"Brian Salt" wrote in message
k.co.uk...

It appears that the meteorologists used balloons as part of the data
collection, but at that time they had no radar, etc., to help with finding
the height of the balloon.
[...]
Does anyone have any idea how that could be done, given (as far as I can
see) that you need the horizontal distance to the balloon as well as the
angle to find the height? Or would the use of two theodolites
simultaneously, spaced at about 22 feet apart, allow the height to be
found without needing the horizontal distance?

TIA.


Known ascent rate of the pilot balloon (AKA pibal) and an azimuth/elevation
angle theodolite reading every 30 seconds plotted on polar graph paper will
produce a vertical wind profile. Trigonometry works, too.
--
TQ