————— 
PRESENT STATE OF OUR KNOWLEDGE OF THE UPPER ATMOSPHERE. 99 
distribution and for the undue influence of Pavlovsk, we obtain, as cor- 
vected values for the gradients in the two cases, the following values :— 
Pressure | Pressure | | | 
| <750 >770 “ey: punto eg 9 Se ee len Eaaliy 
0 | 81°8 78°4 80°1 | 80:0 
5'1 06 
1 16-7 DUS, it 77:0 771 
65 Bia | | 
2 | 70°2 74:1 [27 72:8 
5'6 4°8 
3 64:6 69°3 67°5 67:6 
(oem (ees 
4 i. | 58:2 63°5 61:7 61°8 
| 6:3 6:4 
oie | 51:9 571 55:4 55° 
| 64 67 
6 45°5 50°4 48°6 48°7 
70 72 
7 | 38°5 43-2 41-4 41-5 
6°6 76 } 
8 31:9 35°6 34:0 34-1 
4:5 74 
9 | 27°4 28°2 27-2 27°3 
3-4 | 5-9 
10 | 24:0 22:3 22:2 22°3 
17 | 48 
11 | 22:3 17-5 19:0 19-0 
o1"} 2:8 
12 22:2 14:7 18:7 18°3 
| —1-2 1-0 
iB} 23-4 13:7 19°7 19°1 
| 0°3 —0°5 
14 | | 23-1 14-2 19°6 191 
The column T, gives the corrected mean temperature for pressure 
<750, T, that for pressure> 770, T; is the approximate mean tempera- 
ture of the intermediate regions deduced from T,, T,, and the general mean 
T,, on the assumption that the influence of T,, T, in forming the general 
mean is approximately proportional to the number of observations. The 
result is interesting as showing that anticyclonic regions are not only 
warmer than regions of low pressure, but also warmer, up to 10 km., than 
the intermediate regions, which appear to be colder at 9-10 km. than 
regions of high or low pressure. 
If, in the centre of an anticyclone, 6 is the excess of pressure at any 
height above the normal pressure B for that height, and p is the density 
there, the value of the ratio b/pd may be taken as a measure of the intensity 
of the anticyclone, where d is the mean distance of the isobar B from the 
centre of the anticyclone. Now as long as the temperature near the centre 
of an anticyclone remains higher than that in surrounding regions, 
the value of b/pd increases with increasing height, and consequently the 
anticyclone increases in intensity. If 6,, d,, are corresponding quantities 
for a cyclone, b,/pd, increases with increasing height so long as the cyclone 
is colder than its surroundings. The values found above indicate that 
this is the case up to 8-10 km. Even at 14 km. the pressure over the 
anticyclonic region exceeds that over the cyclonic by more than 1 mm., 
which is as efficient in producing motion as a difference of 7 mm. at the 
H 2 
