GRAS A Spot

GRAS

GRAS A Spot
GRAS A Spot

The main objectives of the GNSS (Global Navigation Satellite System) Receiver for Atmospheric Sounding (GRAS) are to provide stratospheric and tropospheric temperature and humidity profiles that can be assimilated into NWP models.

Last Updated

27 April 2021

Published on

27 May 2020

In addition, GRAS provides navigation solutions of the Metop satellite position along its orbit.


What is GRAS?

The GRAS instrument receives high quality radio signals from GPS navigation satellites, occulting the Earth atmospheric limb, through a tangential path through the Earth's atmosphere.  As such, GRAS is not just an instrument, but requires a full system to provide products. GRAS provides a minimum of 500 atmospheric profiles per day by a process of GPS radio occultation.

GRAS product releases

spinner loading