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We Could Brighten Clouds to Cool the Earth

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Re: We Could Brighten Clouds to Cool the Earth

#121

Post by DennisP »

m0llusk wrote: post #95

This assumes that global warming is the problem, but arguably the most pressing aspect of carbon pollution is the acidification of the oceans which this plan would not address. It might make more sense to focus on capturing carbon pollution than to mitigate some of the side effects of rampant carbon pollution.

I think the most sensible use of SRM is to head off positive feedbacks. With increasing temperature, the planet starts emitting greenhouse gases on its own, from permafrost melt, forest fires, etc. We can see it in the geological record, where orbital variations cause a modest initial warming, then CO2 increases a lot and warms the planet several degrees more.

SRM could help prevent that by directly lowering temperature, which means less CO2 released and less ocean acidification. And it buys us time to decarbonize before things all fall apart.

Re: We Could Brighten Clouds to Cool the Earth

#122

Post by bobbytit »

willis936 wrote: post #81
bobbytit wrote: post #29

Earlier quoted context omitted.

Photosynthesis is limited by the availability of light, water, co2 and warmth.

This is like saying my computer's performance in a game is limited by CPU, GPU, and RAM while my CPU is maxed out 90% of the time.

Precisely. A plant is unable to perform to its full potential unless it is raised in an enclosed environment with supplemental CO2 at the ideal temperature and with adequate light and water. Plants outside never have enough carbon dioxide, though they often have more than they need of the other factors.

Re: We Could Brighten Clouds to Cool the Earth

#123

Post by blululu »

rob74 wrote: post #59
ericlavigne wrote: post #35

The most damaging hurricanes rely heavily on warm water over their last 2-3 days before landfall. Suppose we focused these bright cloud emitters on the water in front of a tropical storm, as a way to prevent it from strengthening into a hurricane? Imagine the city of Miami deciding that eliminating local hurricanes would benefit its local real estate market. They invest in a fleet of hurricane blockers to be deployed…

I think you're overestimating Miami's budget... sure, there are a lot of wealthy people living there, but that doesn't mean the city itself is that wealthy. BTW, if sea levels rise, property values in Miami are liable to go down the drain anyway, hurricanes or no hurricanes...

Probably not within the municipal budget of Miami, but Florida has a lot of clout in National Politics dues to the electoral college. Florida is the second largest net recipient of Federal tax dollars (after VA (proximity to DC)). If the cost of hurricane mitigation is less than the cost damages to coastal real estate in Florida then it would still be a good move on balance.

Re: We Could Brighten Clouds to Cool the Earth

#124

Post by SllX »

R0b0t1 wrote: post #107
spywaregorilla wrote: post #97

Earlier quoted context omitted.

I'm not sure I buy that, but sure, both are important problems. Question, what do we know about the ocean as a carbon sink? Is it's capture rate variable with anthing? Is it easier to capture carbon from the ocean than in the air? Could we try to increase the capture rate into the ocean and then extract rapidly from the same area?

It's "easier" to capture from water in chemical terms but harder to actually move the water. I think the economy of moving the weight of water makes this a nonstarter. Also yes, ocean acidification is likely to be the bigger immediate problem. People depend heavily on fish protein and other sealife. That plus poor farming yields will be bad.

Mechanical and electrical engineering aren’t going to do you enough good quickly enough.

But can you think of any forms of life on the bottom of the food chain that depend on carbon inputs as part of its own metabolic processes in order to reproduce itself? Because if you want a self-sustaining ocean-based carbon capture solution, that’s where I would look.

Re: We Could Brighten Clouds to Cool the Earth

#125

Post by sgc »

jean_tta wrote: post #99
tamaharbor wrote: post #83

Earlier quoted context omitted.

If sea levels rise there will be less available property which will ultimately cause property values to increase.

This assumes the demand for property stays the same. Is it likely, once it becomes obvious there's a chance your property will be destroyed by rising sea levels?

I used to think that obviously coastal real estate would plummet in value after a few high profile losses. After this pandemic I no longer think it will happen except very, very slowly. But the beaches will be gone for perhaps centuries, the sand will wash away / get covered in water. Sand does not form in a day. I have seen this in areas of Greece where there were earthquakes decades ago. Not even a hint of a beach remains.

Re: We Could Brighten Clouds to Cool the Earth

#126

Post by marcosdumay »

ncmncm wrote: post #27
TillE wrote: post #2

I think I'm a relative optimist about global warming because there are a number of possible climate engineering interventions which seem fairly cheap and could plausibly buy us another decade or so. I can imagine a future where perhaps India or China decides to act on their own to this effect, risks be damned.

All of the "climate engineering interventions" people keep trotting out that don't actually remove carbon from the air end up making things radically, disastrously worse. We know how to remove carbon from the atmosphere, in bulk, with super-plentiful olivine. Cutting off emissions and deploying olivine works. Almost anything else ends up doing no net good, at best, and funnels us deeper into the hole. Soluble iron co…

> those other manufactured gasses trap heat thousands or tens of thousands of times better than CO2 does, and are already a big part of the Problem.

If by big you mean 1/5 of the problem, ok. But that is really not big enough to remove the focus from the other 4/5 And the way those gases work on the long term, in that the amount of them on the atmosphere is proportional to the speed of emission, instead of total emissions makes any change of focus from CO2 actually harmful to solving the problem.

And by the way, half of the non-CO2 emissions are methane, that comes mostly from fossil fuels mining and handling, and 2/3 of the rest are nitrous oxides, that comes almost entirely from fossil fuel burning. So "big" is really, really pushing it.

A source:

https://www.epa.gov/ghgemissions/overview-greenhouse-gases

Re: We Could Brighten Clouds to Cool the Earth

#128

Post by marcosdumay »

willis936 wrote: post #81
bobbytit wrote: post #29

Earlier quoted context omitted.

Photosynthesis is limited by the availability of light, water, co2 and warmth.

This is like saying my computer's performance in a game is limited by CPU, GPU, and RAM while my CPU is maxed out 90% of the time.

If you go and reduce your RAM because the limit is elsewhere, you may find out that it quickly becomes the bottleneck.

Re: We Could Brighten Clouds to Cool the Earth

#129

Post by sleepydog »

SllX wrote: post #124
R0b0t1 wrote: post #107

Earlier quoted context omitted.

It's "easier" to capture from water in chemical terms but harder to actually move the water. I think the economy of moving the weight of water makes this a nonstarter. Also yes, ocean acidification is likely to be the bigger immediate problem. People depend heavily on fish protein and other sealife. That plus poor farming yields will be bad.

Mechanical and electrical engineering aren’t going to do you enough good quickly enough. But can you think of any forms of life on the bottom of the food chain that depend on carbon inputs as part of its own metabolic processes in order to reproduce itself? Because if you want a self-sustaining ocean-based carbon capture solution, that’s where I would look.

So like a smaller version of this? https://en.wikipedia.org/wiki/Azolla_event

e.g, instigate some large bloom of plant matter or algae, and engineer/find the right conditions for the matter to sink to the bottom of the ocean without decomposing.

Re: We Could Brighten Clouds to Cool the Earth

#130

Post by aeroman »

dhimes wrote: post #116
aeroman wrote: post #105

Earlier quoted context omitted.

It also turns out that SRM might not even be able to save us if things get really bad. The marine stratocumulus clouds they talk about depend on being able to cool to space (at the top). If you increase CO2 too much, this can no-longer happen, causing a collapse of the cloud system and a large decrease in planetary albedo (and hence warming) [0]. These SRM techniques are no silver bullet. However, as other have point…

SRM = Solar Radiation Management, in case anyone else was wondering.

Thanks! For some reason I thought it had already been mentioned
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