Remotely sensed specific humidity: Development of a derived product from the GOES Imager Channel 3

The analytic expression relating GOES-E/W chan nel 3 water-vapor radiance t o relative humidity is used along with upper-troposphere temperature observ ations to derive a high horizontal resolution brightness temperature produc t that correlates well with measured specific humidity. Moisture informatio n in raw water-vapor images is obscured by strong horizontal temperature gr adients in the upper troposphere. This information is exposed in the derive d product. Our results illustrate that the ability to remotely sense and re solve differences in water-vapor content increases with atmospheric dryness .