Measurements of Light Absorbing Particles on Tropical South American Glaciers

Tuesday, 16 December 2014: 5:15 PM
Carl G Schmitt1, John All2, Joshua Peter Schwarz3, William P Arnott4, Julio Warthon5, Marcos Andrade6, Aaron J Celestian2, Dirk Hoffmann7, Rebecca J Cole8, Ellen Lapham9, Ulyana N Horodyskyj10, Karl D Froyd11 and Jin Liao12, (1)National Center for Atmospheric Research, NESL-MMM, Boulder, CO, United States, (2)Western Kentucky University, Bowling Green, KY, United States, (3)NOAA ESRL, Boulder, CO, United States, (4)University of Nevada Reno, Reno, NV, United States, (5)University San Antonio Abad, Physics, Cusco, Peru, (6)Higher University of San Andrés, La Paz, Bolivia, (7)Bolivian Mountain Institute, La Paz, Bolivia, (8)University of Hawaii at Manoa, Honolulu, HI, United States, (9)American Climber Science Program, Eldora, CO, United States, (10)University of Colorado at Boulder, Boulder, CO, United States, (11)NOAA/University of Colorado, Boulder, CO, United States, (12)NOAA Boulder, Boulder, CO, United States
Glaciers in the tropical Andes have been losing mass rapidly in recent decades. In addition to the documented increase in temperature, increases in light absorbing particulates deposited on glaciers could be contributing to the observed glacier loss. Here we present results of measurements of light absorbing particles from glaciers in Peru and Bolivia. Samples have been collected by American Climber Science Program volunteers and scientists at altitudes up to 6770 meters. Collected snow samples were melted and filtered in the field. A new inexpensive technique, the Light Absorption Heating Method (LAHM) has been developed for analysis of light absorbing particles collected on filters. Results from LAHM analysis are calibrated using filters with known amounts of fullerene soot, a common industrial surrogate for black carbon (BC). For snow samples collected at the same field location LAHM analysis and measurements from the Single Particle Soot Photometer (SP2) instrument are well correlated (r2 = 0.92). Co-located SP2 and LAHM filter analysis suggest that BC could be the dominant absorbing component of the light absorbing particles in some areas.