[1] Western Washington Univ, Dept Environm Sci, Bellingham, WA 98225 USA
[2] Univ Colorado, Natl Snow & Ice Data Ctr, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA
[3] Texas A&M Univ, Dept Geog, College Stn, TX USA
[4] NOAA, Chem Sci Div, Earth Syst Res Lab, Boulder, CO USA
[5] Univ Colorado, CIRES, Boulder, CO 80309 USA
[6] US Naval Res Lab, Atmospher Properties & Effects Sect, Marine Meteorol Div, Monterey, CA USA