watervulnerability

Coconino National Forest Watershed Vulnerability Assessment, Southwest Region (R3)
Modeled Predictions
Available to the team were predictions of climate change prepared by the Climate Impacts Group (CIG)
of the University of Washington. CIG compared available predictions with historic data for the western
United States, and combined models with the best correlations to develop composite models for the
western United States (Littell et al. 2011). Downscaled data from these models were provided to National
Forests participating in the WVA pilot, including the Coconino NF. This analysis used the CIG composite
model, and predictions for 2030 and 2080. These were compared for the composite modeling of the
historic condition.
The models predict nearly-uniform air temperature increases across the Coconino NF, of about 4 degrees
F in 2030, and 7 degrees F in 2080. Modeled comparisons, by season, are displayed in Table 3. Results
for maximum July temperatures in 2030, as compared to the historic condition, are shown in Figure 13.
Season Historic 2030 2080
2030
Change
2080
Change
DJF 50.6 53.9 56.7 3.3 6.1
MAM 66.7 70.7 73.8 3.9 7.1
JJA 87.0 91.4 94.5 4.4 7.6
SON 70.6 75.0 78.3 4.4 7.8
Annual 68.7 72.7 75.9 4.0 7.1
Table 3. Results from CIG composite model for air temperature. Values are averages for the entire analysis area.
Figure 13. Results from CIG composite model projection for air temperature daily
maximum for July. Results are the difference between the 2030 and historic simulations.
143 Assessing the Vulnerability of Watersheds to Climate Change