HR: 14:10h
AN: G42B-03 INVITED [PDF]
TI: Accuracy Requirements for Moisture Observations Using Space Geodetic Techniques
AU: * Gutman, S I
EM: Seth.I.Gutman@noaa.gov
AF: NOAA Research-Forecast Systems Laboratory, 325 Broadway R/FS3, Boulder, CO 80305-3328
AB:
Most of our information about the structure and variability of moisture in the atmosphere comes from three operational
sources: radiosondes, surface measurements of dew point temperature (convertible to relative humidity), and satellite
measurements of brightness temperature in the infrared and microwave portions of the electromagnetic spectrum. These
observing systems function synergistically, since no one system provides all of the information required for weather
forecasting, climate monitoring, and scientific research. Notwithstanding the strengths of the operational composite
moisture observing system, its shortcomings preclude significant advances in weather prediction, our understanding of
atmospheric processes, and climate monitoring and prediction. In recent years, the use of space geodetic techniques for
atmospheric remote sensing has been proposed, demonstrated and verified. Space geodetic techniques, especially techniques
using the Global Positioning System, have certain attributes that strongly complement both operational (or soon to be
operational) and research observing systems. NOAA's Forecast Systems Laboratory in Boulder, Colorado, has been evaluating
techniques to retrieve integrated (total atmospheric column) precipitable water vapor (IPW) from zenith tropospheric signal
delays since 1994, and use IPW in operational weather forecasting since 1997. As a result of these evaluations, the use of
ground-based GPS-Met is expected to become operational within the National Weather Service over the next few years. However,
space geodetic techniques will neither replace conventional observing systems, nor will they completely mitigate their
deficiencies. In this talk, I will review the requirements for water vapor measurement accuracy, and show that this is
application dependent. I will then discuss the strengths and weaknesses of the more common operational moisture sensing
systems, and examine the attributes of some space geodetic techniques in this context.
UR: http://gpsmet.noaa.gov
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 1200 GEODESY AND GRAVITY
SC: Geodesy [G]
MN: 2003 Fall Meeting