Stephen T. Gray
C.A. Woodhouse
Julio L. Betancourt
Daniel B. Fagre
Jeremy S. Littell
Emma Watson
B.H. Luckman
Lisa J. Graumlich
Gregory T. Pederson
2011
<p><span class="search-term-highlight">In</span><span> western </span><span class="search-term-highlight">North</span><span> America, </span><span class="search-term-highlight">snowpack</span><span> has decl</span><span class="search-term-highlight">in</span><span>ed </span><span class="search-term-highlight">in</span><span> </span><span class="search-term-highlight">recent</span><span> decades, and fur</span><span class="search-term-highlight">the</span><span>r losses are projected through </span><span class="search-term-highlight">the</span><span> 21st century. Here, we evaluate </span><span class="search-term-highlight">the</span><span> uniqueness </span><span class="search-term-highlight">of</span><span> </span><span class="search-term-highlight">recent</span><span> </span><span class="search-term-highlight">declines</span><span> us</span><span class="search-term-highlight">in</span><span>g </span><span class="search-term-highlight">snowpack</span><span>reconstructions from 66 tree-r</span><span class="search-term-highlight">in</span><span>g chronologies </span><span class="search-term-highlight">in</span><span> key run</span><span class="search-term-highlight">of</span><span>f-generat</span><span class="search-term-highlight">in</span><span>g areas </span><span class="search-term-highlight">of</span><span> </span><span class="search-term-highlight">the</span><span> Colorado, Columbia, and Missouri River dra</span><span class="search-term-highlight">in</span><span>ages. Over </span><span class="search-term-highlight">the</span><span> past millennium, late 20th century </span><span class="search-term-highlight">snowpack</span><span> reductions are almost unprecedented </span><span class="search-term-highlight">in</span><span> magnitude across </span><span class="search-term-highlight">the</span><span> </span><span class="search-term-highlight">north</span><span>ern Rocky Mounta</span><span class="search-term-highlight">in</span><span>s and </span><span class="search-term-highlight">in</span><span> </span><span class="search-term-highlight">the</span><span>ir </span><span class="search-term-highlight">north</span><span>-south synchrony across</span><span class="search-term-highlight">the</span><span> </span><span class="search-term-highlight">cordillera</span><span>. Both </span><span class="search-term-highlight">the</span><span> </span><span class="search-term-highlight">snowpack</span><span> </span><span class="search-term-highlight">declines</span><span> and </span><span class="search-term-highlight">the</span><span>ir synchrony result from unparalleled spr</span><span class="search-term-highlight">in</span><span>gtime warm</span><span class="search-term-highlight">in</span><span>g that is due to positive re</span><span class="search-term-highlight">in</span><span>forcement </span><span class="search-term-highlight">of</span><span> </span><span class="search-term-highlight">the</span><span> anthropogenic warm</span><span class="search-term-highlight">in</span><span>g by decadal variability. </span><span class="search-term-highlight">The</span><span> </span><span class="search-term-highlight">in</span><span>creas</span><span class="search-term-highlight">in</span><span>g role</span><span class="search-term-highlight">of</span><span> warm</span><span class="search-term-highlight">in</span><span>g on large-scale </span><span class="search-term-highlight">snowpack</span><span> variability and trends foreshadows fundamental impacts on streamflow and water supplies across </span><span class="search-term-highlight">the</span><span> western United States.</span></p>
application/pdf
10.1126/science.1201570
en
AAAS
The unusual nature of recent snowpack declines in the North American cordillera
article