Length of the Snow Season Map: All Scenarios

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<hr /><p><span style='font-weight:bold;'>A pre-configured, multi-layer web map for viewing all Length of Snow Season scenarios.</span> <span style='font-style:italic;'>(To
launch the map from the Climate Change Open Data site, select &quot;View
Metadata&quot; under the &quot;About&quot; heading, then look for the button labeled
&quot;Open in Map Viewer&quot; to the upper right.)</span></p><p>The map layers depict historical, and projected changes in, Length of the Snow Season,
which is defined as the number of days between the dates of 10%
accumulation and of 90% melt, relative to annual maximum snow water
equivalent (SWE). Results are shown only for
watersheds with an average historical April 1st SWE of at least 0.4
inch. April 1st is the approximate current timing of peak annual
snowpack in the mountains of the Northwest. Geographic units: HUC10. <br /></p><p>Map layer data include historical
conditions (1970-1999) and the projected changes for ten global models. Two time periods are considered: the 2040s
(2030-2059) and the 2080s (2070-2099), based on a moderate greenhouse
gas scenario (A1B).<span style='font-style:italic;'> <br /></span></p><p>Data
classes and symbology by Robert Norheim, Climate Impacts Group, based
on the CMIP3 projections used in the IPCC 2007 report. </p><p>Data source: Hamlet et al. 2013.</p>