News & Events

PhD defense - Sean P. Burns

Friday, May 04, 2018, 9:00AM - 11:00AM

Speaker

Sean P. Burns

Location:

SEEC room S228 (Sievers Conference Room)

4001 Discovery Drive, Boulder

Title

Ecosystem fluxes in a subalpine forest below Niwot Ridge, Colorado: Measurements and modeling

Abstract

Ecosystem-scale exchange of heat, water vapor, and carbon dioxide between the forest and atmosphere has been measured using the eddy-covariance technique at the Niwot Ridge Subalpine Forest AmeriFlux site (US-NR1) since 1 November 1998.  This site is within 1 km of the long term LTER C-1 site and Veblen forest plots in the subalpine forest below Niwot Ridge. After a brief introduction to US-NR1 measurements (and the history of the forest), the influence of warm-season precipitation on the ecosystem fluxes, atmospheric turbulence, and meteorological measurements is described.  For the modeling portion of the talk, the US-NR1 tower meteorological data are used to drive the Community Land Model (CLM, version 4.5) and the CLM-derived ecosystem fluxes are compared with the measured fluxes. The model-observation comparison focuses on water vapor fluxes, and suggests potential areas for model improvement, as well as additional measurements that would help us better understand evapotranspiration within this subalpine forest.