Harvard Forest Research

Canopy Phenology, Remote Sensing, and Microclimate

Principal Investigator: Mark Friedl
Boston University: Jan 01 2008 - Dec 31 2010:

Abstract:
Our research at the Harvard Forest walk-up tower site examines how seasonality of canopy leaf area, or canopy phenology, influences, and is influenced by, local climate. As part of this activity we are examining methods for (and limits to) remote sensing of canopy phenology. To address this research topic, we have initiated measurements to quantify how radiation fluxes through a deciduous forest canopy are modified by seasonal canopy leaf dynamics. We continuously measure above- and below-canopy radiation fluxes at a variety of spectral bands (shortwave, photosynthetic, and thermal infrared) and with digital photography. These measurements provide a surrogate measure of canopy leaf area dynamics, and directly represent the radiation component of the surface energy balance. To build on these measurements, future plans are to include measurements of latent and sensible heat transfer and water balance (using soil moisture and temperature sensors, and tree sap flow sensors). These measurements will complement ongoing microclimate and eddy covariance measurements of water and carbon exchange at the EMS flux tower. This research extends previous efforts examining sap-flux dynamics by one of the co-investigators (Phillips) and builds on previous and ongoing research at Harvard Forest by researchers including David Fitzjarrald, Julian Hadley, Bill Munger, Andrew Richardson, Steve Wofsy, and John O’Keefe.: