This product is one of a set of mapped model simulation results
generated for a project called "Global Climate Change and
California: Potential Implications for Ecosystems, Health, and the
Economy". The project was conducted by the Electrical Power
Research Institute (EPRI) and funded by the California Energy
Commission's Public Interest Energy Research (PIER) Program. The project
was the most detailed study ever undertaken on the potential effect of
climate change on California. The work examined a broad array of
potentially affected sectors as well as the interactions between climate
change and increased population, economic growth, and technological
change. It considered a wide range of climate change scenarios, ranging
from warmer and much wetter to warmer and much drier (http://www.energy.ca.gov/pier/project_reports/500-03-058cf.html).
Lenihan et al. used a dynamic general vegetation model (MC1),
which estimated both the distribution and the productivity of
terrestrial ecosystems such as forests, grasslands, and deserts at a
scale of 100 km2 (39 square miles), the highest resolution at which a
dynamic model had been applied in California. They estimated that under
all climate change scenarios, forests and other types of vegetation will
migrate to higher elevations as warmer temperatures make those areas
more suitable for survival. For example, with higher temperatures, the
area of alpine and subalpine forests will be reduced as evergreen
forests and shrublands migrate to higher altitudes. They estimated that
if it gets wetter, forests would expand in northern California and
grasslands would expand in southern California. If it gets drier, areas
of grasslands would increase across the state. Both wetter and drier
scenarios resulted in increases in carbon storage (biomass) in
California vegetation of between 3% and 6%. Wetter conditions generally
allow for more biomass. Under drier conditions, grasslands, which store
a relatively high amount of carbon below ground, expand.
Lenihan et al. found that the frequency and the size of fires
would increase under most scenarios; however, the change is not
significant until the latter part of the century. The drier scenarios
result in more frequent fires and more area consumed by fires. The
wetter scenarios result in fires of greater intensity than those in the
dry scenarios because more fuel (vegetation) would grow when it is wet
to be consumed by fire during occasional dry periods. This map shows
the projected percentage change in mean annual fire-consumed biomass for
the future 2070-2099 period relative to the historical 1971-2000 period.
The climate scenario was generated by the Geophysical Fluid Dynamics
Lab's General Circulation Model forced with the A2 emission scenario
(i.e., CO2 atmospheric concentration at 826 ppm by 2100).