Observation of bright-band height data from TRMM-PR for satellite communication in South Africa

Observational study on melting layer characteristics over Palau in Pacific Ocean

In the tropical region, convective rain is a dominant rain event. However, very little information is known about the convective rain melting layer. In this paper, S-band dual-polarized radar data is studied in order to identify both the stratiform and convective rain melting layers in the tropical region, with a focus on the convective events. By studying and analyzing the above-mentioned two types of rain events, amongst three radar measurements of reflectivity ( Z ), differential reflectivity ( Z DR ), and cross correlation coefficient ( ρ HV ), the latter one is the best indicator for convective rain melting layer detection. From two years (2014 and 2015) of radar and radiosonde observations, 13 convective rain melting layers are identified with available 0 °C isothermal heights which are derived from radiosonde vertical profiles. By comparing the melting layer top heights with the corresponding 0 °C isothermal heights, it is found that for convective rain events, the threshold to detect melting layer should be modified to ρ HV = 0.95 for the tropical region. The melting layer top and bottom heights are then estimated using the proposed threshold, and it is observed from this study that the thickness of convective rain melting layer is around 2 times that of stratiform rain melting layer which is detected by using the conventional ρ HV = 0.97 .

Characterization of S-Band Dual-Polarized Radar Data for the Convective Rain Melting Layer Detection in A Tropical Region

The effects of rain on terrestrial and satellite communication systems, especially at frequencies above 10 GHz, have been statistically dealt with at length. It is also well known that rain height plays an important role in signal fading and co-channel interference due to scattering. The rain height is directly related to the 0°C isotherm. At this height hydrometeors change from solid to liquid state in the melting layer, increasing their reflectivity and causing the bright band effect in radar measurements. The bright band is defined by the top, bottom and maximum reflectivity heights. The peak reflectivity height can be obtained from radar volume scans. This paper presents a statistical characterization of the time and space variability of the maximum reflectivity height during stratiform rain events. This paper also focuses on the dependence between simultaneous meteorological parameters derived from weather radar and from surface automatic weather observation stations at local scale in a temperate climate region. The data used in this study was obtained from 2006 to 2011.

Characterization of Maximum Radar Reflectivity Height During Stratiform Rain Events

This paper presents a methodology for estimating rain lengths over slant paths derived from volumetric structures of rain cells. The space distribution of rain is obtained from meteorological volumetric radar data. Case studies for stratiform and convective rain distributions are analyzed. Estimation of height and length of rain is discussed for observed events. The spatial and temporal variability with different elevation angles are also analyzed. Finally a version of the implemented algorithm is presented in order to use it in generating time series rain lengths that can lead to a long term statistical study of the rain effective lengths variability for different paths.

Estimation of effective path lengths of rain based on cell size distributions from meteorological radar

In order to evaluate precisely the additional rain loss due to precipitation in the design process of Earth-Space telecommunication systems, it is necessary to obtain the effective rain length with the major possible resolution. The aim of the study is the precise determination of 0°C isotherm height and the boundaries of the bright band in rain situations, based on meteorological radar measurements. In order to identify data affected by bright band in weather radars, as well as to determine bright band height, some algorithms have been applied for the previously characterized Vertical Profiles of Horizontal and Differential Reflectivity.

http://ieeexplore.ieee.org/iel5/4977244/5067558/05068377.pdf

M. Maruri

Papers

Characterization of Maximum Radar Reflectivity Height During Stratiform Rain Events

Estimation of 0°C isotherm height from vertical profiles of reflectivity in raining earth-space paths