Pan evaporation is a measurement that combines or integrates the effects of several climate elements: temperature, humidity, rain fall, drought dispersion, solar radiation, and wind. Evaporation is greatest on hot, windy, dry, sunny days; and is greatly reduced when clouds block the sun and when air is cool, calm, and humid. [ 1 ]

2018年9月13日 · US Class A and D20 pans belong to the above ground pans, and GGI-3000 and 601B pans are the sunken pans. For the radiation processes, the pan water surface, side wall, and pan rim of the US Class A pan receive the irradiance; the pan water surface, side wall, pan rim, and pan bottom of the D20 pan receive the irradiance; GGI-3000 and 601B pans ...

1998年9月1日 · In hot arid environments, a sunken pan will overestimate evaporation from a nearby shallow lake/dam due to a larger surface roughness and consistently positive conduction heat flow across the pan–substrate boundary.

Gibson et al. (1999) have detailed evaporation pan-based models for determining δ A for three water balance situations: (1) a drying pan with no inflow, (2) a drying pan with precipitation...

Pan evaporation is a measurement that combines or integrates the effects of several climate elements: temperature, humidity, solar radiation, and wind. Evaporation is greatest on hot, windy, dry days; and is greatly reduced when air is cool, calm, and humid [1].

2018年3月5日 · Pan evaporation helps farmers determine how much water is needed for their crops. Pan evaporation is a weather measurement system that integrates several climatic conditions including rainfall, humidity, solar radiation, wind, temperature and drought dispersion. The system distinguishes the rates of evaporation based on the weather factor.

2013年4月17日 · Probably one of the oldest standardized pans is the Colorado Sunken Pan, going back to the work of Carpenter [1889, 1891] and Rohwer [1934]; it has a square water surface with sides of 91.5 cm (3 ft), a depth of 45.7 cm (1.5 ft), and its rim about 10 cm (4 in) above the surrounding ground surface.

2013年12月15日 · The new formulation explicitly considers the geometry of the pan (the pan diameter, the height of the water level and the height of the rim) in relation to the sun (solar zenith angle) as well as critical physical properties (albedo, emissivity, heat transfer) of the water surface and the pan wall.

There are five different evaporation pans such as, US Class A evaporation pan, ISI Standard evaporation pan, Colorado Sunken evaporation pan, USGS floating pan and small evaporation pan.

2018年3月25日 · Colorado Sunken Pan. This pan, 920 mm square and 460 mm deep is made up of unpainted galvanized iron sheet and buried into the ground within 100 mm of the top (Fig. 3.3). The chief advantage of the sunken pan is that radiation and aerodynamic characteristics are 5 to those of a lake. DISADVANTAGES: (i) difficult to detect leaks,