We are approaching the tipping point': Marker for the collapse of key Atlantic current discovered

[Admin]

A vital Atlantic current that includes the Gulf Stream and keeps our climate in check may be giving off a warning sign of collapse.

We are approaching the tipping point': Marker for the collapse of key Atlantic current discovered : Read more

 

[Unclear Engineer]

I am still waiting for a global climate model to be able to backcast the ice age history as found in geological evidences.

Articles like this one seem to say that the "tipping point" is heading towards massive cooling of the northern hemisphere. Which sounds a lot like the beginning of an ice age, not the global climate "melt-down" of insufferably high temperatures everywhere that are the angst of "global warming" activists.

Another disparity in this particular article is "sediment records over the past 100,000 years suggest that, at times, the AMOC has shut down abruptly, leading to major climate shifts over mere decades." But the last 100,000 years was the last "ice age", at least up to about 20,000 years ago. So, if this happens during ice ages, is it really a "global warming" issue? And, if it has happened before, why is it something that we can "prevent" by changing our emissions?

For some time, there has been a "snow blitz" theory for the beginning of ice ages that has enhanced snowfalls in the northern latitudes change the albedo sufficiently to initiate a new ice age by reflecting much of the summer insolation back into space, keeping the northern summers very cold. The theory originally was counting on the Arctic Ocean to become ice-free, so that it could provide moisture for the massive snow production. Since the Arctic ice does seem to be melting away, combining that with the cooling due to the Atlantic Meridional Overturning Circulation stopping would seem to be a good reason to suspect the onset of a new ice age. Is that what has been happening repeatedly over the last few million years? Will more CO2 in the atmosphere change this cycle - and if so, in what ways?

Humans will suffer no matter how the climate and sea level and rainfall patterns change, because we have so much expensive infrastructure built around the existing conditions, and such a high global population that there is no room to just move to a better place when one place becomes less hospitable while others become more hospitable.

But, my expectation is that we will see some pretty massive changes, no matter what we do. Even without contributions from human activities, sea levels have reached higher values in the previous interglacial periods - 25 feet higher than today about 120,000 years ago, and even higher in prior interglacial periods. We need to expect sea level to rise, and rise a lot. The only question is how fast, and how high. And, I have read that the Gulf Stream stopping would raise sea level by about 5 feet where I live, which would make my own home flood on every high tide. This article seems to say that could happen fast enough that a lot of people on the east coast of the U.S. could be flooded out in the next decade.

 

[Atlan0001]

I am still waiting for a global climate model to be able to backcast the ice age history as found in geological evidences.

Articles like this one seem to say that the "tipping point" is heading towards massive cooling of the northern hemisphere. Which sounds a lot like the beginning of an ice age, not the global climate "melt-down" of insufferably high temperatures everywhere that are the angst of "global warming" activists.

Another disparity in this particular article is "sediment records over the past 100,000 years suggest that, at times, the AMOC has shut down abruptly, leading to major climate shifts over mere decades." But the last 100,000 years was the last "ice age", at least up to about 20,000 years ago. So, if this happens during ice ages, is it really a "global warming" issue? And, if it has happened before, why is it something that we can "prevent" by changing our emissions?

For some time, there has been a "snow blitz" theory for the beginning of ice ages that has enhanced snowfalls in the northern latitudes change the albedo sufficiently to initiate a new ice age by reflecting much of the summer insolation back into space, keeping the northern summers very cold. The theory originally was counting on the Arctic Ocean to become ice-free, so that it could provide moisture for the massive snow production. Since the Arctic ice does seem to be melting away, combining that with the cooling due to the Atlantic Meridional Overturning Circulation stopping would seem to be a good reason to suspect the onset of a new ice age. Is that what has been happening repeatedly over the last few million years? Will more CO2 in the atmosphere change this cycle - and if so, in what ways?

Humans will suffer no matter how the climate and sea level and rainfall patterns change, because we have so much expensive infrastructure built around the existing conditions, and such a high global population that there is no room to just move to a better place when one place becomes less hospitable while others become more hospitable.

But, my expectation is that we will see some pretty massive changes, no matter what we do. Even without contributions from human activities, sea levels have reached higher values in the previous interglacial periods - 25 feet higher than today about 120,000 years ago, and even higher in prior interglacial periods. We need to expect sea level to rise, and rise a lot. The only question is how fast, and how high. And, I have read that the Gulf Stream stopping would raise sea level by about 5 feet where I live, which would make my own home flood on every high tide. This article seems to say that could happen fast enough that a lot of people on the east coast of the U.S. could be flooded out in the next decade.

It isn't going to rise in salt sea water but in freshening salt freeing fresh waters which will turn to ice masses quickly unlike the salt seas. It is the more salt free -- though not salt free as such -- freshening waters that will block up the warm Atlantic current and roll pretty fast into the next fresh water 'Ice Age'. The almost cosmic 'colding' of the Earth over millions of years has become the norm of Earth with only lucky interludes of global warming due to our salt seas and, to some degree, tectonic plate movements. The salty oceans only turning slowly back to salty oceans melting the blockage of the Atlantic current flow enough to re-begin global warming. And there are other things, other possibilities including cosmic possibilities from outside Earth, for life on Earth to worry about during the 80,000 to 120,000 years of a real 'Ice Age' (not a 500 year long 'Little (half an...) Ice Age').