Researchers Say the Worst Climate Future is Less Likely. But the Best One is Also Slipping Away (apnews.com) 36
Citing new research, the Associated Press reports that "modest gains in the fight to curb climate change have dialed back the most catastrophic of future heating."
That's the good news. But the same research "also confirmed that there's no chance to limit warming to the international goal set in 2015." Researchers' new list of seven plausible carbon pollution scenarios for the future are pushing aside two staples of climate policy: the extremes on either end. The extremes have become less probable in the past several years because of how we power our world. Carbon dioxide, released from the burning of gas, oil and coal, is chiefly responsible for warming. Increasing use of green energies, like solar, wind and geothermal, which don't emit carbon dioxide, have lowered top end carbon pollution projections. However, because those changes haven't been fast enough, the bottom end projections have risen.
The Paris climate agreement in 2015 set a goal of limiting warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) since pre-industrial times, or the mid-1800s, giving rise to the mantra "1.5 to stay alive," but now scientists say that even their best case scenario still shoots past that signature temperature mark. On the other end, those same new scenarios no longer include the coal-heavy future that would lead to 4.5 degrees Celsius (8.1 degrees Fahrenheit) of warming by 2100, a scary scenario that many scientific studies used in their future projections.
The new proposed worst case scenario has an end-of-the-century warming of about 3.5 degrees Celsius (6.3 degrees Fahrenheit), a full degree (1.8 degrees Fahrenheit) less than the old scenario, while the updated best case future is a couple tenths of a degree Celsius (0.36 degrees Fahrenheit) warmer than previously theorized, squeezing past the Paris goal, said climate scientist Detlef Van Vuuren of Utrecht University, lead author of a recent study laying out future scenarios. "There is kind of a narrowing of the futures. It cannot be as bad as we thought, but it cannot be as good as we hoped," said Johan Rockström, director of the Potsdam Institute for Climate Impact Research in Germany.
The scenarios include a "middle" one where by the end of the century the world warms 3 degrees Celsius (5.4 degrees Fahrenheit) above pre-industrial times, which is roughly the path society is currently on, scientists said... Because carbon pollution keeps rising globally and stays in the atmosphere for about century, the best case scenario is for warming to shoot past the 1.5 degree mark, peak at 1.7 degrees Celsius (3.1 degrees Fahrenheit) for maybe as long as 70 years, and eventually somehow come back down below 1.5 degrees if a technology can be designed to remove massive amounts of carbon from the air, said nine of the 10 scientists interviewed for this article. The world is warming at a pace of a tenth of a degree Celsius (nearly 0.2 degrees Fahrenheit) every five years, they said.
That's the good news. But the same research "also confirmed that there's no chance to limit warming to the international goal set in 2015." Researchers' new list of seven plausible carbon pollution scenarios for the future are pushing aside two staples of climate policy: the extremes on either end. The extremes have become less probable in the past several years because of how we power our world. Carbon dioxide, released from the burning of gas, oil and coal, is chiefly responsible for warming. Increasing use of green energies, like solar, wind and geothermal, which don't emit carbon dioxide, have lowered top end carbon pollution projections. However, because those changes haven't been fast enough, the bottom end projections have risen.
The Paris climate agreement in 2015 set a goal of limiting warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) since pre-industrial times, or the mid-1800s, giving rise to the mantra "1.5 to stay alive," but now scientists say that even their best case scenario still shoots past that signature temperature mark. On the other end, those same new scenarios no longer include the coal-heavy future that would lead to 4.5 degrees Celsius (8.1 degrees Fahrenheit) of warming by 2100, a scary scenario that many scientific studies used in their future projections.
The new proposed worst case scenario has an end-of-the-century warming of about 3.5 degrees Celsius (6.3 degrees Fahrenheit), a full degree (1.8 degrees Fahrenheit) less than the old scenario, while the updated best case future is a couple tenths of a degree Celsius (0.36 degrees Fahrenheit) warmer than previously theorized, squeezing past the Paris goal, said climate scientist Detlef Van Vuuren of Utrecht University, lead author of a recent study laying out future scenarios. "There is kind of a narrowing of the futures. It cannot be as bad as we thought, but it cannot be as good as we hoped," said Johan Rockström, director of the Potsdam Institute for Climate Impact Research in Germany.
The scenarios include a "middle" one where by the end of the century the world warms 3 degrees Celsius (5.4 degrees Fahrenheit) above pre-industrial times, which is roughly the path society is currently on, scientists said... Because carbon pollution keeps rising globally and stays in the atmosphere for about century, the best case scenario is for warming to shoot past the 1.5 degree mark, peak at 1.7 degrees Celsius (3.1 degrees Fahrenheit) for maybe as long as 70 years, and eventually somehow come back down below 1.5 degrees if a technology can be designed to remove massive amounts of carbon from the air, said nine of the 10 scientists interviewed for this article. The world is warming at a pace of a tenth of a degree Celsius (nearly 0.2 degrees Fahrenheit) every five years, they said.
Give the magatards a chance (Score:4, Insightful)
Re: (Score:2)
And data centers, don't forget data centers.
Re: (Score:2)
Nuclear is just around the corner. Particularly for data centers and AI. Cost is no object, so the "Reeee! Nucular is expensive!" doesn't matter.
Re: (Score:2)
Nuclear is just around the corner. Particularly for data centers and AI. Cost is no object, so the "Reeee! Nucular is expensive!" doesn't matter.
Should Google Go Nuclear? [youtube.com]
I'm sure they invited other guest speakers besides the late Dr. Bussard, but that's the link I have bookmarked from nearly two decades ago. It just shows that the people with the really big data centres have been thinking about building their own nuclear power stations for quite some time.
I still think it's a shame that Polywell never amounted to anything but the talk is still interesting because Dr. Bussard also covers a few things that we could accomplish with cheap, plentiful f
Re: The climate grift (Score:5, Informative)
Re: (Score:1)
Always funny when the deniers turn out to be illiterate...
Re: The climate grift (Score:4, Informative)
Climate latency is around 40 years, so if 2025 is when the climate trajectory passed the point of no return, then the actual prediction is that Miami will be in serious trouble by 2065 and that no viable path to Miami recovering will exist, that CO2 won't drop to levels that permit such a recovery within the remaining lifespan of any part of Miami.
Re: (Score:1)
40 years is much too optimistic. We're dealing with nonlinear phenomena. Things change slowly until they change quickly, and then they're irreversible.
Once we pass the first few major tipping points, the eventual transition of the earth to a hothouse state will be inevitable. When the arctic ice cap disappears, warming will accelerate dramatically. When the Amazon collapses, it will release massive amounts of carbon into the atmosphere. Both of those will accelerate thawing of the permafrost, releasing
Re: The climate grift (Score:1)
Re: (Score:1)
i too can always win arguments when i make up my opponents positions, it's actually super effective! try it in real life!
Re: The climate grift (Score:3)
What we should be doing is recognizing that if the predictions keep pointing the same direction, there's something they're all pointing at. Improving data may change how well we can tell how far away the thing is, and how large it is. But that there is a thing in that direction we should be c
Re: The climate grift (Score:1)
As expected (Score:4, Insightful)
The "worst case scenario" was never likely. Neither was the "best case scenario" likely.
It was always going to be somewhere in the middle.
Life is gonna suck for a whole lot of the world. Humanity will survive. Life will go on. We can still choose just how bad we are going to make it. How many of us survive. How we live. How many other species survive. How many don't.
Re: (Score:3)
Reading the entire article would do you wonders.
Re: (Score:1)
Re: (Score:3)
No they aren't "guesses", and nobody goes by what a single model predicts. That's not the way you use models in this sort of simulation.
Psst (Score:2)
Re: (Score:2)
It could still be that bad (Score:4)
The article includes a major qualification that was omitted from the Slashdot summary:
While the upward curve of emissions is flattening, there's a factor that could still make the older high end temperature estimates come true, Mahowald, Rockstrom and Hare said. That's because the newest batch of scenarios only look at emissions from the burning of fossil fuels, which is the control knob that humans can turn.
Nature has another knob of its own referred to as climate feedbacks, which humans don't control. Scientists have had a hard time projecting climate feedbacks, and that can add another half a degree Celsius (nearly a degree Fahrenheit) of warming on top of what's caused by emissions.
Those feedbacks include release of massive amounts of heat-trapping carbon now being stored in the world's oceans, in forested areas and in the Amazon, along with changes to ocean currents and cloud reflectivity, Rockstrom said.
The thing they've ruled out is the high end estimate of how much CO2 humans will emit, not how much the planet will warm. The rate of warming has accelerated in recent years, not because of how much we're emitting but because natural feedbacks are starting to amplify it. There's growing evidence that the old warming estimates were too low, and each emissions scenario will produce more warming than we previously thought it would.
Re: (Score:2)
CO2 residence time (Score:1)
Previous critical analyses facing the IPCC's favored interpretation of the carbon cycle and residence time have been published, e.g., by Jaworowski et al. (1992), Segalstad (1998), Dietze (2001), Rörsch et al. (2005) or Essenhigh (2009), and more recently by Humlum et al. (2013), or Salby, 2013, Salby, 2016. Although most of these analyses are based on different observations and methods, they all derive residence times (in some cases also differentiated between turnover and adjustment times) in part se