Towards Understanding the Influence of Vertical Water Distribution on Radar Backscatter from Vegetation Using a Multi-Layer Water Cloud Model

For a good interpretation of radar backscatter sensitivity to vegetation water dynamics, we need to know which parts of the vegetation layer control that backscatter. However, backscatter sensitivity to different depths in the canopy is poorly understood. This is partly caused by a lack of observational data to describe the vertical moisture...

A comparison between support vector machine and water cloud model for estimating crop leaf area index

The water cloud model (WCM) can be inverted to estimate leaf area index (LAI) using the intensity of backscatter from synthetic aperture radar (SAR) sensors. Published studies have demonstrated that the WCM can accurately estimate LAI if the model is effectively calibrated. However, calibration of this model requires access to field measures...

Impact of Soil Moisture and Vegetation Water Content on Backscatter Simulated by WCM at Different Radar Parameters in Maize Field

This paper analysis the effects of soil moisture and vegetation water content (VWC) on total backscattering (σ_tot^0) simulated by water cloud model (WCM) throughout a growth cycle of maize at different frequencies, polarization modes, and incidence angles. Firstly, the bare soil backscatter (σ_soil^0) was simulated by Integral Equation Method ...

Retrieval of liquid water cloud properties from ground-based remote sensing observations

Accurate ground-based remotely sensed microphysical and optical properties of liquid water clouds are essential references to validate satellite-observed cloud properties and to improve cloud parameterizations in weather and climate models. This requires the evaluation of algorithms for retrieval of cloud microphysical and optical properties...

Diurnal differences in vegetation dielectric constant as a measure of water stress

Currently, vegetation is considered a barrier to soil moisture retrieval by both passive and active remote sensing missions. Microwave emission and backscattering of vegetation is driven by the vegetation dielectric constant, which is a function of vegetation water content. The latter is a measure of root zone water availability. Understanding...

The impact of droplets’ clustering on the radar backscattering from water clouds

The goal of this thesis is to investigate the clustering effect of droplets in the water clouds. The initial motivation came from the incapability of millimeter-wave cloud radars to always detect low-level liquid water clouds. The observed discrepancy between the value of radar reflectivity factor estimated by radar measurements and the...

Scattering in Water Clouds: The Impact of the Spatial Correlation of Particles on The Backscattered Mean Power

In the present work scattering theory in water clouds has been studied. Alternative forms for Maxwell equations have been developed and discretized in order to calculate backscattered mean powers from cloud particles. With simplified discretized equations the backscattered electric field has been approximated for a single particle. This...