Could 'cocktail geoengineering' save the climate?

July 24, 2017, Carnegie Institution for Science
New research from an international team of atmospheric scientists investigates for the first time the possibility of using a "cocktail" of geoengineering tools to reduce changes in both temperature and precipitation caused by atmospheric greenhouse gases. Credit: Ken Caldeira. Earth image courtesy of NASA.

Geoengineering is a catch-all term that refers to various theoretical ideas for altering Earth's energy balance to combat climate change. New research from an international team of atmospheric scientists published by Geophysical Research Letters investigates for the first time the possibility of using a "cocktail" of geoengineering tools to reduce changes in both temperature and precipitation caused by atmospheric greenhouse gases.

Carbon dioxide emissions from the burning of coal, oil, and gas not only cause the Earth to get hotter, they also affect weather patterns around the world. Management approaches need to address both warming and changes in the amount of rainfall and other forms of precipitation.

So-called solar aims to cool the planet by deflecting some of the Sun's incoming rays. Ideas for accomplishing this include the dispersion of light-scattering particles in the upper atmosphere, which would mimic the cooling effect of major volcanic eruptions.

However, climate-modeling studies have shown that while this scattering of sunlight should reduce the warming caused by greenhouse gases in the atmosphere, it would tend to reduce rainfall and other types of precipitation less than would be optimal.

Another approach involves thinning of high , which are involved in regulating the amount of heat that escapes from the planet to outer space. This would also reduce warming, but would not correct the increase in precipitation caused by global warming.

One method reduces rain too much. Another method reduces rain too little.

This is where the theoretical cocktail shaker gets deployed.

The team—which includes Carnegie's Ken Caldeira, Long Cao and Lei Duan of Zhejiang University, and Govindasamy Bala of the Indian Institute of Science—used models to simulate what would happen if sunlight were scattered by particles at the same time as the cirrus clouds were thinned. They wanted to understand how effective this combined set of tools would be at reversing , both globally and regionally.

"As far as I know, this is the first study to try to model using two different geoengineering approaches simultaneously to try to improve the overall fit of the technology," Caldeira explained.

The good news is that their simulations showed that if both methods are deployed in concert, it would decrease to pre-industrial levels, as desired, and on a global level rainfall would also stay at pre-industrial levels. But the bad news is that while global average climate was largely restored, substantial differences remained locally, with some areas getting much wetter and other areas getting much drier.

"The same amount of rain fell around the globe in our models, but it fell in different places, which could create a big mismatch between what our economic infrastructure expects and what it will get," Caldeira added. "More complicated geoengineering solutions would likely do a bit better, but the best solution is simply to stop adding to the atmosphere."

Caldeira said that the international collaboration of scientists (including scientists from China and India) undertook this research as part of a broader effort aimed at understanding the effectiveness and unintended consequences of proposed strategies for reducing climate change and its impacts.

Explore further: Cutting carbon dioxide helps prevent drying

More information: Simultaneous stabilization of global temperature and precipitation through cocktail geoengineering, Geophysical Research Letters (2017). DOI: 10.1002/2017GL074281 , http://onlinelibrary.wiley.com/doi/10.1002/2017GL074281/full

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julianpenrod
1 / 5 (5) Jul 24, 2017
Among other things, the at least questionable technique of trying to solve effects of tampering with the planet by tampering with it more. Someone is wearing a wool coat on a hot day. Do they remove the coat? No, simply put some blocks of ice under their clothes. But the ice could melt. So put some absorbent paper layers around the ice. But the paper will become soggy, so put a battery power heating unit under the clothes to vaporize the moisture. But that will heat the person further.
In the end, it's chemtrails, not "fossil fuels" that are causing climate change. That can be handled by government simply stopping the project.
Osiris1
1 / 5 (1) Jul 24, 2017
Chapter two to your description, julian. The ice melts and the meltwater picks up electrolytes leaching out of paper. The resulting conductive liquid shorts out the battery and the heating unit and electrocutes the person. OOUCCCHHHHH.
Osiris1
1 / 5 (3) Jul 24, 2017
Those 'climatologists' should stick to their cocktails. Drunk, they are a lot less dangerous.
Whydening Gyre
5 / 5 (3) Jul 24, 2017
I think making the earths own carbon sinks more efficient might be a better approach...
classicplastic
5 / 5 (1) Jul 24, 2017
I think making the earths own carbon sinks more efficient might be a better approach...


The only practical solution is to recapture and sequester enough CO2 to get back to pre-industrial levels, or wherever they need to be. Here's the general approach: http://williamcal...mits.pdf

Now, isolate the forced up/downwelling action from the natural environment with giant floating lagoons (grown from seacrete), take out all the moving parts, add a "latency" period in the middle to convert at least some of the phytoplankton into gigatons of cheap food, fodder and biofuel, which pays for the construction costs, then scale it up to 26,000 square miles and you've got carbon capture and sequestration, fast, cheap, practical and profitable.

Instead of arguing "The sky is falling!/No, it isn't!" we'll all be chanting "Thank God for our carbon bank!"

Fabulously profitable technology patents, anyone?
Whydening Gyre
5 / 5 (1) Jul 24, 2017
...
Instead of arguing "The sky is falling!/No, it isn't!" we'll all be chanting "Thank God for our carbon bank!"

Fabulously profitable technology patents, anyone?

CP, see this article for an interesting idea....
https://phys.org/...ons.html
classicplastic
5 / 5 (2) Jul 24, 2017
CP, see this article for an interesting idea....
https://phys.org/...ons.html


Thanks! Carbon nanotube wool manufacture from atmospheric carbon seems like a promising, though minor, approach. There seems to be as much upside with CNT products as mostly-untapped algae. And, certainly there's enough raw material to go around.

Some downsides that I see to CNT as a practical carbon-lowering approach:

1. $660/ton to manufacture CNT wool is going to cost a LOT when you get to the multiple-gigaton scale that's needed for climate stabilization.

2. The CNT process is very complicated. I like simple water movement up, pause and then down, converting CO2 into food etc., i.e. Oceanic Permaculture, a lot better.

3. CNT uses "molten lithium carbonate." But, lithium is also used in power storage batteries and, even before Tesla, it's already running low. As well as no moving parts, the "Songaea" process uses no external inputs.
manfredparticleboard
5 / 5 (3) Jul 25, 2017
In the end, it's chemtrails, not "fossil fuels" that are causing climate change. That can be handled by government simply stopping the project.

Really? You were doing so well with your analogy, I was ready to give a 5/5. And then you mentioned chemtrails...and all was lost. Once again; show me a mass spec reading of this supposed "chem" in a supposed "trail" ...then we'll talk.

Otherwise it's just a bunch of morons looking at high atmosphere condensation from engines and going...' Hey, will yoo lookit them thar funny lookin streaks in th' aire!! Mus' be wun uv them thar seecrut pro jecks or sumsuch!!!'
Whydening Gyre
not rated yet Jul 25, 2017
CP, see this article for an interesting idea....
https://phys.org/...ons.html


Thanks! Carbon nanotube wool manufacture from atmospheric carbon seems like a promising, though minor, approach. There seems to be as much upside with CNT products as mostly-untapped algae. And, certainly there's enough raw material to go around.

Yeah, but...
Think about how much co2 is already IN the water.
Using (a lot of)that potentially increases the oceans ability to absorb more atmospheric co2.
That's my conjecture, anyway...
classicplastic
not rated yet Jul 25, 2017
Yeah, but...
Think about how much co2 is already IN the water.
Using (a lot of)that potentially increases the oceans ability to absorb more atmospheric co2.
That's my conjecture, anyway...


Well, yes and no...

There are two different forms of oceanic carbon to consider: Gaseous CO2 and Organic Carbon.

1. CO2 gas in the atmosphere. This is acidic and absorbed chemically directly into the water's surface, turning the surface layer acidic. By this route, the ocean waters are currently at about 1/3 of total CO2 absorption capacity. So, we have a long way to go before removing carbon increases the water's capacity to absorb more carbon.

However... We've already reached the point where ocean acidification is already screwing up the base of the food chain and, if pH isn't raised again, there's a serious risk of the near-total collapse of the ocean's ecosystem.

Continued....
classicplastic
not rated yet Jul 25, 2017
Continued...
The lower water pH seriously interferes with anything that builds a calcium carbonate shell, including all shellfish, coral and some algae. If they can't build shells, the organisms die. If you like clam chowder, enjoy it now because it may not be around for much longer. See http://news.natio...bon.html for more detailed info.

2. Organic Carbon in the form of carbon that has been absorbed from the water by phytoplankton during photosynthesis, releasing the two Oxygen molecules back into the water, then the air. Normally, this OC is kept locked into the food chain as it moves up the line to the apex eaters, although a lot of it is released by feces, and then all is released when the creature, or the last eater that ate it, dies, or poops.

When that happens, ideally the OC, whatever the form, sinks into the ocean depths and remains at least 1,000-2,000 years, if it doesn't turn back into oil.

Continued...
classicplastic
not rated yet Jul 25, 2017
Continued...

According to Dr. Calvin (and others), we're at only about 2% of the deep ocean's capacity to store Organic Carbon long term. If we can buy a millennium or two of time to get our carbon act together, we'll surely figure out something sustainable, if we're not already converting it into food etc. for the coming 11 billion humans before the end of the century. Already, the resource wars have started and 800 million go to be hungry every night, some of whom won't wake up. Your basic Malthusian solution.

But, we need to get the OC buried down deep for this to work and simple settling is the normal mechanism. However, there's a gauntlet that it needs to run before it gets there: Bacteria located between c. 100m and 300m levels that eat the vast majority of organic carbon and re-release the carbon molecules back into the water in gaseous form, where it adds back to acidification.

Continued...
classicplastic
not rated yet Jul 25, 2017
Continued...

The way past the bacterial gauntlet is through forced downwelling, which moves the OC down faster than the bacteria can eat it.

This makes a big difference: When the downwelling is natural, say through ocean currents, the sequestration rate of this carbon soup is 240x what it is with simple settling. Isolating the powered downflow to keep it from mixing with other water will boost the sequestration rate even further.

To sum up the Songaea process:

1. Mid-depth ocean nutrients are brought to the surface, where they

2. Feed phytoplankton that eat dissolved gaseous carbon from the water and convert it into stable-ish organic carbon in the form of micro-plants that can double in population every 24 hours. Even with haphazard Nature, this sequesters half of all anthropogenic carbon releases.

Continued...
classicplastic
not rated yet Jul 25, 2017
Continued...

At present, about 98% of the ocean's capacity to do this natural carbon capture and sequestration is untapped. In the process, and because the nutrient-local water from the mid-depths is more neutral, pH is raised, making it easier for shells to grow, and the oceanic food chain to not collapse.

3. Hold this "plankton farm" isolated at the surface long enough to feed farmed fish, shellfish etc. and/or harvest the plankton directly as a wide-ranging all-Green feedstock that will directly replace fossil fuels and terrestrial agricultural products. Plankton chowder, anyone?

4. After the surface water CO2 from the atmosphere has been converted into OC, either harvest it (plankton and/or that which eats is) directly for use or else pump it quickly down quickly into the depths. Feces are especially good for transporting carbon downward.
classicplastic
not rated yet Jul 25, 2017
Continued...

5. Now, scale this isolated process, with no moving parts, up to about 26,000 square miles, about the size of the Gulf of Mexico, scattered all over the planet and the Earth will be more or less carbon-sustainable. Plus, it will save the whales.

Again, this general concept is detailed by Dr. Calvin and can be found at http://williamcal...its.pdf.

I've been working on the practical, patentable, game-changing technology to implement this concept since 1985, so it's a case of parallel discovery. All props to Dr. Calvin.

Normally, this is so critical that the right thing to do is just release the tech suite of about a dozen patents into the Commons. However, it would likely get lost in all of the unworkable ideas and it won't turn into a free commercial enterprise profit opportunity, which will bring in gigabucks of investment capital (rather than taxes) and keep the government out of it, which will no doubt screw it up.
manfredparticleboard
5 / 5 (1) Jul 25, 2017
All that sounds great, but how do you intend on maintaining this mega aqua-ponics system as essentialy monoculture, without disease pressure? High nutrient levels and warm water equals toxic dinoflagellates in many parts of the world. Fish farms are notorious for being disease concentrators and the surrounding ecosystems often take extra pressure they can't sustain.

Diversity equals sustainability in most cases.
Whydening Gyre
not rated yet Jul 28, 2017
CP,
That was an excellent and well thought out dissertation, However, wouldn't a more direct route to co2 removal from the upper levels of the ocean (and subsequent de-acidification) be helpful? Not too mention all of the carbon nano tube material produced... (Space elevators, here we come...:-))

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