ESTIMATING EVAPORATION FROM WATER SURFACES

ESTIMATING EVAPORATION FROM WATER SURFACES (With emphasis on shallow WATER bodies) 1ET Workshop12 Mar 2010 INTRODUCTIONINTRODUCTION EvaporationisrarelymeasureddirectlyEvapo ration is rarely measured directly ESTIMATING methods include:ffi i tdti pan coefficient xmeasured pan EVAPORATION WATER balance energy balance mass transfer combination techniques Emphasis will be practical methods2ET Workshop12 Mar 2010 BACKGROUNDBACKGROUND Evaporationtheories tothe8thcenturyEvaporation theories to the 8century Dalton (1802), E = f( ) (eo ea)( 926)hihif Bowen (1926), the Bowen ratio, the ratio of sensible heat to latent heat gradients ( t/ e) Applications were made to lake EVAPORATION by Cummings and Richardson 1927; McEwen 19303ET Workshop12 Mar 2010 ENERGYCONSIDERATIONSENERGY CONSIDERATIONS EvaporationrequiresalotofenergyEvaporati on requires a lot of energy Incoming solar radiation is the main sourceldllldi i In contrast to land, not all net solar radiation is absorbed on the surface In pure WATER , about 70% is adsorbed in the top 5 m (16 ft) Solar radiation adsorbed below the surface is stored energy gy4ET Workshop12 Mar 2010 ENERGY(continued)ENERGY (continued) Estimatingenergystorageinwater(Qt)canEst imating energy storage in WATER (Qt) can be more dif

• Location San Luis Valley – Elevation 2297 m (7536 ft) above sea level – AverageAverage depth, about 151.5 m (5 ft) • Estimated energy storage • Estimated evaporation – May‐October – ET ref x K w also agrees with PM in November • Results …

Loading..

Tags:

  Form, Surfaces, Water, Estimating, Luis, Evaporation, San luis, Estimating evaporation from water surfaces

Information

Related search queries