Water watch

NASA's newest satellite could provide the clearest picture ever of all the water on Earth

A new satellite can monitor water level changes almost anywhere on Earth.

Originally Published: 

Orlando Sentinel/Tribune News Service/Getty Images

NASA captured public attention with two important programs this year. The James Webb Space Telescope, peering into the depths of space, and Artemis I, preparing for a trip to the Moon.

NASA/Keegan Barber

But another mission that launched at the very end of the year has its sights set on Earth — and it may be the most important launch of 2022.

Launched atop a Falcon 9 rocket on December 17, the Surface Water and Ocean Topography satellite is a joint project between NASA and CNES, France’s space agency.


miguelangelortega/Moment/Getty Images

Its mission is to observe Earth’s water — from rivers to oceans — to track the effects of climate change on water levels around the globe.

NurPhoto/NurPhoto/Getty Images

According to NASA, the data that SWOT will gather will help prepare vulnerable communities for emergencies like floods and droughts.

Climate change is creating water disruptions around the globe. Some places, like the Great Salt Lake, are facing rapidly lowering water levels due to drought.

NASA Earth Observatory

NASA Earth Observatory

Coastal communities have other problems, as rising water levels and extreme weather cause massive floods.

Before SWOT, scientists could only measure the water level of a tiny fraction of lakes around the globe. SWOT will drastically change the picture, providing measurements for 95 percent of Earth’s lakes.



SWOT’s ability to massively expand water monitoring is due to its Ka-band radar inferometer (KaRIn), a new instrument developed specifically for this mission.

KaRIn can take measurements regardless of the time of day or weather conditions and detect currents 10 times smaller than any other satellite in operation.

Roberto Machado Noa/Moment/Getty Images


Using KaRIn, SWOT will send radar pulses to the surface of the water on Earth, then receive the pulse back using two antennas to determine the water’s height.


SWOT is in orbit now, but it will take until mid-2023 for calibrations to be complete and for the satellite to start collecting data.

SWOT will carry on a more than 30-year relationship between NASA and France’s CNES, keeping an eye on water levels across 90 percent of the planet’s surface to better gauge the effects of climate change.

NASA/Keegan Barber

Thanks for reading,
head home for more!