Percent change in carbon consumed by fire between 1971-2000 and 2071-2000, as simulated by MC1 underCSIRO Mk3 A2 for the Apache-Sitgreaves study area, Arizona, USA

This map represents the percent change between 1971-2000 and 2071-2100 in the amount of carbon in biomass consumed by fire, as simulated by the model MC1 under the CSIRO Mk3 future climate projection and A2 anthropogenic emissions scenario. The range of data values is from -100.0% to +1,784.6%.  The mean value is +27.9%.  Data values are calculated as (CONSUMED(2071-2100) minus CONSUMED(1971-2000)) divided by CONSUMED(1971-2000).  CONSUMED data is from MC1 version B60.

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 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.