An eddy covariance system measures CO2 exchange between melting Alaskan permafrost and the atmosphere. At a site in Healy, Alaska, near Denali National Park, a long-term research project studies the release of carbon dioxide into the atmosphere by permafrost that is thawing due to global climate change. The project, led by Dr. Ted Schuur of University of Florida, has found that in the short term CO2 released from decomposing, melting permafrost leads to increased growth of local tundra vegetation. But in the longer term the thawing leads to increased atmospheric loading of CO2. One factor studied is the percentage composition of old isotopes of carbon that are found in CO2 that has been trapped in permafrost for hundreds or thousands of years..The apparatus here is an eddy covariance tower which contains an anemometer and an infrared gas analyzer to measure local carbon dioxide flux.