible heat fluxes for upland tundra near the Hudson Bay coast at Churchill were measured continuously between April 25 and September 6, 1979. The measurements indicate a strong regional advective effect. In the premelt period during cold onshore winds, net radiation was very small and the other energy balance components were negligible. Under offshore warmer winds, net radiation was large, as were the other fluxes, especially the ground heat flux. In the postmelt period with cold onshore winds, sensible heating of the atmosphere was large and heating of the ground was suppressed. For offshore winds, ground heating was large and atmospheric heating was suppressed. The magnitude of net radiation and the latent heat flux were little affected by wind direction in the postmelt period. The implications of the results are discussed with respect to the potential effects of climatic cooling and warming.

Microclimate at Arctic Tree Line 3. The Effects of Regional Advection on the Surface Energy Balance of Upland Tundra Journal Articles