Se 
better methods of measuring velocity are needed, however. It may be 
possible to drop sonic bouys onto the bottom and use them for ranging. 
The gravity and magnetic fields deserve more investigation in 
this region. Gravity must be well known in this region to describe the 
crustal features. Magnetic studies should continue to be directed both 
toward geological anomalies and toward rapid field variations. 
New techniques should be used to find the ways in which the Arctic 
Ocean resembles or differs from the other oceans of the world. One 
measurement deserving immediate consideration is the vertical heat flow 
from the Arctic Ocean floor. A "thermograd" instrument has been developed 
at Lamont for this purpose and has been used successfully in other oceans. 
The circulation of sea water may be studied by radiocarbon 
dating of the various water masses. This has not yet been done systematically. 
Circulation in the Arctic Ocean and its exchange with Atlantic waters is 
undoubtedly extremely important for world climate and deserves concentrated 
studye 
Wave motion in the Arctic Ocean is of much longer period than 
that found in open seas. This wave motion has received some theoretical 
treatment but further experiment is needed. Tripartite arrays of long- 
period seismometer could be used to find the directional spectrum of these 
waves. Such seismometers might also detect minor earthquakes in the Arctic. 
The submarine geology of this ocean is only beginning to be 
known. The depth of the crust has not yet been measured and should be 
one of the first objectives for future work. The depth to the Mohorovicic 
discontinuity has special interest since it is claimed by some USSR geologists 
that the Arctic Ocean is a portion of sunken continent. If so we might expect 
a thicker crust than is normal for ocean basins of this size. Preliminary 
refraction seismic work at Alpha indicated that the Arctic Ocean may not 
differ greatly in crustal structure from other oceans. 
