Simulated understory
index (fraction of grass vegetation carbon in forest, ((aglivcx + bglivcx) /
frstc))) averaged over 2076-2095 simulated by the MC1
dynamic global vegetation model (Bachelet et al. 2001) at a 800 m x 800 m spatial
resolution using future climate projections provided through CMIP3 (http://www-pcmdi.llnl.gov/ipcc/about_ipcc.php).
Future climate drivers were generated using statistical
downscaling (simple delta method) of general circulation model projections, in
this case Hadley CM3 (Johns et al. 2003) under the A2 emission scenario (Naki?enovi?
et al. 2000). The deltas (differences for temperatures and ratios for
precipitation) were used to modify PRISM 800 m historical baseline (Daly et al.
2008).
Note: The MC1 model is described in data basin (http://databasin.org/climate-center/features/mc1-dynamic-global-vegetation-model).
References:
Bachelet
D., R.P. Neilson, J. M. Lenihan, and R.J. Drapek. 2001. Climate change effects
on vegetation distribution and carbon budget in the U.S. Ecosystems 4:164-185.
Daly, C., M. Halbleib, J.I.
Smith, W.P. Gibson, M.K. Doggett, G.H. Taylor, J. Curtis, and P.A. Pasteris.
2008. Physiographically-sensitive mapping of temperature and precipitation
across the conterminous United States. International Journal of Climatology 28:
2031-2064.
Johns, T.C., J.M. Gregory, W.J.
Ingram, C.E. Johnson, A. Jones, J.A. Lowe, J.F.B. Mitchell, D.L. Roberts,
D.M.H. Sexton, D.S. Stevenson, S.F.B. Tett, and M.J. Woodage. 2003.
Anthropogenic climate change for 1860 to 2100 simulated with the HadCM3 model
under updated emissions scenarios. ClimDyn 20: 583-612.
Naki?enovi?, N. and R. Swart,
Eds. 2000. Emissions Scenarios: A
Special Report of Working Group III of the Intergovernmental Panel on Climate
Change. Cambridge Univ. Press, Cambridge, U. K.