190 



SYNOPTIC RADIO METEOROLOGY 



-500 -400 -300 



-200 -100 100 



DISTANCE IN KILOMETERS 



200 300 



Figure 5.13. Idealized cold front in B units. 



The quantity, A, enables one to discern departures of A'^ structure from 

 the model atmosphere 



N = 313 exp \-f^\ 

 Further, the radio-ray bending, 



(5.9) 



Tl,2 = 



iV, 



N. 



cot e dN ' 10~', 



(5.10) 



where 6 is the local elevation angle of the radio ray to spherically stratified 

 surfaces of constant A'^, may be approximated by 



Tl.2 = — 



"^ 'eot d (IQ-^) 



Ai n 



dA{z, 313) + t(z, 313). (5.11) 



The term t{z, 313) is the bending in the average atmosphere given by (5.9), 

 while the integral term represents the departures in bending produced by 



