Details

Autor(en) / Beteiligte

• Sánchez, J.M.
• Caselles, V.
• Niclòs, R.
• Coll, C.
• Kustas, W.P.

Titel

Estimating energy balance fluxes above a boreal forest from radiometric temperature observations

Ist Teil von

• Agricultural and forest meteorology, 2009-06, Vol.149 (6), p.1037-1049

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

2009

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The great areal extent of boreal forests confers these ecosystems potential to impact on the global surface-atmosphere energy exchange. A modelling approach, based on a simplified two-source energy balance model, was proposed to estimate energy balance fluxes above boreal forests using thermal infrared measurements. Half-hourly data from the Solar-Induced Fluorescence Experiment, carried out in a Finnish boreal forest, was used to evaluate the performance of the model. Energy balance closure, determined by linear regression, found all fluxes to underestimate available energy by 9% ( r 2 = 0.94). Significance in the energy balance of the heat storage in the air and in the soil terms was also analyzed. Canopy temperatures, measured by a CIMEL Electronique CE 312 radiometer, together with ancillary meteorological variables and vegetation characteristics, were used to run the model. Comparison with ground measurements showed errors lower than ±15 W m −2 for the retrieval of net radiation, soil heat flux and storage heat flux, and about ±50 W m −2 for the sensible and latent heat fluxes. A sensitivity analysis of the approach to typical operational uncertainties in the required inputs was conducted showing the necessity of accurate measurements of the target radiometric surface temperature.