A high-speed methane analyzer to quantify atmospheric concentrations and net ecosystem exchange of methane in the Canadian high Arctic

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Concentrations of the powerful greenhouse gas (GHG) methane (CH4) have been steadily increasing in the atmosphere over the past 2.5 centuries due to human activities. CH4 has a global warming potential 25 times that of carbon dioxide (CO2), and is considered the second most important anthropogenic GHG after CO2. Ironically, human-induced climate change is warming Canadian polar ecosystems at unprecedented rates, further accelerating emissions of CH4 to the atmosphere from thermokarst lakes, peatlands, lake sediments, thawing permafrost, and CH4 hydrates in Arctic marine sediments, to name a few. However, there are also numerous "sinks" of CH4 in polar regions, such as the oxidation of CH4 in the oxic regions of peatlands, in oxygenated water columns of lakes and oceans, and in dry desert tundra soils that make up a significant portion of the Canadian high Arctic landscape. These sinks are equally important to understand because they both prevent CH4 from ever entering the atmosphere, or actually consume atmospheric CH4. As a result, it has become imperative that we accurately and continuously quantify these sinks and sources of CH4 in the high Arctic because it has important implications for Canada's GHG budgeting. I am requesting funds to purchase a LI-COR 7700 Open Path CH4 Analyzer to: 1) quantify the net ecosystem exchange of CH4 with high-Arctic landscapes, and 2) monitor concentrations of CH4 in the high-Arctic atmosphere to rapidly detect aberrant releases from sources such as CH4 hydrates. This analyzer will be deployed in Quttinirpaaq National Park (northern Ellesmere Island, Nunavut), the most northerly site ever studied for these measurements. The LI-COR 7700 will be used for postdoctoral, graduate and undergraduate student training in my laboratory, as well as contribute to Northern outreach and training. Furthermore, the data will be archived in open-access databases, and collaboratively shared with colleagues for regional modeling exercises. Unfortunately, without the LI-COR 7700, we will be forced to end our novel research program on CH4 sinks and sources in the high Arctic because current techniques to make these measurements are no longer scientifically worthwhile.