Juneau, Alaska Keeps Getting Flooded By Melting Glacier

A neighborhood in Juneau, Alaska inundated last week
by what is known as a "glacial outburst" flood.

 Last Tuesday, a melting glacier unleashed a torrent of water into neighborhoods in Juneau, Alaska, something that is becoming a summertime scourge in the state's capitol city. 

The water flooded about 100 homes and forced residents to flee through the frigid ice water to safety. 

If all this sounds familiar, it's because practically the same thing happened almost exactly a year later. You might remember the viral footage of a building in Juneau falling into the Mendenhall River after another flood, a type known as a glacial outburst. 

The term "glacial outburst" almost sounds like an oxymoron. Glacial evokes slowness, and outburst seems like it's something sudden. 

But follow me, here. 

The Mendenhall Glacier sits in the high elevations above Juneau. Especially in the past decade or so, a basin behind the glacier fills up with rainwater and melt from the glacier. The glacier acts like a dam to hold this lake back.

Until it doesn't

The pent up suddenly finds a way through, and the result is a flash flood in Juneau. That's what happened last Tuesday. 

Last year's version seemed more dramatic, but it only damaged or destroyed buildings right along the Mendenhall River's edge. This time, more water suddenly blasted down the hillsides than last year. That caused more widespread flooding and damaged houses further away from the river than in the 2023 event, the Washington Post reports. 

WaPo continues:

"Glacial outburst floods have poured out of Suicide Basin more than 30 times since 2011. It is challenging to predict exactly how large they will be, since conditions change each year. The jumble of icebergs in the basin keep melting - adding more liquid to the pool - and the glacier that acts as a dam keeps thinning and retreating as the atmosphere warms, so scientists don't know exactly when the pent-up water might release." 

Figuring out how much water will come out of the glacier during an outburst is hard to forecast, too. 

Scientists who are studying the glacier, and the basin - called Suicide Basin - where the water collects in the summer say year to year changes in the basin and the shape of the glacier make it difficult to determine how much water is dammed behind the glacier.

This year, the water in the basin wasn't has high as last year. But the basin is getting wider as the main glacier melts and gets thinner. The result was a greater volume of water in the basin this year that last.

This whole glacial outburst mess in Juneau - and elsewhere in the world - is of course tied to climate change. Mountain glaciers are melting all over the world, setting up similar temporary lakes behind glaciers in places like the Alps and the Himalayas. 

Those areas, too, are prone to glacial outbursts. 

 

Why Worsening Antarctic Ice Problems Are Your Problem, Too

Two new reports paint a worrying picture of Antarctic
ice, which is a problem for the whole world. 

 The amount of sea ice surrounding Antarctica reached a new low for the end of winter, increasing worries that the South Pole and surroundings are now in an ice decline similar to the Arctic at the top of the world, the Washington Post reports.

Additionally, according to another article the Washington Post, 40 percent of Antarctica's ice shelves - which are separate and different from sea ice - have dwindled in the past quarter century, and that's allowing more land ice to flow into the oceans. The extent of ice shelf melting is more extensive than previously thought. 

Yes, this stuff is oh-so-distant away from us, so you'd think who cares?  Well, everyone should. What goes on in Antarctica doesn't stay in Antarctica.

The Antarctic ice problems will probably worsen sea level rises on every coastline around the world. If you don't live anywhere near the coast, the ice crisis in Antarctica might worsen the climate changed we're all already feeling. 

SEA ICE ISSUES

 The sea ice around Antarctica usually reaches its peak in September, when winter is ending in the Southern Hemisphere and spring is beginning.

This year, the maximum sea ice extent around Antarctica this September was the lowest on record. As the Washington Post reports, the season's maximum ice extent around Antarctica was reached on September 10 - much earlier than normal, The ice was remarkably lacking. Says the Post:

"At that time, the annual ice coverage was at a record low of 6.55 million square miles - a whopping 398,000 square miles lower than the previous low set in 1986."

That's still a lot of ice.  But any decline is worrying. A lack of sea ice won't directly increase sea levels.  Ice melting on an ocean is like an ice cube melting in your gin and tonic. It won't increase the amount of liquid in your glass.

But sea ice is white. Or at least white-ish. It's great at reflecting sunlight out to space. That, in turn, helps air condition all of Earth. Open ocean is darker and absorbs sunlight, helping to warm the world.  It's called a positive feedback.

Climate change is already boosting global temperatures.Then the effects of that warming, in this case a dark surface to absorb the sun't heat, accelerates the mess even more.  

ICE SHELVES LOSING

Also, the sea ice surrounding Antarctica stabilizes the ice sheets on the continent or near its shore. The new lack of sea ice, and that darker water absorbing the sun's heat, could allow warmth to further eat away at the ice sheet,  glaciers and ice shelves

Ice shelves are enormous floating pieces of ice extending out into the ocean from glaciers on land in Antarctica. They act like dams in a way, slowing the flow of ice on the land into the oceans. Ice shelves surround most of Antarctica's coastline. 

That study I mentioned at the beginning of this post about the ice shelf decline is probably more serious than this year's crappy sea ice extent around Antarctica. 

Damage the ice shelves and you damage the ability for Antarctica to hold onto its immense glaciers.  That glacial ice flows into the oceans, melts and helps accelerate sea level rise around the world. 

Says the Washington Post: 

"'The surprising result to me was just how many ice shelves are deteriorating that substantially and continuously,' said Benjamin Davison, lead author of the study. 'Lots of ice shelves not just the big ones, are steadily losing mass over time with no sign of recovery."

The study sounds like a lot of work, but I guess most scientists are used to this. The team analyzed more than 100,000 satellite images from 1997 to 2021.   During that time, 71 of 162 ice shelves lost mass, another 29 managed to get a little bigger and the rest didn't change much one way or the other. 

West Antarctica showed the biggest ice shelve diminishment, and the numbers are huge. The Getz Ice Shelf lost 1.9 trillion tons of ice over the 14 years analyzed. Another ice shelf lost 1.3 trillion tons. 

In West Antarctica, warming ocean water is undercutting the ice shelves, prompting them to melt. The ice shelves in East Antarctica are much more stable, because the water along the immediate coast there has still managed to stay almost as cold as it ever was.

The scientists said you don't need a complete collapse of most or all of the ice shelves to cause real problems. As long as many are weakening, more land-based ice can flow into the water to melt, and raise those global sea levels. 

This is all just one more thing to worry about in the age of climate change. 

 

Even Highest Altitude European Glaciers Can't Escape This Summer's Heat

A Swiss glacier with blankets over it in a last ditch effort
to slow melting during heat waves. A new heat wave is
breaking records for the highest elevation of above
freezing air over Europe. 

 Swiss meteorologists said that Monday night, you had to reach an elevation of 17,381 feet before you encountered subfreezing air. below 32 degrees, or 0 degrees Celsius. 

That's the highest elevation on record in which above freezing air reached. 

That sounds esoteric, until you consider that Switzerland's vaunted glaciers are all below that elevation, subjecting even the highest glaciers to melting. 

According to the Associated Press:

"MeteoSwiss meteorologist Michael Schwander said it marked only the third time such readings had been tallied above 5,000 meters (16,404 feet) - and that the level was generally around 3,500 (11,483 feet) to 4,000 meters (13,123 feet) in a typical summer. 

'With a zero degree far above 5,000 meters, all glaciers in the Alps are exposed to melt - up to the highest altitudes,' said Daniel Farinotti, a glaciologist at the federal technical university in Zurich, ETHZ in an email. 'Such events are rare and detrimental to the glaciers' health, as they live from snow being accumulated at high altitudes.'

'If such conditions persist in the longer term, glaciers are set to be lost irreversibly,' he said."

Switzerland has about 1,400 glaciers, the most in Europe. They've lost at least half of their total volume since the early 1930s. They've lost 12 percent of their volume in just the past six years, the Associated Press reports.

The high elevations hot spell in Switzerland is part of an intense heat wave now hitting much of Europe. It's being caused by a "heat dome," which is intense area of oddly warm high pressure sitting over parts of the continent. A similar heat dome is afflicting the central United States with record heat. 

In France, people are being told to avoid high elevations in the Alps, because melting ice is opening new crevices in glaciers and causing rock falls. 

Four regions in France are under a rare red alert, which allows local officials to cancel outdoor events and take other measures to protect people from the dangerous heat.

The most tragic news from the European heat wave so far comes from Greece, where 18 charred bodies were found after a wildfire made possible by the record heat swept through. The dead were believed to be migrants. 

For once, we in Vermont are lucking out with the weather.  The heat in the Midwest and Plains is not forecast to spread east. Our temperatures should remain near or a little cooler than normal for at least the next week. 

Climate change, acting in concert with El Nino, has caused numerous record heat waves acros s the world since June. The month of July was the hottest on record for the world as a whole. Many climatologists expect August to be the world's hottest on record, too.

 

Glaciers Are Disappearing, Many Iconic Ones Could Be Gone Within Three Decades

Glaciers atop Mount Kilimanjero in Tanzania are among
the iconic glaciers around the world that will likely
disappear due to climate change by about 2050.

Many of the world's iconic glaciers are getting ready to disappear due to climate change, and it's very likely too late to save them even if we don't release another molecule of greenhouse gas.   

As AccuWeather reports:

"Glaciers at World Heritage sites shed around 58 billion tons of ice each year, UNESCO reports, which is equivalent to the total volume of water used annually in France and Spain combined. And these glaciers have already contributed nearly 5 percent of global sea level rise in the last 20 years."

According to the the AccuWeather report, glaciers cover around 10 percent of the world's land, which surprised me. What's supposed to happen is these glaciers can take up to 1,000 years to form. But then things get steady.  They gain mass during winter snows and cold, and lose mass in the summer as parts of them melt. 

Overall, in a perfect world, there wouldn't really be a net loss or gain of these glaciers over time. 

These glaciers will disappear whether or not effective climate change mitigation hits by 2050.

Among the glaciers expected to disappear are the last two remaining in Africa, on Mount Kenya and Mount Kilimanjaro. 

Remaining glaciers in Yellowstone and Yosemite National Parks would go poof, too. 

Other iconic glaciers that are popular with tourists in Canada, Europe, central Asia and Russia are also slated to be gone by 2050 due to climate change. 

We should worry just as much about the melting of glaciers we never heard of as much as those that are more famous. In addition to the sea level rise to which the thawing glaciers contribute, these events cause scary water problems for millions of people.

In some areas of the world, the normal summer melt from glaciers supply critical water supplies. This works only if the glaciers are fully replenished during the winter. Since that's not happening anymore, the water supply that was coming from these ice fields disappears as soon as the glacier does. 

Or, too much water melts too fast from the glaciers. That's what happened in Pakistan this past spring and summer. Part of Pakistan's problem was excessive rains from monsoons. However, another big contributing factor was the record heat during the spring.

Glaciers melted super fast, and sometimes formed temporary lakes behind obstructions like other pieces of ice or rocks.  Finally, the water pressure would get to great, and the dams made of rock and ice would suddenly collapse, causing epic flash floods downstream.

CNN reported there were 16 such incidents in Pakistan this year, compared with the five or six that would happen in each of other recent years.

No, we don't have glaciers anywhere near us Vermonters. It's still yet another climate change problem we need to pay attention to.

The Covid Pandemic Sucks To Put It Mildly. Will Climate Change Bring Us More Awful Viruses

Will climate change melt glaciers and release dangerous viruses 
from within them? Unlikely, but......

To start here, there's no evidence that the the grinding Covid-19 pandemic has anything to do with climate change.  

There's lots of ills in the world that we can attribute to climate change, but Covid isn't one of them. However, will climate change bring back zombie viruses that could be as bad or worse than Covid?

Maybe.

According to Gizmodo: 

"In the Canadian High Arctic, climate change is bringing together viruses and potential hosts in new combinations, according to recently published research. Every novel interaction increases the risk of 'viral spillover."

 If that sounds familiar, it's because one of the leading theories about Covid-19 originated from interaction between humans and some sort of bird in a live animal market. 

The last thing we need is more interaction with strange viruses.  

As Gizmodo continues:

"Viruses rely on their hosts to replicate and spread, yet most viruses are intricately co-evolved with the organisms that support them. Hosts develop defenses that viruses must work to overcome. But in instances of spillover - where a virus jumps ship to a new life form - hosts lack evolved immunity. As with the Covid-19 pandemic, when a virus finds a new host for the first time, the results can be catastrophic. "

A recent study of a high Arctic lake shows the evolutionary overlap between viruses and possible host organisms is lowest near places where glacial run-off is highest. As Gizmodo explains, that means less shared history and more opportunities for unfortunate cross-overs

Glacial ice is often thousands of years old and probably harbors ancient viruses, too. Since almost all the world's glaciers are now melting at an increasing rate, you can see where this is going. 

Before you go off on a panic about the next pandemic caused by a melting glacier, here are some things to make you relax. So far, nobody has actually seen a "cross-over" from a glacier virus to a human. Besides, most viruses out there don't even infect humans.

So the study Gizmodo cites in no, way, shape or form predicts the next pandemic. It just says that it's one more bad thing that could happen with climate change. 

There's already history that the Great Melt can create trouble in humans. For instance as The Guardian reports, a 2016 outbreak of anthrax in northern Siberia that killed a child and infected seven others was caused by a heat wave that melted permafrost that in turn exposed an infected reindeer carcass. 

Scientists have also been able to revive thousands year old viruses recovered from permafrost.  And scientists have found previously unknown viruses within Chinese and Tibetan glaciers.

So, the bottom line is climate change could start a new pandemic, but that isn't the biggest threat from climate change. It's just one more reason to try and combat it. 

 

Immense India Flash Flood Might Have Been Part Of Worrying Climate Change Hazard

Rescue workers in India after last weekend's huge flash
flood, initially blamed on a glacial lake failure. 

An extreme flash flood swept through part of the Indian state of Uttarakhand over last weekend, killing as many as 125 people and causing a swath of destruction through a mountain valley. 

According to the BBC, a wall of water and rocks poured down the valley, bursting through a dam and sweeping away pretty much everything in its path. 

News reports, at least the ones I've seen so far, don't make it clear why such a huge flood hit that part of India. However, initial speculation pointed toward something called a glacial lake outburst flood, and it's one more in a long list of dangerous effects that could easily be brought on by climate change. 

It turns out the disaster might have had another source: A huge chunk of snow fell off a mountain near Raini village, perhaps temporarily blocking a river, according to the Indian Express. 

Very heavy snow fell in the mountains on February 5 and 6, then began melting on February 7. The melting probably caused the snow to slide off the sides of the mountain, picking up water and soil along the way.

This mess, again, possibly briefly collecting behind a brief debris dam, then roared down the valley. The avalanche could have released 3 to 4 cubic meters of water into the rivers affected by the flash flood, says the Indian Express. 

If these scientists and observers are correct, this wasn't a glacial lake outburst.  However the phenomenon is still a huge threat that could cause as big or worse disasters. 

Climate change is making mountain glaciers retreat in most of the world, including the Himalayas. As the glaciers melt, the resulting water sometimes collects in a lake a little below the retreating glacier.  These lakes and potential floods also occur in the European Alps, Central Asia, South America, Iceland and other places. 

The material holding back the water is often weak and unstable.  The dam might consist of a pile of rocks and soil left behind a moving glacier. Or the dam might be a melting wall of ice that finally gives way. 

The water will finally break through the dam, maybe because of heavy rain or the splash from a chunk of ice falling off the glacier.  The hole in the dam keeps widening, so soon a torrent of water roars down a valley toward places where people are.  The wall of water picks up rocks and other material from the destroyed dam or other areas downstream, so the flash flood is full of battering rams that destroy everything in their path. 

These can happen repeatedly in the same area.  The dam that was breached by the glacial lake can re-form, then collapse again.  

There has not been an apparent, real increase in these floods due to climate change, but scientists do worry this will become an increasing problem in areas with mountain glaciers as the world continues to warm. 

Ominously, glacial lakes are growing and becoming more numerous in the Himalayas as glaciers melt, so you can see how this is going to be issue to be reckoned with in future generations.