Tonga's eruption could damage the environment for years to come, scientists warn

Scientists have warned, using satellite images, that Tonga’s massive volcanic eruption on Saturday may threaten the environment, coral reefs, erode coastlines, and disrupt fisheries for decades to come.

Hunga Tonga-Hunga Ha’apai, an undersea volcano that erupted on January 15 and prompted tsunami warnings throughout the Pacific, has released sulfur dioxide and nitrogen oxide into the atmosphere, two potentially harmful gasses that produce acid rain when they interact with water and oxygen.

“There is likely to be acid rain around Tonga for a while to come,” according to Shane Cronin, a volcanologist at the University of Auckland, in a statement to Reuters.

There is widespread crop damage caused by acid rain, including damage to Tongan staples like taro, corn, bananas, and garden vegetables. “Depending on how long the eruptions last, food security could be compromised,” Cronin said.

Damage to Marine life

A significant amount of ash falling on coral reefs could lead to catastrophic damage, which was already at risk before the eruption.

“Vast areas of the reefs in the immediate impact area at Hunga Tonga are probably buried and smothered by large deposits of volcanic ash,” said Tom Schils, a marine biologist at the University of Guam.

Schils told Reuters that volcanic eruptions such as the one on Saturday release more iron into the water, which promotes the growth of blue-green algae and sponges that further degrade the reef.

While scientists have yet to investigate the situation on the ground, satellite imagery shows ash blanketing the ground. Ashes can harm marine life in the ocean, according to Tonga Geological Services, which warns that nearby seawater is contaminated by toxic volcanic discharges, and fishermen should “assume fish in these waters are poisoned or poisonous”.

There are 170 islands in Tonga, of which 36 are inhabited and are home to about 100,000 people.

The majority of Tongans rely on the ocean for food and livelihood, so scientists have expressed concern about fish migrating or perishing due to the eruption.

“It will be a while before the same or new fishing grounds will be restored,” Marco Brenna, a geologist at the University of Otago in New Zealand, said.

Tsunami waves

A tsunami wave of about 4 feet was recorded by a Tongan sea-level gauge after the eruption. As a result of tsunamis, shorelines are eroded rapidly, resulting in the destruction of coral reefs and the inability to cope with rising seas and storm surges.

A storm buffer in Tonga consists of coral reefs, seagrasses, and mangroves along the coast, valued at about $11 million annually. Before the COVID-19 pandemic, the tourism industry has brought in $5 million annually to the Island.

Peru oil spill

A massive tsunami produced by the eruption is also believed to have caused an oil spill at the Pampilla Refinery in Peru, owned by the Spanish company Repsol.

Authorities in Peru sealed off three beaches after a “limited spill” of oil occurred near the capital, Lima, on Monday.

Mr. Ruben Ramirez, the state’s environment minister, said the accident was a 3km stretch along the beaches.

“There is great damage to biodiversity, and it could even impact human health,” Ramirez said. “And so it has been ordered that the area be cut off for all kinds of activity.”

It was reported that the spill, which occurred during off-loading from a tanker, had been controlled by the National Emergency Operations Center.

According to AFP news agency, local Ventanilla resident Brenda Ramos says the community remains concerned.

“This affects the fishermen, the population that they feed with the fish, and marine animals,” Ramos said.