## Water Vapor Imagery

- Water vapor satellite imagery is derived from radiation emitted by water vapor at wavelengths which are not in an atmospheric window: 6 to 7 µm.
- If the upper troposphere is moist, radiation reaching the satellite will originate from this (cold) region and be displayed in light or nearly white shades.
- If the upper troposphere is dry, radiation will originate from water vapor at warmer levels and be displayed in darker shades.