Research Projects

Ongoing Projects 

Magnitude and timing of permafrost C emission from the Arctic

  1. We are quantifying the sources of CH4 emitted from arctic lakes on the North Slope of Alaska. This is a collaboration with the CALON group (Prof. A. Townsend-Small, University of Cincinnati, OH). www.arcticlakes.org
  2. We are investigating the effect of shrub expansion on permafrost thaw and carbon cycling in arctic tundra.
  3. During the winter of 2012-2013, we quantified the magnitude and sources of wintertime CO2 emissions from high arctic tundra as a function of snow depth in Adventdalen, Svalbard.  This is a collaboration with Profs J. Welker (UA Anchorage, 2012-2013 Fulbright Arctic Chair) & E. Cooper (University of Tromso, Norway).

Sources and fate of carbonaceous aerosols
In several projects, we are using isotopes to investigate the sources of carbonaceous aerosols. Study sites include Salt Lake City, UT, Interior Alaska (USA), Seoul (South Korea), Singapore, and Alert (Canada).

Nonstructural carbohydrates in trees
We are investigating the age and usage of nonstructural carbon pools in long-lived desert plants in Baja California, Mexico.  This is a collaboration with Prof. R. Vargas (CICESE & University of Delaware).

Selected, completed Projects
How will climate change affect arctic tundra systems?
2010-2013. We quantified the effects of warming, summer rainfall and wintertime snow depth on the seasonality, magnitude and sources of summertime emissions of CO2 and CH4 from high arctic tundra at two long-term climate change experiments near Thule, Greenland. This was a collaboration with Profs J. Welker (UA Anchorage), J. Schimel (UC Santa Barbara) & U. Seibt (UC Los Angeles).