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Planet At Risk of Heading Towards Irreversible 'Hothouse Earth' State (vice.com)
An anonymous reader quotes a report from Motherboard: What we do in the next 10-20 years will determine whether our planet remains hospitable to human life or slides down an irreversible path to what scientists in a major new study call "Hothouse Earth" conditions. Hothouse Earth is an apocalyptic nightmare where the global average temperatures is 4 to 5 degrees Celsius higher (with regions like the Arctic averaging 10 degrees C higher) than today, according to the study, "Trajectories of the Earth System in the Anthropocene," published Monday in the Proceedings of the National Academy of Sciences. Sea levels would eventually be 10-60 meters higher as much of the world's ice melts. In these conditions, large parts of the Earth would be uninhabitable. Cutting carbon emissions to limit climate change to 2 degrees C, as proposed in the Paris climate agreement, won't be enough to avoid a "Hothouse Earth," said co-author Johan Rockstrom, executive director of Stockholm Resilience Centre. The reality is that global temperatures aren't driven by human emissions of carbon alone, says Rockstrom -- natural systems such as forests and oceans also play a major role. If global warming reaches 2 degrees C it could trigger a feedback, or "tipping element," in one or more of our natural systems and drive further warming, Rockstrom told Motherboard. To put that into perspective, the recent heat waves and wildfires are being linked to climate change that has raised the global average temperature 1 degree C. The researchers conclude the study on a more uplifting note, saying: "We have the knowledge and ability to act. This is within our control." There are three main areas of action that need to be taken within the next two decades. "The top priority in the coming decade is to aggressively cut carbon emissions and decarbonize our energy systems as quickly as possible," reports Motherboard. "The second priority is to halt deforestation and conversion of nature areas into agricultural production. Forests and other natural areas currently absorb 25 percent of our carbon emissions and this needs to grow." The third action is "to continue to develop technologies to pull carbon from the atmosphere and safely store it for thousands of years." While this last action can be costly, we're starting to see some companies give it a try. A startup called Climeworks recently inaugurated the first system that captures CO2 from the air and converts the emissions into stone, thus ensuring they don't escape back into the atmosphere for the next millions of years.
https://xkcd.com/1732/
Yeah, I know it's a cartoon and not precise scale but it's pretty blatant at the end of it, bad things are coming.
Combine this, with the recent discussion of methane finally escaping in siberia.
https://www.google.com.au/sear...
It's only a matter of time, we're well past the point of no return. I can't really fathom a good analogy, perhaps the titanic? Except 10,000 times larger and moving much, much slower but we're only 6 feet from the ice burg. We're gonna take a little bit to hit it, but rest assured we absoloutely will be hitting that ice burg.
Don't breed, having kids in the future that's coming is only more depressing.
That's because a lot of those countries simply export their carbon emissions; that is, they switch to domestic industries like service industries that are low carbon and simply move production of carbon intensive goods to other countries. The US is so large and diverse that that's not an option.
In any case, in terms of energy intensity, the US is comparable to Sweden, Belgium, and Australia and about world average; in terms of carbon intensity, the US is far below world average. Calling the US a "carbon pig" given those facts makes little sense.
California is burning down. Houston and New York have both been hit by historic hurricanes in the last couple of years. Parts of Florida are already being overrun with rising oceans. Yet I still see a page of denialists right here, let alone bought and paid for Republicans. We're screwed.
I'm a meteorologist but I've listened to enough geology and paleontology seminars to have a basic understanding of the climatic conditions many millions of years ago. You're correct that carbon dioxide levels have been substantially higher than in the present day and that life flourished under such conditions. The Earth has transitioned between two primary states, an icehouse state and a hothouse state. You can think of these as two equilibrium points in Earth's climate about which there are small oscillations. Displace the climate a bit from one of those equilibrium points and it tends to return back. It's much harder to push the climate to the other equilibrium point because a much larger displacement from the current equilibrium is required.
We're currently in an icehouse Earth, with long periods of glaciation and some brief interglacial periods. We're in one of those interglacial periods right now. Releasing enough greenhouse gases into the atmosphere and triggering other feedbacks in the climate system might push the Earth to the other equilibrium point. Such a transition might, indeed, be permanent due to the shifting habitable zone on geologic time scales.
I see two potential problems with this. One is that while the hothouse Earth might be conducive to supporting human civilization as it presently exists. The second is that such an abrupt transition period would be incredibly stressful for life in general. We're not currently seeing mass extinctions, but such a severe transition in climate could certainly trigger such an extinction. It seems likely that Earth would recover and life would thrive again in a hothouse Earth. However, in the previous mass extinctions, the recovery has been somewhere in the range of 2-10 million years depending on the severity of the event. The Permian-Triassic extinction came close to wiping out life on Earth and it's not entirely clear what caused this mass extinction.
We humans depend on the ecosystem beneath us to support human life. I don't believe anyone really knows where tipping points are. There's limited geologic evidence of many past transitions and mass extinctions like the aforementioned Permian-Triassic extinction. Even a less severe extinction event would have massive consequences for humanity. We don't really know what it takes to trigger a mass extinction event, but the geologic evidence we do have says it's something we dare not mess with. While I said it's likely life would recover, there's no guarantee it would include us.
We're not seeing mass extinctions and we don't really know what it would take to trigger such an event. Life can certainly thrive on a hothouse Earth, but that's little consolation if humans don't survive the transition. And mass extinctions aren't very kind to apex predators like what humans are.
... the more plausible scenario. The reverse albedo effect is already taking effect and we're still adding to the carbon circle big time. Trumpistan and the wider world is still blissfully unaware of what's happening, as are the idiots here in my country dragging their heels with solar and driving ever larger luxury Audi's and Porsches and Daimlers, each and everybody on his own, at the same time.
The current heatwave in Germany beats everything we've seen so far. It feels like I'm on the equator. Today they forecast 37ÂC, the highest temperature yet in my region and it's only going to get worse.
We suffer more in our imagination than in reality. - Seneca
China has a very low birthrate - well under replacement. India, in the last couple years, has become sub-replacement. Mexico is essentially at replacement. So I don't know which "high birthrate" countries you're talking about. Essentially the only countries with high growth populations are in sub-Saharan Africa plus a handful of poor oddballs around the world (Pakistan being the largest of these).
source - note that world average replacement fertility is 2.3, lower in rich countries, higher in poor ones.
.... really look at that shit. Its fucking nuts. It can't be sustainable.
....
That map is an illusion. Those ship markers are large in proportion to the size of the oceans and land masses, but in reality the craft they represent are extremely small in proportion. Cross an ocean in a sail boat for 3,000 nautical miles and you'd be lucky to see more than two or three other vessels during the whole trip, even while in shipping lanes.
There is a similar map showing the location of most aircraft around the world. Zoom out the Flightradar24 map to show the entire world and the aircraft markers cover landmasses completely, yet very few aircraft collide and fall out of the sky.
Don't let your Marxist theology carry you away. The sky is not falling.
Running with Linux for over 20 years!