Geoscience Reference
In-Depth Information
Figure 6.12.
Mean monthly precipitation (P), precipitation minus evapotranspiration
(P-ET), and evapotranspiration (ET) for the four major Arctic-draining watersheds,
based on data from 1960 through 1989 (mm). ET is calculated as a residual from P and
P-ET (adapted from Serreze et al.,
2003a
, by permission of AGU).
a sense of the importance of land-surface processes on the hydrologic budget.
The topic has a long history, starting with Mikhail Budyko and associates in the
Soviet Union in the 1950s. Notable studies include K. Brubaker, D. Entekhabi, and
P. Eagleson (
1993
), E. Eltahir and R. Bras [
1996
), and Trenberth (
1998
). Estimates
of the recycling ratio are contingent on the size of the region considered. The ratio
is smaller for areas of limited extent and increases for larger regions. Obviously, all
precipitation is recycled at the global scale.
Serreze et al. (
2003a
) examined monthly precipitation recycling for four areas
with identical area and shape. The four regions are bounded by 50°N and 70°N
latitude and each span 25°E longitude bands from 60-85°E (west-central Eurasia),
