Energy budget evaporation from Williams Lake: A closed lake in north central Minnesota

Abstract

Evaporation from Williams Lake, computed by the energy budget method for the five open‐water seasons of 1982–1986, varied from a maximum seasonal rate of 0.282 cm/d in 1983 to a minimum seasonal rate of 0.219 cm/d in 1982. The pattern of monthly values of evaporation is not consistent from year to year. The normally expected pattern of low evaporation values in May, followed by increasing values in June to maximum values in July is true for only 3 of the 5 years. Comparison of annual evaporation calculated by the energy budget and mass transfer methods indicates that energy budget values varied from 13% greater to 11% less than mass transfer values. Furthermore, there is no seasonal bias in the pattern. Large differences exist in the magnitude of energy fluxes to and from Williams Lake. By far the greatest energy fluxes, having magnitudes of hundreds of watts per square meter, are incoming solar radiation, incoming atmospheric radiation, and outgoing long‐wave radiation emitted by the lake water. The least energy fluxes are related to advection, which generally have magnitudes less than 5 W m−2.

Hydrological and chemical estimates of the water balance of a closed‐basin lake in north central Minnesota

“…The relation of water budget components to one another presented in Figure 7 If seepage were ignored, or if seepage to the lake and from the lake were equal, annual change in lake volume might be explained solely by differences in precipitation and evaporation (Figure 7). Change in lake volume also might be explained primarily by differences between seepage to the lake and seepage from the lake if precipitation were equal to evaporation, which could be expected for this part of Minnesota [Sturrock et al, 1992]. The annual volume represented by the decline in lake level (dV) was nearly the same as the difference between groundwater seepage to the lake and seepage from the lake (GWI -GWO) (Figure 7).…”

“…Two of the hydrological fluxes associated with lakes most difficult to quantify are evaporation [Sturrock et al, 1992] and seepage to and from groundwater [Winter, 1978]. The degree of uncertainty in hydrological measurement of these fluxes has been verified using stable isotopes for evaporation [Lewis, 1979] and seepage [Dincer, 1968 [Stauffer, 1985], which are conservative elements within their study lakes.…”

“…During the time when the lake was not ice covered, evaporation was determined by the energy budget method, which relates changes in energy storage within the lake to net transfer of energy into and out of the lake [Sturrock et al, 1992]. Vapor pressure, wind profiles, air temperature, and water temperature of the lake surface were measured on a raft near the middle of the lake.…”

“…Incoming long-and short-wave radiation was measured on land near the tipping-bucket rain gage. Field and analytical methods used to determine evaporation are described by Sturrock et al [1992]. During periods when the lake was ice covered, loss due to evaporation and sublimation was determined by a mass transfer technique using monthly averaged climate data and calculated atmospheric and ice surface vapor pressure.…”

Carbon budget for a groundwater-fed lake: Calcification supports summer photosynthesis

“…l), for this analysis because continuing efforts by the U.S. Geological Survey and its Minnesota cooperators have produced an unusually good data base of lake chemistry and biology, groundwater exchanges with surrounding calcareous glacial terrains, gas exchanges with the atmosphere, and water and energy budgets (e.g. Sturrock et al 1992;Rosenberry et al 1993). The choice of Williams Lake does not exaggerate the importance of marl precipitation; the lake is less marly than some other lakes in the region, lacks the obvious groundwater seeps and springs often associated with marl formation, and has lower calcium and alkalinity concentrations than such lakes.…”