NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Collections About News Help Login
Back to Results
The evaluation of evaporation by infrared thermography: A critical analysis of the measurements on the Crau test siteEvapotranspiration was calculated for both the dry and irrigated zone by four methods which were compared with the energy balance method serving as a reference. Two methods did not involve the surface temperature. They are ETR(n) = R(n), liable to be valid under wet conditions and ET(eq) = (delta/delta + gamma) R(n) i.e, the first term of Penman's equation, adapted to moderately dry conditions. The methods using surface temperature were the combined energy balance aerodynamic approach and a simplified approach proposed by Jackson et al. Tests show the surface temperature methods give relatively satisfactory results both in the dry and wet zone, with a precision of 10% to 15% compared with the reference method. As was to be expected, ET(eq) gave satisfactory results only in the dry zone and ET(Rn) in the irrigated zone. Thermography increased the precision in the estimate of ET relative to the most suitable classical method by 5% to 8% and is equally suitable for both dry and wet conditions. The Jackson method does not require extensive ground measurements and the evaluation of the surface roughness.
Document ID
19810004010
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Seguin, B. (Institut National de la Recherche Agronomique Avignon, France)
Petit, V. (Centre d'Informatique Geologique Fontainbleau, France)
Devillard, R. (Institut National de la Recherche Agronomique Avignon, France)
Reich, P. (Institut National de la Recherche Agronomique Avignon, France)
Thouy, G. (Institut National de la Recherche Agronomique Avignon, France)
Date Acquired
September 4, 2013
Publication Date
June 1, 1980
Publication Information
Publisher: Joint Research Centre of the European Communities
Subject Category
Earth Resources And Remote Sensing
Report/Patent Number
E81-10039
NASA-CR-163546
NEWSLETTER-16
Accession Number
81N12521
Funding Number(s)
PROJECT: PROJ. TELLUS
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

Related Records

There are no records associated with this record.
No Preview Available