Forest disturbance feedbacks from bedrock to atmosphere using coupled hydro-meteorological simulations over the Rocky Mountain headwaters

Changes to increased soil moisture and Bowen ratios were found to be statistically significant in MPB-infested areas and in nonlocal valleys, while planetary boundary layer (PBL) response was significant only in high elevations of the headwaters watershed. Temperature-humidity covariance was evaluated using mixing diagrams; the results suggest that increased surface Bowen ratios from MPB could affect entrainment of dry air from the troposphere.

The PBL is hotter, drier, and higher under infested forest conditions, which could have implications to atmosphere-vegetation feedbacks and forest drought stress. Finally, land-atmosphere coupling was sensitive to antecedent subsurface moisture. Regions with shallow water tables exhibit greater magnitude response to MPB at the surface and in the PBL, a finding that has repercussions for ecosystem resilience and hydrologic representation in meteorological modeling.