BIRDTAM composite

This page provides the last available radar composite of biomass (birds and insects) through the lowest air layer (roughly below 1 km) of Germany, the Netherlands and Belgium. The density of birds and insects is expressed as BIRDTAM values as used in aviation. BIRDTAM values follow a logarithmic scale from 0-8, extended here with 9 and >9 to discriminate between mass migration and rain. BIRD and INSECT reflections are shown in green, yellow, orange, red and sometimes even darker colors; RAIN as large, sharply delimited, black- or dark-coloured areas; and GROUND CLUTTER (e.g. mountains) as small dark areas (e.g. in S and SE Germany, E Belgium). Note that the radar is sampling higher altitudes with increasing distance from the radar, due to the curvature of the earth. For now, these have not been corrected for.