
Geoengineer polar glaciers to slow sea-level rise - ehudla
https://www.nature.com/articles/d41586-018-03036-4
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adaml_623
This is one of these interesting topics where people are very likely to ask,
"Have they thought of this?" And it would be great if there were a list of
discarded ideas along with the reasons for why they were discarded.

For instance I specifically would like to know if large areas of IR reflective
material could be used to cover strategic areas in the arctic and antarctic to
build up ice barriers. Coat sensitive areas with something that stops the ice
from absorbing heat and hey presto maybe you get significant gains for your
investment?

~~~
Robotbeat
Of course, ice is already very high albedo. Might be difficult to find
something better that you can directly apply to the ice.

One idea for helping to terraform Mars (by thickening the atmosphere) is to
apply black carbon dust to the glaciers. We're kind of doing that by accident
here by burning fossil fuels that produce soot that ends up on glaciers. So
reducing fossil fuel burning and soot production would help do what you're
trying to do.

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noiv
Geoengineering is just a money sink if the root cause isn't tackled. This
proposal might slow down SLR, but the oceans will continue to sour,
temperatures to rise and weather becomes more economically threatening.

~~~
mkempe
What is the exact sea-level that is perfect and should be maintained --or
returned to-- by all means?

I have a similar question about the perfect amount of atmospheric CO2. We do
know that the long-term trend of CO2 was headed down to a dangerously low
level (plants would starve and land-based plant life would have
catastrophically ended by 150ppm).

~~~
bjelkeman-again
275 million people live in cities that will be flooded if we have a 3C
warming. That is a pretty nice reason to maintain that sea level.
[https://www.theguardian.com/cities/ng-
interactive/2017/nov/0...](https://www.theguardian.com/cities/ng-
interactive/2017/nov/03/three-degree-world-cities-drowned-global-warming)

~~~
mkempe
So the current sea level is the one that must be kept? forever? or should it
rather be the level at the start of British Industrialization, let's say in
1760?

What about sea level changes that are not caused by us? should we stop that,
too? in either direction? forever?

~~~
ctrl-j
> So the current sea level is the one that must be kept?

For now, yes. There are millions of people who will be impacted if we don't.

If there is a reason to maintain a different sea level, we can weigh it
against the impact of those currently affected.

The people in 1760 are long dead, their oceans and their levels are less
relevant.

~~~
mkempe
Thanks, that makes sense as a goal, to evaluate and minimize impact on current
coastal populations. I assume future coastal population centers would actively
shift inland, over multiple decades, if they take into account predicted sea
level changes over the next 200 to 2,000 years.

~~~
ctrl-j
In a capitalist society, I wouldn't expect that. What would be the market
incentive to migrate? As it stands currently, coastal property is the most
valuable. There would need to be a mechanism to drive that migration.

Perhaps a system that adds the cost of maintaining the current sea level to
owning beachfront property?

~~~
mkempe
Market insurance without government support, and absence of emergency funding
after disasters...

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User23
We are still in an ice age and we just happen to live in an interglacial
period. The Earth has the large polar continent, and multiple other continents
arranged such that they greatly impede the free flow of water currents around
the globe that are necessary for mass glaciation. In these conditions,
glaciation can easily lead to a positive feedback loop and once that gets
going the effect is rapid (think order months to years, not decades).

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swanlyk
Isn't sea level rise mostly caused by thermal volumetric expansion not ice
melting?

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ianai
I’m increasingly of the opinion that slow is not the way to go. Too many
people refuse the existence of human caused climate change. So let them feel
the brutal, undeniable affects. Maybe we’ll luck out and we’ll pull our
collective hands off the hot iron before permanent scarring occurs.

~~~
threeseed
That isn't how this works.

The people who believe climate change the least are those that typically live
in the middle of America i.e. the least to be directly affected. I assure you
that when you speak to Pacific Islanders from Cook Islands, Fiji etc they very
much believe climate change is real and are desperate for action to be taken.

If you really want things to change help change the politicians in the US.
Because China is doubling down on solutions and we really need the US to be
doing the same.

~~~
ianai
I’m doing everything I can. But the current US political atmosphere is
depressing.

Edit-People in that middle America that you speak of seem to have forgotten
the entire Cold War and welcomed Russia as allies! I mean, the Cold War didn’t
ever end!

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mrfusion
Has there been any documented rise yet or is it supposed to start later?

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joshuahedlund
Measurements have been averaging a little above 3mm per year for the last two
decades[0]. This is believed to be about double the post-Ice-Age background
rate of a century ago, and it is predicted to accelerate further (though it
has yet to do so noticeably).

[0][http://sealevel.colorado.edu/](http://sealevel.colorado.edu/)

~~~
godshatter
In fact, that same graph used to have a trend line of 3.2 mm/yr, and is now
3.1. I've been checking in with that site off-and-on for the last few years.
At the current linear rate, we're looking at an increase of 0.25m by 2100. To
get to the 1m by 2100 that is predicted, we would have to have a linear sea
level rise of 12.4 mm/yr.

The graph displayed shows some variable years a few years ago, but it's mostly
been pretty linear. The graph shows 20 years or so of data, and we're 82 years
out from 2100. I would expect to see it curving up sometime soon, but it
hasn't done that yet.

~~~
sitkack
I would expect SLR to be highly _nonlinear_.

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John_KZ
1 meter in 100 years sounds a bit anti-climactic. With the kind of
socioeconomic problems rising it sounds kind of dumb thing to care about.
People will have decades to move and evacuate. Sure, some infrastructure will
be wasted, but it's not like the end of the world that everyone is trying to
portray.

~~~
CodeCube
Even small changes can have pretty big consequences ... for example, some
hypothesize that climate change may have had a role in the "Arab Spring" that
started a chain of events that's still unfolding in the middle east:
[https://www.americanprogress.org/issues/security/reports/201...](https://www.americanprogress.org/issues/security/reports/2013/02/28/54579/the-
arab-spring-and-climate-change/)

"“The Arab Spring and Climate Change” does not argue that climate change
caused the revolutions that have shaken the Arab world over the past two
years. But the essays collected in this slim volume make a compelling case
that the consequences of climate change are stressors that can ignite a
volatile mix of underlying causes that erupt into revolution."

TL;DR climate change contributed to changing agricultural conditions, which
led to increased migration from rural to urban centers, which was a "stressor"
that probably contributed to an already volatile situation ... the proverbial
straw that broke the camel's back (pun not necessarily intended).

So yeah, a meter of water level rise would change a massive amount of
coastlines ... which would result in population shifts, which would result in
economic activity changing, which could result in ... we'll see.

~~~
John_KZ
Of the many things might have caused the revolution, global warming wasn't one
of them. Egypt is at a country's developmental phase when urbanization
happens. Also it takes a lot of confidence to attribute 2 years of dryness to
climate change. I'm trying to keep my composure but this is a laughable
statement.

Here's a neat little tool I found:
[http://flood.firetree.net/](http://flood.firetree.net/)

I guess that by 2100 the only problems my area will run into is a couple of
deltas being flooded by saltwater and a few random patches of 50m incursions,
all but one uninhabited. I think I'll survive, and my children will probably
be fine.

