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The Freezing Level Height (HFL) is an essential parameter in meteorology, aviation, and in studying the rain-induced attenuation and cross-polarization. It is the level in the troposphere, where the temperature is 0 °C. The knowledge of HFL is also necessary to know the position of the radar bright band, which is of immense importance in radar meteorology and satellite communication. The measured HFL at several locations shows disagreement with those estimated using the ITU-R model. In this study, the authors wish to establish a model for the HFL. To perform this study, they obtained these values from the Integrated Global Radiosonde Archive (IGRA) over several locations in 35N-35S. To find the parameters that control the HFL, they chose a few location-centric parameters, viz. latitude (θ), height from the mean sea level (H), surface pressure (SP), surface temperature (ST), and relative humidity (RH). They investigated their correlations. They performed the study in three steps. At first, they studied the dependence of HFL on θ alone. Next, they studied its dependence as a function of θ and H. Next, they investigated its dependence under the simultaneous presence of ST, SP, RH, θ, and H. The paper presents the functional relationships of HFL with these parameters and suggests the most significant relations as the location-centric models of HFL. The models so established are used to estimate the HFL at some other geolocations and validated against the measured values obtained from the IGRA. The authors compare the estimated HFL values with those obtained using the ITU-R model. The authors compare the HFL values obtained from the precipitation radar onboard the Tropical Rainfall Measuring Mission (TRMM) satellite with those obtained from the ITU-R model over a few locations in India.
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