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The climate will need just a moment to respond to this massive and shockingly sudden insult before it stabilizes. Before that can fully happen we must first stop emitting warming gases.
We are at the beginning of a highly unstable ultra-rapid human caused climatic shift.
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Sam
Those statements by Sam I bolded are not vindicated by physical facts. There is little cause for such alarmism.
Quite to the contrary. The CO2 in the atmosphere, along with several other key warming gases will take millennia to reduce to prior levels assuming current ecosystem functions. And that only happens if the climate doesn’t shift before that can occur. As the climate shifts, the ecosystems shift, and those basic functions are put at risk.
What should be amply clear (and is) even to young people, let alone to those of us with more life history behind us, is that we are already seeing an ultra rapid shift in progress.
We see that with the rapidly vanishing arctic ice. We see it with the methane boiling out of the clathrates on the arctic plains. We see it with the collapse of the tundra globally. We see it with the warming of the ocean surfaces sufficient to doom coral reefs within the next decade or two. We see it in the hyper rapid acidification of the oceans which doom most shelled creatures. We see it in the very rapid melt on both Greenland and the West Antarctic sheet. We see it in the rapid loss of mountain glaciers and ice all over the world, and with the quite soon loss of the glacial ice supporting a billion people in South Asia. We see it in the destabilization of the atmospheric circulation with massive swings in heat transport both north and south from and to the arctic resulting in climatic chaos in the northern hemisphere beginning. We see it in droughts, fires, deluges and worse. .... and in a thousand other ways ....
Hefaistos, that you apparently choose not see these and myriad indicators is only evidence of your own willful and reckless blindness.
Greta Thunberg is still a young person. Yet she sees clearly, where you do not. She sees the indicators and clearly and concisely called out the leaders of the world in Davos. She is right. You are wrong.
Yes the oceans will take time to equilibrate. And perhaps if we bend every effort, destroying civilization as we know it in the process, we might now barely be able to salvage something of the world we know. Personally, I doubt that is possible any longer. We waited too long. We were too slow to learn. We were and remain too blind to see. And the CO2 trends from Mauna Loa speak volumes to that at megaphone levels. We are not in any way doing what must be done. Instead we argue about slowing the rate of increase of the rate of increase. That is insane.
Worse leaders of major countries are already throwing out efforts to reduce emissions and are instead increasing the rate of burning of oil, coal and natural gas, while also slash burning the lungs of the world. That is beyond insane.
The CO2 already in the atmosphere is catastrophically high. Under the most optimistic business near usual trends, we don’t even slow the increase, let alone stop it, and reverse it. Under these conditions, we will release the 1,600 Gigatons of carbon in the permafrost. And we will boil out the clathrate on the arctic plains, both in the very near future. Either of those take the situation completely out of human control.
Yes the oceans will take time to equilibrate. The continued heat input caused by the warming gases will assure that there is heat enough and time enough to do that. But that is meaningless in the time scale of the catastrophe we face. The continued heating of the Earth from the gases in the atmosphere will assure it. And the changes in the surface biosphere and atmosphere will not wait for that equilibration to finish.
Our rate of change now makes the PETM look obscenely slow. And yet the PETM is the definition of rapid climate change. We are now in the early stages of an ultra rapid climate shift. And that is obvious for all to see except for the willfully blind.
In time, the Earth may shift back to this mostly precariously stable point between hot house and ice house conditions. These have been rare in Earth’s history. The orbital balances could bring us back to some stable place with ice remaining in the Antarctic. And perhaps in half a million years there may be ice in the arctic again. But it is also possible that we continue on a runaway to hot house conditions, having pushed over the climate and ruined the world we know.
I worry more about the highly unstable transition. Creatures can adapt to hundred millennia scale changes. Decade scale changes are another matter entirely. Worse, the impacts of the collapse of whole ecosystems may have dramatically more important transient impacts on O2, pressure, temperature, rainfall, circulation, CO2, methane and other parameters that may drive many species and even whole genera extinct.
Sam