Launch of a new satellite that will monitor most of the Earth’s water | CNN

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The first mission to study almost all of the water on the Earth’s surface has been launched.

The international surface water and ocean surveying mission, known as SWOT, lifted off aboard a SpaceX Falcon 9 rocket from Vandenberg Space Force Base in California at 6:46 a.m. ET on Friday. The rocket’s first stage successfully landed on Earth at 6:54 a.m. ET.

Live coverage began on the NASA website at 6 a.m. ET.

The mission, a joint effort between NASA and the French space agency Center National d’Etudes Spatiales, will study water over more than 90% of the earth’s surface and measure the height of water in water masses. fresh as well as in the oceans. The two agencies have worked together for decades to monitor Earth’s oceans – and SWOT is the next step in their partnership.

Information from SWOT measurements will show how the oceans influence climate change as well as how global warming affects lakes, rivers and reservoirs. Satellite data can also help communities better prepare for floods and other water-related disasters, which are on the rise due to the climate crisis.

Although water is essential for the survival of life on Earth, it also shapes our weather and climate as it stores and moves carbon and heat trapped in the atmosphere by greenhouse gas emissions. Studying this resource can help scientists understand the global water balance – assessing the main sources, how these sources are changing, and the impacts this will have on different environments.

A key question scientists are asking concerns the heat exchange between Earth’s atmosphere and the global ocean, and how it might accelerate global warming.

“We’re going to be able to see things that we just couldn’t see before,” said Benjamin Hamlington, a researcher with the Sea Level and Ice Group at NASA’s Jet Propulsion Laboratory.

“We’re going to be able to follow the movement of water around the Earth between ocean and land, be able to make some of those connections, and really understand where the water is at any given time. That’s really essential because we know that with climate change the water cycle is accelerating, this means that some places have too much water, others not enough.

The satellite’s instruments will collect detailed data on freshwater and ocean features in high definition.

After years of development, SWOT’s Ka-Band Radar Interferometer, or KaRIn, is ready to fly. The instrument will be able to detect features up to 10 times smaller than those picked up by satellites at sea level.

For example, current terrestrial and satellite monitoring only collects data on a few thousand of the largest lakes in the world, while SWOT will increase this number to over a million lakes.

Researchers studying water masses have had to rely on instruments that take measurements at specific locations, such as river or ocean gauges. Similarly, previous space satellites have collected more limited data that cannot probe the true depths of Earth’s water masses. An example of a barrier to collecting accurate readings is that rivers with steep banks do not appear wider or narrower even though more water is flowing through them.

But the KaRIn radar instrument can collect measurements through cloud cover and the darkness of night. The two antennas are positioned at either end of a 33-foot-long (10-meter-long) pole on the satellite. These antennas send radar pulses to the surface of the water and receive signals back.

“For freshwater, this will be a quantum leap in knowledge,” Daniel Esteban-Fernandez, KaRIn instrument manager at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., said in a statement.

The spacecraft will see nearly all rivers wider than 330 feet (100 meters) and capture them in 3D for the first time, as well as measure ocean features less than 60 miles (100 kilometers) in diameter.

“SWOT is really going to allow us to kind of understand how the volume of water is changing in our rivers and lakes around the world,” said Tamlin Pavelsky, head of SWOT freshwater science at NASA, based in the University of North Carolina, Chapel Hill. “It’s really going to be a game-changer.”

SWOT data can help researchers fill knowledge gaps as they seek to understand the ripple effects of the climate crisis, such as how sea levels are shifting along coastlines and areas that may be more prone to flooding, to better predict rising water levels in the future.

The climate crisis is also fueling extreme weather events, including droughts and downpours. Satellite instruments can monitor both and provide critical information to disaster preparedness and water management agencies.

One place in particular that could benefit from SWOT monitoring is Alaska. Although the state sits on the edge of the Arctic Circle, it also holds about 40% of the surface water resources in the United States, including more than 12,000 rivers and hundreds of thousands of lakes. The region’s size and rugged terrain, as well as general inaccessibility, have hampered water measurements in Alaska.

“SWOT is going to allow us to see what’s happening in Alaska hydrologically in a way that we haven’t had before,” Pavelsky said.

“That’s important because Alaska, being in the Arctic, is also the place in the United States that’s going through the most climate change right now. If you want to know why that’s important, think about the number of resources we get from Alaska.

The scope of the SWOT mission means that the satellite will be able to regularly monitor other regions of the globe where water resources were previously difficult to estimate.

“It will transform our ability to deliver information that will ultimately improve the daily lives and livelihoods of almost everyone here on Earth,” Hamlington said.