Many of Tonga’s coral reefs were still intact a year after the volcanic explosion.

Gloria Dickie

(Reuters) – Tonga, an island nation in the South Pacific still struggles with the effects of the South Pacific’s underwater volcano eruption a year ago.

Hunga Tonga Ha’apai’s shockwave sent shockwaves across the world. It produced a plume filled with water and ash which soared higher into atmosphere than any other. This triggered tsunami waves that ricocheted through the region, smashing into Fiji’s archipelago.

The coral reefs were reduced to rubble, and many fish perished or fled.

According to 2019 data from World Bank, more than 80% Tongan families depend on subsistence fishing. Tongan officials declared that they would seek $240 million to help rebuild the country, and improve food security. The World Bank donated $8 million to the relief efforts in the immediate aftermath.

Poasi Nafe, chief of the Science Division of Tonga’s Ministry of Fisheries, stated that “In terms of recovery plan… we are awaiting funds to cover expenditures associated with small-scale fishing along coastal communities.”

SILENT REEFS

Tongan territory consists largely of ocean. The exclusive economic zone that covers 700,000 km (270,271 sq miles) of water is almost 70% of the total area. Subsistence fishing, which is a mainstay of the Tongan diet, contributes only 2.3% to the nation’s economy.

In a November U.N. Food and Agricultural Organization report, they estimated that the eruption had cost Tonga $7.4 million in fisheries and aquaculture losses. This was a significant amount considering Tonga has a roughly $500 million economy. The majority of the losses were due to damage to fishing vessels. However, some commercial vessels were also damaged.

The Tongan government doesn’t keep a close eye on subsistence fishing so it is hard to predict the effect of an eruption on fish harvests.

Scientists warn that aside from the fact that some fish stocks are likely to be depleted there are other warning signs that indicate that it could take a while for fisheries recover.

According to the government’s August survey, young corals in the coast waters around the volcano site are failing to mature. Additionally, many areas that were once home to abundant and healthy reefs are now empty.

It is possible that volcanic ash has engulfed many reefs, leaving fish without food and spawning areas. Survey results showed that marine life was not found near the volcano.

The tsunami that washed over the archipelago flooded large boulder corals and created coral rubble. Although some reefs survived, the sound of foraging shrimps and fish popping and crackling, snapping, and popping noises, which were a sign that there was a healthy environment, disappeared.

Survey report: “The reefs in Tonga remained silent.”

FARMING REPRIEVE

Tongans with damaged boats and empty water have found that agriculture has been a lifesaver. Siosiua Halavatu, an soil scientist, said that despite concerns that volcanic ash would make soils too toxic for crops, “food production has resumed without any significant impacts.”

The soil tests showed that the fallout from the eruption was not dangerous to humans. Even though yam, sweet potato, and apple trees died in the eruption, their health improved once the ash had been washed away.

Halavatu stated that she supported the recovery efforts through land preparation and planting backyard gardening as well as roots crops in farms. She also mentioned that they have exported crops such as watermelon, squash, and other root crops.

He said that long-term monitoring is crucial. Tonga plans to create a national soil strategy to improve their soil testing laboratory and help farmers.

SKY WATER

Scientists are now also taking inventory of the impact of the eruption on the atmosphere. While volcanoes that erupt on land usually release ash and sulfur dioxide mostly, underwater volcanoes can release much more water.

Tonga’s eruption was no exception. The white-grayish plume reached 57 km (35.4 miles), and injected 146 million tonnes water into the atmosphere.

Water vapor can remain in the atmosphere up to a decade. This traps heat and causes more global warming. Additional atmospheric watervapor can also be a factor in the depletion of ozone, which protects our planet from UV radiation.

Paul Newman, NASA’s chief scientist for earth sciences, stated that one volcano had ten percent more global water than the rest. We are only beginning to see the effects of that.

(Reporting by Gloria Dickie from London; Additional reporting by Kirsty Neham; Editing and editing by Katy Daigle, Tomasz Jaowski