Mount Rainier, Washington’s snowcapped peak that stands 4.3 kilometers (2.7 miles) above sea level, has not had a significant volcanic eruption in the last 1,000 years. More than Hawaii’s exploding lava fields or Yellowstone’s vast supervolcano, Mount Rainier has many US volcanologists concerned.

“Mount Rainier keeps me awake at night because it poses a significant threat to the nearby villages. “Tacoma and South Seattle are built on 100-foot-thick (30.5-meter) ancient mudflows from Mount Rainier eruptions,” said Jess Phoenix, a volcanologist and ambassador for the Union of Concerned Scientists, on an episode of CNN’s “Violent Earth With Liv Schreiber.”

Why Mount Rainier Is The US Volcano Keeping Scientists Up At Night

The sleeping giant’s deadly potential does not stem from flaming lava flows, which, in the case of an eruption, are unlikely to spread more than a few miles beyond the boundary of Mount Rainier National Park in the Pacific Northwest. According to the US Geological Survey, most volcanic ash will likely drift downwind to the east, away from populated centers.

Instead, many scientists are concerned about a lahar, a fast-moving slurry of water and volcanic rock formed when ice or snow is rapidly melted by an eruption. Lahars gather debris as they run down valleys and drainage channels.

According to Seth Moran, a research seismologist at USGS Cascades Volcano Observatory in Vancouver, Washington, Mount Rainier’s tall height and ice and snow cover make it resilient to eruptive activity. “Hot stuff … will melt the cold stuff and a lot of water will start coming down,” he explained.

“And there are tens, if not hundreds of thousands of people who live in areas that potentially could be impacted by a large lahar, and it could happen quite quickly.”

A lahar is a rapidly flowing debris flow.
The deadliest lahar in recent memory occurred in November 1985, when Colombia’s Nevado del Ruiz volcano erupted. Just a few hours after the eruption began, a flow of mud, rocks, lava, and freezing water surged over the village of Armero, killing over 23,000 people in minutes.

In an episode of CNN’s “Violent Earth,” Bradley Pitcher, a volcanologist and Columbia University lecturer in Earth and environmental sciences, described a hardened, concrete substance that can be difficult to escape.

Pitcher stated that Mount Rainier had approximately eight times the amount of glaciers and snow Nevado del Ruiz had when it erupted. “There’s the potential to have a much more catastrophic mudflow.”

According to the US Geological Survey’s 2018 threat assessment, Hawaii’s Kīlauea volcano is the most dangerous in the US, which is unsurprising given its proximity to the population and periodic eruptions. Mount St. Helens exploded violently in May 1980 and was voted second most dangerous, followed by Mount Rainier in third.

Lahars are most commonly associated with volcanic eruptions, but landslides and earthquakes can also create them. Moran said geologists have discovered evidence that at least 11 massive lahars from Mount Rainier have reached the surrounding area, known as the Puget Lowlands, over the last 6,000 years.

Scientists have not linked the most recent of these lahars, which occurred approximately 500 years ago, to any volcanic activity. According to analysts, the flow event could have been the result of a huge landslide on the mountain’s west face.

The loose, weak rock remains in that location, and Moran and other volcanologists are particularly concerned about the possibility of a similar, spontaneous landslide-induced lahar.

Why Mount Rainier Is The US Volcano Keeping Scientists Up At Night

“We now know that the volcano can do it again. “And then we’re in this world where anything can happen at any time,” Moran explained.

“If it were the same size, it would be 10 minutes to the nearest places where people live and 60 minutes to the nearest significant settlements. “And those are very short time frames,” he added.

A 2022 study considered two worst-case scenarios. In the first scenario, a 260 million cubic meter, 4 meter deep (9.2 billion cubic feet, 13-foot deep) lahar would form on Mount Rainier’s west slope. According to Moran, the debris flow would be equivalent to 104,000 Olympic-size pools and could reach the heavily populated lowlands of Orting, Washington, roughly an hour after an eruption, moving at a rate of 13 feet (4 meters) per second.

According to the simulation, a second “pronounced hazard” area is the Nisqually River Valley, where a major lahar may displace enough water from Alder Lake to allow the 100-meter-tall (330-foot-tall) Alder Dam to spill over.

Mount Rainier’s neighbor, Mount St. Helens, farther south in the Cascade Range, erupted four decades ago, causing a disastrous lahar that did not reach any highly populated regions.

Venus Dergan and her then-boyfriend, Roald Reitan, were trapped in the Mount St. Helens lahar while on a camping vacation and are among the few persons known to have survived being swept up in a debris flow.

“I tried to cling on as we were swept downstream, but the tree bark was scraping. … During an interview for CNN’s “Violent Earth,” she recounted feeling it on her legs and arms.

“At one point, I went under the logs and dirt and accepted that this was the end. I was not going to get out of this, and I was going to die.

Why Mount Rainier Is The US Volcano Keeping Scientists Up At Night

Following the explosion of Mount St. Helens, the US Geological Survey established a lahar detection system on Mount Rainier in 1998, which has been modified and expanded since 2017.

About 20 places on the volcano’s slopes and the two paths identified as most at risk of a lahar now have broadband seismometers that send real-time data and additional sensors such as trip wires, infrasound sensors, web cameras, and GPS receivers.

Moran explained that the device is designed to identify both a lahar if the volcano erupts in the future and a lahar caused by a landslide.

Because of the constraints of 1990s technology, the original system had limited bandwidth and power requirements, resulting in data transmission every two minutes.

In March, 45,000 kids from Puyallup, Sumner-Bonney Lake, Orting, White River, and Carbonado, Washington, took part in a lahar evacuation simulation. According to the USGS, this was the first time numerous school districts exercised on the same day, making it the world’s largest lahar drill.

Approximately 13,000 pupils walked up to 3.2 kilometers (2 miles) to specified areas outside of the defined lahar zone, while the remaining schools outside the lahar zone practiced sheltering in place.

Moran stated that the fail-safe components of the Lahar detection system are roughly 45 minutes away from the next significant community; thus, that was the time window within which communities had to work.

“Most of what happens at volcanoes is close by, and that’s why you try to keep people away because things happen fast, but lahars can travel a long way from the volcano and have a big impact.”

SOURCE – (CNN)

TAMPICO, MEXICO – Tropical Storm Alberto, the season’s first named storm, weakened Thursday as it headed inland across northeast Mexico after dumping torrential rainfall in areas of the arid region and killing at least three.

The storm swiftly faded over land, and the United States National Hurricane Center reduced it to a tropical depression with maximum sustained winds of 35 mph (55 kmh). Coastal storm watches and warnings in Mexico were withdrawn as Alberto proceeded westward at 18 mph (30 kmh).

However, forecasts predicted several inches of rain were still anticipated inland in Mexico’s Tamaulipas, Nuevo Leon, and Coahuila states. South Texas was expected to experience less rain on Thursday.

Immediately after it came ashore in Tampico, there was disappointment at the lack of rain. Showers had been irregular throughout the early morning, with the sun occasionally bursting through.

Tropical Storm Alberto Weakens Over Northeast Mexico After Heavy Rains Killed 3

“We hoped it would come because water is so important here, but as far as I can tell, it went somewhere else,” said Tampico resident Marta Alicia Hernández.

The rain Tampico had hoped for could still be arriving from some of the huge system’s outer bands. Heavy rains were reported inland in the adjacent state of Nuevo Leon.

Civil protection authorities reported three deaths as a result of Alberto’s rains. They said that one guy died in the La Silla River in Monterrey, the state capital, while two kids perished from electric shocks in the municipality of Allende. According to local media, the children were riding bicycles in the rain.

Nuevo Leon Gov. Samuel García said on social media site X that Monterrey metro and public transportation services would be suspended from Wednesday night until midday Thursday when Alberto dies away.

Alberto had prompted tropical storm advisories for most of the western Gulf of Mexico’s coastline, from Texas to Veracruz. The storm landed with maximum sustained winds of 45 mph (75 km/h).

Schools in Tamaulipas state, where Alberto touched ashore, were closed through Friday. Shelters were set up across the state to accommodate residents fleeing flooding.

Tropical Storm Alberto Weakens Over Northeast Mexico After Heavy Rains Killed 3

According to the hurricane center, some portions of northeast Mexico and southern Texas could receive up to 5 inches (13 centimeters) to 10 inches (25 centimeters) of rain, with higher isolated totals likely. Some higher elevations in Mexico could experience up to 20 inches (50 cm) of rain, causing mudslides and flash flooding, particularly in the states of Tamaulipas, Coahuila, and Nuevo Leon.

Mexican authorities had minimized Alberto’s risk, instead relying on its potential to alleviate the region’s water shortage.

“The (wind) speeds are not such as to consider it a risk,” said Tamaulipas state Secretary of Hydrological Resources Raúl Quiroga Álvarez during a news conference late Wednesday. Instead, he urged people to welcome Alberto cheerfully. “This is what we’ve been waiting for for eight years in all of Tamaulipas.”

Much of Mexico has suffered from severe drought, with northern Mexico particularly heavily afflicted. Quiroga highlighted that the state’s reservoirs were depleted, and Mexico owed the United States a significant water debt for their shared usage of the Rio Grande.

“This is a win-win event for Tamaulipas,” he told reporters.

Alberto was also causing rain and floods along the Texas coast.

According to the National Weather Service, the major hazard for southern coastal Texas is flooding caused by excessive rain. On Wednesday, the NWS stated that there is “a high probability” of flash flooding in southern coastal Texas. Tornadoes and waterspouts are possible.

Tropical Storm Alberto Weakens Over Northeast Mexico After Heavy Rains Killed 3

On Wednesday, areas along the Texas coast experienced road flooding and severe rip currents, while waterspouts were reported offshore.

Octavio González, a Tampico resident, was noticeably disappointed with Alberto’s light rain.

“Very little water fell,” he explained. “We are experiencing severe drought on the south side of Tamaulipas. And the truth is, we have a lot of optimism for rain.”

SOURCE – (AP)

(CTN News) – Astronomers used X-ray data and complex supercomputer models to study the evolution of supermassive black holes over 12 billion years of cosmic history.

Scientists discovered that the black hole at the center of the Milky Way galaxy reached its four million solar masses relatively late in its lifetime.

Astronomers have struggled to understand the beginnings of supermassive black holes, which can be millions or billions of times more massive than our sun.

Astronomers Fan Zou and W. Niel Brandt, both from Penn State University, have now headed a team that has used observations and simulations to connect the two pathways of black hole formation. The results may finally provide some answers.

Zou presented their study at the 244th meeting of the American Astronomical Society in Wisconsin, raising the topic of how supermassive black holes evolve to such large sizes. “To address that, we need to track the overall growth history of these supermassive black holes.”

As previously stated, black holes grow via two basic mechanisms. The accretion of cold gas from their home galaxy is what causes one. This gas creates an accretion disc around the black hole, and stuff from it spirals towards its core.

The accretion disc can become so dense that friction between gas molecules heats it to millions of degrees, emitting X-rays. The other mechanism occurs when galaxies collide. When galaxies merge, their supermassive black holes fuse, causing a surge of gravitational waves.

The study team analyzed archival data from NASA’s Chandra X-ray Observatory, the European Space Agency’s XMM-Newton mission, and the eROSITA X-ray instrument on the joint German-Russian Spektr-RG spacecraft to determine the role of gas accretion in supermassive black hole growth.

The researchers were able to spot X-ray emissions coming from approximately 8,000 rapidly developing supermassive black holes.

“When supermassive black holes accrete the surrounding gas they emit strong X-rays, so by detecting them in the X-ray bands we can measure their accretion power,” Zou said.

Astronomers Supermassive black hole stories

They used the IllustrisTNG cosmological supercomputer simulation to model galaxy mergers throughout cosmic history. The scientists used X-ray data and simulated mergers to study the evolution of supermassive black holes across 12 billion years, from 1.8 billion years after the Big Bang to now.

These computer models “capture the overall large-scale structure [of the universe] but are also able to probe individual galaxies,” Zou stated.

According to Zou and Brandt, X-ray data reveal that accretion has been the primary driver of black hole expansion throughout cosmic history.

Furthermore, the more massive the galaxy, the faster its supermassive black hole develops through accretion. Simulations indicate mergers may impact black hole growth but are not the primary cause.

“Accretion dominates the supermassive black-hole growth in most cases, and mergers make some notable secondary contributions,” Zou stated.

These findings also indicate that supermassive black holes expanded rapidly earlier in the universe, with new ones often forming.

However, by roughly 7 billion years ago, the total number of supermassive black holes had remained rather stable, with few new ones developing. Mergers had a greater impact in later history, peaking in relevance to black-hole growth 4 billion years ago.

“We found that once the universe reaches about 40% of its age, the overall demography of supermassive black holes is very similar to the demography of supermassive black holes that we see in the local universe,” Zou stated.

Astronomers modeled our galaxy’s black hole, Sagittarius A*, and found that most of its mass formed later in cosmic time. The Milky Way’s development was primarily due to accretion, with most mergers with other galaxies occurring over 8–10 billion years ago.

The European Space Agency’s Gaia mission discovered evidence of a dwarf galaxy colliding with the Milky Way 2-3 billion years ago.

Dwarf galaxies are thought to contain intermediate-mass black holes that are tens to hundreds of thousands of times the mass of our sun, and one may combine with Sagittarius A* to increase our black hole’s mass.

Because the data only go back 1.8 billion years after the Big Bang, they don’t explain how the seeds of supermassive black holes arose. Cosmologists face a problem, as the Hubble Space Telescope and James Webb Space Telescope have discovered enormous black holes earlier in the universe.

It’s unclear how they became millions of times the mass of our sun in less than a billion years.

A study on the findings was published in March in The Astrophysical Journal, and a second paper is currently being prepared.