A comparison of methods for estimating open-water evaporation in small wetlands
We compared evaporation measurements from a floating pan, land pan, chamber, and the Priestley-Taylor (PT) equation. Floating pan, land pan, and meteorological data were collected from June 6 to July 21, 2005, at a small wetland in the Canadian River alluvium in central Oklahoma, USA. Evaporation measured with the floating pan compared favorably to 12 h chamber measurements. Differences between chamber and floating pan rates ranged from −0.2 to 0.3 mm, mean of 0.1 mm. The difference between chamber and land pan rates ranged from 0.8 to 2.0 mm, mean of 1.5 mm. The mean chamber-to-floating pan ratio was 0.97 and the mean chamber-to-land pan ratio was 0.73. The chamber-to-floating pan ratio of 0.97 indicates the use of a floating pan to measure evaporation in small limited-fetch water bodies is an appropriate and accurate method for the site investigated. One-sided Paired t-Tests indicate daily floating pan rates were significantly less than land pan and PT rates. A two-sided Paired t-Test indicated there was no significant difference between land pan and PT values. The PT equation tends to overestimate evaporation during times when the air is of low drying power and tends to underestimate as drying power increases.
Citation Information
Publication Year | 2010 |
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Title | A comparison of methods for estimating open-water evaporation in small wetlands |
DOI | 10.1007/s13157-010-0041-y |
Authors | Jason R. Masoner, David I. Stannard |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Wetlands |
Index ID | 70138811 |
Record Source | USGS Publications Warehouse |
USGS Organization | Oklahoma Water Science Center; Toxic Substances Hydrology Program |