We cannot do much about heat from the core, but that's essentially steady state in the short term (50 year time scales) and declining in the long term (heading towards a cold rock).
We cannot do anything about the output of the sun, we can 'shade' ourselves by blowing bubbles in space or by (very very carefully) altering the atmosphere.
We can more directly alter our CO2 output and work on recovery from the atmosphere.
You are correct in that the earth core is really well insulated from the surface. So well that the light of the sun delivers an order of magnitude more energy per M2 to the Earth's surface.
That information also answers your question, our problem isn't with the amount heat we produce, it's with how much of that solar radiation we trap in our atmosphere due to the green house effect of CO2 and similar gases.
So yeah we introduce a little bit more heat by drawing from the Earth's core, but it's nothing compared to what trapping the sun's energy with CO2 is doing to the planet right now.
Conversely using that energy to remove CO2 from the atmosphere might even cool the planet, but that's a question for the next generation.
The only mechanism we would have for significantly increasing the cooling of the Earth's core would involve heading the atmosphere well past the habitable band.
Ultimately if heat isn't radiating from the atmosphere, it isn't leaving the planet.
I feel that the issue at the moment is the more heat is being trapped due to a CO2-rich atmosphere rather than producing excessive heat. After all, the energy we produce is probably miniscule compared to the amount of energy Earth receives from the sun.
Well, if the first assumption doesn’t hold, we’ll have to restrict our usage even more. Short of dimming the sun, I don’t see how you can keep “all this carbon in atmosphere” and still only get 2°C.
The Earth radiates an enormous amount of heat away into space(in fact the same amount that it receives from the sun), so all we really have to figure out (for a quick fix) is how to tip the balance negative enough to offset the additional warming from greenhouse gases.
Long term we need to stop the greenhouse effect, but things are getting dire way faster than even the most delusional optimist could forecast reversing emissions.
I agree with the analysis. The only thing I'd add (that they don't mention) is that the Earth's temperature will fluctuate wildly on it's own regardless of our CO2 output. We know this. The Earth dropped into an Ice Age and then got hot enough to thaw that ice age out all before we were even here. So the issue really has to do with finding ways to manipulate the Earth's temperature both ways, not just cool it down.
I recently thought... sure everyone says it's the CO², but then I saw articles that said, the CO² didn't change as much as they said it did. 4% of the atmosphere or so, because water takes it up and some kinds of stones do the same.
What if we generally just generate too much heat? And the heat gets trapped in the atmosphere? Every time someone uses energy, it generates heat. Everytime we make energy from hydrocarbon, we generate heat.
Would there be a way to let the heat go to space? Or if we want to preserve it on earth, a way to turn heat back into hydrocarbon?
My understanding is that it can't really affect it. To the extent we extract heat beyond what the greenhouse effect can warm the earth to, it will radiate out into space. The only real way to heat up the planet long-term is to prevent heat from radiating out by increasing greenhouse gasses.
But our planet (and with it, atmosphere) is hardly affected by humanity's activities adding heat directly. Instead it's GHGs that affect the inflow/outflow balance of heat from the sun.
The heat from gasoline you burn is quickly dissipated. But the CO2 produced has an effect for many decades to come.
Why would it cool in 12k years? We are loading the atmosphere with carbon sequestered over much longer periods. Some of which even happened in a phase of massive
imbalance in the evolutionary "war" between plants and plant consumers: trees had found a way to never rot (be consumed) which is rather tragic for incumbent biological systems but a crazy boost for carbon sequestering.
The problem is not that we produce heat, the problem is that we change the balance point between energy influx from the sun and energy emission to space. That changed balance point will remain changed much, much longer than 12k years. If we don't have a technological miracle, humans 12k in the future will live in tiny habitable zones near the poles.
Can you please give me some sort of published papers or something empirical to demonstrate that we have any control over this to a magnitude that matters?
As far as i’ve ever seen, we have no mechanism to cool the planet currently. Where does the idea that we have control come from? What’s the science?
First, there's about a 30-year lag between emissions and their full heating effect, much like it takes time for water to boil after you turn on the stove.
More importantly, if we go beyond about +2 degrees C, it's likely that positive feedbacks will take over and add several more degrees, with no more help from us. Feedbacks include ice cap melt (so less sunlight is reflected away), CO2 and methane emissions from melting permafrost, and forest fires brought on by drought.
We know this is likely, because you're right about those cycles. In geological history, there have been times when orbital variations caused a small initial heating, and shortly after we see a big rise in greenhouse gases and temperature.
That's why we're worried about fixing things really soon, before that kicks in.
(We are not currently in one of those natural warming cycles, btw.)
These are extremely slow processes that take centuries to stop. Ever seen large ocean going tankers making turns? They need to start making their turn 15 minutes ahead of time, and once they finally start turning, you can't easily stop them anymore. They respond very slowly.
Our climate is like that: it takes ages to respond. We've been building up excess CO2 in the atmoisphere for over a century now, and we're finally starting to notice the effects. Even if we were to completely stop producing CO2 now, there's still enough CO2 in the atmosphere to continue to increase heat absorption. Even if we could remove all excess CO2 from the atmosphere somehow (we can't), it would still take time for the excess heat to disappear. (The quickest way to lose the excess heat is if we could somehow block the sun, which we can't and would be harmful in a dozen other ways.)
The problem is that this concept is really hard for most people to wrap their heads around, so people tend to simplify it in ways that emphasize the urgency but exaggerate the timeline of the effect, or at least sound like they do, because that's how most people tend to interpret that urgency.
So no, the Earth is not going to end in 4 years, but it will be 4 more years of accumulated damage that will have repercussions for centuries.
We have millions of years of data. It's been 100,000 years since temps were this high, but millions of years since CO2 was this high. It's not safe to drastically alter the thermal properties of the atmosphere of the only planet we have to live on. Just common sense.
If the first assumption doesn't hold, restricting ourselves will not matter.
> Short of dimming the sun, I don’t see how you can keep “all this carbon in atmosphere” and still only get 2°C.
This one assumes the carbon is main or even major substance that keeps heat on
Earth. You do realize that we have much more water in the atmosphere, and
water keeps heat much better than carbon? It's not as simple as "more carbon,
higher temperatures".
>Even if we completely stop emitting CO2 right now (which we can't), there would still be too much CO2 in the atmosphere for some time, leading to further heating and longer melting
Do you have any data on this? If you look at how quickly things cool off at night, Earth's biosphere reaches steady-state thermal equilibrium over the course of a few days. Your claim is essentially that we've already set off an albedo forcing function that we can't stop, and which is also stronger than existing negative feedback loops. Seems unlikely to me.
So basically the balancing point at which CO2-based heating stops is bounded by this 155K number, which I’m assuming relates to something really hot and bad on the surface. This means that with just this model we will all die.
Can we not just seed clouds to reflect lots of energy back into space though? Maybe that is a stupid idea, but I could come up with 10 ideas like that and maybe someone could come up with an idea like that, but which actually works.
Heat doesn't "really" get trapped by greenhouse gases.
The earth is constantly heated by the sun's light (light hits the air, heats the air; it hits the ground, it heats the ground) and it's constantly radiating heat away (the ground emits infrared and cools down). The hotter something is, the faster it emits heat, so based on the amount of incoming heat, the irradiated body hits a temperature where income=outgoing. More greenhouse gases just change the radiation/heat profile of the planet so that the point where income=outgoing ends up at a higher temperature.
You could actively cool the planet in principle, of course; but to do anything noticeable, you'd have to operate on geographical scales. You'd probably be better off building towers to the edge of the atmosphere and putting infrared radiators like this on top of those; otherwise, the your best bet would be to replace a few million square kilometres of a hot region with black paint and make sure there are never any clouds overhead.
We cannot do much about heat from the core, but that's essentially steady state in the short term (50 year time scales) and declining in the long term (heading towards a cold rock).
We cannot do anything about the output of the sun, we can 'shade' ourselves by blowing bubbles in space or by (very very carefully) altering the atmosphere.
We can more directly alter our CO2 output and work on recovery from the atmosphere.
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