Evaporation Estimates in Front of Hurghada City by Using Penman-Monteith Equation, Red Sea, Egypt

摘要

Evaporation occurs simultaneously and this process depends on solar radiation, air temperature, relative humidity and wind speed. There is no any device for accurate direct measurement of evaporation from the sea surface, so many equations are used to estimate it from meteorological conditions. By using the Penman-Monteith equations, the daily evaporation rate of coastal water in front of Hurghada was estimated for four years (1999-2002). The result leading to the highest net evaporation occurred during the summers (June and July) and the lowest were in winters (January and December). The rates were fluctuating between 7.81-9.80 mm/day and net deposition occurred in winter months (January and November) and April, averaged between 2.48-5.05 mm/day. There is a direct proportion between net evaporation and air temperature and inversely proportional to the relative humidity. It is clear that the wind speed has affected on the evaporation rate. These consequences were similar to and conforms to previous researches, thereby the Penman-Monteith equations is desirable to estimate the evaporation rate of Hurghada coast.