Connectivity for climate change adaptation in California

This spatial data identifies connectivity potential between natural lands
in the present climate and natural lands with future analogous climate
following topo-climatically diverse routes. Present-day land use,
topographic diversity, and projections of shifting climate regimes were
combined into a single connectivity modeling approach to identify pathways
for mid-century shifts in species ranges. Climate linkages, or areas
important for climate change-driven movement, were identified as the areas
where the Omniscape model indicated more current flow than would be
expected in the absence of climate considerations. The model was run for
two different projections of future climate (CNRM_CM5 and HADGEM2-ES).
Climate linkages from both models were overlaid with a strategic
present-day connectivity framework to improve interpretation and to
facilitate a more direct connection with conservation action. This
connectivity model is a structural, coarse filter approach that explicitly
incorporates human modification as a factor that will limit movement for
species moving in response to climate change as that has been shown to
pose an additional threat to climate-driven movement. This approach also
addresses the multiple scales at which suitable climates may drive species
distributions by modeling connectivity between the broad shifts in
coarsely-defined climate “space” along routes with finer-scale topoclimate
diversity. Finally, it accounts for the longer timeframes and incremental
movements necessary for multi-generational range shifts by incorporating
the likelihood of climate-driven movement across microclimate
stepping-stones. This approach includes the following assumptions: Species
will move towards locations where the future climate is analogous to the
present-day climate they are experiencing. Species range shifts often
require multi-generational movements over a longer temporal period, and
therefore, routes that provide microclimate stepping stones with habitat
suitable for all phases of a species’ life-cycle are needed. Topoclimate
diversity confers microclimate diversity and therefore is more likely to
provide suitable climate options, facilitating dispersal for species
tracking suitable climate.