RADAR STORM DETECTION 
determine roughly the average rain intensity over the 
path [15]. 
Conclusion 
Although the theory of storm detection is fairly 
straightforward, the complexities of computation from 
the Mie theory still leave some discrepancies in the 
amount of reflection to be expected from various pre- 
cipitation elements and in the values of attenuation. 
For the purpose of determining quantitatively the tar- 
get characteristics of a storm, a greater source of error 
lies in the inaccuracies in measuring the power received 
at the radar. More exact measurements may open up a 
new field of estimating the rain intensities of distant 
storms and of making quantitative studies of the growth 
processes of precipitation along the vertical. 
It would be particularly desirable to measure the 
rate of decrease with altitude of the signal strength 
from different clouds of varying depths, precipitation 
intensities, and atmospheric conditions. Such measure- 
ments would give information on the growth of precipi- 
tation particles by diffusion and the magnitude of the 
coalescence effects. Observations of the type, mass, 
and fall velocity of snow that reaches the ground would 
give considerable supplementary information for an 
understanding of the physics of precipitation. 
Simultaneous radar and visual (theodolite) observa- 
tions of cumuliform clouds, similar to those carried out 
by Workman in New Mexico, should also lead to a 
better understanding of thunderstorms. Fruitful re- 
search problems are (1) the rate of rise of the visual 
top as related to the echo top in growing thunder- 
storms, (2) coagulation and chain reaction effects in the 
heavy rain, again as revealed by the rate of decrease 
with altitude of signal strength, and (3) the characteris- 
tics of precipitation echoes during the formation of the 
bright band in the degenerate stages of the thunder- 
storm, as revealed by radarscope photographs taken 
with reduced gain. Although many complexities in the 
individual storms present themselves in the study of 
such problems, the complexities themselves offer fruit- 
ful paths of research. The ever-changing panorama of 
1289 
weather is nowhere better revealed than on the radar 
screen. 
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