08
100
90;
~ FLIGHT 2488 (Il OCTOBER I960)
BOF
70
T
ALTITUDE (THOUSANDS OF FEET)
FLIGHT 2468 ( 7JUNE 1960)
60
50
40:
TROPOPAUSE
30
20
lO
20
1
L
30
40
1
50
L
=~ 60
PB ACTIVITY (yc /10° FT, AMBIENT)
4
-70
al.
-60
i
-50
4
-40
|
-30
TEMPERATURE(°C)
Fig, 1 -- Impactor-filter flights, Minneapolis, Minn.
-20