The $4M new ocean simulator by UCSD could help to solve one of the most difficult mysteries in climate change.

The new $4-million ocean and atmosphere simulator at UC San Diego’s Scripps Institution of Oceanography is like a giant aquarium — minus the fish but capable of growing a microscopic jungle of marine organisms.

It measures in at 120 feet in length, 18 feet high, and can hold 36,000 gallons water.

Researchers hope the first-of-its kind machine will help solve, among other things, one of science’s most pressing questions: Will clouds help slow or speed up global warming?

Kimberly Prather, an atmospheric chemist at Scripps, called it the “largest single uncertainty in all of climate change.”

“There’s not a model right now that can actually predict where and when clouds form,” said Prather, the director of the Center for Aerosol Impacts on Chemistry of the Environment at Scripps.

Scientists believe that clouds reflect sunlight and have a cooling effect on the planet. However, they can trap heat, particularly high-flying, wispy clouds.

That means, depending on how clouds react to rising accumulations of greenhouse gas, Earth may have a built-in buffer against climate change — or be headed for runaway warming.

Specifically, Prather and other researchers plan to use UCSD’s new facility to study the conditions that form clouds over the ocean. These white puffs of moisture form when water droplets adhere to tiny marine aerosols like phytoplankton, salts, and even viruses.

Researchers have studied these interactions in seawater, which is difficult to control. Prather believes the world could soon experience a major scientific breakthrough with the simulator.

“People are talking about using the ocean potentially for geoengineering, making more clouds to keep the Earth cooler,” she said, “but nobody understands quite what comes out of the ocean.”

‘We need to go big’

Grant Deane, Scripps research oceanographer, and Dale Stokes led the development of the new facility in La Jolla. It was called the Scripps Ocean Atmosphere Research Simulator or SOARS.

The scientists were replacing an older ocean simulator that was built in the 1960s. There are many other similar facilities all around the globe.

“We looked at each other and went, ‘We need to go big,’” Deane said. “If we want to understand the consequences of burning fossil fuels, we have to understand how the ocean and the atmosphere mix.”

The National Science Foundation granted the university a $2.8 million grant to build the new facility in 2017. This was a major win for the team. The idea: Researchers can study the interactions between wind, waves, and microbial marine life with unprecedented accuracy. UCSD paid the remainder of the cash, which included an additional $3 million for renovations to the building housing the facility.

SOARS is similar to its predecessor. It has a wave channel, wind tunnel, and can generate waves up to four feet high and winds up to 60 miles an hour. However, the simulator sets itself apart with an ability to filter the air and water, while also growing specific marine organisms using skylights known as “solar tubes.”

Deane stated that the concept for the ocean simulator was a collaboration of multiple disciplines and researchers. The facility’s solar tubes, for example, were included based on input from Scripps microbiologists Farooq Azam. Ken Melville, the late physical oceanographer played a significant role.

“That was the genesis for this machine,” Deane said. “It’s a complex mixture of oceanography, biology and chemistry.”

Dale Stokes, Scripps Institution of Oceanography researcher, was seen in an observation area of the Scripps Ocean Atmosphere Simulation Simulator on November 17, 2021.

(Nelvin Cepeda/The San Diego Union Tribune)

SOARS’ temperature controls can accurately replicate tropical and Arctic conditions. Stokes explained that this extends to the main observation area to prevent the window to the wave channel’s fogging up.

“When this is in polar mode, you’re in here wearing a jacket,” he said. “We’ll have a rack of parkas outside.”

The facility’s monitoring equipment will include lasers and cameras to feed data into a central desktop computer. Scientists can also place probes and other instruments directly into the water by drilling through a long, narrow section of replaceable plexiglass on the channel’s tank.

“All the individual components have been worked out before, just never all brought together,” Stokes said.

There are many options for research

Drew Lucas, a professor from UCSD, brought a class of undergraduates studying oceanic science and atmospheric science to the simulator. He explained that the facility will be used by researchers at the highest levels, but also by students studying basic scientific concepts.

“You can go to the beach, but with this, you can do a controlled experiment,” he said. “It homes in on what the physics really are.”

Lucas hopes to also use the simulator to conduct his own research on seagoing robotics that could use ocean currents for propulsion.

“A big push is to figure out how to harvest energy from the environment to power vehicles,” he said. “A good example is a solar cell on a buoy or wave power.”

Prather has other plans for SOARS. Prather wants to use the facility for research on the transmission of diseases via ocean spray.

On Wednesday, Nov. 17, 2021, Scripps Institution of Oceanography researcher Grant Deane (C) speaks with undergraduate students about UCSD’s new ocean and atmosphere simulator.

(Nelvin Cepeda/The San Diego Union Tribune)

She’s taken a particular interest in the impacts of sewage-tainted runoff from Tijuana that routinely fouls shorelines in Imperial Beach. Bacteria and viruses could be “aerosolized in the surf zone,” she explained.

“People that live in Imperial Beach have serious respiratory issues, especially after it rains, when you think things would be cleaner,” said Prather, who’s formed relationships with local clinicians. “If you pump raw sewage in the ocean, some portion of that is going to come back out.”

Ideally, SOARS will be a focal point for a wide variety of “interdisciplinary campaigns,” Deane said, such as looking at issues around sea-level rise or the air-quality impacts of algae blooms.

“We’ll get eminent scientists and early career scientists,” he said. “We’ll get a broad range of people coming together and talking together, working together.”

What are the missing models?

Recently, scientists in the science of clouds and climate change made a significant breakthrough with a research paperThis summer, the journal Proceedings of the National Academy of Sciences published the paper.

Researchers from the Imperial College London found that it’s “very likely” that climate change’s impact on clouds will lead to more warming, not less.

Climate modelers are still uncertain about the cloud-feedback effect, also known as the “cloud-feedback effect”. Researchers have more confidence that current models are on track after a recent analysis involving global satellite observations.

“What we found is kind of middle of the road,” said Paulo Ceppi, the study’s lead author and climate scientist at Imperial College London. “It’s neither the case that clouds will strongly buffer global warming or lead to extremely fast warming. It’s moderately amplifying the effects of global warming.”

However, research efforts, such as those using UCSD’s new simulator, could turn up a wildcard, Ceppi said.

“If the biology in the ocean changes with warming, it could be something that all the models are missing,” he said. “I think that’s a concern. That’s a real problem, so it’s great that these people are investigating this.”

Prather has requested the simulator to be used for experiments beginning in June. The experiments will examine the effect of sea-spray aerosols and gases coming out of the ocean at high speeds on the formation of marine cloud formations. Testing on the facility will continue through early next year to ensure it’s properly calibrated.

Scientists from outside UCSD may also be able to gain hands-on experience using SOARS. Tim Bertram is a professor of chemistry at the University of Wisconsin-Madison.

“To look at the ocean atmosphere is in some regards uncharted territory,” he said. “It can open doors to answer and probably even ask new questions.”