Change in the mean annual fraction of cell burned between 1971-2000 and 2070-2099, as simulated by MC1 under Hadley A2 for the Apache-Sitgreaves study area, Arizona, USA

This map represents the change between 1971-2000 and 2070-2099 in the mean annual fraction of each gridcell affected by fire, as simulated by the model MC1 under the Hadley future climate projection and A2 anthropogenic emissions scenario. Data values are calculated as PART_BURN(2070-2099) minus PART_BURN(1971-2000).  PART_BURN data is from MC1 version B60. The average annual fraction of cell burned for the respective 30-year periods increased in some of the 5,311 grid cells of the Apache-Sitgreaves study area and decreased in others.  The range of data values is from -0.077 to +0.163.  The mean value is +0.031.


The vegetation model MC1 (e.g. Bachelet et al. 2001) was used to simulate vegetation dynamics, associated carbon and nitrogen cycle, water budget, and wild fire impacts at two study sites in eastern Oregon (Deschutes and Fremont-Winema National Forests) and in Arizona (Apache Sitgreaves National Forest area) in the context of a project funded by the USDA Forest Service (PNW 09-JV-11261900-003).
 Historical climate input data used to run the model were provided by the PRISM group (Chris Daly, OSU) at a 30arc second (800m) spatial grain.
The model was also run using future climate change projections from various general circulation models including Hadley, CSIRO Mk3 and MIROC 3.2 medres. Future climate change climate datasets were generated through statistical downscaling from general circulation model output using a simple anomaly method and the climatology (1971-2000) from the PRISM group at 30arc second spatial grain.

  The model was run assuming that nitrogen demand from the plants was always met so that the nitrogen concentrations in various plant parts never dropped below their minimum reported values. A CO2 enhancement effect increased productivity and water use efficiency as the atmospheric CO2 concentration increased.