Geoengineering polar glaciers to slow sea-level rise

Wolovick: Geoengineering polar glaciers to slow sea-level rise
Princeton climate researcher Michael Wolovick argues in a Nature Comment that targeted approaches could prevent glaciers from melting, thereby forestalling some of the most expensive effects of global climate change. Ice sheets that spread from continental shelves to the ocean are highly vulnerable to melting near the grounding line, which is the point at which they lift off of the bedrock and start floating on the ocean (purple). Wolovick proposes building an artificial sill -- an underwater wall 3 miles long and 350 feet high -- to block warm water (red) from reaching the glacier. Credit: Michael Wolovick, Princeton University

Targeted geoengineering to preserve continental ice sheets deserves serious research and investment, argues an international team of researchers in a Comment published March 14 in the journal Nature. Without intervention, by 2100 most large coastal cities will face sea levels that are more than three feet higher than they are currently.

Previous discussions of geoengineering have looked at global projects, like seeding the atmosphere with particles to reflect more sunlight. That's what makes this focused approach more feasible, says Michael Wolovick, a postdoctoral research associate in Atmospheric and Oceanic Sciences at Princeton University and a co-author on the Comment. (Nature editors commission Comments, short articles by one or more experts that call for action and lay out detailed solutions for current problems.)

"Geoengineering interventions can be targeted at specific negative consequences of , rather than at the entire planet," Wolovick said.

The ice sheets of Greenland and Antarctica will contribute more to sea-level rise this century than any other source, so stalling the fastest flows of ice into the oceans would buy us a few centuries to deal with climate change and protect coasts, say the authors.

"There is going to be some sea-level rise in the 21st century, but most models say that the ice sheets won't begin collapsing in earnest until the 22nd or 23rd centuries," said Wolovick. "I believe that what happens in the 22nd or 23rd centuries matters. I want our species and our civilization to last as long as possible, and that means that we need to make plans for the long term."

Wolovick started investigating geoengineering approaches when he realized how disproportionate the scale was between the origin of the problem at the poles and its global impact: "For example, many of the most important outlet glaciers in Greenland are about 5 kilometers (3 miles) wide, and there are bridges that are longer than [that]. The important ice streams in Antarctica are wider, tens of kilometers up to 100 kilometers, but their societal consequences are larger as well, because they could potentially trigger a runaway marine ice collapse. The fast-flowing parts of the ice sheets—the outlet glaciers and ice streams—might be the highest-leverage points in the whole climate system."

The glaciers could be slowed in three ways: warm ocean waters could be prevented from reaching their bases and accelerating melting; the ice shelves where they start to float could be buttressed by building artificial islands in the sea; and the glacier beds could be dried by draining or freezing the thin film of water they slide on.

The engineering costs and scales of these projects are comparable with today's large civil engineering projects, but with extra challenges due to the remote and harsh polar environment. Engineers have already constructed artificial islands and drained water beneath a glacier in Norway to feed a hydropower plant. Raising a berm in front of the fastest-flowing glacier in Greenland—constructing an underwater wall 3 miles long and 350 feet high in arctic waters—would be a comparable challenge.

Such a project would easily run into the billions of dollars, but the scientists note that without coastal protection, the global cost of damages could reach $50 trillion a year. In the absence of geoengineering, the sea walls and flood defenses necessary to prevent those damages would cost tens of billions of dollars a year to build and maintain.

The researchers note that potential risks, especially to local ecosystems, need careful fieldwork and computer modeling, and the glaciers and their outflow channels need to be more precisely mapped and modeled.

Most importantly, this approach would address a symptom, not the cause. "Glacial geoengineering is not a substitute for emissions reductions," Wolovick said. His approaches could forestall one of the bigger causes of global sea-level rise, but they will not mitigate global warming from greenhouse gases.

The fate of the ice sheets will depend ultimately on how quickly the world brings down fossil fuel emissions.

"Glacial geoengineering will not be able to save the ice sheets in the long run if the climate continues to warm," Wolovick said. "In the long run, there are two possible routes that glacial geoengineering could take: on the one hand, it could be a stopgap solution meant to preserve the ice sheets until the climate cools enough that they are once again viable on their own; on the other hand, it could be a managed collapse meant to keep the rate of sea-level rise down while slowly letting the waste away. If we emit too much carbon into the atmosphere, then the only viable long-term usage of glacial would be to orchestrate a managed collapse."

Wolovick argues against defeatist attitudes. "Climate change is not an inevitable apocalypse, climate change is a set of solvable problems," he said. "Climate change is a challenge that our species can and will rise to meet."

"Geoengineer polar glaciers to slow " by John Moore, Rupert Gladstone, Thomas Zwinger and Michael Wolovick appeared in Nature on March 14. Wolovick's research was supported by a departmental postdoctoral fellowship that is funded by the National Oceanic and Atmospheric Administration.


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Glacial geoengineering—the key to slowing sea level rise?

More information: John C. Moore et al, Geoengineer polar glaciers to slow sea-level rise, Nature (2018). DOI: 10.1038/d41586-018-03036-4
Journal information: Nature

Citation: Geoengineering polar glaciers to slow sea-level rise (2018, March 19) retrieved 16 October 2019 from https://phys.org/news/2018-03-geoengineering-polar-glaciers-sea-level.html
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Mar 19, 2018
Who comes up with these ideas? This is a great evil you are contemplating.

Mar 19, 2018
Geo engineering with respect to "Climate Change" is without merit.

Mar 20, 2018
Who comes up with these ideas?

People who have both a lot more morality (in the form of compassion for future generations) and a lot more intelligence.
To do nothing here is evil.
Ideas and thinking is exactly what is needed here.

Mar 20, 2018
Geo engineering with respect to "Climate Change" is without merit.

No, its serious consideration is with merit.

Mar 20, 2018
God save us!
The astonishingly stupid of the AGW Cult, blindly driven by their ignorance and dogma, again proposes a "solution", to a non-problem, which will absolutely F things up.
Remember, these are the same A-holes who decided that bio-fuels from food crops was a great idea and solution.

Mar 20, 2018
antigoracle

Your insane delusional ranting and ravings convinces nobody here other than those that are already too far gone like yourself.
I listen to what the science says over your delusional ranting and ravings any day.
You don't even present an argument let alone evidence to counter the scientific evidence and the proven scientific facts you cannot tolerate.
All you present is hateful insults and straw mans, not rational argument.

In my next post, I present the evidence you hate so much;

Mar 20, 2018
https://skeptical...ming.htm
"...
The laws of physics tell us that without the atmosphere, the Earth would be approximately 33°C (59.4°F) cooler than it actually is.
...
One way of measuring the effect of CO2 is by using satellites to compare how much energy is arriving from the sun, and how much is leaving the Earth. What scientists have seen over the last few decades is a gradual decrease in the amount of energy being re-radiated back into space. In the same period, the amount of energy arriving from the sun has not changed very much at all.
...
The final piece of evidence is 'the smoking gun', the proof that CO2 is causing the increases in temperature. CO2 traps energy at very specific wavelengths, while other greenhouse gases trap different wavelengths. ...
(...see graph on link...)
(and, as the graph shows;)...most of the energy being trapped in the atmosphere corresponds exactly to the wavelength of energy captured by CO2.

Mar 20, 2018
just to pile it on, yet more evidence;

https://cobybeck....hat-co2/

Mar 20, 2018
The Greenland glaciers are heated from the bottom by geovolcanism

So what? How is that evidence against a warmer climate being able to melt glaciers?
Nobody denies the existence of volcanism but volcanism isn't the only possible source of heat in nature because there are also other sources.

Mar 20, 2018
@Mackita,
Why did you include that link to the Greenland ice sheet?? The article says nothing whatsoever about geovolcanism, or molten bedrock (lol).

Mar 20, 2018
The moron climate "scientists" cannot even accurately quantify the Sun-Earth connection, all their models are based upon the erroneous guesses put forth by the astrophysicist plasma ignoramuses. Needless to say, this moronic "plan" to solve a problem that does not exist will only cause numerous unintended consequences and exasperate the situation.
Chicken Littles like dumy need to go take a flying leap off of the nearest high point and spare us from your nonsense.

Mar 20, 2018
.......astrophysicist plasma ignoramuses]


I expect they know what a collisionless plasma is though. You don't, so shut up.

Mar 20, 2018
CO2 is produced by oxidization of methane which is released by global warming. The other likely candidate (geothermal) origin was not even tested

So are you implying that all the resent climate warming over the last few decades must be due to "oxidization of methane" and "geothermal" and not just a small part of it?
If so, you have absolutely no evidence for this.
Meanwhile, science tells us a different story with scientists, contrary to your false assertions that give no credit to their actual intelligence which is more than yours, take into account ALL known sources of heat etc known to be non-negligible.


Mar 20, 2018
@Jonesdave: which link do have on mind? I linked four studies (1, 2, 3, 4)


1,2,3 & 4. None of them mention volcanism, and none of them mention molten bedrock. We are probably talking about an ancient mantle plume. It will provide some heat, but nothing like a volcano!
As the chap in your link #3 says:

It is a combination of higher temperatures in the air and the sea, precipitation from above, local dynamics of the ice sheet and heat loss from the Earth's interior that determines the mass loss from the Greenland ice sheet," Rysgaard explained.

Mar 20, 2018
Geo engineering with no backup plan strike again!

Michael Wolovick is intending to change the climate for people in 200 to 300 years in the future to save humanity with no backup plan to reverse his engineering when it goes wrong. The most ignoramus aspect of this idea is he won't be around to witness the calamitous events when it all goes terribly wrong!

Mar 20, 2018
The one saving grace Michael Wolovick balmy idea, is the cost! It will cost billions of dollars a year for 200 to 300 years to maintain.

Mar 20, 2018
Continental ice sheets
continental ice sheets imply land covered by ice, the ice mass pressure melts a layer of ice at the land ice interface allowing the ice to flow and liquid ice melt water underground water to flow in the forming ice caverns the weight of the ice deformates the earth's crust causing sediment plastic flow further melting the ice and crust movement.

Mar 20, 2018
CO2 is produced by oxidization of methane which is released by global warming. The other likely candidate (geothermal) origin was not even tested

So are you implying that all the resent climate warming over the last few decades must be due to "oxidization of methane" and "geothermal" and not just a small part of it?


Yes he is and has been for a while. It's utter bunkum of the unicorns variety. So damn tired of it, frankly.

Mar 20, 2018
It will provide some heat, but nothing like a volcano!
It actually once happened at the https://www.natur...01273-1. Geolvolcanic activity also accounts geysers.


Liar. Please show me where any of that stuff you linked talks about volcanism or molten bedrock. Idiot. Stop lying. Yes? Getting sick of knobs like you. IQ of a trilobite, but think you can dictate to other people? Yes? Trust me; you are well found out.

Mar 21, 2018
volcanism isn't the only possible source of heat in nature because there are also other sources
Of course they are - the question is, which is dominant for climatic changes.

No, the question is what has volcanism got to do with the recent man made warming of climate in the lat few decades. The answer is, absolutely nothing.

Mar 21, 2018
It all melted during few thousands years and the origin of it was geothermal.


No, it wasn't.

Mar 21, 2018
the question is what has volcanism got to do with the recent man made warming of climate in the lat few decades. The answer is, absolutely nothing.
This is just a hypothesis to be tested.

No, it clearly isn't. Because volcanism cannot possibly begin explain the recent global climate warming in the last few decades and only a moron like yourself would claim otherwise.
HOW can volcanism explain a significant part the recent warming let alone most of it? Has there been a recent dramatic increase in global volcanism in the last few decades to explain it? Of course not. Thus that is no more than a "hypothesis to be tested" than the stupid 'Goddidit' hypothesis is a "hypothesis to be tested"; neither explains anything. True science doesn't deal with non-starter hypothesis.

Mar 21, 2018
No, it wasn't.
I linked the https://www.natur...1273-1.. .

What has your link got to do with your moronic claim that volcanism can explain the recent global climate warming in the last few decades?
You link doesn't say anything to support your moronic claim and I challenge you to quote directly from your link where it says otherwise...
Your link title is
"Enhanced ice sheet melting driven by volcanic eruptions during the last deglaciation"
Well, the last deglaciation happened a very long time ago so that cannot explain the recent global climate warming in the last few decades.
Nothing in your link supports your moronic claims.

Mar 21, 2018
HOW can volcanism explain a significant part the recent warming let alone most of it?
I already explained it: it released the methane from soil and marine bottom, .

That is a process that cannot possibly explain most of the recent global climate warming in the last few decades and your link doesn't make such a claim and I challenge you to show any link that supports the contrary...

Mar 21, 2018
In my hypothesis the source of heat also isn't volcanic only - but geothermal one,.

Your hypothesis, with or without the "geothermal" part, cannot explain the recent global climate warming in the last few decades and, as a hypothesis for that recent warming, is totally unsupported by the empirical evidence which points to man made causes being the most likely dominate cause of the recent global climate warming in the last few decades.
I go with the empirical evidence and what the science says and what the credible scientists say, that know things about it you and I don't, over your idiotic theories any day.

Mar 21, 2018
That is a process that cannot possibly explain most of the recent global climate warming in the last few decades
it's byproduct of geothermal warming. ..

No, it clearly isn't. Science and the evidence shows for the most recent warming it has nothing to do with 'geothermal'.
As implied by even your own links, there is NO evidence of any significant increase in geothermal activity in the last few decades let alone it being responsible for the recent global climate warming thus your 'hypothesis' is completely baseless and idiotic.
Why would geothermal activity that has not increased be responsible for warming NOW rather than at some other time in the past? -you make no sense.
In contrast, as shown by the links I already given you that says what the science says, there is good evidence that man made CO2 is almost certainly the main culprit.

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