A NASA-led international satellite mission headed for Blastoff from Southern California for the first time early Thursday as part of a major Earth science project to conduct a comprehensive survey of the world’s oceans, lakes and rivers.
Dubbed Swot, short for Surface Water and Ocean Topography, the advanced radar satellite is expected to give scientists an unprecedented look at the life-giving fluid that covers 70% of the planet and shed new light on the mechanisms and consequences of climate change.
A Falcon 9 rocket, owned and operated by billionaire Elon Musk’s commercial launch company SpaceX, was scheduled to lift off from the US Space Forces base in Vandenberg, about 275 km northwest of Los Angeles, before dawn on Thursday to carry Swot to the orbit.
If all goes according to plan, the SUV-sized satellite will be providing research data within a few months.
Nearly 20 years in the making, Swot includes advanced microwave radar technology that scientists say will capture high-resolution surface measurements of oceans, lakes, reservoirs and rivers in over 90% of the world.
“It’s really the first mission to observe almost all of the water on the planet’s surface,” said Ben Hamlington, a scientist at Nasa’s Jet Propulsion Laboratory (JPL) who also leads Nasa’s sea level change team.
A key focus of the mission is to study how oceans absorb atmospheric heat and carbon dioxide in a natural process that mitigates global temperatures and climate change.
Scanning the oceans from orbit, Swot is designed to accurately measure subtle differences in surface elevations around minor currents and eddies, where much of the ocean’s heat and carbon removal is thought to occur. And Swot can do it with 10x higher resolution than existing technologies, according to JPL.
It is estimated that the oceans have absorbed more than 90% of the excess heat trapped in the Earth’s atmosphere from man-made greenhouse gas emissions.
Studying the mechanism by which this happens will help climate scientists answer a key question: “What is the tipping point at which the oceans start releasing massive amounts of heat back into the atmosphere instead of absorbing it, and global warming.” accelerate rather than limit it,” said Nadya Vinogradova Shiffer, Swots program scientist at Nasa in Washington.
Swot’s ability to detect smaller surface features can also be used to study the effects of sea level rise on coastlines.
More accurate data along intertidal zones would help predict how far inland storm surges can travel, as well as the extent of saltwater intrusion into estuaries, wetlands and underground aquifers.
Repeatedly taking inventory of Earth’s water resources during Swot’s three-year mission will allow researchers to better track fluctuations in the planet’s rivers and lakes during seasonal changes and major weather events.
Tamlin Pavelsky, head of Nasa Swot freshwater science, said collecting such data is akin to “taking the pulse of the world’s water system so we can see when it’s racing and we can see when it’s slow.” .
Swot’s radar instrument operates at what is known as the Ka-band frequency of the microwave spectrum, allowing scans to penetrate cloud cover and darkness over much of the Earth. This enables scientists to map their observations accurately in two dimensions, regardless of the weather and time of day, and to cover large geographic areas much faster than before.
In comparison, previous studies of water bodies relied on data taken at specific points, such as river or ocean gauges, or from satellites, which can only track measurements along a one-dimensional line, requiring scientists to fill in data gaps through extrapolation.
“Rather than give us a range of heights, it gives us a map of heights, and that’s just a total game changer,” Pavelsky said.