Josh Harvey, Brigham Young University
Life Sciences
Soil CO2 flux represents an important pathway of carbon transfer from ecosystems to the atmosphere. Soil CO2 flux can be altered by global warming-driven changes in seasonal temperature and water availability. Subalpine ecosystems have high levels of carbon in their soils that are stabilized by low temperatures and low microbial activity during long and snowy winter seasons. Subalpine ecosystems can be important sinks for carbon, storing carbon that otherwise would be in the atmosphere contributing to global warming. In our study we show how changes in temperature and water availability during springtime increase the levels of subalpine carbon output. So long as the carbon outputs outweigh carbon inputs, increases in soil flux would amplify global warming. The amplification of global warming would loop back to affect soil fluxes again (by raising temperatures, melting snow earlier, and changing precipitation patterns) thus creating a positive feedback system. Understanding what feedbacks are present in a climate system and their underlying mechanisms will improve our forecasts of changes in atmosphere chemistry and temperature.