The eruptions occur in the volcano's crater, a feature named Brimstone Pit, at 1,837 feet (560 meters) below sea level.
The volcano has been going through nearly constant low-level eruptions since at least 2004, when it was first observed, Embley says. It could potentially keep erupting for decades, giving scientists the opportunity to monitor its growth.
While the eruptions would be strong enough to send scientists running for cover on land, the pressure of water at Brimstone Pit dampens the explosive power, Embley explains, allowing scientists get up close with their cameras.
To date, the team has filmed billowing yellow plumes, droplets of molten sulfur, spewing rocks, landslides, a mysterious layer of cloudy water midway up the volcano, and red lava growing in the crater.
In addition, the scientists have observed communities of microscopic bacteria and two species of shrimp living at the volcano.
The bacteria settle around vents that spew out hydrogen sulfide, a chemical that the life-forms convert into food, says Verena Tunnicliffe, a marine biologist at the University of Victoria in British Columbia, Canada.
"So that means there's an OK food source sitting there if you're able to live in an unstable, nasty place," she said.
"That's where the shrimp come in," Tunnicliffe added.
The juveniles of both shrimp species graze on the bacteria, which look like little hairs on rocks and other volcanic debris. One of the shrimp species' claws is shaped like tiny garden shears, Tunnicliffe says.
The adults of the other shrimp species eventually grow larger front claws and turn into carnivores. When Tunnicliffe first saw the second species in 2004, she thought the animals were there by some sort of accident. She didn't see much meat in the environment.
So she was surprised to see them in abundance again this year.
"At first we couldn't figure out what they were doing until a bunch swam by holding dead animals under their legs," she said.
The shrimp eat fish, other shrimp, and squid that are killed by the noxious volcanic gasses and then sink to the base of the volcano.
"These bottom shrimp are the garbage collectors of the deep," she said.
In future studies Tunnicliffe hopes to tease out what allows these shrimp to survive in an environment that is inhospitable to just about everything else.
"What are they doing that's different?" she said.
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