Satellite Method Measures Water Vapor

U.S. government scientists say they’ve discovered satellite technology that overcomes an obstacle to measuring atmospheric water vapor from space.

When viewing the atmosphere above land obscured by clouds, satellites often have trouble measuring how much water vapor is present from the Earth’s surface to the top of the atmosphere — a quantity known as precipitable water vapor.

Now Merritt Deeter and colleagues at the National Center for Atmospheric Research have used a microwave radiometer aboard NASA’s Aqua spacecraft to determine precipitable water vapor.

The researchers said the new approach has little sensitivity to clouds and works during day and night and over ocean and land surfaces.

Deeter noted water vapor is an important factor because of its role as a greenhouse gas and its relationship to clouds and precipitation.

The study is presented in the journal Geophysical Research Letters.