The emerging role of the land surface in weather and climate prediction
Paul Dirmeyer
George Mason University
29 May, Noon, in 2155
Abstract:
Like the ocean, the land surface is a slowly varying manifold relative
to the atmosphere that provides predictability and prediction skill
across a range of time scales. Although the peak influence of land
surface states is in the “subseasonal” time range between 1-3 weeks,
significant impact of land, or errors in its representation, begins in
forecasts the first morning of simulation. The process chains that link
soil moisture, vegetation, snow, and other land states through the
energy and water cycles manifest though their effects on the growing
daytime boundary layer, cloud formation and convection. Thus, the
diurnal cycle is key to assessing and improving model performance
related to land-atmosphere interactions. Daily, monthly and seasonal
mean skill arising from coupled land-atmosphere feedbacks can only
improve by improving the diurnal cycle.