DefinePK

Abstract

A clouds are one of the most principal elements in the energy balance which are played a significant role in the absorption and emission of thermal radiation. Data are taken by temperature, dew point, atmospheric pressure and height from satellites recorded by the European Centre for Medium- Range Weather Forecasts (ECMWF) for height (32-26509.7) meter the levels of pressure (1000-20) hpa, the choice of the characteristic day (12/2, 12/8, 12/14, 12/19, 12/22, 1/2, 1/8, 1/14, 1/19, 1/22, 2/2, 2/8, 2/14, 2/19, 2/22) of year 2016 over Baghdad station (33.375°N-44.375°E). Otherwise, we have studied long-wave radiation absorbed and emitted by clouds within certain wavelengths during hourly mean 00-12 times and a cycle in temperature variation. So, classified the clouds according to the cloud thickness and pressure levels as well as we studied the relationship between the cloud water content and the absorbance and relationship between the saturated vapor density and the emissivity. The results showed that absorption and emission depend on the cloud thickness, the cloud water content, saturated vapor density, cloud location and wavelengths, where the higher clouds absorption lead to clouds emission higher during hourly mean 00-12 time.