Meeting Paris Agreement ambition could save a lot of sea level rise

Latest models project a bumpy road with big risks.

Read the whole story

 

[graylshaped]

Or, we could re-elect Covfece and swamp Florida. Both have their downsides.

Personally, I say let's be responsible stewards of the planet.

 

[Azethoth666]

I have a question about the flooding of the below sea level basins. How fast is the rebound in such a scenario? We are able to measure the effect of water in California in drought and non drought years. Does that help predict it? That is, how long before rebound pushes the land back up, and adds that entire volume to the whole flooding disaster as well?

Naively I expect it to be a slow process like continental drift, but faster than that because it's simple buoyancy?

 

[Personne]

Antarctica is obviously the largest water reserve but let's not forget the Greenland contribution. The global ocean rise will exceed the numbers shown here. Mind boggling.

 

[SydBarrett]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

Miami is already having issues with sinking land. New Orleans is under sea level. NYC flooded with superstorm Sandy. It's only going to get worse.

 

[Azethoth666]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

The average elevation of Florida is 72 inches. Some places are 36 inches.

Yeah, wow, how could we ever cope with that? The lower parts of Florida have vast amounts of buffer height. I mean it would take another 2 rises of 12" before those parts are permanently underwater.

Why would Florida possibly have to worry about this in the future? They are already handling it. See with your own lying eyes!

PS: the worst case is 18", so there is also the part where you did not even read the whole article.

 

[DukeOfGeeks]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

Miami is already having issues with sinking land. New Orleans is under sea level. NYC flooded with superstorm Sandy. It's only going to get worse.

Remediation is either a fading dream or an active delusion.

Mitigation is all that's left.

 

[ScottJohnson]

I have a question about the flooding of the below sea level basins. How fast is the rebound in such a scenario? We are able to measure the effect of water in California in drought and non drought years. Does that help predict it? That is, how long before rebound pushes the land back up, and adds that entire volume to the whole flooding disaster as well?

Naively I expect it to be a slow process like continental drift, but faster than that because it's simple buoyancy?

It is a plate-tectonics-ish speed, but this is definitely an important consideration. It can displace water, it can also change the shape of the bed beneath the ice, how much of the ice is supported by floating, etc.

http://www.antarcticglaciers.org/glacie ... n-ice-age/
https://advances.sciencemag.org/content/7/18/eabf7787
https://www.nature.com/articles/ncomms9798

 

[MarkR_]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

The average elevation of Florida is 72 inches. Some places are 36 inches.

Yeah, wow, how could we ever cope with that? The lower parts of Florida have vast amounts of buffer height. I mean it would take another 2 rises of 12" before those parts are permanently underwater.

Why would Florida possibly have to worry about this in the future? They are already handling it. See with your own lying eyes!

PS: the worst case is 18", so there is also the part where you did not even read the whole article.

It seems like the risks in S. Florida are going to be "hidden" by the lunar nodal cycle for the next few years.

The lunar effect is currently in a downcycle, knocking about an inch (~2.5 cm) off high-tide levels over the coming 4 years.

The next peak is 2035, I'd place a bet on people freaking out by then. If I had Florida real estate I'd consider getting the hell out of there in the mid-2020s.

 

[pea nut]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

Every time people feel the need to speak and remove all doubt about their powers of understanding the way you do, I point them in the direction of insurance premiums in the affected areas.
We are at a point where opening a business in some coastal locations might not be viable because insurance is simply too expensive - if you manage to get it at all.
Educate yourself.

 

[MarkR_]

I'd ask everyone to notice how there's no slowdown in sight once you approach 2100.

This is going to do weird things to insurance and real estate prices. Sure, your house might not be underwater right now but if you want to sell it then you need to find a buyer who might expect to get $0 back in land value when they come to sell.

A stopgap pumping measure in Miami Beach is slated to run about $5k per person.

 

[Fatesrider]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

Most everyone will notice.

What you fail to grasp is the impact on tides, storm surges, coastal erosion, water tables, wetlands, water treatment plants, docks and harbors and places like Venice, and 11 other sinking cities that will be made much worse by an extra foot of ocean level.

Not to mention the additional water vapor and heat energy making storms stronger, with weakened jet streams making them last longer over a given spot and dump more rain, creating catastrophic flooding inland.

God, did you just decide to go full retard on your post? That's the stupidest thing I've seen anyone ever post on Ars.

 

[Batmanuel]

So long as Mar-A-Lago is underwater within Trump’s lifetime, I’ll be satisfied.

 

[Rindan]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

Miami is already having issues with sinking land. New Orleans is under sea level. NYC flooded with superstorm Sandy. It's only going to get worse.

Remediation is either a fading dream or an active delusion.

Mitigation is all that's left.

The nation of Netherlands would like to disagree. Remember that time they recovered nearly half of their nation from the ocean starting the 1500s?

Let's not let gloom over global warming transform into a sense of helplessness and pretend like the only mitigation effort you can take is to stop dumping CO2 or simply die. You can in fact build sea defenses in many places, with a cities like New York being an obvious candidate for a place well worth defending from the sea rather than retreating from it.

I too want to reduce our CO2 emissions, and that certainly is the best solution, but I loath how the climate change movement has adopted an abstinence only approach to dealing with climate change, and get angry if someone suggests expresses any other opinion than totally helpless before changing climate.

Lots of places can't deal with a sea level rise and will have to evacuate before rising waters, but New York City is not one of those places, because we will defend it, as we are more than capable of doing.

 

[Geburtenfresser]

I have a question about the flooding of the below sea level basins. How fast is the rebound in such a scenario? We are able to measure the effect of water in California in drought and non drought years. Does that help predict it? That is, how long before rebound pushes the land back up, and adds that entire volume to the whole flooding disaster as well?

Naively I expect it to be a slow process like continental drift, but faster than that because it's simple buoyancy?

So, Scandinavia is still rising from after the last ice age, when its continental glaciers that covered most of the land mass started to melt. To give you an idea of the timeframe.

 

[Veritas super omens]

It is unclear to me if these scenarios only account for sea level rise from Antarctic sources or if the thermal expansion and other glacial waters (eg Greenland) are included in the models posited.

Also the sentence "Still, future sea level rise is fundamentally uncertain." is slightly misleading. Knowing the authors expertise, I'm sure he means "Still, the amount of future sea level rise is fundamentally uncertain."
because it is certain it will rise.

 

[Toastr]

It is unclear to me if these scenarios only account for sea level rise from Antarctic sources or if the thermal expansion and other glacial waters (eg Greenland) are included in the models posited.

Also the sentence "Still, future sea level rise is fundamentally uncertain." is slightly misleading. Knowing the authors expertise, I'm sure he means "Still, the amount of future sea level rise is fundamentally uncertain."
because it is certain it will rise.

It wasn't mentioned in the article, but I looked through the paper and it looks like it did include Greenland. Also, the author was cool enough to link to the GitHub repository with the R code used for the simulations as well as the input data.

 

[Oldmanalex]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

Miami is already having issues with sinking land. New Orleans is under sea level. NYC flooded with superstorm Sandy. It's only going to get worse.

Remediation is either a fading dream or an active delusion.

Mitigation is all that's left.

The nation of Netherlands would like to disagree. Remember that time they recovered nearly half of their nation from the ocean starting the 1500s?

Let's not let gloom over global warming transform into a sense of helplessness and pretend like the only mitigation effort you can take is to stop dumping CO2 or simply die. You can in fact build sea defenses in many places, with a cities like New York being an obvious candidate for a place well worth defending from the sea rather than retreating from it.

I too want to reduce our CO2 emissions, and that certainly is the best solution, but I loath how the climate change movement has adopted an abstinence only approach to dealing with climate change, and get angry if someone suggests expresses any other opinion than totally helpless before changing climate.

Lots of places can't deal with a sea level rise and will have to evacuate before rising waters, but New York City is not one of those places, because we will defend it, as we are more than capable of doing.

There are places you can build defenses, and places where you cannot. All places will cost money. NYC may be largely protectable from sea rise, but will it be protectable from heavy precipitation in the Hudson water basin 48 hours before a high tide? Will the Jersey shore be defendable at all? And as for the fractured limestone that reflects much of Florida, Fuggedaboudit.

 

[ScottJohnson]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

Miami is already having issues with sinking land. New Orleans is under sea level. NYC flooded with superstorm Sandy. It's only going to get worse.

Remediation is either a fading dream or an active delusion.

Mitigation is all that's left.

The nation of Netherlands would like to disagree. Remember that time they recovered nearly half of their nation from the ocean starting the 1500s?

Let's not let gloom over global warming transform into a sense of helplessness and pretend like the only mitigation effort you can take is to stop dumping CO2 or simply die. You can in fact build sea defenses in many places, with a cities like New York being an obvious candidate for a place well worth defending from the sea rather than retreating from it.

I too want to reduce our CO2 emissions, and that certainly is the best solution, but I loath how the climate change movement has adopted an abstinence only approach to dealing with climate change, and get angry if someone suggests expresses any other opinion than totally helpless before changing climate.

Lots of places can't deal with a sea level rise and will have to evacuate before rising waters, but New York City is not one of those places, because we will defend it, as we are more than capable of doing.

Adaptation only was never an option. Mitigation only hasn't been an option for a very long time. We are already having to adapt.

 

[ScottJohnson]

It is unclear to me if these scenarios only account for sea level rise from Antarctic sources or if the thermal expansion and other glacial waters (eg Greenland) are included in the models posited.

Also the sentence "Still, future sea level rise is fundamentally uncertain." is slightly misleading. Knowing the authors expertise, I'm sure he means "Still, the amount of future sea level rise is fundamentally uncertain."
because it is certain it will rise.

It wasn't mentioned in the article, but I looked through the paper and it looks like it did include Greenland. Also, the author was cool enough to link to the GitHub repository with the R code used for the simulations as well as the input data.

Sorry if it wasn't clear--the second study is global (all land ice) but neither models thermal expansion.

 

[Rindan]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

Miami is already having issues with sinking land. New Orleans is under sea level. NYC flooded with superstorm Sandy. It's only going to get worse.

Remediation is either a fading dream or an active delusion.

Mitigation is all that's left.

The nation of Netherlands would like to disagree. Remember that time they recovered nearly half of their nation from the ocean starting the 1500s?

Let's not let gloom over global warming transform into a sense of helplessness and pretend like the only mitigation effort you can take is to stop dumping CO2 or simply die. You can in fact build sea defenses in many places, with a cities like New York being an obvious candidate for a place well worth defending from the sea rather than retreating from it.

I too want to reduce our CO2 emissions, and that certainly is the best solution, but I loath how the climate change movement has adopted an abstinence only approach to dealing with climate change, and get angry if someone suggests expresses any other opinion than totally helpless before changing climate.

Lots of places can't deal with a sea level rise and will have to evacuate before rising waters, but New York City is not one of those places, because we will defend it, as we are more than capable of doing.

Adaptation only was never an option. Mitigation only hasn't been an option for a very long time. We are already having to adapt.

Yes that is literally what I said, and we apparently agree that OP was flatly wrong when they said migration was the only option left, and you appear to agree with me when I said that some places can be defended and some can't.

 

[ScottJohnson]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

Miami is already having issues with sinking land. New Orleans is under sea level. NYC flooded with superstorm Sandy. It's only going to get worse.

Remediation is either a fading dream or an active delusion.

Mitigation is all that's left.

The nation of Netherlands would like to disagree. Remember that time they recovered nearly half of their nation from the ocean starting the 1500s?

Let's not let gloom over global warming transform into a sense of helplessness and pretend like the only mitigation effort you can take is to stop dumping CO2 or simply die. You can in fact build sea defenses in many places, with a cities like New York being an obvious candidate for a place well worth defending from the sea rather than retreating from it.

I too want to reduce our CO2 emissions, and that certainly is the best solution, but I loath how the climate change movement has adopted an abstinence only approach to dealing with climate change, and get angry if someone suggests expresses any other opinion than totally helpless before changing climate.

Lots of places can't deal with a sea level rise and will have to evacuate before rising waters, but New York City is not one of those places, because we will defend it, as we are more than capable of doing.

Adaptation only was never an option. Mitigation only hasn't been an option for a very long time. We are already having to adapt.

Yes that is literally what I said, and we apparently agree that OP was flatly wrong when they said migration was the only option left, and you appear to agree with me when I said that some places can be defended and some can't.

I'd just add that "defended" is a relative term for expenditures significantly less than infinity. We defended New Orleans until we didn't, for example.

 

[Rindan]

Miami is already having issues with sinking land. New Orleans is under sea level. NYC flooded with superstorm Sandy. It's only going to get worse.

Remediation is either a fading dream or an active delusion.

Mitigation is all that's left.

The nation of Netherlands would like to disagree. Remember that time they recovered nearly half of their nation from the ocean starting the 1500s?

Let's not let gloom over global warming transform into a sense of helplessness and pretend like the only mitigation effort you can take is to stop dumping CO2 or simply die. You can in fact build sea defenses in many places, with a cities like New York being an obvious candidate for a place well worth defending from the sea rather than retreating from it.

I too want to reduce our CO2 emissions, and that certainly is the best solution, but I loath how the climate change movement has adopted an abstinence only approach to dealing with climate change, and get angry if someone suggests expresses any other opinion than totally helpless before changing climate.

Lots of places can't deal with a sea level rise and will have to evacuate before rising waters, but New York City is not one of those places, because we will defend it, as we are more than capable of doing.

Adaptation only was never an option. Mitigation only hasn't been an option for a very long time. We are already having to adapt.

Yes that is literally what I said, and we apparently agree that OP was flatly wrong when they said migration was the only option left, and you appear to agree with me when I said that some places can be defended and some can't.

I'd just add that "defended" is a relative term for expenditures significantly less than infinity. We defended New Orleans until we didn't, for example.

Yes, that is what "some places can be defend and some can't" means. We both agree that OP was wrong when they said that migration was the only option left, and we both agree that some places can and will obviously be defended, while others will not.

It's like you are trying to turn my nuanced rejection of OPs absolutist statement (that we both agree was wrong) into an absolutist statement that it was not. Maybe you should be be trying to inject nuance to the people making absurd claims like "Mitigation is all that's left." rather than the people who are already making a nuanced statement that you appear to literally and completely agree with.

 

[ScottJohnson]

Remediation is either a fading dream or an active delusion.

Mitigation is all that's left.

The nation of Netherlands would like to disagree. Remember that time they recovered nearly half of their nation from the ocean starting the 1500s?

Let's not let gloom over global warming transform into a sense of helplessness and pretend like the only mitigation effort you can take is to stop dumping CO2 or simply die. You can in fact build sea defenses in many places, with a cities like New York being an obvious candidate for a place well worth defending from the sea rather than retreating from it.

I too want to reduce our CO2 emissions, and that certainly is the best solution, but I loath how the climate change movement has adopted an abstinence only approach to dealing with climate change, and get angry if someone suggests expresses any other opinion than totally helpless before changing climate.

Lots of places can't deal with a sea level rise and will have to evacuate before rising waters, but New York City is not one of those places, because we will defend it, as we are more than capable of doing.

Adaptation only was never an option. Mitigation only hasn't been an option for a very long time. We are already having to adapt.

Yes that is literally what I said, and we apparently agree that OP was flatly wrong when they said migration was the only option left, and you appear to agree with me when I said that some places can be defended and some can't.

I'd just add that "defended" is a relative term for expenditures significantly less than infinity. We defended New Orleans until we didn't, for example.

Yes, that is what "some places can be defend and some can't" means. We both agree that OP was wrong when they said that migration was the only option left, and we both agree that some places can and will obviously be defended, while others will not.

It's like you are trying to turn my nuanced rejection of OPs absolutist statement (that we both agree was wrong) into an absolutist statement that it was not. Maybe you should be be trying to inject nuance to the people making absurd claims like "Mitigation is all that's left." rather than the people who are already making a nuanced statement that you appear to literally and completely agree with.

I'm not arguing with you, I just wanted to add points to an interesting thread.

 

[DukeOfGeeks]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

Miami is already having issues with sinking land. New Orleans is under sea level. NYC flooded with superstorm Sandy. It's only going to get worse.

Remediation is either a fading dream or an active delusion.

Mitigation is all that's left.

The nation of Netherlands would like to disagree. Remember that time they recovered nearly half of their nation from the ocean starting the 1500s?

That is my point. We can mitigate the affects; I don't think we can stop or even greatly slow the process. By all means we should try to do so; flattening THIS curve eventually is gonna have to happen. But we shouldn't count on it turning anything around. We need to spend our climate change $$$$ as much on moving people to higher ground (or walling off the low ground, but eventually the sea always wins), finding ways to desalinate farm land, better ways of managing water is just as important as nuclear, wind, tide and solar power and finding a way to cycle carbon out.

 

[khumak50]

I think it's good to have a range of plausible scenarios for how much sea level increase we could expect under the most likely range of scenarios, but one scenario that I don't see highlighted often enough is basically the worst case scenario that I don't think many people are aware of. If we ignore global warming entirely and just let the temperature keep rising, what happens when ALL of the ice caps melt? In that sort of scenario we're not talking sea level increases measured in centimeters or inches, we're talking more like 200 feet.

We won't see that level of increase under even the most pessimistic projections any time soon, but that's the endgame if we do nothing. People complain about the cost of fighting global warming, but what's the cost of every coastal city on earth being destroyed by sea level increase, not to mention things like food shortages and all the other problems directly caused by higher temps?

 

[Fatesrider]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

Miami is already having issues with sinking land. New Orleans is under sea level. NYC flooded with superstorm Sandy. It's only going to get worse.

Remediation is either a fading dream or an active delusion.

Mitigation is all that's left.

The nation of Netherlands would like to disagree. Remember that time they recovered nearly half of their nation from the ocean starting the 1500s?

Let's not let gloom over global warming transform into a sense of helplessness and pretend like the only mitigation effort you can take is to stop dumping CO2 or simply die. You can in fact build sea defenses in many places, with a cities like New York being an obvious candidate for a place well worth defending from the sea rather than retreating from it.

I too want to reduce our CO2 emissions, and that certainly is the best solution, but I loath how the climate change movement has adopted an abstinence only approach to dealing with climate change, and get angry if someone suggests expresses any other opinion than totally helpless before changing climate.

Lots of places can't deal with a sea level rise and will have to evacuate before rising waters, but New York City is not one of those places, because we will defend it, as we are more than capable of doing.

The sea level rise will inundate low-lying lands like the Netherlands. They've never dealt with significant sea level changes. All they did was put up dykes and pump out the water. The hydraulic forces remained stable throughout their history, meaning the effects of the ocean being kept at bay remained the same.

This won't happen with sea level rises.

The static nature of the forces will change to dynamic, and increasing. That will have a direct, and increasing, impact on the erosion levels of the dykes, the ground water quality, the impacts of storm surges and tides and the costs associated with keeping the water at bay.

To illustrate the point, you can think of the Netherlands as a weak water hose with a restricted outlet. The amount of water flowing through it is constant. But increase the amount of water and the outlet prevents that from escaping. It's not a matter of "more pumps". It's a matter of hydraulic pressure on the ground surfaces and footings of the dykes and passive flood control measures. Eventually, the amount of water pressure on the hose is too much, and the hose breaks.

Exactly where that point is can probably be calculated, but I don't have the figures or variables to do that. It's just that water pressure through soil and rock increases, especially when the water is above that soil and rock pressing down on it.

But assuming it's actually technologically possible to defy significant sea level increases with dykes and such, the costs would be prohibitive, and the consequences of a failure of that technology beyond catastrophic.

So while I won't rule out the possibility, extremely remote, given today's level of technology, to apply a technological fix to rising sea levels for low-lying parts of a country, the costs of doing that will not be affordable for any country. Tidal wave barriers don't expect to keep back water indefinitely, and are extremely expensive to build (not to mention, due to the carbon released from concrete, exceptionally bad for reducing carbon emissions), and they're the closest things to a partial fix that mankind has today. Earthen barriers will crumble or erode. There's not enough steel in the world to withstand salt water long enough to do the job.

The only viable, affordable, and practical means to deal with the issue is to move the damned cities to higher ground. If that means moving a country inland, or seeing it disappear forever (or at least until the next ice age), then relocation of the population is all that's left.

We are at the point where mitigation won't keep global temperatures below the Paris Accords levels, and 3C by the end of the century is now considered inevitable (pending the creation of some really radical, and effective, atmospheric carbon reduction tech that isn't there yet, and even that may not be enough with climate inertia being a thing). Adaptation is necessary already, and the need for that is growing daily. That's not building taller dykes. That's relocating cities away from coastlines and allowing the seas to swallow what we once walked upon, and learning from our mistakes.

 

[raptgamer]

Slightly off topic, but has anyone determined the effect on Earths rotational speed from transferring the ice mass from the poles to being spread over the ocean surfaces?
How many seconds could be added to each day?

 

[Toastr]

I think it's good to have a range of plausible scenarios for how much sea level increase we could expect under the most likely range of scenarios, but one scenario that I don't see highlighted often enough is basically the worst case scenario that I don't think many people are aware of. If we ignore global warming entirely and just let the temperature keep rising, what happens when ALL of the ice caps melt?

That's more or less what the RCP8.5 scenario in the article is: a worst-case scenario. It's named that because it's based on 8.5° C of warming 8.5 W/m2 of radiative forcing by the end of the century (thanks to Jiveformation for the correction), which is basically what we'd expect if emissions continued to rise throughout the period with zero mitigation. As the article mentions, the uncertainty is pretty huge, but even based on that RCP8.5 scenario (bottom right graph) there's basically no chance the ice caps will melt entirely in the next century (or even the next three centuries).

That said, you're right that if all the Antarctic and glacial ice in the world did melt entirely there would be roughly 70 meters (230 feet) of sea level rise.

 

[real mikeb_60]

I think it's good to have a range of plausible scenarios for how much sea level increase we could expect under the most likely range of scenarios, but one scenario that I don't see highlighted often enough is basically the worst case scenario that I don't think many people are aware of. If we ignore global warming entirely and just let the temperature keep rising, what happens when ALL of the ice caps melt?

That's more or less what the RCP8.5 scenario in the article is: a worst-case scenario. It's named that because it's based on 8.5° C of warming, which is basically what we'd expect if emissions continued to rise throughout the next century with zero mitigation. As the article mentions, the uncertainty is pretty huge, but even based on that RCP8.5 scenario (bottom right graph) there's basically no chance the ice caps will melt entirely in the next century (or even the next three centuries).

That said, you're right that if all the Antarctic and glacial ice in the world did melt entirely there would be roughly 70 meters (230 feet) of sea level rise.

Roughly is right. The rebound effect, especially in Antarctica but also Greenland, is apparently a fairly recent addition to the modeling. One wonders, considering thin crust and shallow mantle, whether continental breakup of Antarctica might occur, with loss of the ice holding everything down, leading to an Iceland- or East Africa-like situation of volcanoes and rift zones and potentially a world-wide revision of plate tectonics. Over a geologically short but sociologically infinite time scale. Plate movement directions have changed before, but I haven't seen any clear discussion of causes.

The real question is how fast we can lose the ice sheets. IIRC from previous articles, the Eocene maximum, at least briefly, had no glaciers on land, anywhere. Geologically it came on very quickly, though not instantaneous as in a complete collapse (or the rate we're increasing temps). Beginning to wonder if the San Francisco Archipelago scenario alternative future history timing might only be off by decades rather than hundreds or thousands of years, in a worst case not yet modeled.

 

[real mikeb_60]

Slightly off topic, but has anyone determined the effect on Earths rotational speed from transferring the ice mass from the poles to being spread over the ocean surfaces?
How many seconds could be added to each day?

Could be calculated. It's been calculated after large subduction-zone quakes that change the distribution of mass.

 

[Abhi Beckert]

Coastal cities will still be there. Most no one will notice.

My coastal city already floods whenever there's an especially high tide. Lift up the manholes on the pavement on a normal day and the water level can be half a foot under the ground level, with data/power/etc cables fully submerged.

It also interacts with rain. Stormwater drains are nearly useless if the sea level is too close to the ground level.

 

[itfa]

9-12 inches in 80 years!

Wow how can we ever cope with that?

Coastal cities will still be there. Most no one will notice.

The average elevation of Florida is 72 inches. Some places are 36 inches.

Yeah, wow, how could we ever cope with that? The lower parts of Florida have vast amounts of buffer height. I mean it would take another 2 rises of 12" before those parts are permanently underwater.

Why would Florida possibly have to worry about this in the future? They are already handling it. See with your own lying eyes!

PS: the worst case is 18", so there is also the part where you did not even read the whole article.

That's not even remotely accurate. Keith London isn't doing anybody any favors by throwing out bogus figures like that. It does nothing but give fodder to climate change deniers. Florida's average elevation is closer to a hundred feet than it is to 6.

 

[Dputiger]

That's not even remotely accurate. Keith London isn't doing anybody any favors by throwing out bogus figures like that. It does nothing but give fodder to climate change deniers. Florida's average elevation is closer to a hundred feet than it is to 6.

While it's true that Florida's mean elevation is 100 feet, it's 49th in the country for elevation -- and you lose a *huge* chunk of it when ocean levels rise.

https://www.miamiherald.com/news/nation ... 47252.html

At 15 feet, you lose 1/3 to 1/2 the state.

 

[Bernardo Verda]

That's not even remotely accurate. Keith London isn't doing anybody any favors by throwing out bogus figures like that. It does nothing but give fodder to climate change deniers. Florida's average elevation is closer to a hundred feet than it is to 6.

While it's true that Florida's mean elevation is 100 feet, it's 49th in the country for elevation -- and you lose a *huge* chunk of it when ocean levels rise.

https://www.miamiherald.com/news/nation ... 47252.html

At 15 feet, you lose 1/3 to 1/2 the state.

Is the mean elevation actually all that meaningful?
I would think that under the circumstances, the median and the mode are both much more relevant figures for real life planning.

 

[C64 raids Bungling Bay]

The answer is simple. Just pump sea water from the warm coastal rim to the cold interior of Antarctica. I'd go nuclear plant for the pumps, but there is a lot of wind energy from the cold winds blowing down to lower elevation.

Now the bad news: you only need about 362 km^3 of water pumped for each mm of sea level rise.

http://www.antarcticglaciers.org/glacie ... evel-rise/

Sarcastic? Not really. Impractical, most likely. But Elon might make it work, if you tell him Bezos is ahead of him in trying it.

(Fixed link, and added gripe about cm's. Inches, feet, or proper MKS SI units please)

 

[Bonobob]

I have a question about the flooding of the below sea level basins. How fast is the rebound in such a scenario? We are able to measure the effect of water in California in drought and non drought years. Does that help predict it? That is, how long before rebound pushes the land back up, and adds that entire volume to the whole flooding disaster as well?

Naively I expect it to be a slow process like continental drift, but faster than that because it's simple buoyancy?

I can't give you exact figures for how fast the rebound would be, but Canada is still rebounding from the last ice age.

 

[spoof]

I'd ask everyone to notice how there's no slowdown in sight once you approach 2100.

This is going to do weird things to insurance and real estate prices. Sure, your house might not be underwater right now but if you want to sell it then you need to find a buyer who might expect to get $0 back in land value when they come to sell.

A stopgap pumping measure in Miami Beach is slated to run about $5k per person.

The wealthy simply decamp and move elsewhere as they have done throughout history.

They don't share your concerns. Even unto the end of the world. There's always beachfront property somewhere else.