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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

#31

Post by engi_nerd »

mturmon wrote: post #26
benjoffe wrote: post #21

Earlier quoted context omitted.

Not entirely sure, but could be using the data from the Orbiting Carbon Observatory satellite[0]. This satellite orbits the Earth on the order of ~16 times per day which would not be enough granularity for the smoothness of this video, so I assume it's been combined with other weather data and advanced modelling to provide the smooth interpolation. [0] https://en.wikipedia.org/wiki/Orbiting_Carbon_Observatory

OCO blew up on launch, but OCO-2, its successor, has been producing data since 2014. This nature run was from 2006, which predates the OCO-2 era, and predates GOSAT, another CO2 satellite. It may overlap partly with SCIAMACHY, an ESA mission. But in summary, I don't think the video was heavily constrained by actual CO2 observations, which are done only at a small number of sites on the ground (TCCON or FTIR). The vid…

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).

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

#32

Post by tim333 »

danieltillett wrote: post #19
hyperbovine wrote: post #17

Earlier quoted context omitted.

I have no doubt at we will try this, plus a lot of even dumber ideas, once the shit really starts to hit the fan. The world is not going to just sit back as Manhattan, Mumbai, Shanghai, Sydney, Rio, etc. disappear under a foot or two of water. Politicians (the same one who spent 50 years failing on this issue) will demand action. It's the best argument I can think of for putting serious research effort into geoengine…

Artificial trees are not considered geoengineering since they are just reversing the CO2 released. The really sad aspect is we are not putting in the R&D resources needed to develop them to the required scale. No matter what we do about preventing the release of more CO2, we need to deal with the CO2 that has already been released.

Regular trees work quite well and are cheaper. You just have to harvest them and not burn the wood, or turn it to biochar.

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

#33

Post by tstactplsignore »

Turing_Machine wrote: post #25
wolfram74 wrote: post #9

No no, that just won't do. Math and modeling doesn't allow us to draw conclusions about things we can't directly observe. Someone had to be there and directly count the co2 molecules with their own eyes or it doesn't count as evidence.

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.

There are specific mineral records that covary strongly with CO2 levels over that 400,000 year period. However, these mineral records go back millions of years - therefore, we can use the known relationship to predict how CO2 levels have changed in the past. These are known as "proxies" in paleoclimatology, and can be used to estimate past CO2 levels, O2 levels, temperature, and other attributes of Earth's climate. When multiple independent proxy estimates agree with each other, we can somewhat safely assume we are not too off-target. This field is constantly getting updated, but these proxies are usually in decently good agreement with each other. I think that the paper below is a good overview of the science involved. I'm not an expert in the field but this paper is from 2006 and likely now the field has added some more accurate proxy paleo-CO2 reconstructions.

http://droyer.web.wesleyan.edu/PhanCO2%28GCA%29.pdf

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

#34

Post by chc »

Turing_Machine wrote: post #27
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.

P.S. you can assume that I've taken differential equations and graduate-level courses in computer modeling and simulation, if that helps.

You can edit your comments instead of replying to yourself over and over.

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

#35

Post by niftich »

Retric wrote: post #23
Fiahil wrote: post #13

So, when should we start our preparation for the apocalypse? 2020? 2025?

Never. The issue with climate change is it's not going to harm wealthy people, so it's not a problem for them. In other words bad shit might happen to 75% of the worlds population, but so what. During the Irish potato famine, Ireland exported food. Think about that for a little bit. Throughout the entire period of the Famine, Ireland was exporting enormous quantities of food. Cormac O'Grada points out that, in Irelan…

Excellent point. It will affect different places differently, and those with means to work around it will suffer less than those without.

For example, Arctic shipping may become a year-round possibility, opening up the shortest routes between the east coast of Asia and either side of the northern Atlantic. Parts of Arctic countries may open up for intensive agriculture.

Meanwhile, the Maldives will be underwater, desertification will claim certain glasslands... this stuff is complex.

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

#37

Post by nxzero »

tim333 wrote: post #36

I wonder why it was at 400ppm 4m years ago. Presumably the Earth survived the last time.

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.

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

#38

Post by splawn »

Turing_Machine wrote: post #25
wolfram74 wrote: post #9

No no, that just won't do. Math and modeling doesn't allow us to draw conclusions about things we can't directly observe. Someone had to be there and directly count the co2 molecules with their own eyes or it doesn't count as evidence.

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.

Nice catch! It doesn't... the ice core measurements do show that it was waaay lower 800,000 yrs ago at 185ppm. To go beyond that they use other methods that are less accurate, but still good enough to at least get in the ballpark. Its admittedly a huge ballpark... 4M yrs is the conservative estimate while 25M yrs is the upper limit of what makes sense.

Here is my source: https://psmag.com/when-s-the-last-time-our-co2-levels-were-t...

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

#40

Post by chris_va »

tim333 wrote: post #32
danieltillett wrote: post #19

Earlier quoted context omitted.

Artificial trees are not considered geoengineering since they are just reversing the CO2 released. The really sad aspect is we are not putting in the R&D resources needed to develop them to the required scale. No matter what we do about preventing the release of more CO2, we need to deal with the CO2 that has already been released.

Regular trees work quite well and are cheaper. You just have to harvest them and not burn the wood, or turn it to biochar.

Actually burning the wood works just fine, provided you can sequester (see BECCS, along with recent developments in basalt based CCS).
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