Turbulence, heat and trace gas fluxes above a South-East Asian rainforest

Two major intensive field campaigns were conducted in Malaysian Borneo during the first half of 2008 by a NERC-funded consortium of eight UK institutions, aiming at investigating Oxidant and Particle Photochemical Processes (OP3). As part of this study, flux measurements were made from the Global Atmospheric Watch (GAW) tower located in the Danum Valley conservation area; this tower stands 100 m tall on a small hill. The forest surrounding the GAW tower can be described as selectively logged diptocarp forest.Here we present the micrometeorological characteristics of the GAW site and examine its diurnal turbulence as observed between April and July 2008. We also present fluxes of trace gases (CO2, O3) and heat atop the GAW tower by eddy-covariance and modified Bowen ratio technique and investigate their controls.