Advanced Search
Syntax
Search...
Volcani treasures
About
Terms of use
Manage
Community:
אסיף מאגר המחקר החקלאי
Powered by ClearMash Solutions Ltd -
Evaporation from a small water reservoir: Direct measurements and estimates
Year:
2008
Source of publication :
Journal of Hydrology
Authors :
Assouline, Shmuel
;
.
Cohen, Shabtai
;
.
Grava, Avraham
;
.
Tanny, Josef
;
.
Volume :
351
Co-Authors:
Tanny, J., Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, P.O. Box 6, Bet Dagan, 50250, Israel
Cohen, S., Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, P.O. Box 6, Bet Dagan, 50250, Israel
Assouline, S., Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, P.O. Box 6, Bet Dagan, 50250, Israel
Lange, F., Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, P.O. Box 6, Bet Dagan, 50250, Israel
Grava, A., Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, P.O. Box 6, Bet Dagan, 50250, Israel
Berger, D., Mekorot - The National Water Company, P.O. Box 610, Nazareth Illit, 17105, Israel
Teltch, B., Mekorot - The National Water Company, P.O. Box 610, Nazareth Illit, 17105, Israel
Parlange, M.B., School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), ENAC/ISTE, Lausanne, Switzerland
Facilitators :
From page:
218
To page:
229
(
Total pages:
12
)
Abstract:
Knowing the rate of evaporation from surface water resources such as channels and reservoirs is essential for precise management of the water balance. However, evaporation is difficult to measure experimentally over water surfaces and several techniques and models have been suggested and used in the past for its determination. In this research, evaporation from a small water reservoir in northern Israel was measured and estimated using several experimental techniques and models during the rainless summer. Evaporation was measured with an eddy covariance (EC) system consisting of a three-dimensional sonic anemometer and a Krypton hygrometer. Measurements of net radiation, air temperature and humidity, and water temperature enabled estimation of other energy balance components. Several models and energy balance closure were evaluated. In addition, evaporation from a class-A pan was measured at the site. EC evaporation measurements for 21 days averaged 5.48 mm day-1. Best model predictions were obtained with two combined flux-gradient and energy balance models (Penman-Monteith-Unsworth and Penman-Brutsaert), which with the water heat flux term, gave similar daily average evaporation rates, that were up to 3% smaller than the corresponding EC values. The ratio between daily pan and EC evaporation varied from 0.96 to 1.94. The bulk mass transfer coefficient was estimated using a model based on measurements of water surface temperature, evaporation rate and absolute humidity at 0.9 and 2.9 m above the water surface, and using two theoretical approaches. The bulk transfer coefficient was found to be strongly dependent on wind speed. For wind speeds below 5 m s-1 the estimated coefficient for unstable conditions was much larger than the one predicted for neutral conditions. © 2007 Elsevier B.V. All rights reserved.
Note:
Related Files :
Anemometers
humidity
measurement method
Net radiation
reservoir
Reservoirs (water)
wind velocity
Show More
Related Content
More details
DOI :
10.1016/j.jhydrol.2007.12.012
Article number:
0
Affiliations:
Database:
Scopus
Publication Type:
article
;
.
Language:
English
Editors' remarks:
ID:
20239
Last updated date:
02/03/2022 17:27
Creation date:
16/04/2018 23:35
Scientific Publication
Evaporation from a small water reservoir: Direct measurements and estimates
351
Tanny, J., Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, P.O. Box 6, Bet Dagan, 50250, Israel
Cohen, S., Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, P.O. Box 6, Bet Dagan, 50250, Israel
Assouline, S., Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, P.O. Box 6, Bet Dagan, 50250, Israel
Lange, F., Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, P.O. Box 6, Bet Dagan, 50250, Israel
Grava, A., Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, P.O. Box 6, Bet Dagan, 50250, Israel
Berger, D., Mekorot - The National Water Company, P.O. Box 610, Nazareth Illit, 17105, Israel
Teltch, B., Mekorot - The National Water Company, P.O. Box 610, Nazareth Illit, 17105, Israel
Parlange, M.B., School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), ENAC/ISTE, Lausanne, Switzerland
Evaporation from a small water reservoir: Direct measurements and estimates
Knowing the rate of evaporation from surface water resources such as channels and reservoirs is essential for precise management of the water balance. However, evaporation is difficult to measure experimentally over water surfaces and several techniques and models have been suggested and used in the past for its determination. In this research, evaporation from a small water reservoir in northern Israel was measured and estimated using several experimental techniques and models during the rainless summer. Evaporation was measured with an eddy covariance (EC) system consisting of a three-dimensional sonic anemometer and a Krypton hygrometer. Measurements of net radiation, air temperature and humidity, and water temperature enabled estimation of other energy balance components. Several models and energy balance closure were evaluated. In addition, evaporation from a class-A pan was measured at the site. EC evaporation measurements for 21 days averaged 5.48 mm day-1. Best model predictions were obtained with two combined flux-gradient and energy balance models (Penman-Monteith-Unsworth and Penman-Brutsaert), which with the water heat flux term, gave similar daily average evaporation rates, that were up to 3% smaller than the corresponding EC values. The ratio between daily pan and EC evaporation varied from 0.96 to 1.94. The bulk mass transfer coefficient was estimated using a model based on measurements of water surface temperature, evaporation rate and absolute humidity at 0.9 and 2.9 m above the water surface, and using two theoretical approaches. The bulk transfer coefficient was found to be strongly dependent on wind speed. For wind speeds below 5 m s-1 the estimated coefficient for unstable conditions was much larger than the one predicted for neutral conditions. © 2007 Elsevier B.V. All rights reserved.
Scientific Publication
נגישות
menu      
You may also be interested in