Measuring Atmospheric Water Vapor

• Water Vapor data from Ramey School, Aguadila, Puerto Rico
• Water Vapor Protocol (Spring 2003 GLOBE version)
• Water Vapor Data Sheet (Spring 2003 GLOBE version)
• Online version of NASA Educators Guide:
  Brooks, David R., Mims, Forrest M. III, Arlene S. Levine, Dwayne Hinton. The GLOBE/GIFTS Water Vapor Monitoring Project: An Educator's Guide with Activities in Earth Sciences. NASA EG-2003-12-06-LARC, 2003.
• E-mail data entry format for reporting water vapor data
• Calculating precipitable water (PW) from dewpoint temperature, as discussed in the Water Vapor Protocol.
• Calculate dewpoint temperature from air temperature and relative humidity.
• Calculate precipitable water vapor (PW) based on your measurements with a GLOBE/NASA water vapor sun photometer
• Participate in the GLOBE water vapor instrument calibration project
• Here is an introduction by the American Geophysical Union to the relationship between atmospheric water vapor and Earth's climate: Water Vapor in the Climate System, Special Report, December 1995.

The two-channel water vapor instrument shown here is physically identical to the two-channel visible light sun photometer for measuring aerosol optical thickness. It uses two near-IR detectors instead of the LEDs used in the visible-light version. Protocols for using this instrument were written for the GLOBE program in the mid-1990's. However, the GLOBE program no longer actively supports this protocol. IESRE currently has no independent source of data for calibrating these instruments. If you are near a NOAA GPS-MET or NASA AERONET site, you can calibrate them yourself. (See the link to "Participate in the GLOBE water vapor instrument calibration project." Even though this is no longer a GLOBE project, the procedure remains the same.) These instruments can be purchased from IESRE, aligned but not calibrated, for $180.