Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Shazbot]

Neither plants nor humans grow their leaves and lungs equally. Just as an Olympic swimmer builds the lung capacity needed to perform in the low-oxygen environment of holding one's breath while performing strenuous exercise, so too does a plant's leaves adjust to their atmosphere. Stomata are the breathing apparatus for the inner leaf and open and close depending on water stress. However, the number of stomata per square inch of leaf is broadly controlled by how much gas exchange the leaf requires to operate. If you grow a plant in a high CO2 environment, photosynthesis is more efficient with more CO2 on hand for the C3/C4 cycles (think picking gold nuggets from thousands of worthless oxygen rocks on a conveyor belt). With less throughput required, less water is lost due to stomatas being fewer.

https://www.sciencedaily.com/releases/2011/03/110303111624.htm

Here they talk about how less water in the atmosphere because plants won't transpire it is a bad thing. I'm not sure. What I do know is that the climate has changed a hell of a lot, that three hundred million years ago a whole lot of trees turned into coal, and climate change may well be "fuck all in a big ship" that our grandchildren look back on like Malthusian population growth or Europe's 1500's firewood crisis. Thank God for coal or we'd all have frozen to death in barren, treeless hellscapes. I like that the most energy-producing regions of the country are tree-covered mountains full of ugly, black rocks. I met a guy who worked an 18-inch coal seam on his back for the better part of a mile, then I went hiking in the forest growing above it.

That which does not sort itself out, gets solved in some other way. C'mon nuclear power.

[Reelya]

That research however only looks at water transpiration per square-inch of the surface area of a leaf. Assuming this will mean less evaporation from plants also assumes that the amount of greenery is constant, but the CSIRO research I linked looking at actual plant growth shows that worldwide plant growth is up 17% but virtually no difference in the overall uptake of water. EDIT: Which makes sense: there's some plasticity in living things so that they adjust to the relative amounts of different nutrients. e.g. CO2 is increasing, but water and nitrogen are not, see the nitrogen-poor soybeans thing in PTTG's linked article. But if you have nitrogen-poor soybeans then the net effect of adding nitrogen to them will be greater. e.g. with the CO2 bottleneck removed, then other things become bottlenecks, but you might also gain more bang-for-your buck for adding them.

Also, with increased temperature you'd expect more evaporation of sea water, and i'm fairly confident that increased evaporation over 70% of the world's surface is going to be a bigger factor than whether individual plants are holding onto more water.

I'm therefore skeptical that we're going to get dry air purely on the basis that plants are more water-efficient.

[Starver]

Malthus is wrong for the same reason Judge Dredd* is wrong:

*and other 80s dystopias featuring crime, like for example Robocop

Yeah, well, Dredd would whup Robocop's ass. Unless Dredd just looks like Rocky, possibly.

(It's true, even if it's as irrelevant.)

[EnigmaticHat]

Robocop really likes standing there and letting people shoot him, so it comes down to whether Judge Dredd's ridiculously OP gun can beat Robocop's ridiculously OP armor.

In all seriousness tho, people from the 80s had this idea of a crime ridden dystopian future.  My point was that's the same basic statistical sin as the Victorians believing in an overpopulated future.  Or every cyberpunk story ever thinking that China/Japan will keep up their economic growth forever.  Japan being more of an old fashioned trope of course.  Can't look at the graph and assume it will keep going.

[Trekkin]

I don’t suppose we could get back on topic somehow?

Perhaps we can keep the high school botany lessons and related climatological bloviation contained in the crisis thread?

EDIT: forgot quote

[Reelya]

C'mon nuclear power.

Yeah, but no. Estimated cost-effective uranium deposits will last ~230 years. But that's the estimated size of both known and unknown deposits. Currently-provably-existing deposits are only 1/3rd of that total, and thus will last ~80 years at current rates. "Current rates" supply 11% of world electricity needs. If we boosted nuclear power by a factor of four, e.g. to supply just 44% of world needs, then known deposits will run out in 20 years, meaning that wouldn't give us enough time to discover the remaining deposits, nor to develop science to extra uranium from sources that are current uneconomical.

So sure, "future tech" nuclear is very promising. But if we build plants now or any time soon, we can only build them with current, proven technology, and those plants will suck down fresh uranium like there's literally no tomorrow, and very quickly exceed the rate at which we can find the stuff and pull it out of the ground. The economics of nuclear power based on uranium fission preclude it as being a major part of any anti-coal future.

[PTTG??]

Robocop really likes standing there and letting people shoot him, so it comes down to whether Judge Dredd's ridiculously OP gun can beat Robocop's ridiculously OP armor.

In all seriousness tho, people from the 80s had this idea of a crime ridden dystopian future.  My point was that's the same basic statistical sin as the Victorians believing in an overpopulated future.  Or every cyberpunk story ever thinking that China/Japan will keep up their economic growth forever.  Japan being more of an old fashioned trope of course.  Can't look at the graph and assume it will keep going.

And people from the '80s currently have this idea of a crime ridden dystopian present. Thanks to Fox, largely.

[Kagus]

C'mon nuclear power.

Yeah, but no.

Presumably you're including things like thorium in your blanket of uneconomical uranium sources, since their reactors need a bit of a redesign compared to uranium reactors, and good luck getting the necessary support for coming up with a new kind of functional nuclear reactor design when the current, highly refined and known designs already have the massive stigma that they do.

As far as chemistry is concerned, there are plenty of ways to induce fissile reactions in a cat. We just don't know all of them. That's kind of the fun part.


Also, when it comes to towering Dreddite megacities, I always just think of the Kowloon walled city, which presumably would have required a trained weapons team and "let God sort them out" sort of operating procedure in order to try and do some law enforcement inside there... if they'd ever really tried, that is.

Also, the Dredd vs. Death FPS was pretty great, even for just the first couple levels where you actually do much judging. Walking up to some poor fat lady with her little supportive belly wheel and putting her in the slammer for six months because of "obstruction"... Oof.

Also great fun just arresting innocent people:

"Get down on the ground, you're under arrest!"
"But I didn't do anything wrong!"
"Right, that's it, eight years in the big house for resisting arrest."

[Shazbot]

I also disagree about dry air due to plants becoming more water efficient. It seems like willfully ignoring how complex the systems really are.

In mining, the economical deposits get exhausted, the prices rise due to scarcity, and the uneconomical deposits become economical.

http://www.world-nuclear.org/information-library/nuclear-fuel-cycle/uranium-resources/supply-of-uranium.aspx

At $300/kg, seawater is economical.

From time to time concerns are raised that the known resources might be insufficient when judged as a multiple of present rate of use. But this is the Limits to Growth fallacy, a major intellectual blunder recycled from the 1970s, which takes no account of the very limited nature of the knowledge we have at any time of what is actually in the Earth's crust. Our knowledge of geology is such that we can be confident that identified resources of metal minerals are a small fraction of what is there. Factors affecting the supply of resources are discussed further and illustrated in the Appendix.

Then there's thorium or reprocessing "spent" fuel, and at sufficient prices all of that becomes economical.

[Reelya]

The problem with that logic, is that other energy sources also become more cost-effective vs uranium as the economically-viable deposits get depleted. Sure, ourrently non-viable deposits will be viable if the price of uranium rises, but in that scenario, electricity from uranium will also be more expensive so it has to compete with literally every other method of generating power. If uranium energy was a closed system with no external competition, that would be a better point.

Then there's thorium or reprocessing "spent" fuel, and at sufficient prices all of that becomes economical.

Yeah, "sufficient prices" e.g. "costs too much compared to non-nuclear", especially when other sources are likely to see continuous price drops over the next few decades.

[Karnewarrior]

[snip]
Actually, gonna move this to the happy-thread, since it's only vaguely on-topic here.

As far as Thorium goes, I think it looks very promising in the near future. Uranium, of course, is terrible for a number of reasons, and Thorium is AFAIK better in basically every way but ease of use, making it the coal of the nuclear family.

And our energy sources need only get us to the year we're finally able to put bigass solar panels up in space and beam it down to earth in super-tight laserbeams, or some equally sci-fi bit of imagery. Some of which are surprisingly close to being viable, if not in use.

[Dorsidwarf]

[snip]
Actually, gonna move this to the happy-thread, since it's only vaguely on-topic here.

As far as Thorium goes, I think it looks very promising in the near future. Uranium, of course, is terrible for a number of reasons, and Thorium is AFAIK better in basically every way but ease of use, making it the coal of the nuclear family.

And our energy sources need only get us to the year we're finally able to put bigass solar panels up in space and beam it down to earth in super-tight laserbeams, or some equally sci-fi bit of imagery. Some of which are surprisingly close to being viable, if not in use.

mmm, parboiled cities

[redwallzyl]

And our energy sources need only get us to the year we're finally able to put bigass solar panels up in space and beam it down to earth in super-tight laserbeams, or some equally sci-fi bit of imagery. Some of which are surprisingly close to being viable, if not in use.

Giant, Space, Lasers.

[Shazbot]

The problem with that logic, is that other energy sources also become more cost-effective vs uranium as the economically-viable deposits get depleted. Sure, ourrently non-viable deposits will be viable if the price of uranium rises, but in that scenario, electricity from uranium will also be more expensive so it has to compete with literally every other method of generating power. If uranium energy was a closed system with no external competition, that would be a better point.

Then there's thorium or reprocessing "spent" fuel, and at sufficient prices all of that becomes economical.

Yeah, "sufficient prices" e.g. "costs too much compared to non-nuclear", especially when other sources are likely to see continuous price drops over the next few decades.

I've always been one for "least expensive energy source". Nuclear power is at 2.10 cents per kilowatt. It can't be beat, at present, and is very competitive for new investment. But its a question for the investment bankers.

[MetalSlimeHunt]

Nobody is going to invest in nuclear and rightfully so. It takes decades (not hyperbole) to complete and ignite plants, this immediately makes it useless for the energy and climate crises as they will be decided in twenty years anyway. Further, the ROI is so long and so unlikely that you'd basically have to bribe the investors with their ROI upfront.