Scientific Investigations Report 2006-5252
U.S. GEOLOGICAL SURVEY
Scientific Investigations Report 2006-5252
Evaporation from Lake Mead, Arizona and Nevada, 1997–99
Prepared in cooperation with the Bureau of Reclamation
By Craig L. Westenburg, Guy A. DeMeo, and Daron J. Tanko
Table of Contents
Conversion Factors, Datums, and Acronyms
and Symbols
Abstract
Introduction
Estimating Evaporation from Lake Mead
Previously Reported Evaporation Rates
Alternative Methods of Estimating
Lake Mead Evaporation
Summary
Acknowledgments
References Cited
Figures
Figure 1. Location of study area and
evaporation stations, Lake Mead, Arizona and Nevada.
Figure 2. Four floating platforms on
Lake Mead.
Figure 3. Lake Mead daily water-level
elevation and date of station installation, February 1997–December 1999.
Figure 4. Instrument configuration
on floating platforms on Lake Mead, Arizona and Nevada, and of energy fluxes
at water surface.
Figure 5. Air temperature, water temperature,
and relative humidity collected at four floating instrumented platforms on Lake
Mead, Arizona and Nevada, 1999.
Figure 6. Air temperature, water temperature,
and relative humidity collected at the Sentinel Island evaporation station,
Nevada, 1997–99.
Figure 7. Wind speed and direction
at four floating instrumented platforms on Lake Mead, Arizona and Nevada, 1999.
Figure 8. Daily evaporation rates at
four floating instrumented platforms at Lake Mead, Arizona and Nevada, 1999.
Figure 9. Total and average monthly
evaporation at three floating instrumented platforms on Lake Mead, Arizona and
Nevada, 1997–99.
Figure 10. Comparison of total monthly
evaporation at four evaporation stations with average monthly evaporation
at all stations and three open-water evaporation stations with average monthly
evaporation at open-water stations, April 1998–October 1999. R is correlation
coefficient.
Figure 11. Annual Lake Mead evaporation,
1953–94.
Figure 12. Regression of monthly average
net radiation at the Water Barge Cove station and total monthly evaporation
at Sentinel Island station for: January through May 1997–99 and June
through December 1997–99. R2 is coefficient of determination.
Figure 13. Total monthly evaporation
(average of open-water stations) and total monthly evaporation computed from
monthly average net radiation at the Water Barge Cove station.
Figure 14. Comparison of total monthly
evaporation (average of open-water stations) and monthly evaporation computed
from monthly mean net radiation at the Water Barge Cove station.
Tables
Table 1. Average maximum and average
minimum air temperature and average annual precipitation at Las Vegas and Overton,
Nevada, 1961–90.
Table 2. Site information for four floating
instrumented platforms used to collect data to compute evaporation from Lake
Mead, Arizona and Nevada, 1997–99.
Table 3. Description of data, collected
at four floating instrumented platforms, used to compute evaporation from Lake
Mead, Arizona and Nevada, 1997–99.
Table 4. Number of months with complete
data, collected at four floating instrumented platforms, used to compute evaporation
from Lake Mead, Arizona and Nevada, 1997–99.
Table 5. Monthly mean meteorological
and water-temperature data measured at four floating instrumented platforms
on Lake Mead, Arizona and Nevada, 1997–99.
Table 6. Total and average monthly evaporation
from Lake Mead at four floating instrumented platforms, Arizona and Nevada,
1997–99.
Table 7. Average monthly evaporation
and computed monthly evaporative loss from Lake Mead, Arizona and Nevada, July
1997–December 1999.
Table 8. Total monthly, total annual,
and average monthly Lake Mead evaporation, 1953–95.
This report is available online in Portable Document Format (PDF). If you do
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Send questions or comments about this report to the author, Craig L. Westenburg, (702) 564-4610.
For more information about USGS activities in Nevada, visit the USGS
Nevada Water Science Center home page.
U.S.
Department of the Interior | U.S. Geological
Survey
