WORLD WEATHER NETWORK 707 
can be achieved along these lines before the whale uring winds and other conditions below the aircraft 
becomes extinct. Aircraft reconnaissance has proved down to the surface gives promise that such techniques 
exceedingly valuable, particularly for special atmos- will be in routine use fairly soon. The occupation o 
pheric phenomena such as hurricanes and typhoons, surface stations, however, still remains essential. In 
and also in its contribution to the knowledge of meteoro- regions very far from land in the Southern Hemisphere, 
Fie. 2—Ocean ar e aving less than 500 ships’ Fre. 3—Ocean areas (shaded) more than 600 nautical miles 
observati 0-yr period ending in 1933. from land and having less than 500 ships’ observations in 
fifty years. 
logical conditions in areas which cannot yet be covered ‘ : : 
by ordinary observational means. An example of this is 7¢raft reconnaissance would not be an economical 
the regular weather flight from Alaska to the North WY of obtaining the information. Stationary weather 
Pole. It is important, however, to remember that to ships are a most satisfactory solution, except for the e 
be fully effective aircraft reconnaissance of this latter cessive cos t of their maintenance if ordinary vessels a 
type needs to be coordinated more closely with surface used for this purpose. The requirement, therefore, is fo 
observations. Therefore, as is well illustrated by the specially designed floating vessel, manned or unmanne 
North Pole flights, there is still a need for sea-level which can be suitably anchored even in great depths of 
observations. The development of techniques of meas- water. Work along these lines has proceeded as far as 
