Atmospheric water plays a key role in climate. Water vapour is the most
important greenhouse gas and its condensed forms exert a profound
influence on both incoming solar and outgoing infrared radiation.
Unfortunately, accurate, height-resolved global-scale measurements of
atmospheric humidity are difficult to obtain. The change in
concentration of five orders of magnitude form the ground to the
stratosphere means there is no standard instrument that will measure
everywhere. This has led to different measuring techniques, all with
strengths and weaknesses.
This book assesses all presently available techniques that are used in
monitoring networks. Special weight is given to presenting the different
technical concepts, the accuracy of different sensor types, addresses
calibration issues and retrieval aspects.