By measuring the shift of the frequency very precisely, astronomers estimate the speed and direction of moving gas. (alma-telescope.jp)
Moving with the flow, they often use the momentum and direction of moving air mass and sea waves to gently steer their vessels into narrow slips. (franklintempleton.com)
DopplerScat adds a doppler radar to the package, allowing scientists to measure the speed and direction of the moving water. (earthobservatory.nasa.gov)