If you've been following the news in the last six months, you may have read about the possibility of a volcanic eruption from Washington State's Mount Rainier. Though the dormant volcano has not had a significant eruption in the last 1000 years, the most recent threat assessment by the US Geological Survey, conducted in 2018, placed Mt. Rainier as the third most dangerous volcano in the US.
Photo: Jonathan E. Hendry | Simple Flying
In 2010, the eruption of Iceland's Eyjafjallajökul caused air travel all across Europe to shut down, according to the National Centre For Atmospheric Science. There are some similarities between the two mountains, but Mt. Rainier is much larger, being the third-tallest volcano in North America, according to Britannica. Thus, its eruption could be expected to affect the whole US and potentially further afield. This article will investigate exactly how and why the eruption of Mt. Rainier could be so disastrous.
What do Rainier and Eyjafjallajökul have in common?
The feature that makes Rainier so dangerous in the eyes of the US government is the same feature that allowed Eyjafjallajökul to cause so much trouble for the aviation industry in 2010; it's the water.
Photo: paigehdavis | Shutterstock
Both Mt. Rainier and Eyjafjallajökul have large amounts of glacier ice on or around them. When such ice-covered volcanoes erupt, the ice moves around due to the heat and weakening of the supporting earth. When it comes into contact with magma, which may be above 1,200 degrees Celsius (2,200 degrees Fahrenheit), according to the US Geological Survey, the explosive reaction casts ash and stone particles high into the sky, forming a cloud that can travel thousands of miles. An example is the 1980 Mount St. Helens eruption, which caused an ash cloud to travel from Washington State to central states the next day. Ash was still in the air two days later, when it was detected in the northeastern states, but particles were found to have traveled around the world after two weeks.
Related 13 Years Ago This Week: How The Eruption Of Eyjafjallajökull Brought European Aviation To A Standstill
A brief history of the severe air space closure that nearly affected the whole continent.
Posts 2
Another consequence of the high amount of glacier ice is the increased risk of lahars, mixtures of melted water, rock, and debris that can be otherwise called a mudslide. This has caused the US Geological Survey to become particularly worried, as analysis of previous eruptions at Rainier has shown lahars reaching as far as Tacoma, nearly 60 miles away. Flowing out from the mountain, they traveled up to 50 miles per hour and settled as much as a thousand feet deep. If it were to happen again, it would easily obliterate any man-made structures, becoming like quicksand when it finally stops. This would be a cataclysmic event for Washington, claiming many thousands of lives. As for Seattle-Tacoma International Airport (SEA), the data suggests that the airport may be submerged in mud and stone should Rainier erupt like it did over 1,000 years ago.
More than a minor disruption
Volcanic eruptions are not necessarily instantaneous events, and in the case of Eyjafjallajökul, volcanic activity lasted 71 days. Air travel was disrupted for two weeks, causing nearly 100,000 flights to be canceled. The Guardian reported that ash clouds cost €2.5 billion ($2.65 billion) to the aviation industry at the time. If Seattle-Tacoma International Airport (SEA) survives the eruption and the potential lahar that follows, the ash cloud overhead will make commercial flights impossible from this airport and any other whose flight path could be interrupted by the ash cloud. This could potentially cause a similar catastrophic financial hit to the aviation industry. The airport serves destinations worldwide, but most disruption would be to flights within the US, as the airport serves over 150 flights to Los Angeles International Airport (LAX), with 100-130 flights to or from nine other major cities every week.
Photo: Flightradar24 How does volcanic ash affect jet engines?
If you know anything about jet engines, you know that they suck (pun intended), that is to say, that they draw in more air than they would otherwise by traveling through the air without motorized aid. Ash particles in the air are not much of a worry when encountered at low densities. However, when large amounts are sucked in, the fine rock powder suspended in the ash is melted by the heat of the engine, becoming a layer of molten rock glass. As jet engines are full of moving parts and engineered to within fine tolerances, this can cause them to seize up and cease operating, potentially causing the plane to drop out of the sky.
A serious hazard
Volcanic ash is considered to be highly hazardous in the aviation industry, as it not only causes jet engines to cease functioning, but also impedes visibility, blocks fuel nozzles, and damages flight controls and surfaces. This means that other forms of aerial vehicles could also be affected, such as helicopters and drones. It is nothing short of a miracle that there have been no fatal incidents due to flying through volcanic ash clouds, but there have been some close calls. The Story Of British Airways Flight 9 is one such famous example. After flying through a volcanic ash cloud, all four engines ceased functioning. What followed was the longest glide performed by a non-purpose-built plane at the time, putting Flight 9 into the Guinness Book of Records.
Luckily, the crew restarted three of the four engines in time to divert and land safely, though significant damage had been done to the plane. Captain Eric Moody will certainly be remembered for his memorable line at the time:
"Ladies and gentlemen, this is your Captain speaking. We have a small problem. All four engines have stopped. We are doing our damnedest to get it under control. I trust you are not in too much distress."
Due to the dangers of volcanic ash necessitating the grounding of flights during Eyjafjallajökul's eruption, risk assessment endeavors have been ongoing since. In 2012, the International Civil Aviation Organization (ICAO) released guidance to prioritize the function of aircraft in situations when encountering volcanic ash clouds is a risk.
Related Explained: How Flying Through Volcanic Ash Poses A Dangerous Risk To Aircraft
How does volcanic ash affect an aircraft? Why can't aircraft fly through ash clouds?
Posts 1 Detecting volcanic ash clouds
The most tricky thing about volcanic ash clouds is that they are difficult to conventionally detect, being near-indistinguishable from normal clouds, both visually and on radar. Alaska is a volcanic hot spot, containing around 80% of active volcanoes in the US. As more than 25,000 airline passengers travel across it annually, detecting and tracking volcanic ash clouds is vital work. Thanks to a joint operation between NASA and the National Oceanic and Atmospheric Administration (NOAA) reported by NASA in 2020, such clouds can now be detected with near real-time accuracy. This works by satellite-tracking clouds and identifying them by their chemical composition, specifically by the Sulfur Dioxide (SO2) found in volcanic ash. It is also possible to map the clouds in 3D with this technology, determining elevation. Representing NOAA, David Schneider of the US Geological Survey said the following in 2020:
Aircraft move in excess of 500 miles per hour (805 kilometers per hour), so the faster you can get data in, process it, and have it available for analysis, the better you are."
Photo: Jesse Allen, NASA Earth Observatory How will the Seattle area fare?
If Mt. Rainier were to erupt, the aviation industry would be capable of reacting faster than in the example of Eyjafjallajökul, thanks to current technology tracking, mapping, and predicting the movement of ash clouds more accurately. It may even be that airports operating a safe distance from the ejected ash may not need to close, with safe routes potentially charted around the ash. Being so close to Mt. Rainier, however, it is doubtful that Seattle-Tacoma International Airport could continue to operate, even if a smaller eruption were to occur. Indeed, if the eruption is as destructive as forecast, evacuation may be the safest option for many in Washington state to avoid being caught in a deadly lahar. As shown below, a lahar could impact many of the surrounding communities.
Photo: US Geological Survey The Armero Tragedy
The most destructive lahar in recent history occurred when the Columbian Nevado del Ruiz volcano erupted in 1985. More than 20,000 people were killed when the mountain glaciers melted and four mudslides swept down the mountain. Mount Rainier has at least 12 more glaciers than Nevado del Ruiz, providing more water to accelerate potential mudslides, allowing them to travel further and faster. As recently as this year, CNN and Coeur d'Alene Press have reported that scientists are becoming increasingly concerned about a potential Mt. Rainer eruption, speaking of the devastation it would unleash. From examining the evidence above, this unusual combination of fire and ice will eventually cause great loss, certainly for aviation capital, but more importantly, loss of irreplaceable human lives.