WV4_DEGC.TXT Specification for the data file

This file includes a few select data points from the last 48-hours of GOES satellite data.
These points support microwave terrestrial propagation studies. The file has 96 lines of 
data and the current data line is appended to the end of the file each half hour, and the 
oldest line at the beginning of the file is dropped at the same time.

Each line of data is computed from the current satellite image at 
http://sat.wrh.noaa.gov/satellite/4km/WR/WV4.GIF. 

Here is a sample line:

2007_12_20_0859 12/20 08:30 W7PUA-W7CQ -42.2 KD7TS-W7LHL -47.7 KD7TS-W7SZ -48.8 W7LHL-W7SZ -47.7 KD7TS-W7CQ -46.6 W7LHL-W7CQ -45.5 KSLE -45.5 KUIL -39.0 

This line consist of three fields relating to time and date, followed by a variable number
of "Pixel Location Names" and "Temperature, Celsius" data pair fields.
  
All fields are space separated, and defined as follows:

2007_12_20_0859   UTC date-time stamp of the this line append to the file
12/20             Month / day, read from the wv4.gif image
08:30             Time in 24 hour UTC format, read from the wv4.gif image
W7PUA-W7CQ        Name of first data pair
-42.2             First temperature, Celsius, at mid-point pixel
KD7TS-W7LHL       Name of second data pair
-47.7             Second temperature, Celsius, at mid-point pixel
  ----  Five pairs omitted here  ------
KUIL              Name of last data pair
-39.0             Last temperature, Celsius, at balloon launch site

All temperatures are read from the WV4.GIF image that is derived from the GOES weather 
satellite 6.7 um IR channel. Roughly speaking, this is the measured temperature of the 
air at the top of significant water vapor in the atmosphere. As expressed by the 
meteorologists at Colorado State University, "The water vapor channel senses radiation 
emitted from high clouds and upper level water vapor."
  
See: 
http://www.cira.colostate.edu/cira/RAMM//rmsdsol/main.html
as well as searching the Net for Water Vapor Imagery for more information.

For reference, the wv4.gif X Y pixel locations are:
W7PUA & W7CQ - pixel 234 164
KD7TS & W7LHL - pixel 236 117
KD7TS $ W7SZ - pixel 239 128
W7LHL & W7SZ - pixel 240 131
KD7TS & W7CQ - pixel 235 140
W7LHL & W7CQ - pixel 236 144
KSLE weather balloon in Salem Oregon - pixel 235 152
KUIL weather balloon in Quillayute Washington - pixel 199 105

Written 20 Dec 2007, updated 21 Dec 2007 
by W7CQ and W7PUA.