118 A WORLD ATLAS OF ATMOSPHERIC RADIO REFRACTIVITY 



180 150 120 90 60 30 30 60 90 120 150 180 



180 150 120 90 60 30 30 60 



120 150 180 



Figure D-2. Tropopause heights {km), based on temperature lapse rate: May. 



180 150 120 90 60 30 



30 60 90 120 150 180 



Figure D-3. Tropopause heights (km), based on temperature lapse rate: August. 



