WMOD00296 ‎(2)‎

• Contract/Permit #: 14-06-D-5640
• Title: Park Range Atmospheric Water Resources Program Final Report
• Date: 9/30/1969
• Weather Modification - Doc Type: Report

~

During the 1968-69 operational season at the Park Range location, a Nike
Ajax radar at Mt. Harris and a GPG-1 radar at Lodwick were used to ob-
tain quantitative profile estimates of precipitation over the target area.
This was accomplished using a variation of the well known radar range
equation which is given by Battan (1960) as:

I;

P =
r

P + G2 >.. 2
t
(41T)3 R:

(1)

where

P
r

received power in Watts.

Pt = peak transmitted power in Watts.

G = Antenna Gain

>.. = Wave length of radar in cm.

a = Target backscatter cross section in cm2

Rt = Range to the observed target in cm.

The variation used for weather scatterers is accomplished according to
Atlas and Mossop (1960) by substituting for

'~

0' = NV

(2)

~

Here V is the pulse volume given by Handman and Davis (1964) as:

V:::

2
1T Rt e 0 h
8

e = horizontal beam width in radians

o vertical beam width in radians

h = the pulse length in space

-1
The quantity N is the reflectivity of the particles in cm and if expressed
in the usual form after Atlas and Mossop (1960) involving the reflectivity
factor Z is:

N =

10-121T5K2 Z
>..2

(3)

:

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