It's common to think of glaciers as rivers of ice. The image conjured up is that of valleys full of ice. However, glaciers never form in valleys. They form on top of mountains, and ice filled valleys are but tiny outlets.
Frozen lakes
The better way to think of glaciers, if we insist of using the image of slow moving water, is that they are frozen lakes on top of mountains. Ice filled valleys are minor features.
To illustrate, we have Hardangerjøkulen, which sits on top of a 1,800 meter tall mountain in Norway. The ice is about 350 meter thick at its thickest, and it comes down to 1,050 at the sides of the mountain.
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| Hardangerjøkulen viewed from Hårteigen |
This glacier doesn't have any famous outlet. It just sits there as a giant frozen lake. It's also easily visible from afar, and therefore a good example of a glacier the way we should think of them.
The Jostedal glacier
By contrast, we have the Jostedal glacier. This glacier is more than 6 times larger than Hardangerjøkulen by extent. It sits on top of a mountain plateau that's about 2,000 meter high. It's 600 meter thick at its thickets, and its outlets go into valleys that lead the ice as far down as 350 meter above sea level.
The Jostedal glacier is more than ten times larger than Hardangerjøkulen by volume. Yet the typical image presented to us is this:
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| Outlet of the Jostedal glacier |
We get the impression that the Justedal glacier is little more than this outlet.
Deception
Making the deception even stronger is the fact that Jostedal means Joste-valley. The name of the glacier conjures up this image. However, this is but a tiny fraction of the glacier.
The lake of frozen water lies behind the mountain top in the distance, and the ice-lake is enormous. But it's rarely photographed, because it's neither visible in all its glory from the side, nor accessible to the typical hiker.
When photographed from up close, its true dimensions is lost in that there's no good reference points to compare it with. There's a lot of ice, and that's it. Satellite images are not of much help either, because they too are hard to relate to in terms of relative sizes.
This sets the stage for the deceptive notion that we're in some kind of climate crisis. The Briksdal glacier and the Nigard glacier, both outlets of the Jostedal glacier, are all but gone. It's as if all the ice is about to disappear altogether. However, as this scientific paper from 2006 tells us, the Jostedal glacier is in no danger of disappearing over the next hundred years or so.
Hardangerjøkulen
The major glacier that the scientists are worried about is Hardangerjøkulen. They think it quite plausible that this glacier, which is 350 meter thick at its thickest, will shrink in thickness by 3.5 meters every year.
Anyone with any experience of ice and how slowly it melts, will find this conclusion rather astonishing, and the scientists must themselves have been a little embarrassed with their conclusion, because they added this caveat: "Summer temperatures would have to rise by 2-3 C, without any increase in winter precipitation."
The scientists managed in this way to conclude that Hardangerjøkulen is in danger of melting away, and at the same time tell us that it's not going to happen. We're now sixteen years into their hundred year forecast, and summers are no warmer than they were when they wrote their paper. Winter precipitation is also unchanged. The conditions required to make the glacier disappear are not materializing.
Scientific caveat
The caveat that the scientists put into their conclusion is no small point. It's fundamental.
Glaciers require two things in order to form:
- Low average temperatures
- High winter precipitation
These are the conditions that exist in the west of Norway, and the reason this area of Europe has so many glaciers. There are many meters of snow falling every winter. This compacts into ice, and the glacier only shrinks if summers are warm enough to melt away as much ice as is added.
The real danger
Glaciers descend from above. They don't come crawling out of valleys. The real danger to Norway isn't what may happen if temperatures go up 2-3 C with no increase in winter precipitation, but what would happen if temperatures were to drop without any corresponding drop in precipitation. If the drop is about 1 C, we're back to the little ice age. If the drop is more than that, we might see the return of the great Scandinavian ice sheet.
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| The great Scandinavian ice sheet |
This possibility is hardly ever mentioned, and seems absurd in light of the current focus on heat waves and forest fires. However, this is what Europe looked like for most of the past 100,000 years. It's our current climate that's the anomaly. The mild temperatures and stable seasons that we take for granted are only 10,000 years old.
Fearmongering
We're told that higher temperatures will melt the great ice sheets on Greenland and Antarctica, and that this will cause sea levels to rise by 100 meter. Just about every major city will sink into the oceans. But this will require average temperatures in these places to go up much more than 2-3 C, because the average temperature on Greenland is very low, and it's even colder on Antarctica.
It doesn't matter to these ice sheets if temperatures go up by 2-3 C. What matters is how much precipitation these places get, and no-one is predicting a sharp drop. Even the most hardened climate alarmist believes that we'll see more precipitation. That means that the ice sheets aren't going to disappear. They may well grow, even if temperatures go up, because there's no direct link between temperature and the size of ice sheets. It's the combination of temperature and precipitation that matters.
Glaciers come and go
Hardangerjøkulen disappeared some 8,000 years ago, but staged a 1,000 year comeback when temperatures were at their warmest from 7,000 to 6,000 years ago. The glacier that the scientists are so concerned about was doing fine during a time when temperatures were 2-3 C above what they are today. The reason for this is that the period was unusually wet.
The idea that the ice sheets on Greenland and Antarctica will melt away over the next few hundred years is absurd. It would take thousands of years to do such a thing, and it would require much more than an increase in temperature of 2-3 C. It would also require winter precipitation in these areas to stop. That would mean no precipitation on Greenland from September to July, and no precipitation at all on most of Antarctica where winter temperatures prevail all year round.
Conclusion
We can rest assured that sea levels aren't going to rise by more than a few centimeters per decade, and that's hardly anything to lose any sleep over. Even the most unhinged climate alarmist can take comfort in this, because that's what the science that we all can agree on is saying.
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| Greta Thunberg |
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