Water vapor fluxes from snow covered landscapes: the importance of biotic and abiotic-mediated processes

2015 Spring Cyberseminar Series

Adrian Harpold / University of Nevada-Reno

Talk Description:

Water Vapor Fluxes from Snow Covered Landscapes: The Importance of Biotic and Abiotic-Mediated Processes Snow dominated systems are critical for providing water resources and maintaining ecological health across much of the Western U.S. and worldwide.  These landscapes are sensitive to altered snowpack dynamics from regional warming and vegetation disturbance.  Consequently, understanding how variable and changing snowpacks will alter partitioning to evaporation, sublimation, transpiration, and runoff is critical to current and future water availability.  In this presentation, I will highlight several ecohydrological paradoxes and tradeoffs that require better observations and process-based understanding of evapotranspiration in snow-dominated systems.  For example, evidence suggests that snowmelt is both an efficient irrigator of forest vegetation and effective in streamflow generation.  The second example presented is the tradeoff between increasing interception of snowfall and decreasing below-canopy snowpack sublimation with greater vegetation canopy cover.  The final example is the tradeoff between abiotic (sublimation and evaporation) and biotic (transpiration) vapor losses on the water budget of forest systems.  Disturbed and undisturbed forests in the Rocky Mountains are used to illustrate the challenges associated with observing and understanding these tradeoffs and paradoxes.  Although modeling and observational tools are advancing rapidly, our prediction of water vapor fluxes from snow-dominated systems must improve to address potential threats from environmental change.

CUAHSI's Spring 2015 Cyberseminar Series on  Evapotranspiration - Frontiers in measurement, modeling and management from the leaf to the landscape!

Hosted by Steven Brantley, Joseph W. Jones Ecological Research Center