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Miles of Ice Collapsing Into the Sea

nytimes.com

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Re: Miles of Ice Collapsing Into the Sea

#21

Post by oldandtired »

The article was interesting in that it use the word "could". In context, the only ice that will contribute to sea level rises is land based. We could lose all the sea based ice and the overall effect most likely will be a drop in sea level.

To get a 1 metre sea level rise, requires the melting of land based ice of a volume equivalent to the entire surface area of Australia covered to a depth of 45 metres or so. The energy requirements for phase conversion is at least 1 million 25 MegaTonne nuclear bombs going off,

Based on every relevant paper on the subject that I have been able to find, and it appears that it would take anywhere between 1000 and 3500 years before we would get this 1 metre rise.

The last set of figures that I saw from the IPCC is that it would be about 1000 years to see this kind of rise, if their measurements were correct.

The thing I find interesting is that we (as humans) have a very short term memory of what has happened in the past. Especially, when things are driven by authoritative groups such as governments (and attendant bureaucracies) and science committees and panels.

Re: Miles of Ice Collapsing Into the Sea

#22

Post by flukus »

oldandtired wrote: post #21

The article was interesting in that it use the word "could". In context, the only ice that will contribute to sea level rises is land based. We could lose all the sea based ice and the overall effect most likely will be a drop in sea level. To get a 1 metre sea level rise, requires the melting of land based ice of a volume equivalent to the entire surface area of Australia covered to a depth of 45 metres or so. The e…

> The article was interesting in that it use the word "could". In context, the only ice that will contribute to sea level rises is land based. We could lose all the sea based ice and the overall effect most likely will be a drop in sea level.

These shelves are built from ice that has flowed from land to out over the ocean, the more it melts the more that flow increases and the more ice goes from being on land to being in the ocean.

> To get a 1 metre sea level rise, requires the melting of land based ice of a volume equivalent to the entire surface area of Australia covered to a depth of 45 metres or so. The energy requirements for phase conversion is at least 1 million 25 MegaTonne nuclear bombs going off,

There was a thunderf00t video very recently on this topic (sorry I can't link to it from work), I forget the exact figures that he came too but the energy effect of global warming was on the order of thousands of megatonne bombs a second.

Re: Miles of Ice Collapsing Into the Sea

#23

Post by oldandtired »

flukus wrote: post #22
oldandtired wrote: post #21

The article was interesting in that it use the word "could". In context, the only ice that will contribute to sea level rises is land based. We could lose all the sea based ice and the overall effect most likely will be a drop in sea level. To get a 1 metre sea level rise, requires the melting of land based ice of a volume equivalent to the entire surface area of Australia covered to a depth of 45 metres or so. The e…

> The article was interesting in that it use the word "could". In context, the only ice that will contribute to sea level rises is land based. We could lose all the sea based ice and the overall effect most likely will be a drop in sea level. These shelves are built from ice that has flowed from land to out over the ocean, the more it melts the more that flow increases and the more ice goes from being on land to bein…

My comment about the 1 million bombs is related to just the amount of energy required to convert solid water to liquid water at 0 degrees Celsius.

The figures that I have seen from various studies indicate that only a very small amount of the energy stored in water ever gets to actually meting ice.

In regards to the ice flows, the flow is caused by evaporated water from the oceans being deposited on the land at the glacier. Without that depositing of water vapour, there is no flow. Hence, until a determined study is made on the full dynamics of this cycle, mayhaps one should not be using this as the driving example or even as an example.

Re: Miles of Ice Collapsing Into the Sea

#24

Post by propman »

jcranmer wrote: post #19
propman wrote: post #10

Serious question, if sea level increases are so damaging and feared is it possible to build a water pipeline (like an oil pipeline) from higher coastland to a lower area and then create an artificial river to use in an artificial dam. I think estimates put sea levels rising at around 3 mm a year. I did the rough math and 3mm cubed is a lot but I think it can be doable for $15B and the potential artificial dam might b…

There isn't a significant amount of land below sea level, because most of the planet's surface is already ocean and the saddle point being below sea level will flood it. Effectively, the most significant amounts of land below sea-level are nascent rift zones that haven't connected to the ocean yet. The sum total of significant depressions: * Salton Sea (~21700 km², sea surface ~70 m below sea-level) * Death Valley (~…

Great info and so many other great answers and fun reading. Okay so the Afar Depression would be the equivalent of 12 years of current sea rise increases. It would require many tens of Kms worth of canals but in return could create a lot of hydro power. It would have lots of negatives like another commenter mentioned but also a few others primarily earthquake issues and awful impact on local environment.

Overall, if it was a life and death situation not the worst solution in the world. We are probably good till 2050 and this could add another 12 years. We get 20% of our energy from nuclear and I hope both sides see the need for it and if we can get it to 60% and reach 300 nuclear reactors & cut down prices back to 2008 levels to $3B each and help China and India build theirs we should be in a great state.

Re: Miles of Ice Collapsing Into the Sea

#25

Post by propman »

kijin wrote: post #13
propman wrote: post #10

Serious question, if sea level increases are so damaging and feared is it possible to build a water pipeline (like an oil pipeline) from higher coastland to a lower area and then create an artificial river to use in an artificial dam. I think estimates put sea levels rising at around 3 mm a year. I did the rough math and 3mm cubed is a lot but I think it can be doable for $15B and the potential artificial dam might b…

Sure, we could flood the Death Valley and Salton Sea in California, the Dead Sea and most of the Jordan Valley, the Afar Depression, the Caspian Sea, and large parts of the Netherlands. The problem of course is that most of these lands are inhabited. You're just trading one parcel of land for another, one group of displaced people with another, one group of endangered species with another. There's also the question o…

We could use it for hydro power. I think of these only Afar Depression would have substantial impact and feasibility. Worth 12 years of current estimates of sea rises

Re: Miles of Ice Collapsing Into the Sea

#26

Post by propman »

therealdrag0 wrote: post #12
propman wrote: post #10

Serious question, if sea level increases are so damaging and feared is it possible to build a water pipeline (like an oil pipeline) from higher coastland to a lower area and then create an artificial river to use in an artificial dam. I think estimates put sea levels rising at around 3 mm a year. I did the rough math and 3mm cubed is a lot but I think it can be doable for $15B and the potential artificial dam might b…

If I understand you correctly you're suggesting treating the ocean like an elevated lake, and putting a pipe to a lower place so the water pressure could generate electricity. The two things that come to mind for me are: 1. It's hard to find land lower than the ocean ( https://en.wikipedia.org/wiki/List_of_places_on_land_with_el... ) 2. Piping salty ocean water inland will make a lot of people unhappy. It would total…

Yeah so the Afar Depression would be feasible and would stop 12 years worth of ocean rises and create a lot of power, but would cause a lot of costs and issues to the area. I thought Death Valley was huge but only stops around 3mm of ocean so just 1 year of the current rise rate
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