Precipitable water

Precipitable water is the depth of the amount of water in a column of the atmosphere if all the water in that column were precipitated as rain. As a depth, the precipitable water is measured in millimeters or inches.

Measurement

There are different techniques:

• One type of measurement is based on the measurement of the solar irradiance on two wavelengths, one in a water absorption band, and the other not. The precipitable water column is determined using the irradiances in these bands and the Beer-Lambert law.
• The precipitable water can also be calculated by integration of radiosonde data (relative humidity, pressure and temperature) over the whole atmosphere.
• Data can be viewed on a Lifted-K index. The numbers represent inches of water as mentioned above for a geographical location.
• Recently, methods using the Global Positioning System have been developed.^[1]

External links

• Maurellis, A. N.; Lang, R.; van der Zande, W. J.; Aben, I.; Ubachs, W. (2000). "Precipitable water column retrieval from GOME data". Geophys. Res. Lett. 27 (6): 903–906. Bibcode 2000GeoRL..27..903M. doi:10.1029/1999GL010897. 
• Remote Sensing of Water Vapor From GPS Receivers

References