One of the early methods of finding out what was going on in the atmosphere in order to understand the weather is still to be bettered. Balloons partly filled with helium or hydrogen with gadgets called radiosondes attached are released from fixed points. As they rise at about 300 metres a minute, the radiosondes transmit pressure readings, temperature, relative humidity and position every second.
They remain a valuable aid in weather forecasting.
Eventually, at about 18 miles high, the balloon swells so much in the thinner atmosphere that it bursts and the tiny transmitter falls back to earth.
These balloon-borne radiosondes give readings that are cannot be obtained any other way, and are suspended far enough below the balloon to avoid the signals being distorted.
A variation of these, called dropsondes, are launched out of aircraft, particularly by the crews of the Facility for Airborne Atmospheric Measurements planes based at Cranfield, Bedfordshire.
When airborne scientists are flying high above menacing storm clouds, like the ones recently seen over Cumbria, dropsondes are launched out of a tube in quick succession.
They then parachute through the storm cloud, sending signals directly to the Met Office so the severity of the weather that is on the way to the UK can be measured.
As many as four devices can be in various stages of descent at once, giving a comprehensive idea of what is going on within the storm clouds.
At £500 a time, this is not a cheap operation, but with more severe storms predicted this could save much more money if accurate early warnings of flooding are given.
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