watervulnerability

Chequamegon-­‐Nicolet National Forest Watershed Vulnerability Assessment, Eastern Region (R9)
Figure 2. Projected increase in seasonal air temperatures for WI, A1B scenario
Rainfall intensity is expected to increase. The number of days with precipitation greater than 2 inches is
expected to increase from seven days per decade to about 9.5 or 10 days per decade (Figure 4). Much of
this increase is projected to occur in spring and fall (Figure 5). The frequency of storms producing more
than 3.0 inches of rainfall in 24 hours is also expected to increase, especially in spring and fall. There will
also be a shorter snow season with less snowfall and snow depth.
The GFDL-CM2.0 model produced average annual temperatures for the historic and future periods of 4.6
0 C (40.3 o F) and 8.1 o C (46.6 o F), respectively (Table 1). Average annual precipitation was predicted to
increase by 0.8 inches or 2.6 percent from 31.1 to 31.9 inches (Table 1). Average monthly precipitation
would increase by about 0.5-1.5 inches in January, March, April, and May and decrease a similar amount
in June, July, and October (Figure 6).
241 Assessing the Vulnerability of Watersheds to Climate Change