Predicted probability of marten year-round occurrence derived
from future (2046-2065) climate projections and vegetation simulations. Projected marten distribution was created
with Maxent (Phillips et al. 2006) using marten detections (N = 302, spanning
1990 – 2011) and nine predictor variables: mean winter (January – March)
precipitation, mean amount of snow on the ground in March, mean understory
index (fraction of grass vegetation carbon in forest), mean fraction of total forest carbon in coarse
wood carbon, average maximum tree LAI, mean fraction of vegetation carbon
burned, mean forest carbon (g C m2), mean fraction of vegetation
carbon in forest, and modal vegetation class.
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 4km historical baseline (Daly et al. 1994).
Vegetation variables were simulated with MC1 dynamic global vegetation model (Bachelet
et al. 2001). This marten distribution
projection was generated as part of a pilot project to apply and evaluate the
Yale Framework (Yale Science Panel for Integrating Climate
Adaptation and Landscape Conservation Planning).
Grid Value Predicted
Probability of Occurrence
1
0 – 0.2
2
0.2 – 0.4
3
0.4 – 0.6
4
0.6 – 0.8
5
0.8 – 1.0
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., R.P. Neilson, and D.L.
Phillips. 1994. A statistical topographic model for mapping climatological
precipitation over mountainous terrain. Journal of Applied Meteorology
33:140–158.
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.
Phillips, S.J., R.P. Anderson, and R.E. Schapire. 2006. Maximum
entropy modeling of species geographic distributions.
Ecological
Modelling 190: 231-259.
Note: The MC1 model is described in data basin (http://databasin.org/climate-center/features/mc1-dynamic-global-vegetation-model).