‘Like a Shotgun’: Tongan Eruption Is Largest Ever Recorded

The eruption of the Hunga Tonga-Hunga Ha'apai volcano was so intense it reached beyond the Earth's stratosphere, into the mesosphere. (AFP)
The eruption of the Hunga Tonga-Hunga Ha'apai volcano was so intense it reached beyond the Earth's stratosphere, into the mesosphere. (AFP)
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‘Like a Shotgun’: Tongan Eruption Is Largest Ever Recorded

The eruption of the Hunga Tonga-Hunga Ha'apai volcano was so intense it reached beyond the Earth's stratosphere, into the mesosphere. (AFP)
The eruption of the Hunga Tonga-Hunga Ha'apai volcano was so intense it reached beyond the Earth's stratosphere, into the mesosphere. (AFP)

A deadly volcanic eruption near Tonga in January was the largest ever recorded with modern equipment, a New Zealand-led team of scientists revealed Monday.

The Hunga Tonga-Hunga Ha'apai volcano erupted underwater with a force equivalent to hundreds of atomic bombs, unleashing a 15-meter (50-foot) tsunami which demolished homes and killed at least three people on the Pacific island kingdom.

The natural disaster also damaged undersea communication cables, cutting Tonga off from the rest of the world for weeks and hampering efforts to help the victims.

A detailed study by New Zealand's national institute for water and atmospheric research shows the eruption blasted out almost 10 cubic kilometers of material -- equivalent to 2.6 million Olympic-sized swimming pools -- and fired debris more than 40 kilometers (25 miles) into the mesosphere, the level above the Earth's stratosphere.

"The eruption reached record heights, being the first we've ever seen to break through into the mesosphere," said marine geologist Kevin Mackay.

"It was like a shotgun blast directly into the sky."

The Hunga Tonga-Hunga Ha'apai eruption rivals the infamous Krakatoa disaster which killed tens of thousands in Indonesia in 1883 before the invention of modern measuring equipment.

"While this eruption was large -- one of the biggest since Krakatoa -- the difference here is that it's an underwater volcano and it's also part of the reason we got such big tsunami waves," Mackay added.

The team of scientists have accounted for three-quarters of the material fired out by the Tongan eruption with the rest explained as debris scattered in the atmosphere.

Mackay said the plume is estimated to have contained nearly two cubic kilometers of particles which stayed in the atmosphere for "months, causing the stunning sunsets we saw" across the Pacific region as far away as New Zealand.

His team also discovered that the volcano's crater is now 700 meters deeper than it was.

The eruption's pyroclastic flows -- deadly currents of lava, volcanic ash and gases which reach temperatures of 1,000 degrees Centigrade (1,800 degrees Fahrenheit) and speeds of 700 kilometers per hour -- carried debris from the volcano along the sea floor at least 80 kilometers away.

"But the pyroclastic flows appear to extend beyond that, perhaps as far as 100 kilometers away," said the team's principal scientist Emily Lane.

"The sheer force of the flows is astonishing -- we saw deposits in valleys beyond the volcano, meaning they had enough power to flow uphill over huge ridges and then back down again."



Blood Tests Allow 30-year Estimates of Women's Cardio Risks, New Study Says

A woman jogs in a park in Saint-Sebastien-sur-Loire near Nantes, France January 19, 2024. REUTERS/Stephane Mahe/File Photo Purchase Licensing Rights
A woman jogs in a park in Saint-Sebastien-sur-Loire near Nantes, France January 19, 2024. REUTERS/Stephane Mahe/File Photo Purchase Licensing Rights
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Blood Tests Allow 30-year Estimates of Women's Cardio Risks, New Study Says

A woman jogs in a park in Saint-Sebastien-sur-Loire near Nantes, France January 19, 2024. REUTERS/Stephane Mahe/File Photo Purchase Licensing Rights
A woman jogs in a park in Saint-Sebastien-sur-Loire near Nantes, France January 19, 2024. REUTERS/Stephane Mahe/File Photo Purchase Licensing Rights

Women’s heart disease risks and their need to start taking preventive medications should be evaluated when they are in their 30s rather than well after menopause as is now the practice, said researchers who published a study on Saturday.

Presenting the findings at the European Society of Cardiology annual meeting in London, they said the study showed for the first time that simple blood tests make it possible to estimate a woman’s risk of cardiovascular disease over the next three decades.

"This is good for patients first and foremost, but it is also important information for (manufacturers of) cholesterol lowering drugs, anti-inflammatory drugs, and lipoprotein(a)lowering drugs - the implications for therapy are broad," said study leader Dr. Paul Ridker of Brigham and Women’s Hospital in Boston, Reuters reported.

Current guidelines “suggest to physicians that women should generally not be considered for preventive therapies until their 60s and 70s. These new data... clearly demonstrate that our guidelines need to change,” Ridker said. “We must move beyond discussions of 5 or 10 year risk."

The 27,939 participants in the long-term Women’s Health Initiative study had blood tests between 1992 and 1995 for low density lipoprotein cholesterol (LDL-C or “bad cholesterol”), which are already a part of routine care.

They also had tests for high-sensitivity C-reactive protein (hsCRP) - a marker of blood vessel inflammation - and lipoprotein(a), a genetically determined type of fat.

Compared to risks in women with the lowest levels of each marker, risks for major cardiovascular events like heart attacks or strokes over the next 30 years were 36% higher in women with the highest levels of LDL-C, 70% higher in women with the highest levels of hsCRP, and 33% higher in those with the highest levels of lipoprotein(a).

Women in whom all three markers were in the highest range were 2.6 times more likely to have a major cardiovascular event and 3.7 times more likely to have a stroke over the next three decades, according to a report of the study in The New England Journal of Medicine published to coincide with the presentation at the meeting.

“The three biomarkers are fully independent of each other and tell us about different biologic issues each individual woman faces,” Ridker said.

“The therapies we might use in response to an elevation in each biomarker are markedly different, and physicians can now specifically target the individual person’s biologic problem.”

While drugs that lower LDL-C and hsCRP are widely available - including statins and certain pills for high blood pressure and heart failure - drugs that reduce lipoprotein(a) levels are still in development by companies, including Novartis , Amgen , Eli Lilly and London-based Silence Therapeutics.

In some cases, lifestyle changes such as exercising and quitting smoking can be helpful.

Most of the women in the study were white Americans, but the findings would likely “have even greater impact among Black and Hispanic women for whom there is even a higher prevalence of undetected and untreated inflammation,” Ridker said.

“This is a global problem,” he added. “We need universal screening for hsCRP ... and for lipoprotein(a), just as we already have universal screening for cholesterol.”