Slashdot Mirror
Hoping That Sucking CO2 From the Air Will Fix the Climate? Good Luck (easac.eu)
From a study published on Thursday by scientists on the European Academies Science Advisory Council: Senior scientists from across Europe have evaluated the potential contribution of negative emission technologies (NETs) to allow humanity to meet the Paris Agreement's targets of avoiding dangerous climate change. They find that NETs have "limited realistic potential" to halt increases in the concentration of greenhouse gases in the atmosphere at the scale envisioned in the Intergovernmental Panel on Climate Change (IPCC) scenarios. This new report finds that none of the NETs has the potential to deliver carbon removals at the gigaton (Gt) scale and at the rate of deployment envisaged by the IPCC, including reforestation, afforestation, carbon-friendly agriculture, bioenergy with carbon capture and storage (BECCs), enhanced weathering, ocean fertilisation, or direct air capture and carbon storage (DACCs).
Use salt-waterable plants to turn the Sahara desert green and you'll reach gigaton absorption. For perspective, the Sahara is about the size of the United States.
...but humans are lazy. To which end, note the following:
I read somewhere recently, that - since the big campaigns for CO2 reduction started - humanity has increased CO2 output at an average rate of 1.6%. Before all this attention was focused on climate change, CO2 output was increased at an averate rate of... 1.6%. Even granting that reducing CO2 output is a good thing to do, it is quite apparent that we are not going to do so. None of the sequestration technologies make much sense, none of them (other than possibly reforestation) scale, and frankly some of them are hugely dangerous in their own right.
tl;dr: There's no point in fighting the inevitable. CO2 is going to continue to increase. Fortunately, this also means that there is no longer any reason to continue making exaggerated end-of-the world claims. The planet is warming, some anthropogenic, some natural. it will probably warm by a degree or even two in the next 80 years. Figure out what impact that's going to have, and deal with it.
Enjoy life! This is not a dress rehearsal.
I don't think the issue is removal, but sequestration. Eventually trees or other plants die and the carbon from the dead wood or plant matter must go somewhere. On a geologic time scale it becomes coal, oil, etc. but more immediately forest fires and the like will be returning a good chunk of it back to the atmosphere. Even if we could do something like ethanol in an efficient manner to where we could replace growing crops with drilling for oil, we're still just creating a carbon churn. The real task is finding something that's economically valuable to do with all of the carbon that's been pulled out of coal and oil deposits so that there's a real incentive for people to solve this problem. Telling them the world is going to end in 30, 100, 500 years unless we get our act together doesn't seem to work at all.
I think what we should be researching is how to fabricate carbon into building materials. We've already found that things like carbon fibers are incredibly useful in several domains, and carbon nanotubes have been shown to have orders of magnitude more tensile strength than other materials we're using now. Figuring out how to synthesize those things less expensively would provide economic incentive to capture carbon and a good long-term solution for sequestering it.
...by the Scientific calisthenics required derive a working AGW theory, that hasn't been show to be true by any empirical evidence.
The basic global circulation model incorporating the effect of anthropogenic carbon dioxide (what you call "AGW theory") has been around for fifty years now (the peer-reviewed publication was in two papers by Manabe and Wetherald, in 1967). That's long enough for the predictions to be compared with measurements.
Guess what? Over fifty years, the theory is pretty well matching measurements.
https://www.forbes.com/sites/startswithabang/2017/03/15/the-first-climate-model-turns-50-and-predicted-global-warming-almost-perfectly/
https://climategraphs.wordpress.com/2017/11/06/evaluating-the-prediction-of-manabe-and-wetherald-1967/
https://www.theguardian.com/environment/climate-consensus-97-per-cent/2014/mar/19/global-warming-accurate-prediction-1972
Anytime some authority insist that you give up freedom or money and the best they can do to justify it is to say, "It's complicated and you wouldn't understand, Trust Us", you know that something isn't right.
As it turns out, climate scientists have published extensive explanations of what they do, how they do it, how the models work, and all of the source code for their models. They don't say "trust us", they say "here's all the work we did, take a look at it."
As a starting point, look here: http://www.ipcc.ch/report/ar5/wg1 and then for the actual details, start reading some of the thousand references cited.
I'm pretty sure that blurb is not from the report. The conclusions of the report are
There's a lot of text around those bullets, but it doesn't read as doom and gloom to me.
From the introduction
Anyone who spends five minutes thinking about how carbon capture would work should understand that that's a pretty self evident statement.