Backscatter characteristics of burnt straw particles

Strong radar echoes from targets a few kilometres across have been found in the absence of rain, and were attributable to burnt straw particles rising from large field fires. The echoes showed a marked difference of reflectivity between horizontally and vertically polarised radar transmissions. This paper describes the way the reflectivity and differential reflectivity with polarisation are distributed in space, gives a theoretical model to explain these effects, and analyses the basic propagation characteristics.