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Antarctic CO2 Hit 400 PPM for First Time in 4M Years

scientificamerican.com

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Re: Antarctic CO2 Hit 400 PPM for First Time in 4M Years

#61

Post by nkurz »

Turing_Machine wrote: post #29
Turing_Machine wrote: post #25

Earlier quoted context omitted.

Okay, I'm all ears (or, technically, eyes, since I'm reading this). How does a 400,000 year old ice core show anything about conditions 4 million years ago? Please be specific.

Now I see mention of an 800,000 year old core in that article. That's still not 4 million, or anything like it.

I was initially dubious of the "4 million year" quote, but the quick searching I did doesn't turn up anything credible that would contradict it, and did turn up many estimates that concur.

I don't know enough to evaluate his methods, but Mark Pagani at Yale seems to have published a number of papers that give estimates going back 40 million years: http://people.earth.yale.edu/cenozoic-evolution-carbon-dioxi...

And this paper 2005 paper by Dana Royer provides an overview of a few hundred estimates going back 500 million years: http://droyer.web.wesleyan.edu/PhanCO2(GCA).pdf

Re: Antarctic CO2 Hit 400 PPM for First Time in 4M Years

#62

Post by josho »

willholloway wrote: post #55
lisper wrote: post #52

Earlier quoted context omitted.

> Am I reading the visualization right that CO2 practically disappears every summer? No. The concentration does drop seasonally, but not even close to zero. See: http://www.esrl.noaa.gov/gmd/ccgg/trends/ Click on the "full record" tab and note that the Y axis starts at 320 (compared to the preindustrial level of 270). The seasonal drop is about 5PPM, and we're at about 400 now, roughly 50% over pre-industrial levels.…

We can fix this, we can take the carbon out of the atmosphere [1]. There is reason for optimism. We. Are. Not. Doomed. The optimum level of carbon is probably slightly above pre-industrial levels. We definitely need to get back below 350ppm to keep human civilization... civilized. 400ppm+ is a trajectory to anarchy. The chimpanzee raiding impulse is alive and well in our DNA, a survival adaptation for stagnation and…

Yup that's all true. But when the next president of the largest economy either doesn't believe in climate change or wants to increase fracking then we clearly have a long way to go before change happens.

Re: Antarctic CO2 Hit 400 PPM for First Time in 4M Years

#63

Post by johncolanduoni »

ageofwant wrote: post #44
danieltillett wrote: post #16

Earlier quoted context omitted.

Relying on natural processes yes there is a problem, but if we were to put WWII levels of resources into it we could create artificial trees [1] while hiding under a short term SO2 umbrella [2]. Of course I doubt we will actually do this. 1. https://en.m.wikipedia.org/wiki/Carbon_dioxide_removal 2. https://en.m.wikipedia.org/wiki/Climate_engineering

Of all these I believe ocean iron seeding to be the most interesting and viable. It may also improve fish stock and have other direct economic benefits. The negative knee-jerk reaction of my fellow Greens on this matter is is only topped by our anti-nuclear power rhetoric. Global adoption of LFTR reactors combined with the massive reduction in coal/oil power plants, ocean iron seeding and the adoption of electric veh…

> Global adoption of LFTR reactors ... if we start today

I'm a huge fan of gen IV reactors in general and LFTR in particular, but we are a long way from being able to deploy any MSRs, even if everyone woke up tomorrow and suddenly took the construction of LFTRs as a terminal moral value. All that have been created to date are small research reactors, mostly 40+ years ago. Almost all of the MSR research projects started recently have fizzled out; AFAIK the only project that has any kind of plan for future civilian nuclear energy is China's. The current regulatory and public opinion environment for civil reactors is absolutely abysmal, and that will likely take even longer to change than the research will.

Re: Antarctic CO2 Hit 400 PPM for First Time in 4M Years

#64

Post by mirimir »

50CNT wrote: post #59
willholloway wrote: post #55

Earlier quoted context omitted.

We can fix this, we can take the carbon out of the atmosphere [1]. There is reason for optimism. We. Are. Not. Doomed. The optimum level of carbon is probably slightly above pre-industrial levels. We definitely need to get back below 350ppm to keep human civilization... civilized. 400ppm+ is a trajectory to anarchy. The chimpanzee raiding impulse is alive and well in our DNA, a survival adaptation for stagnation and…

Why not just massive flywheels? What's the benefit of having a train go over tracks instead of having a large solid wheel?

Maybe bearing scale-up issues?

Re: Antarctic CO2 Hit 400 PPM for First Time in 4M Years

#65

Post by mirimir »

mturmon wrote: post #45
engi_nerd wrote: post #31

Earlier quoted context omitted.

OCO didn't blow up on launch. The payload fairing failed to separate. The vehicle couldn't reach orbit. Doesn't really impact what you're saying (nor does it alleviate the massive embarrassment of Orbital Sciences).

Sloppy of me! You're right, of course. I knew people who went to see the launch at Vandenberg, and (being on the science team) they were crushed [edited to clarify: metaphorically! -- having spent so much hard work in preparation for eventual results] just a few minutes after launch, so I put it into the wrong mental category.

"crushed"?

Re: Antarctic CO2 Hit 400 PPM for First Time in 4M Years

#66

Post by sandworm101 »

lisper wrote: post #52
andrewstuart2 wrote: post #48

Earlier quoted context omitted.

Am I reading the visualization right that CO2 practically disappears every summer? Wouldn't it logically follow then that we're not actually too late to fix our CO2 levels? If we can reduce emissions, plant consumption during the summer months for the northern hemisphere appears to be incredibly effective at basically demolishing the built-up CO2. Or is the "too late" aspect more about the melting polar caps, and tha…

> Am I reading the visualization right that CO2 practically disappears every summer? No. The concentration does drop seasonally, but not even close to zero. See: http://www.esrl.noaa.gov/gmd/ccgg/trends/ Click on the "full record" tab and note that the Y axis starts at 320 (compared to the preindustrial level of 270). The seasonal drop is about 5PPM, and we're at about 400 now, roughly 50% over pre-industrial levels.…

Short answer: There are more trees and other green stuff in the northern hemisphere. As the planet tilts relative to the sun the north/south get more of the light and warmth that helps plants grow. So there is a seasonal up and down to CO2 levels. It's been around for millions of years. What is new is the increased average.

Re: Antarctic CO2 Hit 400 PPM for First Time in 4M Years

#67

Post by mirimir »

lkrubner wrote: post #4
lossolo wrote: post #2

The worst thing is that we can't stop it when it will be too late. This doesn't work like a switch. Even if we would drastically cut all CO2 emission those levels would not drop in our lifetimes.

Indeed. The Earth is large and difficult to steer.

But that is what's mind-boggling. That one species has managed such global impact.

Re: Antarctic CO2 Hit 400 PPM for First Time in 4M Years

#69

Post by opo »

willholloway wrote: post #55
lisper wrote: post #52

Earlier quoted context omitted.

> Am I reading the visualization right that CO2 practically disappears every summer? No. The concentration does drop seasonally, but not even close to zero. See: http://www.esrl.noaa.gov/gmd/ccgg/trends/ Click on the "full record" tab and note that the Y axis starts at 320 (compared to the preindustrial level of 270). The seasonal drop is about 5PPM, and we're at about 400 now, roughly 50% over pre-industrial levels.…

We can fix this, we can take the carbon out of the atmosphere [1]. There is reason for optimism. We. Are. Not. Doomed. The optimum level of carbon is probably slightly above pre-industrial levels. We definitely need to get back below 350ppm to keep human civilization... civilized. 400ppm+ is a trajectory to anarchy. The chimpanzee raiding impulse is alive and well in our DNA, a survival adaptation for stagnation and…

>...Energy storage is possible.

Possible, but except for pumped hydro, it looks like still a lot of work needs to be done.

>...3) Fusion is attainable in the time frame we need it in, if we increase research funding, but its not required. That said if we cracked fusion, we would have all the energy we would need to desalinate seawater and sequester carbon.

I am not sure if fusion is attainable in the time frame needed or it would be economically viable in that timeframe. With fission we have working reactors right now and with a little more research effort we could soon have 4th generation reactors. With reactor designs like the integral fast reactor (https://en.wikipedia.org/wiki/Integral_fast_reactor) there would be enough potential electrical generating capacity to last the world thousands of years. (Of course we should also keep investing in fusion research and energy storage.)

Re: Antarctic CO2 Hit 400 PPM for First Time in 4M Years

#70

Post by yongjik »

tim333 wrote: post #43
nxzero wrote: post #37

Earlier quoted context omitted.

Question is if humanity would have been able to survive for the duration of those 4m years; Earth surviving humanity to my knowledge has never been the issue.

Well, our ancestors were around. It seems it was about 2C hotter from 10 to 4m years ago https://en.wikipedia.org/wiki/File:All_palaeotemps.svg

We don't know what happened to our ancestors. Anything from environmental disasters to epidemics could have wiped out 95% of our ancestors at some time, and the only trace of that would be slightly lower fossil counts.

In other words, "our ancestors survived" isn't really reassuring. There's a really wide gap between "Everybody's lives become seriously harder" and "Humanity goes extinct".

After all, even WW2 only managed to kill ~3% of the human population. A completely survivable event.

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