Possibility for strong high-latitude cooling under negative emissions
nature.com
nature.com
We don’t normatively need the atmosphere to be “natural,” we just need it to be in a state that doesn’t destroy the thousands of years of infrastructure we’ve built.
In order to hit the "brief and rapidly closing window" we have for effective action, we need to look into lowering material flows and energy use by targeting overconsumption. We simply don't have time to wait for a tech miracle, and – as this study points out – the miracle can have huge downsides.
Whatever the topic, I mentally ignore posts which shill the NEXT WORST THING EVER.
Most of the waiting scenarios involve a drastic decrease in farmland for the US/Europe and larger gains in Canada / Russia.
The planet quite frankly doesn’t care if NY / LA / London lose 6 to 12 Ft of land. Even if no one moved and everyone just stayed there to drown, humanity still goes on.
The whole thing mostly fixes itself anyway once population peaks in a few decades. It’s not global warming that kills humanity, it’s our population eventually reaching zero through sub replacement birth rates tho maybe there is a saving grace where once incomes get high enough it rebounds.
I am not so arrogant as to think without humans the planet dies. But maybe unlike most Americans I don't want to sacrifice my grandparents so that people can dine in person at Applebee's, nor do I want to live in a worse, less human-friendly world so that oil executives can make another few decades of profit.
We can decarbonize with the technology we have today. We know it will be more expensive economically to wait until it's too late, but it'll be more expensive for taxpayers instead of maybe the companies doing so well they can spend millions on lobbying every year.
Farming isn't really the issue, we can eke out 10x the calories by cutting pork/chicken/beef. Wet bulb temperatures (where you can't cool off by sweating and die cooked inside out) are a larger issue. Tons of other cycles that we're fucking with besides carbon, like nitrogen and phosphorus. We're also losing arable land to desertification. I don't even have to get started on our available freshwater reserves.
To think humanity will just kinda coast by and that it will all mostly fix itself must be a very nice thought, but it flies in the face of what every single person we pay to study this is saying. And they're not saying humans go extinct.
Per the ipcc model, if we could wave a magic wand and have zero emissions tomorrow, CO2 levels would fall faster than they have been increasing.
We already have free CO2 removal. The challenge is and always has been on the emission side.
CO2 levels are about 420 ppm and go up about 1.5 per year. A 120 year half life yields -3.5 ppm per year.
It is worth investing some money in development for the moonshot possibility of economic viability. Unless it becomes cheaper to capture than build renewables, the the money will always be better spent on green energy.
Anything useful you could make out of CO2 can be made much easier from fossil fuels.
Traditionally, the idea is that the ocean would absorb the 'excess' CO2 put there by fossil fuel combustion over the industrial era. However, this is quite a slow process and it's entirely possible to reach a new steady state of relatively high atmospheric CO2 (and high global temperature, i.e. ice-free poles) and stay there for several million years - it's happened in the past. Furthermore, we have the permafrost melt ongoing across the Arctic, and shallow marine sediments are also releasing methane and CO2. This will continue for decades in the immediate zero-emission scenario, that turning point has come and gone.
Maybe if a full transition off fossil fuels had begun in 1980, when the science was clear, we'd be stabilizing at current conditions (*it takes ~100 years for the climate system to finish responding to current forcing, assuming no additional forcing, mainly due to oceanic warming lag effects). We're in for warming for the next 50 years, no matter what, and the world is clearly not getting off fossil fuels any time soon, all the major fossil fuel actors have plans for status quo production for the next 30 years (rather than say 3% reduction per year, which would mean no fossil fuel production in 30 years).
It's going to happen slowly on human time scales, i.e. the scale is decadal for noticeable differences in the year-to-year average, but it's also inexorable. "It's in the post" is the British saying that applies. Like trying to throw the rudder over on the Titanic after the iceberg is detected, it's all too little too late.
If you can prevent X tons of co2 for $y dollars , it is better than capturing X tons. for $>y dollars.
It only makes sense to capture co2 if you have already prevented everything you can.
Yes it would have been better to start in the 80s, but that doesn't change the math today or tomorrow.
If the carbon cycle changes, it will still be better to stop emissions than capture.
> It only makes sense to capture co2 if you have already prevented everything you can.
Like I said in another thread, it’s this kind of stuff that makes net zero never happen as many people, like yourself, are inherently opposed to CO2 emissions.
A girl can dream.
- ed: I am fascinated by the idea that otherwise horrid floating plastic pollution can act as centres for bio-accumlation leading to local, floating bio-domains. I guess the real problem is plastic bags and fishing nets, not toothbrushes that happen to float.
Look at the situation in Germany where CO2 emitting Russian oil and gas was preferable by the Greens to zero CO2 nuclear.
Net zero CO2 is the ultimate bike shedding issue, because it’s so easy a child could solve it, it devolves into endless bickering.
Keeping our current emissions will keep increasing that excess of CO2 and GHG, getting to some sort of net-zero (not the proposed one in COP26, but one counting with all kind of mankind carbon emissions AND the one emitted by the current already triggered feedback loops) will keep more or less the same amount of GHG in the atmosphere as CO2 lasts there for centuries.
The only way to have some hope that things don't keep getting worse is to manage to do negative emissions, and bring GHG down to pre-industrial levels, or even lower, if we want to drop in some way the global temperature average that had been steady rising for many decades, as that extra temperature is fueling positive feedback loops.
If there is a shortcut for making that temperature drop, because natural processes like the AMOC or whatever, the better, because we are not fighting for how livable will be a particular region of the world, but the entire world.
(I saw a PBS special on this part in the 90's. Recent satellite data strongly suggest this is already happening. The last time this happened, Europe went from "too hot" to "glacier" in the under fifty years.
If we wait for that to happen, then cool the atmosphere, then it'll make the coming ice age worse in the short term.
In other decades-old news, if we don't start capturing CO2 after that, and the predictions about runaway greenhouse gas mechanisms are true, Earth will become like Venus, obliterating life on earth.
Am I the only one that learned about this from watching PBS in the 90s? Is there something novel in the paper? It's good to raise awareness of just how f-cked we are, I guess.
I'm also confident that the root cause of the crunching noise and vibrations from the front end of my car will eventually lead to a breakdown, but I don't have any idea if it'll happen tomorrow or in a year.
Either way, we're talking about either abandoning most of Europe in our (or our children's) lifetimes, or just using existing technologies to avoid that, along with many other disasters.
Concretely, the magnitude of our current predicament was correctly forecast by computer models well before 1980, and the basic mechanisms and effects those models were based on were well-established by the 1960s.
Claims to the contrary have been extensively documented to be part of a paid misinformation campaign the fossil fuel industry ramped up in the early 1980s.
The show wasn't particularly sensationalist, for what its worth. Climate change was a bipartisan concern back then, and it mostly focused on the fossil records that backed up the claims it made. It also talked about the solar cycle's impact on earth's average temperature and compared the magnitude of the effects over time.
All the technology that was needed to head off disaster was already commercialized, assuming a one-two punch, where phase two involved better batteries.
No one imagined we would choose to take no action for another 30 years.
If I had to bet what actor would be president in 2016, I'd have guessed Patrick Stewart, and that his second move (after installing the captain's chair in the oval office) would be pointing at a clean energy plan to replace our carbon nuclear fission power grid with fusion / solar and saying "make it so".
So what? There are false climate predictions from back then too, and nobody knew which ones would turn out to be true or false. It was an immature field and predictions were all over the place, including global cooling.
If I produce a dissenting climate prediction, will you produce evidence that that specific piece of research was both paid for by the fossil fuel industry and known to be false by the general climatologist community?
The rapid change in environments can make many species no longer suitable for their environment leading to extinction. Sometimes they can transfer to a new environment, or sustain at a degraded efficiency, but often they cannot if the environment change is drastic enough. This is happening everywhere all at once.
It's the same principle as what makes a battery fire so destructive - all of the energy stored in the battery in a plant somewhere else suddenly gets discharged all at once in your car.
As to the larger point, the sun was ~30% dimmer 4.5 billion years ago and will get about 67% brighter over the next 4.7 billion years. While we would be dead long before we could free up all the worlds trapped carbon, in such a hypothetical situation the world isn’t simply returning to an earlier state.
I'll trust those over a PBS special from the 1900s.
Global warming and CO2 rise are such difficult problems, and we put so much focus there, it makes me really glad to see some people taking a broad view.
That difference is the eradication of much of life on earth that is unable to evolve to a new environment. For example, insect numbers worldwide are drastically lower than decades ago, and insects are required for almost all pollination of plants and a key source of food for small animals. The "food chain" collapses if there is no first chain.
Even a partial loss of ecodiversity can lead to further problems later.
Our efforts are certainly not in vain.
It seems to me that at some point we could just wrap the earth in shutters(since we're talking far future anyway) or intentionally release greenhouse gasses to servo the planet's temp.
* - I believe much of the geothermal heat is actually heat from fission already so I don't know if fission energy changes the balance much.
On what basis do you believe this?
https://www.psu.edu/news/research/story/probing-question-wha...
H2O is by far the most significant GHG; compared to it, CO2 is a rounding error.
These forecasts used to be 4.5C or more. Now the forecasts are 1.5C and yet the IPCC is still pushing hard.
It happens that the average tropospheric temperature increase over the last 40 years of satellite measurements is 0.13C per decade, or 1.3C per century if that rate continues.[0] We have still not peaked during this interglacial epoch, but the tropospheric warming appears normal and less than the IPCC target.
[0] https://www.drroyspencer.com/2022/03/uah-global-temperature-...
According to NASA [1], that is false.
[1] https://climate.nasa.gov/ask-nasa-climate/2953/there-is-no-i...