Figure 7
Map of the Veff-ratio. The color shows the expected Veff-ratio for propagation with respect to the explosion site, as if the respective point on the map was the hypothetical turning point of a stratospheric ray (effective sound speed at ground is the value at the explosion site into the respective direction). Note that in order to have a detection at the surface the corresponding turning point would be approximately halfway in between the detection point and the explosion site. The map clearly indicates that for the study area the ECMWF model only predicts Veff-ratios smaller than one. A star denotes the explosion site; positive detections are marked by black polygons.
