"Mr Blowman" S@not here.karoo.co.uk wrote in message
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"Mr Blowman" S@not here.karoo.co.uk wrote in message
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"Steve" wrote in message
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"Mr Blowman" S@not here.karoo.co.uk wrote in message
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To calculate thickness values in DAM I have always used the eqution
(1000mB - SLP ) * 0.87 )+ 500 mB height. Is this correct as I cannot
explain the 0.87 constant factor.

Decrease in pressure with height is 1hPa per 0.87 dam, roughly.


Do you have an official source available as a link, thanks in advance .



No it was OTTOMH, but you could try searching for "degridding" in the FAQ