Seawater is rushing under Thwaites Glacier, potentially dire impact on sea level | Hacker News Reader

Seawater is rushing under Thwaites Glacier, potentially dire impact on sea level

cnn.com

62 pointsgary_022 comments

Have there been any of our climate change projections that have proven too aggressive? Because most of them, this one, seem to always end up being too conservative.

I have similar thoughts in my mind while reading this. In that vein, I'd be interested to know what the 'worst case' prediction for sea level rise is, including the effects listed in the article on the Thwaites glacier; a 1 foot sea level rise in X years?

Various fossil fuel interests made a very powerful bid to cast doubt on climate science. The result was that scientists were forced to restrict their public communications to “consensus” findings that everyone could agree on, and people who considered more aggressive timelines were heavily criticized. If you consider the distribution of possible outcomes, the effect of this very deliberate effort has been to push everything to the left, in the sense of more conservative predictions. This bought the fossil fuel industries more time to pollute, at the cost of, well, everything.

Sure, the fossil fuel industry does pollute, but we are the culprits in this mess: the largest fraction of pollution actually comes from everyone that drives a gas car, flies in commercial jets, eats a meat-rich diet, and uses electricity from fossil-fueled generation. Until people--all of us--radically change these behaviors, nothing will change.

You missed a few: We also can't have anything new made out of steel, iron, or cement. And we can't have heating or cooling in our houses or businesses:

https://ourworldindata.org/ghg-emissions-by-sector

Low carbon cement and steel are absolutely possible, as is low-carbon heating and cooling. But it requires major (governmental) technological investment and a commitment to deploying the technologies.

Lots of things are possible, but the person I replied to seems to think that driving, flying, meat, and electricity are the problem. If you could magically convince every person in every country to eliminate those, you'd get:

    Road Transport:       11.9%
    Aviation:              1.9%
    Livestock:             5.8%
    Building Electrical:  17.5%

These numbers are taken from the chart I linked above, and that's aggressively rounding up in favor of their argument. I'm including things like trucks delivering food, all flights for any purpose, chicken and pork in addition to beef, and commercial buildings in addition to residential. Add it all up and it only comes to 37.1% of the total. In other words, the most charitable interpretation of their statements and it hits 1/3 of the problem.

And again, that's assuming you got every person in every country to conform. It's absurd to believe this will happen, and I don't hear anyone knowledgeable saying that eliminating 1/3 of the problem is sufficient.

Emissions in Europe and China are declining due to massive government-subsidized rollouts of renewables and massive investments (and subsidies) for EVs and charging. They are not declining because people “made and individual choice to generate lower-carbon electricity or drive EVs” which would have been pointless without the technological investments that made mass-scale EVs and renewable energy possible.

This has always been a coordination problem and “people need to make individual choices that are better” has always been the worst possible solution to it.

I vaguely remember Ozone layer predictions being pretty dire decades ago…

I am conflicted. On one hand, there is a definite “slant” to news reporting. There seems to be a short list of topics that publishers frequently and regularly publish content about, seemingly to “check a box” without really providing anything new. Whether it be “climate crisis”, “democracy”, etc…

I also dislike the coverage of CO2 emissions.. Threshold X is the goal, threshold X+0.1 is doom… There seems to be a reluctance to admit that all we’re really doing is trying to decide which generation meets the fate we fear. Buying time is certainly valuable though.

On the other hand, the scale at which humans make a mess is hard to ignore. One trash bag/ week times 100M households… where does it all go? How many tons of lead are we putting into the air from coal use? There used to be a lot more bugs when driving in rural areas at night… Could go on and on…

I feel like we should just live slightly a more simply instead of trying to “fix” climate change. The problem is not climate, it’s us.

We could decrease consumption slightly and have a better quality of life.

The plastic coffee lid or food container today will still be intact in 75 years… yet we’ll be gone. Why is that OK?

Ozone was much easier / cheaper to fix, we could keep doing what we are doing and just change it around a bit. Which is mostly what we did - there was a resurgence in freons emissions, vaguely traced to China.

The ugly truth of CO2 emissions is we would have basically needed to massively cut our energy consumption - either by going to renewables more aggressively, at a higher cost, or by outright cutting fossil fuels. We couldn't make small adjustments and keep going as we were.

So we didn't.

What's conservative about this? "Catastrophic" "doomsday glacier" doesn't sound very conservative to me.

The entire film "An Inconvenient Truth" was too aggressive, and did more damage to trust in climate science than any other publication on the topic.

Widespread seawater intrusions beneath the grounded ice of Thwaites Glacier, West Antarctica

https://www.pnas.org/doi/10.1073/pnas.2404766121

    This work was performed at the University of California Irvine and Caltech’s Jet Propulsion Laboratory under a contract with [several] NASA [programs]

"an unusually broad and vast Antarctic glacier"

"closely monitored for its potential to elevate sea levels. ...described as part of the "weak underbelly" of the West Antarctic Ice Sheet, in part because they seem vulnerable to irreversible retreat and collapse even under relatively little warming, yet also because if they go, the entire ice sheet is likely to eventually follow."

"The amount of ice from Thwaites likely to be lost in this century will only amount to several centimetres of sea level rise, but its breakdown will rapidly accelerate in the 22nd and 23rd centuries, and the volume of ice contained in the entire glacier can ultimately contribute 65 cm to global sea level rise"

https://en.wikipedia.org/wiki/Thwaites_Glacier

What's the projected timeline? I followed a chain of links (of course to other CNN articles) each titled doomsday something collapse something and couldn't find a single projected timeline. The closest I got was "it could take hundreds or thousands of years, possibly sooner" which is almost as ridiculous as measuring things using football fields.

Anybody have a timeline of a projection based on the current trend?

I remember ministry from the future book where they mention drilling down and pumping the seawater to prevent the freshwater intrusion to stop it melting

I wonder why it's not being discussed. As he said in the book, at the cost of practically all coastal cities going under, even small collections of real estate magnates would be invested enough to help privately fund at least some of it

It would be similar to trying to pump the sea out from underneath a dock. Where this is a problem the glacier is floating on the ocean.

Could someone who has domain expertise weigh in here regarding the predictions quotes in CNN? I've only ever seen two meters predicted by any model at the year 2100.

The models assume an steady rate of sea level rise because slow Antarctic ice melting. But if that glacier breaks up (because i.e. the seawater that is rushing now under it) and ends floating towards more temperate latitudes, will melt far faster than predicted, taking maybe months instead of decades.

And you should not think in average sea level rise as some line drawn in the sand. Tides, storms, that gigantic amount of fresh water starting to turning the climate even more chaotic and maybe disrupting some critical ocean ecosystems and currents. Anything that put us further away from the stable situation that led us to establish a global civilization may have very negative impacts.

If it breaks off, it raises the sea level immediately.

It is not like it is floating above sea level and a last snip makes it to fall all at once into ocean water. Or yes, I don't know, I think that probably it will be more complex than that and take its own time (up to months?) for most of it to end there. But probably the process of melting will add a new layer of problems.

Melting ice floating on water does not change the volume of the water at all. Melting will have no impact on sea level at all if the ice is already floating. It does have an impact on albedo.

Shelves and on land glaciers are structurally held up. It's when they enter a floating state that sea level rises, and this is the only time ice can cause a sea level rise. If parts of the shelf are cracked, or otherwise the water is supporting them, then they're already floating and so breaking of the parts that are floating will also have no impact.

That's what worries me the most. We have all this "extend the line" projections that say we will see mere cm rises in sea levels in this century.

I am concerned we are missing numerous potential reinforcement loops that might accelerate it. I have a gut feeling that we will see catastrophic coastal floods in the next couple of decades. I cannot shake it.

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