APPENDIX C 75 



180 150 120 90 60 30 



30 60 90 120 150 BO 



60- 



60 



70 1 



180 150 



LA2 



—170 

 180 



120 90 60 30 30 



60 90 120 150 



Figure C-23. Percent of time gradient < — 157 (N/fcm): May. 



180 150 



80 



60- 



60 



70 



70 1 



180 !50 120 90 60 30 



30 60 90 120 150 180 



Figure C-24. Percent of ducting layers thicker than 100 m: May. 



