Dynamic coupling of volcanic CO 2 flow and wind at the Horseshoe Lake tree kill, Mammoth Mountain, California

We investigate spatio‐temporal relationships between soil CO 2 flux (F CO2 ), meteorological variables, and topography over a ten‐day period (09/12/2006 to 09/21/2006) at the Horseshoe Lake tree kill, Mammoth Mountain, CA. Total CO 2 discharge varied from 16 to 52 t d −1 , suggesting a decline in CO 2 emissions over decadal timescales. We observed systematic changes in F CO2 in space and time in association with a weather front with relatively high wind speeds from the west and low atmospheric pressures. The largest F CO2 changes were observed in relatively high elevation areas. The variations in F CO2 may be due to dynamic coupling of wind‐driven airflow through the subsurface and flow of source CO 2 at depth. Our results highlight the influence of weather fronts on volcanic gas flow in the near‐surface environment and how this influence can vary spatially within a study area.