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Earth Science

Three Years Left To Limit Warming To 1.5C, Leading Scientists Warn 135

An anonymous reader quotes a report from the BBC: The Earth could be doomed to breach the symbolic 1.5C warming limit in as little as three years at current levels of carbon dioxide emissions. That's the stark warning from more than 60 of the world's leading climate scientists in the most up-to-date assessment of the state of global warming. [...] At the beginning of 2020, scientists estimated that humanity could only emit 500 billion more tonnes of carbon dioxide (CO2) -- the most important planet-warming gas -- for a 50% chance of keeping warming to 1.5C. But by the start of 2025 this so-called "carbon budget" had shrunk to 130 billion tonnes, according to the new study.

That reduction is largely due to continued record emissions of CO2 and other planet-warming greenhouse gases like methane, but also improvements in the scientific estimates. If global CO2 emissions stay at their current highs of about 40 billion tonnes a year, 130 billion tonnes gives the world roughly three years until that carbon budget is exhausted. This could commit the world to breaching the target set by the Paris agreement, the researchers say, though the planet would probably not pass 1.5C of human-caused warming until a few years later.

Last year was the first on record when global average air temperatures were more than 1.5C above those of the late 1800s. A single 12-month period isn't considered a breach of the Paris agreement, however, with the record heat of 2024 given an extra boost by natural weather patterns. But human-caused warming was by far the main reason for last year's high temperatures, reaching 1.36C above pre-industrial levels, the researchers estimate. This current rate of warming is about 0.27C per decade -- much faster than anything in the geological record. And if emissions stay high, the planet is on track to reach 1.5C of warming on that metric around the year 2030. After this point, long-term warming could, in theory, be brought back down by sucking large quantities of CO2 back out of the atmosphere. But the authors urge caution on relying on these ambitious technologies serving as a get-out-of-jail card.
"For larger exceedance [of 1.5C], it becomes less likely that removals [of CO2] will perfectly reverse the warming caused by today's emissions," warned Joeri Rogelj, professor of climate science and policy at Imperial College London.

"Reductions in emissions over the next decade can critically change the rate of warming," he added. "Every fraction of warming that we can avoid will result in less harm and less suffering of particularly poor and vulnerable populations and less challenges for our societies to live the lives that we desire."

Three Years Left To Limit Warming To 1.5C, Leading Scientists Warn

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  • locked in (Score:5, Informative)

    by ZipNada ( 10152669 ) on Thursday June 19, 2025 @11:56PM (#65462613)

    Sadly, a considerable amount of additional warming is already locked in.

    "If the large-scale carbon dioxide removal needed to reach net-zero emissions is unfeasible and instead, the remaining hard-to-mitigate emissions approximately balance natural sinks, atmospheric greenhouse gas (GHG) concentrations will remain constant. Such fixed GHG levels will result in continued warming until the climate system reaches a state of radiative balance, which we call “committed warming.”
    https://agupubs.onlinelibrary.... [wiley.com]

    • Re:locked in (Score:5, Interesting)

      by serafean ( 4896143 ) on Friday June 20, 2025 @04:20AM (#65462923)

      > Sadly, a considerable amount of additional warming is already locked in.

      Unfortunately, it seems to be more than we think.
      The energy imbalance is increasing : https://agupubs.onlinelibrary.... [wiley.com]
      Aerosol forcing is reducing due to us reducing pollution. This puts India in an interesting position: clear pollution and heat up, or keep pollution and suffocate.
      Finally the CMIP6 set of models seem to be unable to model the last couple of years, being under reality. https://cicero.oslo.no/en/arti... [cicero.oslo.no]

      1.5C is over, 2C is probably already baked in.

      • by AmiMoJo ( 196126 )

        We should be funding multiple moon-shots to try to deal with this. Apollo-like efforts to remove CO2 from the atmosphere at scale, or find some other way to limit warming.

  • Let's not pretend we are going to try to achieve this. Let's admit we are only doing a bit of damage control.
    Let's continue to fight each other. See who is the strongest. Let's keep competing on who can make the most noise.
    This is what failure looks like. We should have stayed in our caves. ;-)
    • by gweihir ( 88907 )

      This is what failure looks like.

      Indeed. Failure on the level of a whole species. That is special. And no, denial will not fix this, no matter how much a lot of completel morons believe that.

  • Because that is such a good idea.

  • is:

    3 years left to become a world with net zero CO2 and CO2 equivalent emissions.

    3 years to zero Oil, Gas and Coal usage

    3 years to zero meat consumption

    3 years to zero concrete

    When reducing CO2 from fossil carbon usage (that is Oil, Gas and Coal) to net zero only, we may continue with meat and concrete for many many more years.

    Realism? Lost on any of above net zero conditions alone.

    The Question is more: Do you want to be part of the cause? Do you want to have blood on your hands for billion of deaths? Do yo

  • Geoengineering now (Score:4, Insightful)

    by Bruce66423 ( 1678196 ) on Friday June 20, 2025 @03:44AM (#65462899)

    Let's get realistic, people. Humanity is not going to reduce its carbon emissions to what is necessary to prevent serious consequences. The only realistic option is to do some form of geoengineering. It's the least bad solution - because it's the only one that may actually work.

    • by skam240 ( 789197 )

      What you just said.

      Globally speaking warming emissions are still increasing so how does anyone think we're getting to net zero any time soon? Even after we halt the rate of emission increase we still have a truly massive task in front of us to reach net zero and even then we'll still need to wait for the environment to stabilize as even at net zero we'll still have the problem of all the extra CO2 that we put into the environment up until we hit net zero. There's just no way we're going to accomplish all th

      • Well, the transition to electric and solar and in some cases hydrogen is happening pretty rapid at the moment.

        • by skam240 ( 789197 )

          With global emissions still growing, not decreasing, clearly renewables arent growing anywhere near fast enough and that's only dealing with electrical generation. To reach net zero we'll need to solve emissions related problems with many other things like like air travel and concrete production. I would love to be wrong but given all this I don't see how we'll reach net zero before we dont have serious problems that we need to mitigate. Net zero strikes me as a really hard place for us to get to.

    • Just because we are not going to reduce emissions doesn't mean we should continue to pollute as we are doing now. Some countries, especially, have a lot of "fat" to cut (could easily reduce emissions without too much negative effects). Those countries are USA, Australia, Canada, etc. those with very high CO2 emissions per capita.
      And the easiest way to achieve that is by putting a price on carbon. We can argue on what the price should be, but it shouldn't be 0.

      • The problem is that the people are unwilling to do it, and opportunistic political leaders are getting votes by refusing to enforce these policies. Given that, geoengineering is the only realistic hope.

        • Then the "only realistic hope" is more expensive than reducing wasteful CO2 emissions such as shutting down coal plants in the USA, or having people drive less or more fuel efficient vehicles.

          Someone has to pay for geoengineering as well. So if you ask people if they prefer to pay $1000/year in carbon tax or pay $10000/year in geoengineering fees to get the same results, the choice is pretty simple.

          • By the way if SOME geoengineering projects end up being the most efficient way of attenuating global warming, their contributions could be counted towards carbon credits in a properly implemented carbon market.

          • Someone has to pay for geoengineering as well. So if you ask people if they prefer to pay $1000/year in carbon tax or pay $10000/year in geoengineering fees to get the same results, the choice is pretty simple.

            I think you present a false dichotomy. Several of the proposed geoengineering schemes are relatively inexpensive, though of course a lot of investment will be needed to demonstrate their practicality and effectiveness. I expect that geoengineering will be much cheaper than getting to net zero.

            However, that doesn't mean we don't also need to get to net zero, because the geoengineering proposals only address warming, not the other effects of high atmospheric CO2. Ocean acidification and whatever is downst

            • Anyways it doesn't matter. It's not you, I or the gouvernement who should pick whether geoengineering is worth it or not. It's the market.
              Those who emit CO2 increasing the global temperature by 0.00000001C should have to pay the bill to reduce the global temperature by 0.00000001C.

              Now, who can provide the most efficient/cheapest solution to reduce the global temperature by 0.00000001C should be awarded the contract. That person may be shutting down coal plants and replacing them by solar. Or can be doing so

              • I'm also a fan of market solutions. Most people aren't, though, and they're especially challenging with an international problem, so I don't think carbon taxes or warming fees is how we'll do it.
                • which brings me back to the example of paying 10x as much for the same result. This is pretty much what I expect if we choose a non-market solution.
                  Even the so-called "conservatives" in the US and Canada oppose market-solution for the climate/pollution problems. It's almost as if their goal was to maximize pollution.

                  • Most people fundamentally don't believe in markets. Look at how they react when prices rise due to a supply bottleneck or similar. They shout "Greed, we're being gouged!", even when there's plenty of competition to keep prices down and rising prices is actually the optimal solution to suppress demand in the short term and encourage increases in supply in the long term. Conservatives are worse than liberals these days, since conservatism/liberalism has evolved to be divided in large part by education leve

              • It's not. There isn't the political will to introduce a proper carbon tax, as the election of Trump demonstrates. The reality of other companies / countries being able to operate without the carbon tax will always ensure it's going to stay a nice theory. Turkeys don't vote for Christmas, and petrol heads will believe those who argue it's not necessary, because they want to.

  • This sort of thing cannot be allowed to happen, quite outrageous, must be stopped no matter the cost: Flavour of gin and tonic could be impacted by climate change, study finds [theguardian.com].

  • What utter nonsense. Only totally unrealistic scenarios could still limit global warming to 1.5 degrees. As in: we stop using fossil fuels today and stop eating meat today (both would collapse the economy). In reality we have known about this for a long time, starting really talking about it in 1979 and launched IPCC in 1988. We're now 46 years in the future and apart from some hiccups due to COVID and the odd economic/oil crisis, each and every subsequent year we have increased our emissions and destroyed

    • by sinij ( 911942 )

      Humanity and many other species are absolutely fucked.

      Stop hyperventilating. Higher (and lower) temperatures were observed in both geological record and during human history. Greenland had forests, Sahara was green. If something going to wipe humanity, it is probably going to be nukes or engineered virus, not climate warming.

    • Re: (Score:2, Flamebait)

      by Alypius ( 3606369 )
      Typical leftist. "Do what I tell you or St. Luigi (PBUH) will find you." Go take your Stalinist shit back to Russia.
  • Our planet is in a warming cycle, there won't be any pole ice in 50 to 100 years. This is inevitable regardless of what humanity does, save some extreme geoengineering. This is OK and happened many times in our planet history. Enjoy Global Greening [nasa.gov] and stop worrying about Milankovitch cycles [wikipedia.org].
    • The current warming, however, has nothing to do with Milankovitch cycles

      Which would be pretty obvious to you if you at least glanced over the article you linked.

  • Let's be honest with ourselves shall we?

    People are really, really good at lying to themselves first and foremost - it's how we survive day-to-day existence. The majority of us are therefore very susceptible to other people's lies.

    We have been burning dead dinosaurs for far too long and those with a vested interest have known for nearly half a century that what they were doing was going to cause significant damage to the planet.

    The oil companies repeatedly lied to the politicians, their investors and to us.

  • Should be: "Breach of 1.5 C limit inevitable, may happen as soon as three years."

  • I suspect that a lot of really rich and/or important people are going to have to die first before we, as a species, actually DO anything about it. (Black Swan Events not withstanding, of course. If someone could poke a volcano or start a nuclear war it might solve the heating problem but then you get side effects that sound like a pharmaceutical company's disclaimer.) And yes, our children and their children SHOULD hate us for it.

  • Oil and gas are set to run out in around 50 years. Coal, longer, maybe 100 or so. So, which is the more existential problem? That or global warming?
    • Global Climate Change. Loss of fuels when solar and wind are more than enough for substitutes is nothing more than a problem of will.
      Lack of FOOD as well as heat wave induced population crash and migration will destroy civilizations.
  • The problem as I see it is that if we take it read that all of this is 100% absolutely true and we have three years to prevent an existential world-wide crisis from destroying the environment and rendering the Earth as inhospitable, then all eyes should be on China--which thus far has been exempted from various intergovernmental requirements to reduce CO2 emissions. And part of the problem is that while China itself claims it has capped carbon emissions--a lot of the environmental and governmental statistic

"Religion is something left over from the infancy of our intelligence, it will fade away as we adopt reason and science as our guidelines." -- Bertrand Russell

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