%0 Journal Article
%@nexthigherunit 8JMKD3MGPCW/3EUPEJL
%@holdercode {isadg {BR SPINPE} ibi 8JMKD3MGPCW/3DT298S}
%X During summer and autumn 2007, a 11 GHz microwave radiometer was deployed in an experimental tree plantation in Sardinilla, Panama. The opacity of the tree canopy was derived from incoming brightness temperatures received on the ground. A collocated eddy-covariance flux tower measured water vapor fluxes and meteorological variables above the canopy. In addition, xylem sapflow of trees was measured within the flux tower footprint. We observed considerable diurnal differences between measured canopy opacities and modeled theoretical opacities that were closely linked to xylem sapflow. It is speculated that dielectric changes in the leaves induced by the sapflow are causing the observed diurnal changes. In addition, canopy intercepted rain and dew formation also modulated the diurnal opacity cycle. With an enhanced canopy opacity model accounting for water deposited on the leaves, we quantified the influence of canopy stored water (i.e. intercepted water and dew) on the opacity. A time series of dew formation and rain interception was directly monitored during a period of two weeks. We found that during light rainfall up to 60% of the rain amount is intercepted by the canopy whereas during periods of intense rainfall only 4% were intercepted. On average, 0.17 mm of dew was formed during the night. Dew evaporation contributed 5% to the total water vapor flux measured above the canopy.
%@mirrorrepository sid.inpe.br/mtc-m19@80/2009/08.21.17.02.53
%8 Aug.
%N 8
%T Relating the X-band opacity of a tropical tree canopy to sapflow, rain interception and dew formation
%@secondarytype PRE PI
%K X-band, Tropics, Rain interception, Dew, Sapflow, Radiometry, Microwave techniques, Eddy covariance, SAP FLOW, DIELECTRIC-CONSTANT, FLUX MEASUREMENTS, FOREST CANOPY, HEAT-FLUX, WATER, MODEL, SOIL, TRANSPIRATION, EVAPORATION.
%@archivingpolicy denypublisher allowfinaldraft24
%@usergroup administrator
%@usergroup marciana
%@group CPT-CPT-INPE-MCT-BR
%3 schneebeli.pdf
%@secondarykey INPE--PRE/
%@issn 0034-4257
%2 sid.inpe.br/mtc-m19/2011/07.25.13.40.28
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Ecole Polytech Fed Lausanne, Environm Remote Sensing Lab, CH-1015 Lausanne, Switzerland, Univ Bern, Inst Appl Phys, CH-3012 Bern, Switzerland
%@affiliation ETH, Inst Plant Anim & Agroecosyst Sci, Zurich, Switzerland
%@affiliation Max Planck Institute Biogeochem, Dept Biogeochem Proc, Jena, Germany
%@affiliation ETH, Inst Plant Anim & Agroecosyst Sci, Zurich, Switzerland
%@project German Research Foundation Ho-2119/3-1
%B Remote Sensing of Environment
%@versiontype publisher
%P 2116-2125
%4 sid.inpe.br/mtc-m19/2011/07.25.13.40
%@documentstage not transferred
%D 2011
%V 115
%@doi 10.1016/j.rse.2011.04.016
%A Schneebeli, Marc,
%A Wolf, Sebastian,
%A Kunert, Norbert,
%A Eugster, Werner,
%A Maetzler, Christian,
%@dissemination WEBSCI; PORTALCAPES; MGA; COMPENDEX.
%@area SRE