So fires influence climate change several important ways. One is they contribute to the buildup of greenhouse gases including methane, carbon dioxide and nitrous oxide. Another way that they contribute to climate change is they change regional climate. For example the smoke that's emitted by fires can change patterns of temperatures and also rainfall near the areas that are burning. In the Arctic and in high latitude ecosystems the particles that are emitted by fires can be transported by winds where there's a lot of ice. When these particles deposit on the surface they cause darkening of the snow and that contributes to their melting. Another important way is they actually change and modify the vegetation within a region within the burn perimeter. And this can lead locally to changes in surface reflectance that may either warm or cool climate. And the vegetation that comes back may evaporate water at a different rate, and that also can contribute to the change in the cloudiness and to the regional climate. So there are several different pathways by which fires influence climate.