Purdue Climate Change Research Center

Quantifying Climate Feedbacks from Abrupt Changes in High-Latitude Trace-Gas Emissions

Funded by the Department of Energy

The overall goal of this project is to quantify the potential for threshold changes in natural emission rates of trace gases, particularly methane and carbon dioxide, from pan-Arctic terrestrial systems under the spectrum of anthropogenically forced climate warming, and the extent to which these emissions provide a strong feedback mechanism to global climate warming. This goal is motivated by the premise that polar amplification of global climate warming will induce widespread thaw and degradation of permafrost, and would thus cause substantial changes in the extent of wetlands and lakes, especially thermokarst (thaw) lakes, over the Arctic.

Through a suite of global model experiments that encapsulate the fundamental processes governing methane emissions – as well as their coupling to the global climate system -the team will test the following hypothesis: A climate warming threshold exists beyond which permafrost degradation becomes widespread and instigates strong and/or sharp increases in methane emissions (via thermokarst lakes and wetland expansion). These emissions would outweigh any increased uptake of carbon (e.g., from peatlands) and would result in a strong, positive feedback to global climate warming.


  • Qianlai Zhuang, Departments of Earth & Atmospheric Sciences and Agronomy
  • Adam Schlosser, Massachusetts Institute of Technology
  • Jerry Melillo, Marine Biological Laboratory
  • Katey Walter, University of Alaska, Fairbanks

Contact Information

Purdue University
203 S. Martin Jischke Drive
MANN 105
West Lafayette, IN 47907