You are here
Harvard Forest Symposium Abstract 2006
- Title: Forest-atmosphere exchange processes related to regional carbon budgets, 2005 report
- Primary Author: David Fitzjarrald (SUNY at Albany)
- Additional Authors: Alex Tsoyref (SUNY at Albany)
- Abstract:
1. Forest subcanopy flows and microscale advection of carbon dioxide.
During this period, we completed publication of the second paper on our Harvard Forest studies (Staebler and Fitzjarrald, 2005). Nocturnal flows were driven predominantly by negative buoyancy, with the direction of the resulting drainage flows was determined by the longest forest floor slope. Similar results were found at a flatter site at Borden, Ontario. We are now revisiting the previous data as part of a collaboraive effort to mount a new effort to understand how CO2 may move around in subcanopy flows at Harvard Forest not only at the EMS tower, but also at other flux towers.
2. Climate studies: evapotranspiration and streamflow
We have examined watersheds in the Catskill Mountains of New York to identify the end of the growing season, with emphasis on diurnal fluctuation in streamflow as an indicator of the cessation of ET in the autumn. The smallest watersheds (area < 200 km2) exhibit the diurnal streamflow signal with the greatest frequency and amplitude.
3. Turbulent exchange topics: reanalysis of high-frequency data
We are still completing our effort to reanalyze the multi-year raw (10Hz) turbulence data obtained at the EMS tower. We now have data assembled on the ASRC mass storage deviced, except for a gap during 1994-1996 for which we are still ‘reverse engineering’ old tape drives in an attempt to read recalcitrant tapes. This project is still in progress; out ambition is to complete the initial phase by mid-June 2006. We will produce a ‘turbulence climatology’ that will identify the frequency of occurrence of such phenomena as: waves in the subcanopy that break and release CO2; the effects of high winds flowing over the topography near the EMS site; the properties of subcanopy turbulence needed to model mixing during both stable and convective conditions; and the frequency of isolated mixing events, particularly at night, that evacuate the canopy.
New publications:
Staebler, R. M., and D. R. Fitzjarrald, 2005. Measuring canopy structure and the kinematics of subcanopy flows in two forests. J. Appl. Meteor. 44, 1161-1179.
- Research Category: Forest-Atmosphere Exchange
