Carl Schmitt: Dust and black carbon on glaciers Cordillera Blanca, Peru PPT

Carl G. Schmitt National Center for Atmospheric Research

Aaron Celestian, John All, Melinda Rucks, Justin Cave Western Kentucky University

William P. Arnott

University of Nevada, Reno

Rebecca Cole

Institute of Arctic and Alpine Research

Ellen Lapham

 

American Climber Science Program Dust and Black Carbon sampling     

Motivations Sampling Methods and Analysis of samples Results Future research Conclusions

All volunteer citizen science program.  Scientist and non-scientist (climbers) participate in research expeditions.  Climbers help scientists with data collection in the valleys and on the mountains.  Sampling protocols are designed to be simple so that they can be completed in the field under challenging conditions.  Scientific value: A modest sacrifice in data quality is exchanged for a large quantity of data. 

 

Tropical glacier area loss: 2% per year in 2000s Changes leading to increased glacier melt rates:   



Temperatures increasing 0.1C/decade.

Weather pattern shifts.

Increased pollution and dust leads to more light absorbing particles on glacier surfaces.

Dust and Black Carbon on glaciers can increase melt rates significantly altering “peak water” estimates.

Collect bags of snow at pre-determined locations, typically: 1. Sample every 2-500 meters in altitude depending on the mountain.

2. Two samples from each location, a “surface” sample and a “subsurface” sample.

Snow is melted then immediately filtered through 0.7 micron pore size quartz fiber filters. For all samples, 600 ml of water is filtered.

Filters are stored in small plastic “coin holders� after filtering.

100 snow samples were collected and filtered during the 2012 expedition.

Heat capacity measurements

Relative absorptive capacity

70 60 50

2011

40

2012

30 20 10 0 santa cruz

Llanganuco

Ishinca

Vallu

Quilquay

During 2011 expedition a storm blew through as teams went out to sample.

San Juan: 69 Vallunaraju: 64 Yannapaccha: 18 Huascaran: 19 Glaciers near Huaraz had significantly heavier loads of absorptive materials.

Sampling through time: 14 layers sampled from top to bottom of a crevasse on Vallunaraju sfc layer 1 layer 2 layer 4 layer 5 layer 6 layer 7 layer 8 layer 10 layer 11 layer 12 layer 13 layer 14 layer 15 layer 16

Dominant mineralogy: Quartz, sodium rich plagioclase feldspar, and biotite/muscovite.

Also abundant: Mercury sulfides (possibly from mining or smelting sources) A recent Nature publication has shown that feldspar is a very active ice nuclei. We have found feldspar on most of our filters including some of the cleanest filters.







Mineralogy work is only going down to 1 micron, so most combustion black carbon (200 nm) is being missed. We will be taking snow samples back to the US for analysis with a Soot Photometer 2 (SP2) instrument.

Co-located SP2 and filter sampling will enable us to spectroscopically determine black carbon and dust separation for previous filters.

If we climb into clouds this year we will be sampling cloud particles in order to determine the nuclei (formvar capture and electron microscope analysis).







The ACSP is in its third year of sampling pollutants on glaciers in the Cordillera Blanca.

The first two years of data indicate that mountains near Huaraz have higher loads of light absorbing materials than the north end of the range.

Population centers are sources of pollution. If glaciers near these population centers are melting more rapidly due to pollution, this effect could be very important for long term water planning.

  





Universidad Nacional Santiago Antúnez de Mayolo Huascaran National Park ACSP 2011: Frank Nederhand, Ellen Lapham, John All, Rebecca Cole, Alex Stella, Bill Straka, Clinton Lewis, Kevin Grove, Brett Overcash, Carolyn Stwertka, David Truncellito, James Pinter-Lucke, Mark Milner, Pat Gioannini, Rauel Gavilan, Trevor Alcott ACSP 2012: John All, Ellen Lapham, Rebecca Cole, Kate Von Krusenstiern, Ruth Sofield, Rachelle Combs, W. Pat Arnott, Bernhard Bach, Ed Laughton, James Holmes, Collin Steiner, James Benningfield Contact information: schmittc@ucar.edu