Monday, March 19, 2018

Sounds More Like Glacial Geo-Adaptation to Me

 (Source)

Interesting article in Nature speculating that certain possibly feasible, artificial interventions in major ice flows from Antarctica and Greenland could slow the pace of sea level rise. The ideas are artifical barriers that slow the flow of "warm" ocean waters that undercut and speed up ice flows, creating artificial islands that partially pin ice floating sheets in place, allowing them to brake ice flows from land, and pumping out lubricating water flows from underneath ice sheets that speed up their flow.

The authors acknowledge the difficulties and potential environmental damage caused by these interventions and consider them no substitute for reversing GHG emissions. To the extent that the effort is to reduce ice flow velocities to speeds closer to what happened prior to climate change, it sounds to me like it's approximating a more natural system than doing nothing. That's why I'd consider it more of an adaptation approach than a geoengineering approach that is meant to subsitute for actions on GHG emissions.

I'd be interested to know if these adaptations can help stabilize and recover the ice sheets that in the long term seem doomed, even with some level of recovery from climate change.

Definitely seems worth further research.




19 comments:

Henosis Sage said...

"Definitely seems worth further research."

Oh dear me.

Prof. Philip Mirowski
https://www.youtube.com/watch?v=I7ewn29w-9I&feature=youtu.be&t=33m40s

Fernando Leanme said...

I dont see why you have such a mental block about Geoengineering. As far as i can see it's better to study several approaches, and eventually pilot two or three. Putting iron in the ocean near coast lines, in higher latitudes during spring time, sure seems like an approach which merits study.

Barton Paul Levenson said...

FL: I dont see why you have such a mental block ...

BPL: Any post which starts out like this is antagonistic and shows the poster has an axe to grind.

Brian Schmidt said...

Fernando - I think geoengineering is an admission of weakness, that we're not doing the obviously right thing soon enough and have to consider dangerous additional methods.

I also think we should research it, because that admission of weakness may be an accurate statement.

So no, no mental block.

Russell Seitz said...

Brian hails from ground zero of one of the largest ongoing SRM experiments - LA is a big player in the Cool Cities Initive, which aims to cool the megapolis by increasing its albedo with white roofs and paler paving.

As to cutting the seawater heat flux that's accelerating polar climate change and sea level rise by chewing on the Greenland glaciers and arctic sea Ice, he should read what Moore et al are presently reading , like this paper from ClimaticChange

Canman said...

"... that we're not doing the obviously right thing soon enough... "

I don't think that anything is an "obvious right thing". Cutting enough greenhouse gases looks utterly futile to me, but even if it's not, geoengineering might still be preferable.

If Edward Teller were still alive, perhaps he could stop the ice sheets with H-bombs.

William Connolley said...

This seems a bit wacky. Moore et al. have done the most basic research by comparing their proposed cubic-metres to something else, but their engineering feasibility seems to end there. It feels like something that should be talked about, just to make sure you haven't forgotten any obvious possibilities, but doesn't look like one of the obvious possibilities.

Fernando Leanme said...

William, sometime in my previous life I coauthored a paper on arctic port construction. At the time I was leading a small team, and was also the dynamic model code writer (we used the model to test port design functionality, meaning we tested the ability of ships to come into port and unload/load cargoes in X,Y weather). So even though my specialty wasn't the ice loads on fixed structures, berms, ships, etc, I did learn that ice loads are better modeled as if the ice were something similar to a vibrating steel cylinder (it definitely isn't modeled like water!).

My impression is that any solid object put in front of a large ice mass such as a giant iceberg will simply get wiped out. Drilling wells and pumping water sounds impractical for several reasons. One would be the enormous logistics challenge involved in keeping a pump system running on ice in very cold weather, airlifting the fuel, and keeping the operators and maintenance personnel alive.

Another reason would be the limits on fluid flow within a boundary layer made of very fine grained crushed rock. The way I understand it, the ice mass "slides" on smooth rock lubricated by a paste of ground rock and water. If we place a well in that environment it will be difficult to have it drain this mush very far from the well, because as we drain the system we create a closure force (the ice simply expands a bit and bites into the underlying rock). Evidently the locked section will be dragged along by the surrounding ice field which won't be locked because the fluidized layer won't be drained. To get around this problem we can envision drilling hundreds of wells each of which drains a small volume, thus creating a large contact area. I imagine this locked down sector will eventually release and move a couple of meters, causing a small quake. So the system has to include several hundred wells with central power distribution nodes which in turn are connected to a set of generators kept in a suitable housing or enclosure. Thus these two items could make the venture quite expensive.

Entropic man said...

Fernando Leanne

Geoengineering projects do seem to be expensive. A recent proposal to lower sea level by pumping water from the oceans onto the Antarctis ice sheet was costed at 12 trillion dollars per mmm of sea level reduction.

Canman said...

The thing about meteorology and climate science that most surprised me was how little cloud formation was understood. I recently read in Oliver Morton's The Planet Remade, that cloud seeding has not been very reliable. Perhaps, if clouds were better understood, seeding techniques could be perfected and some of the dreaded increased water vapor could be redirected to snow cover in higher latitudes.

Barton Paul Levenson said...

I wonder if pumping out the base water could be combined with shipping that water to drought-stricken countries?

Canman said...

Assuming that those flowing ice sheets are fresh water, perhaps they could be cut up into barges and tugged to drought stricken countries. Maybe the tugs could be electric, powered by solar panels that shade the ice. Before there was mechanized refrigeration, there was supposedly a thriving business of shipping ice from Arctic regions to people who wanted ice cubes for their drinks.

David B Benson said...

Ha, ha, ha.

Gasp. Chortle.

EliRabett said...

It's been proposed. Even SF novels writtern about it. There are issues

Canman said...

DBB, if you're laughing at me, I don't think ice barges are any more outlandish than Mark Jacobson's proposed 387 CSPs for the sunny state of New York.

Tom said...

Jerry Pournelle used the idea in short stories, maybe a novel and in his science popularization effort 'A Step Further Out' in 1978 (?).

David B Benson said...

No, didn't even notice.

I chortle at the idea of damming glacial ice shelves in Antarctica.

EliRabett said...


Build the Wall. Mexico will pay for this one.

Bernard J. said...

I humbly submit my suggestion for the name of such a structure - a Canute wall.