This dataset is used in the
Utah & Colorado Plateau Environmental Evaluation Mapping and Plotting System (EEMAPS), a
web mapping application designed for exploring climate projections and
fuzzy logic (EEMS) model results for the state of Utah & the
Colorado Plateau.
Criteria set forth by the Utah Division of
Natural Resources (UT-DWR) and Utah State Office of the Bureau of Land
Management (UT-BLM) specified that the time periods used in the analysis
be consistent with those used in the Colorado Plateau Rapid Ecological
Assessment Report (Bryce et al., 2012), the spatial resolution for the
study area be downscaled from 4 km x 4 km pixel resolution to 1 km x 1
km, that data used for future climate projections be obtained from phase
5 of the Coupled Model Intercomparison Project (CMIP5; Taylor et al.,
2012), and that the study area be expanded to include the entire State
of Utah as well as the Colorado Plateau (Figure 1).
The time
series climate data used to represent the historical period (1968-1999)
were obtained from the LT71m PRISM 30 arc-second spatial climate dataset
for the Conterminous United States (Daly et al., 2008). We evaluated
ten of the 34 CMIP5 General Circulation Models (GCMs) that have been
shown to reproduce several observed climate metrics such as the Pacific
Decadal Oscillation (PDO) and El Niño Southern Oscillation (ENSO) over
the study area (Wang et al., 2011; Wang et al., 2014). Four models
(Table 1) were selected that captured the full range of projected change
for both annual average temperature and annual precipitation (Figure 2)
under the representative concentration pathway 8.5 (RCP8.5; Meinshausen
et al., 2011; van Vuuren et al., 2011). We then obtained downscaled
time series climate projections for the selected GCMs from the NASA
Earth Exchange (NEX) U.S. Downscaled Climate Projections (NEX US-DCP30)
dataset (Thrasher et al., 2013) for the entire spatial extent of the
study area and for the period 2015-2060 time. The multi-model ensemble
mean of the four downscaled climate models was calculated for each of
the climate variables discussed below.
Download the complete
Methods document (PDF).
Post-Processing:
For analytical purposes, all climate datasets were converted from
NetCDF files to geodatabase rasters and subsequently shifted by
0.004166666667 decimal degrees in both latitude and longitude to correct
for the shift in the NEX data. Each dataset was then projected to
USA_Contiguous_Albers_Equal_Area_Conic_USGS_version_NAD83 at a 1km
resolution using a cubic convolution resampling method, and set to snap
to the 1km grid used for the UTAH-DWR-COP-BLM climate/intactness
project.