RADAR STORM OBSERVATION 
3. Facsimile transmission of the PPI-scope display. 
4. Remote scopes, distant from the radar, which get 
the video information either by wire or radio signals. 
The first method is used at present and will continue 
to be the most practical for a while [59]. The fourth 
method has been used for remote presentation of scope 
information for military purposes; but it is expensive 
and somewhat limited in range [71]. Television is out 
of the question for the present and the immediate future 
because of lack of facilities. 
Facsimile transmission of PPI photographs presents 
intriguing possibilities: first, facilities for facsimile trans- 
mission are presently available at many military and 
civilian weather stations; second, the facsimile record 
presents the recipient with a permanent picture of the 
scope (which television and remote scopes do not); and 
third, facilities for facsimile transmission between 
ground and aircraft have been nearly perfected. The 
main difficulty at present is getting a PPI picture to 
transmit, although this problem is practically solved in 
several ways. One way is by use of the fast develop- 
ment techniques (Polaroid Land Camera). A second way 
is by use of PPI tubes with very slow decay time phos- 
phors. A third way is through the use of fast special 
papers such as Alphax.* Other more elegant and elab- 
orate methods have also been suggested. 
Research in Physical Meteorology. It is anticipated 
that radar will provide useful information concerning 
the structure and behavior of that portion of the atmos- 
phere which is not covered by either micro- or synoptic- 
meteorological studies. We have already observed with 
radar that precipitation formations which are undoubt- 
edly of significance occur on a scale too gross to be 
observed from a single station, yet too small to appear 
even on sectional synoptic charts. Phenomena of this 
size might well be designated as mesometeorological. 
In addition to supplying observations in this meso- 
meteorological region, radar is also expected to be of 
assistance to the physical meteorologist in his studies 
of the mechanism of precipitation; of the size and num- 
ber distribution of hydrometeors; and of the behavior of 
hydrometeors under various conditions of turbulence. 
It may also provide him with clues concerning the proc- 
esses of waterdrop and snowflake growth, coalescence, 
and evaporation. 
Sincere and deep-felt appreciation is expressed to 
members of the M. I. T. Weather Radar Research 
Project; their helpful comments, corrections, and sug- 
gestions were of invaluable assistance in the prepara- 
tion of this article. For permission to use photographs, 
the author is indebted to the U. S. Navy Department 
and to the M. I. T. Weather Radar Research Project 
operating under Signal Corps Contract W236-039-sc- 
32038. 
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10. 
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