SVERIGES LANTBRUKSUNIVERSITET - Epsilon Open Archive - SLU

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irrigation management and to carry further research on the water
movement in the soil-plant-atmosphere system.
5. Summary
Recently, reliable and relatively low cost infrared temperature
sensors have become available, allowing the practical determination of
sensible and latent heat fluxes over homogeneous terrains. The
appropriate micrometeorological theory uses the energy balance and
aerodynamic equations to calculate actual water loss from the surface.
Automated weather stations can be equipped to monitor actual
evaporation in stead of using lysimeters or other sophisticated
research methods that require great care and maintenance.
Routine estimates of site-specific actual evapotranspiration for
different crops is essential for the study of the water balance of
soil and plants. Obtained from many locations at representative sites
this information, together with the standard meteorological data could
also be used in real time by the information systems that serve the
farmer.
6. References
Brutsaert, W. 1982: Evaporation in to the Atmosphere, Theory, History
and Applications. Reidel, Dordrecht, Holland, 299 pp.
Kustas, W.P., B.J. Choudhury, M.S. Moran, R.J. Reginato, R.D.
Jackson, L.W. Gay, H.L. Weaver, 1989: Determination of sensible
heat flux over spar se canopy using thermal infrared data.
Agric.For. Met., 44, 197-216.
Launiainen, 1983: Parametrization of the water vapour flux over a
water surface by the bulk aerodynamic method. Annales
Geophysicae, 6, 481-492.
Tanner, C.B., 1960:. Energy balance approach to evapotranspiration
from crops. Soil Sci.Soc. Am.Proc., 24, 1-9.