Public lands provide many ecosystem services and support diverse plant and animal communities. In order to provide these benefits in the future, land managers and policy makers need information about future climate change and its potential effects. In particular, weather extremes are key drivers of wildfires, droughts, and false springs, which in turn can have large impacts on ecosystems. However, information on future changes in weather extremes on public lands is lacking. Our goal was to compare historical (1950-2005) and projected mid-century (2041-2070) changes in weather extremes (fire weather, spring droughts, and false springs) on public lands. This case study looked at the lands managed by the U.S. Forest Service across the conterminous United States including 501 ranger district units. We analyzed downscaled projections of daily records from 19 Coupled Model Intercomparison Project 5 General Circulation Models for two climate scenarios, with either medium-low or high CO2- equivalent concentration (RCPs 4.5 and 8.5). For each ranger district, we estimated: (1) fire potential, using the Keetch-Byram Drought Index; (2) frequency of spring droughts, using the Standardized Precipitation Index; and (3) frequency of false springs, using the extended Spring Indices. We found that future climates could substantially alter weather conditions across Forest Service lands. Under the two climate scenarios, increases in wildfire potential, spring droughts, and false springs were projected in 32-72%, 28-29%, and 13-16% of all ranger districts, respectively. Moreover, a substantial number of ranger districts (17-30%), especially in the Southwestern, Pacific Southwest, and Rocky Mountain regions, were projected to see increases in more than one type of weather extreme, which may require special management attention. We suggest that future changes in weather extremes could threaten the ability of public lands to provide ecosystem services and ecological benefits to society. Overall, our results highlight the value of spatially-explicit weather projections to assess future changes in key weather extremes for land managers and policy makers.
1.Univ Wisconsin, Dept Forest & Wildlife Ecol, SILVIS Lab, 1630 Linden Dr, Madison, WI 53706 USA 2.US Fish & Wildlife Serv, 5600 West Amer Blvd, Bloomington, MN 55437 USA 3.US Forest Serv, Rocky Mt Res Stn, USDA, 240 West Prospect Rd, Ft Collins, CO 80526 USA 4.US Forest Serv, Missoula Fire Sci Lab, Rocky Mt Res Stn, USDA, 5775 Highway 10, Missoula, MT 59808 USA
Recommended Citation:
Martinuzzi, Sebastian,Allstadt, Andrew J.,Pidgeon, Anna M.,et al. Future changes in fire weather, spring droughts, and false springs across US National Forests and Grasslands[J]. ECOLOGICAL APPLICATIONS,2019-01-01,29(5)