Not far from Los Angeles, one of Elon Musk’s rockets is about to blast off carrying a satellite with extraordinary capabilities.
It will be used to survey nearly all the water on the surface of Earth for the very first time.
The data will provide an unprecedented depth of knowledge about the Earth’s bodies of water, including the height of oceans, rivers and lakes, and ocean functions linked to climate change.
Two experts in Australia will be front and centre, making sure the surface water and ocean topography (SWOT) satellite is sending back accurate data.
Christopher Watson, from the University of Tasmania, and the CSIRO’s Benoit Legresy say the advanced radar satellite is ground-breaking.
Designed and built at NASA’s Jet Propulsion Laboratory near Los Angeles, it will fill huge gaps in ocean monitoring by surveying the planet’s surface at least once every 21 days.
It will measure rivers, lakes, and reservoirs whose water volumes and flow rates have not been observed before and offer a view of ocean features like currents and eddies and ocean height with unprecedented clarity.
The satellite will also provide information about how the ocean is taking up atmospheric heat and carbon dioxide.
To trust the data SWOT will provide, scientists need to be sure it’s accurate.
In the early months of its orbit, during the commissioning phase, Watson and Legresy will have the job of ensuring ocean height readings made by instruments positioned in Bass Strait match what the satellite sends back.
“When the satellite flies over, we will compare what it sees with what we see,” Watson said.
“It’s such a new way of observing the ocean that we need to really compare in-situ data—data we go out in Bass Strait to collect, as with other sites dotted around the globe—to be able to check the satellite is working as we expect it.”
It has taken NASA, in collaboration with counterparts in France and Canada, about 20 years to develop the satellite, which will provide broad grid-like, two-dimensional observations, rather than linear ones over narrow tracks.
Watson remembers being a PhD candidate in 2001 and hearing about the long held desire among colleagues for high-resolution ocean sampling of the kind SWOT will deliver.
“It’s taken literally decades to get a mission like this to fly, which is really exciting,” he said.
“There’s certainly a whole lot of people around the world with their fingers crossed for this thing to launch safely and successfully, that’s for sure.”
Legresy said Australia stood to gain much from the SWOT mission.
“It will help us better understand where we are in the climate system, monitoring how the ocean around us stores the extra heat from climate change—90 percent of it goes into the oceans,” he said.
“And the majority of this goes in the southern side of the ocean.”
A Falcon 9 rocket, owned and operated by billionaire Elon Musk’s commercial launch company SpaceX, will carry the satellite into orbit.
The launch is expected to occur late on Dec. 16, Australian time, at the Vandenberg U.S. Space Force Base, northwest of Los Angeles.
