Lake Evaporation Using the Hamon Method

This model demonstrates the application of the Hamon method, as described in a USGS report[1], to estimate daily evaporation from a lake surface. The Hamon method is a widely used approach for calculating evaporation based on climate drivers such as air temperature, solar declination, and maximum daylight hours. The method involves the following key steps:

1. Solar Declination and Daylight Hours: Calculated based on latitude and Julian day, these parameters represent the seasonal variation in solar energy reaching the Earth's surface.
2. Saturation Vapor Pressure and Density: Derived from the average daily air temperature, these values reflect the capacity of the air to hold moisture.
3. Evaporation Estimation: Combines saturation vapor density and maximum daylight hours to compute the daily evaporation rate.

References:
1. Tollett, R. W., & Bekele, E. G. (2012). Comparison of evaporation computed using the complementary relationship Lake Evaporation Model and evaporation-pan data for five reservoirs in Texas, 1965-2009 (Scientific Investigations Report 2012-5202). U.S. Geological Survey. https://pubs.usgs.gov/sir/2012/5202/pdf/sir2012-5202.pdf

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