Not having children because of climate change hysteria just means the Earth gets inherited by people less susceptible to such maladaptive mind viruses, i.e. it is self-defeating at the most fundamental level.
Furthermore, what makes this extra ironic is that it is actually quite likely that global warming will *increases* the world's carr…
Not having children because of climate change hysteria just means the Earth gets inherited by people less susceptible to such maladaptive mind viruses, i.e. it is self-defeating at the most fundamental level.
Furthermore, what makes this extra ironic is that it is actually quite likely that global warming will *increases* the world's carrying capacity, not diminish it. In paleoclimatology, times of dearth, desertification, civilizational collapse, etc. were accompanied by cold spells, which create droughts. Conversely, a warmer planet is a wetter planet and a more fertile one as well, thanks to a more intensive fertilization effect. The Sahara was an edenic garden populated by rhinos and elephants when the world was 1-2C warmer. The opening up of Canada and Siberia to intensive agriculture, as well as more surprising areas like African highlands, will overwhelmingly make up for any marginal losses elsewhere.
As Scott Alexander alludes here, the impact of sea level rise is massively overstated. I will also add one more thing that might be a surprise to some: Most of the world's big coastal cities are *sinking* at a much faster rate due to the weight of all their buildings than due to sea level rise. And besides, no, 1% of SF and 10% of Manhattan will not disappear even if sea levels rise by three meters. Reminder that a third of the Netherlands is below sea level, with the deepest point being around 6 meters. They accomplished most of this during the pre-industrial era. You really believe a modern civilization (let alone a futuristic one) will have *any* problems whatsoever protecting its largest concentrations of GDP from water?
In reality, we should not be "fighting" global warming, but happily going along with it and perhaps even accelerating it.
Some examples of this from "Deep Future" by Curt Stager (professional climatologist, i.e. not a kook):
"Much of lowland Tokyo sank 6 to 13 feet (2 to 4 m) during the last century as a result of groundwater extraction; subsidence rates near the harbor can exceed 4 inches (10 cm) per year. Similar processes drive the soft ground beneath Bangkok, Thailand, downward as fast as 4.5 inches (12 cm) per year; that’s over twice the speed of Hansen’s extreme inundation estimate and forty times the recent rate of sea-level rise. And every year China’s largest city, Shanghai, sinks a third of an inch (10 mm) deeper into the Yangtze Delta. During the last century it dropped nearly 9 feet (3 m) and suffered billions of dollars in structural and flood damage.
These examples help to show what the future advance of the sea will really be like in most cases; slow, unrelenting, costly, exasperating, but rarely deadly to humans. It won’t be a frothing shoreward rush of waves, but it will still be well worth slowing down as much as possible, as residents of Shanghai and the other already-sinking cities would surely agree."
Stretched out as it is over many centuries, I consider this to be close to a non-issue.
Some parts of the world are actually rising. Scandinavia for example, up to 0,8 cm per year in some places. Due to the hundreds of meters of ice that pressed down the land during the last glacial maximum, as late as 20.000 years ago.
I don't think it is mainly the effect of the weight of the buildings. Some of it is geological, New Orleans is below sea level, I believe, because draining it to reduce yellow fever resulted in compression of the soil. Also, the Army Corps of Engineers has devoted a great deal of effort to keeping the Mississippi from changing its mouth as the delta builds out, so it is now dumping the soil it carries over the edge of the continental shelf, not letting it wash back to balance subsidence from the weight of past deposition (my memory of my geologist wife's account, but she is traveling at the moment so I can't check details with her — we lived in New Orleans for a while).
I was irritated years ago at an alarmist publication with a cover picture of flooding in a coastal area of the south, with no explanation that subsidence there was about twice as large as sea level rise.
The running joke in here New Orleans involves the 50% leak rate for the Sewer and Water Board. Without those leaking pipes, subsidence would be worse. Joking aside though, along with the sinking and subsidence of NOLA and LA gulf coast, coastal erosion & the channelization of the Mississippi are big contributors.
> Not having children because of climate change hysteria just means the Earth gets inherited by people less susceptible to such maladaptive mind viruses, i.e. it is self-defeating at the most fundamental level.
Even if you're going to be mercenary about this, my guess is that these are people whose genes you generally want in the next generation.
> Furthermore, what makes this extra ironic is that it is actually quite likely that global warming will *increases* the world's carrying capacity, not diminish it. In paleoclimatology, times of dearth, desertification, civilizational collapse, etc. were accompanied by cold spells, which create droughts. Conversely, a warmer planet is a wetter planet and a more fertile one as well, thanks to a more intensive fertilization effect. The Sahara was an edenic garden populated by rhinos and elephants when the world was 1-2C warmer. The opening up of Canada and Siberia to intensive agriculture, as well as more surprising areas like African highlands, will overwhelmingly make up for any marginal losses elsewhere.
I think it's plausible that millions of people will die because some megacity in Africa can no longer get water effectively. In the abstract, the earth's carrying capacity could very well go up, but unless you want to transport the city of Lagos to Quebec (I don't know whether the logistical or political problems would be harder!) we can't actually make use of that increased capacity to prevent millions of people from dying.
They're higher IQ and probably more conscientious and trusting of authority than average, so yes, that's probably true. I didn't say this would necessarily be good for society.
Oceanic transport is really, really cheap. Lagos is a coastal megapolis, and the Chinese are helpfully crisscrossing Africa with railways and expanding ports. I'm highly skeptical about "millions of people" dying. When *did* millions of people die of climatic causes in Africa? One prominent example would be the Ethiopian famine of the 1980s. Which in turn was thought to have been caused by "global dimming" https://en.wikipedia.org/wiki/Global_dimming , i.e. a diminution of solar intensity and heating at the tropics, which reduced the strength of the monsoon that fed Ethiopians. Yet another demonstration of the pattern that it's generally cooling that kills, not warming.
I wandered into a lecture as an undergrad about "sustainable food supply" and was interested to discover that the biggest issue for many nations in getting food to their citizens is less in the production of enough food to feed everyone, and more in the political structures that prevent appropriate distribution of food that has already been produced. Indeed, even charities that try to give food to people often run into the problem of corrupt local government seizing food that would otherwise be sufficient to end a famine. Why keep people from starving when you can take the food, export it for cash, and keep the crisis going?
This actually works for more than just food. Iron supplementation can save lots of lives in Africa, yet getting those simple, cheap iron supplements to the people who need them is often frustrated by corrupt local government. This doesn't even run into refrigeration issues for things like vaccines. It's a cheap, plentiful solution that's widely available (and provided for free by charitable organizations), and yet hundreds of thousands still die of it.
At a slight tangent, people talk as if water shortage means people dying of thirst. When I calculated the figure for the U.S. quite a long time ago, per capita water consumption was about a thousand gallons a day. That isn't drinking water, it's agricultural and industrial uses. You made the point long ago on SSC that all urban water consumption in California was less than what went to grow alfalfa.
A few years ago I saw data showing that only about 10% of CA water usage was residential, and about half of that was landscaping. The exhortations to use less household water (take shorter showers, etc.) are usually ridiculous in light of the scale of agricultural and industrial waste.
The water economist David Zetland has for decades been promoting proper water pricing as the solution to the vast majority of water shortages. Most water systems are run by governments, which have an incentive to under-price water to all customers. How often are politicians re-elected on platforms based on, "I'll charge more for water!"? Because of the incentives facing governments, this obvious public choice problem exists around the world, resulting in under-priced water leading to over use and aquifer depletion.
Of course, many misguided advocates for the poor also advocate for low water prices, which often tend to benefit the wealthy rather than the poor,
"I conclude this section by reminding readers that low water prices, by encouraging use, often harm the poor who are least able to cope with the resulting scarcity and shortage. In New Delhi, for example, around 40 percent of water is lost to leaks and theft and revenue covers only 40 percent of costs.12 The resulting lack of funds to run or expand the system (and water to flow though it) means the poor are more likely to get their water from tankers than the rich who are connected to the semi-functional, cheaper network (Vinayak and Sewak, 2016). Fuente et al. (2016), likewise, describe show subsidies in Nairobi are more likely to go to the rich than the poor. "
Zetland's solution is basically to price water appropriately and then provide rebates to the poor.
For an overview of the global pathologies of water pricing and how water should be priced, see Zetland's "The Role of Prices in Managing Water Scarcity," from which the paragraph above was taken, see
Of course all of this is obvious to most economists, and yet mainstream debate on water, at least in mass media, seems oblivious to common sense economics on this issue (as on most issues). What percentage of media coverage of current or future water shortages even mentions pricing as a solution? I'd say well under 1%.
Yes, but I do think we also need water for irrigation if we are to not have water shortage causing crop failure. And besides, the US has already been irrigating unsustainably -- draining 10,000 year aquifers -- for over a century...
We need to irrigate in some places, but not everywhere. In California, agriculture produces <2% of the GDP, and employs a few % of the population. It could stop doing agriculture altogether, and import all its food from wetter places.
On the other hand, one effect of CO2 fertilization is to reduce water requirements for plants. They can get the carbon they need while passing less air through the leaves, thus lose less water.
A priori a factor of 2, right? You need half the air to get the same amount of CO2, so half the water otherwise lost gets lost. But I thought a major purpose of transpiration at least in taller plants was to provide the motive force to haul water up from the soil, since (contra elementary school science class) capillary action is wholly inadequate. So I can't really see a redwood needing significantly less water. But maybe for grasses and crops?
I don't have data, but C3 plants (all important crops except maize and sugarcane) increase yield by about 30% with a doubling of CO2. If we assume the amount of CO2 they need is proportional to yield, which seems a plausible guess, they should need 1.3/2 =.65 as much water.
ATMOSPHERIC CO2 concentration was 160 to 200 μmol mol−1 during the Last Glacial Maximum (LGM; about 18,000 years ago)1, rose to about 275 (μmol mol−1 10,000 years ago2,3, and has increased to about 350 μmol mol−1 since 1800 (ref. 4). Here we present data indicating that this increase in CO2 has enhanced biospheric carbon fixation and altered species abundances by increasing the water-use efficiency of biomass production of C3 plants, the bulk of the Earth's vegetation. We grew oats (Avena sativa), wild mustard (Brassica kaber) and wheat (Triticum aes-tivum cv. Seri M82 and Yaqui 54), all C3 annuals, and selected C4 grasses along daytime gradients of Glacial to present atmospheric CO2 concentrations in a 38-m-long chamber. We calculated parameters related to leaf photosynthesis and water-use efficiency from stable carbon isotope ratios (13C/12C) of whole leaves. Leaf water-use efficiency and above-ground biomass/plant of C3 species increased linearly and nearly proportionally with increasing CO2 concentrations. Direct effects of increasing CO2 on plants must be considered when modelling the global carbon cycle and effects of climate change on vegetation.
I want to push back on this framing of the movement of a megacity in Lagos to Quebec. I see this a lot in climate debates, and I don't think people who use it understand how much it biases the skeptics against their arguments. Because that's not how this kind of thing works in real life.
A megacity in Lagos doesn't run out of water overnight and have to suddenly move to Quebec. Experts project these things to happen over 1-2 centuries. In that time, many generations come and go. Nobody has to actually relocate their family to depopulate Lagos. The next generation can see 50% of the children relocate to other cities and establish themselves there. They'll still come back to visit, but there's just more opportunity elsewhere. A city that shrinks in population by 50% every 25 years will have <1% its original population 200 years later. And nobody had to approve a government mega-project to do it.
This is literally happening to dying towns in Pennsylvania and other parts of what used to be called "steel country" in the US. When steel went to Japan in the 1970's and 1980's lots of small towns that produced coal to feed the steel mills in Pittsburgh, Allentown, and the like no longer had jobs available for the next generation. People still live in many of those small towns, but the populations are getting older as many from the upcoming generation find opportunity elsewhere. I've seen this firsthand.
That's not to discount major shifts in global population. But if you want to support an argument like the Laotian megacity disastrophe, you have to do it based on threshold effects. Not based on slow-clock, gradual resource depletion.
I strongly disagree. The increased carrying capacity, and higher average global income (estimated by the IPCC to be between 500 and 600% higher than today by centuries end), and improved technology (transportation, desalination, market networks, etc) will make it easier to transport water to this mythical city. Modern people don’t move to water, they bring water to them wherever they go.
I think the likelihood of millions dying from thirst due to climate change is extremely remote. I would suggest that overreactions to climate change could disrupt societies and markets enough to kill millions, though.
My framing of the issue is that society is complex and fragile. Climate change is a negative externality or wake generated by economic growth. Billions of people are counting on that economic growth to improve the lives of themselves and their children. It is very desirable that we continue economic and technological advancement while also minimizing this and other negative externalities. However, in no case should we kill the goose laying the golden eggs. And it is possible to kill this goose by taking misguided actions to reduce CO2. Derailing the economic growth of Africa COULD kill millions.
This is like a longer version of 'The climate has always changed' argument for doing little to nothing about the broader negative impacts on the environment caused by rapid, unchecked industrialization.
It's been theorized that the beginning of intensive rice cultivation in East Asia pushed back the onset of the next Ice Age. If so, that worked out splendidly. Otherwise, we wouldn't be discussing this, but exchanging stories about the mythical Summertime over a campfire.
The climate "skeptics" are no less susceptible to "maladaptive mind viruses". Like for example the one that says climate change isn't a thing to be skeptical about, but a certain hoax.
If we're going to have maladaptive mind viruses, we can at least not have them be a monoculture.
Could you identify where I expressed climate skepticism? Let alone claimed it was a hoax?
I happen to have a blog post from 2009 debunking AGW myths. http://akarlin.com/2009/06/global-warming-denial-myths/ The reality of AGW was always obvious to me. Conversely, the stance that AGW's effects *have to be* predominantly negative *are* a religion, much like climate change denial come to think of it (people are incredibly hostile to the notion that AGW might be neutral or even good, as demonstrated even by the otherwise rationalist Scott in his response to me with the bizarre scenario of Lagos running out of water).
Happily I snapped out of that apocalypse cult several years ago. A non cherry-picked reading of the paleoclimate literature demonstrates that the effects will be mixed at worst, and on the very low probability this is wrong, geoengineering is trivially cheap relative to carbon taxes and other Green projects (which hit the poor hardest).
Not having children because of climate change hysteria just means the Earth gets inherited by people less susceptible to such maladaptive mind viruses, i.e. it is self-defeating at the most fundamental level.
Furthermore, what makes this extra ironic is that it is actually quite likely that global warming will *increases* the world's carrying capacity, not diminish it. In paleoclimatology, times of dearth, desertification, civilizational collapse, etc. were accompanied by cold spells, which create droughts. Conversely, a warmer planet is a wetter planet and a more fertile one as well, thanks to a more intensive fertilization effect. The Sahara was an edenic garden populated by rhinos and elephants when the world was 1-2C warmer. The opening up of Canada and Siberia to intensive agriculture, as well as more surprising areas like African highlands, will overwhelmingly make up for any marginal losses elsewhere.
As Scott Alexander alludes here, the impact of sea level rise is massively overstated. I will also add one more thing that might be a surprise to some: Most of the world's big coastal cities are *sinking* at a much faster rate due to the weight of all their buildings than due to sea level rise. And besides, no, 1% of SF and 10% of Manhattan will not disappear even if sea levels rise by three meters. Reminder that a third of the Netherlands is below sea level, with the deepest point being around 6 meters. They accomplished most of this during the pre-industrial era. You really believe a modern civilization (let alone a futuristic one) will have *any* problems whatsoever protecting its largest concentrations of GDP from water?
In reality, we should not be "fighting" global warming, but happily going along with it and perhaps even accelerating it.
Some examples of this from "Deep Future" by Curt Stager (professional climatologist, i.e. not a kook):
"Much of lowland Tokyo sank 6 to 13 feet (2 to 4 m) during the last century as a result of groundwater extraction; subsidence rates near the harbor can exceed 4 inches (10 cm) per year. Similar processes drive the soft ground beneath Bangkok, Thailand, downward as fast as 4.5 inches (12 cm) per year; that’s over twice the speed of Hansen’s extreme inundation estimate and forty times the recent rate of sea-level rise. And every year China’s largest city, Shanghai, sinks a third of an inch (10 mm) deeper into the Yangtze Delta. During the last century it dropped nearly 9 feet (3 m) and suffered billions of dollars in structural and flood damage.
These examples help to show what the future advance of the sea will really be like in most cases; slow, unrelenting, costly, exasperating, but rarely deadly to humans. It won’t be a frothing shoreward rush of waves, but it will still be well worth slowing down as much as possible, as residents of Shanghai and the other already-sinking cities would surely agree."
Stretched out as it is over many centuries, I consider this to be close to a non-issue.
Another big example is Jakarta, which is supposedly sinking at 10cm a year in some places due to groundwater extraction.
Some parts of the world are actually rising. Scandinavia for example, up to 0,8 cm per year in some places. Due to the hundreds of meters of ice that pressed down the land during the last glacial maximum, as late as 20.000 years ago.
I don't think it is mainly the effect of the weight of the buildings. Some of it is geological, New Orleans is below sea level, I believe, because draining it to reduce yellow fever resulted in compression of the soil. Also, the Army Corps of Engineers has devoted a great deal of effort to keeping the Mississippi from changing its mouth as the delta builds out, so it is now dumping the soil it carries over the edge of the continental shelf, not letting it wash back to balance subsidence from the weight of past deposition (my memory of my geologist wife's account, but she is traveling at the moment so I can't check details with her — we lived in New Orleans for a while).
I was irritated years ago at an alarmist publication with a cover picture of flooding in a coastal area of the south, with no explanation that subsidence there was about twice as large as sea level rise.
The running joke in here New Orleans involves the 50% leak rate for the Sewer and Water Board. Without those leaking pipes, subsidence would be worse. Joking aside though, along with the sinking and subsidence of NOLA and LA gulf coast, coastal erosion & the channelization of the Mississippi are big contributors.
In addition areas with heavy mining and water extraction drop as much as 20cm - 50cm each year (though rarely on edge of sea).
There are places in heavily mined places that have small rivers that need to be pumped up (sorry for YT link - https://www.youtube.com/watch?v=LseK5gp66u8 )
> Not having children because of climate change hysteria just means the Earth gets inherited by people less susceptible to such maladaptive mind viruses, i.e. it is self-defeating at the most fundamental level.
Even if you're going to be mercenary about this, my guess is that these are people whose genes you generally want in the next generation.
> Furthermore, what makes this extra ironic is that it is actually quite likely that global warming will *increases* the world's carrying capacity, not diminish it. In paleoclimatology, times of dearth, desertification, civilizational collapse, etc. were accompanied by cold spells, which create droughts. Conversely, a warmer planet is a wetter planet and a more fertile one as well, thanks to a more intensive fertilization effect. The Sahara was an edenic garden populated by rhinos and elephants when the world was 1-2C warmer. The opening up of Canada and Siberia to intensive agriculture, as well as more surprising areas like African highlands, will overwhelmingly make up for any marginal losses elsewhere.
I think it's plausible that millions of people will die because some megacity in Africa can no longer get water effectively. In the abstract, the earth's carrying capacity could very well go up, but unless you want to transport the city of Lagos to Quebec (I don't know whether the logistical or political problems would be harder!) we can't actually make use of that increased capacity to prevent millions of people from dying.
They're higher IQ and probably more conscientious and trusting of authority than average, so yes, that's probably true. I didn't say this would necessarily be good for society.
Oceanic transport is really, really cheap. Lagos is a coastal megapolis, and the Chinese are helpfully crisscrossing Africa with railways and expanding ports. I'm highly skeptical about "millions of people" dying. When *did* millions of people die of climatic causes in Africa? One prominent example would be the Ethiopian famine of the 1980s. Which in turn was thought to have been caused by "global dimming" https://en.wikipedia.org/wiki/Global_dimming , i.e. a diminution of solar intensity and heating at the tropics, which reduced the strength of the monsoon that fed Ethiopians. Yet another demonstration of the pattern that it's generally cooling that kills, not warming.
Right, the Ethiopian famine. Why didn't all those starving Ethiopians go to a country that had food?
I wandered into a lecture as an undergrad about "sustainable food supply" and was interested to discover that the biggest issue for many nations in getting food to their citizens is less in the production of enough food to feed everyone, and more in the political structures that prevent appropriate distribution of food that has already been produced. Indeed, even charities that try to give food to people often run into the problem of corrupt local government seizing food that would otherwise be sufficient to end a famine. Why keep people from starving when you can take the food, export it for cash, and keep the crisis going?
This actually works for more than just food. Iron supplementation can save lots of lives in Africa, yet getting those simple, cheap iron supplements to the people who need them is often frustrated by corrupt local government. This doesn't even run into refrigeration issues for things like vaccines. It's a cheap, plentiful solution that's widely available (and provided for free by charitable organizations), and yet hundreds of thousands still die of it.
I don't think we are getting a functional global government on the radar, absent shit getting *really* bad
At a slight tangent, people talk as if water shortage means people dying of thirst. When I calculated the figure for the U.S. quite a long time ago, per capita water consumption was about a thousand gallons a day. That isn't drinking water, it's agricultural and industrial uses. You made the point long ago on SSC that all urban water consumption in California was less than what went to grow alfalfa.
A few years ago I saw data showing that only about 10% of CA water usage was residential, and about half of that was landscaping. The exhortations to use less household water (take shorter showers, etc.) are usually ridiculous in light of the scale of agricultural and industrial waste.
The water economist David Zetland has for decades been promoting proper water pricing as the solution to the vast majority of water shortages. Most water systems are run by governments, which have an incentive to under-price water to all customers. How often are politicians re-elected on platforms based on, "I'll charge more for water!"? Because of the incentives facing governments, this obvious public choice problem exists around the world, resulting in under-priced water leading to over use and aquifer depletion.
Of course, many misguided advocates for the poor also advocate for low water prices, which often tend to benefit the wealthy rather than the poor,
"I conclude this section by reminding readers that low water prices, by encouraging use, often harm the poor who are least able to cope with the resulting scarcity and shortage. In New Delhi, for example, around 40 percent of water is lost to leaks and theft and revenue covers only 40 percent of costs.12 The resulting lack of funds to run or expand the system (and water to flow though it) means the poor are more likely to get their water from tankers than the rich who are connected to the semi-functional, cheaper network (Vinayak and Sewak, 2016). Fuente et al. (2016), likewise, describe show subsidies in Nairobi are more likely to go to the rich than the poor. "
Zetland's solution is basically to price water appropriately and then provide rebates to the poor.
For an overview of the global pathologies of water pricing and how water should be priced, see Zetland's "The Role of Prices in Managing Water Scarcity," from which the paragraph above was taken, see
https://www.researchgate.net/publication/347906672_The_role_of_prices_in_managing_water_scarcity
Of course all of this is obvious to most economists, and yet mainstream debate on water, at least in mass media, seems oblivious to common sense economics on this issue (as on most issues). What percentage of media coverage of current or future water shortages even mentions pricing as a solution? I'd say well under 1%.
Yes, but I do think we also need water for irrigation if we are to not have water shortage causing crop failure. And besides, the US has already been irrigating unsustainably -- draining 10,000 year aquifers -- for over a century...
https://www.economist.com/the-economist-explains/2021/08/16/why-pumping-groundwater-isnt-a-long-term-solution-to-drought
We need to irrigate in some places, but not everywhere. In California, agriculture produces <2% of the GDP, and employs a few % of the population. It could stop doing agriculture altogether, and import all its food from wetter places.
On the other hand, one effect of CO2 fertilization is to reduce water requirements for plants. They can get the carbon they need while passing less air through the leaves, thus lose less water.
How much less water per doubling of CO2 concentration are we talking? 0.1%? 1%? 10%? 50%?
A priori a factor of 2, right? You need half the air to get the same amount of CO2, so half the water otherwise lost gets lost. But I thought a major purpose of transpiration at least in taller plants was to provide the motive force to haul water up from the soil, since (contra elementary school science class) capillary action is wholly inadequate. So I can't really see a redwood needing significantly less water. But maybe for grasses and crops?
I don't have data, but C3 plants (all important crops except maize and sugarcane) increase yield by about 30% with a doubling of CO2. If we assume the amount of CO2 they need is proportional to yield, which seems a plausible guess, they should need 1.3/2 =.65 as much water.
Thank you. Here's an abstract saying for some C3 plants tested, they observed a linear response in water use efficiency:
https://www.nature.com/articles/361061a0
--
ATMOSPHERIC CO2 concentration was 160 to 200 μmol mol−1 during the Last Glacial Maximum (LGM; about 18,000 years ago)1, rose to about 275 (μmol mol−1 10,000 years ago2,3, and has increased to about 350 μmol mol−1 since 1800 (ref. 4). Here we present data indicating that this increase in CO2 has enhanced biospheric carbon fixation and altered species abundances by increasing the water-use efficiency of biomass production of C3 plants, the bulk of the Earth's vegetation. We grew oats (Avena sativa), wild mustard (Brassica kaber) and wheat (Triticum aes-tivum cv. Seri M82 and Yaqui 54), all C3 annuals, and selected C4 grasses along daytime gradients of Glacial to present atmospheric CO2 concentrations in a 38-m-long chamber. We calculated parameters related to leaf photosynthesis and water-use efficiency from stable carbon isotope ratios (13C/12C) of whole leaves. Leaf water-use efficiency and above-ground biomass/plant of C3 species increased linearly and nearly proportionally with increasing CO2 concentrations. Direct effects of increasing CO2 on plants must be considered when modelling the global carbon cycle and effects of climate change on vegetation.
--
I want to push back on this framing of the movement of a megacity in Lagos to Quebec. I see this a lot in climate debates, and I don't think people who use it understand how much it biases the skeptics against their arguments. Because that's not how this kind of thing works in real life.
A megacity in Lagos doesn't run out of water overnight and have to suddenly move to Quebec. Experts project these things to happen over 1-2 centuries. In that time, many generations come and go. Nobody has to actually relocate their family to depopulate Lagos. The next generation can see 50% of the children relocate to other cities and establish themselves there. They'll still come back to visit, but there's just more opportunity elsewhere. A city that shrinks in population by 50% every 25 years will have <1% its original population 200 years later. And nobody had to approve a government mega-project to do it.
This is literally happening to dying towns in Pennsylvania and other parts of what used to be called "steel country" in the US. When steel went to Japan in the 1970's and 1980's lots of small towns that produced coal to feed the steel mills in Pittsburgh, Allentown, and the like no longer had jobs available for the next generation. People still live in many of those small towns, but the populations are getting older as many from the upcoming generation find opportunity elsewhere. I've seen this firsthand.
That's not to discount major shifts in global population. But if you want to support an argument like the Laotian megacity disastrophe, you have to do it based on threshold effects. Not based on slow-clock, gradual resource depletion.
Scott,
I strongly disagree. The increased carrying capacity, and higher average global income (estimated by the IPCC to be between 500 and 600% higher than today by centuries end), and improved technology (transportation, desalination, market networks, etc) will make it easier to transport water to this mythical city. Modern people don’t move to water, they bring water to them wherever they go.
I think the likelihood of millions dying from thirst due to climate change is extremely remote. I would suggest that overreactions to climate change could disrupt societies and markets enough to kill millions, though.
My framing of the issue is that society is complex and fragile. Climate change is a negative externality or wake generated by economic growth. Billions of people are counting on that economic growth to improve the lives of themselves and their children. It is very desirable that we continue economic and technological advancement while also minimizing this and other negative externalities. However, in no case should we kill the goose laying the golden eggs. And it is possible to kill this goose by taking misguided actions to reduce CO2. Derailing the economic growth of Africa COULD kill millions.
Because relying on imported water has worked out so well in the past?
This is like a longer version of 'The climate has always changed' argument for doing little to nothing about the broader negative impacts on the environment caused by rapid, unchecked industrialization.
It's been theorized that the beginning of intensive rice cultivation in East Asia pushed back the onset of the next Ice Age. If so, that worked out splendidly. Otherwise, we wouldn't be discussing this, but exchanging stories about the mythical Summertime over a campfire.
The climate "skeptics" are no less susceptible to "maladaptive mind viruses". Like for example the one that says climate change isn't a thing to be skeptical about, but a certain hoax.
If we're going to have maladaptive mind viruses, we can at least not have them be a monoculture.
Could you identify where I expressed climate skepticism? Let alone claimed it was a hoax?
I happen to have a blog post from 2009 debunking AGW myths. http://akarlin.com/2009/06/global-warming-denial-myths/ The reality of AGW was always obvious to me. Conversely, the stance that AGW's effects *have to be* predominantly negative *are* a religion, much like climate change denial come to think of it (people are incredibly hostile to the notion that AGW might be neutral or even good, as demonstrated even by the otherwise rationalist Scott in his response to me with the bizarre scenario of Lagos running out of water).
Happily I snapped out of that apocalypse cult several years ago. A non cherry-picked reading of the paleoclimate literature demonstrates that the effects will be mixed at worst, and on the very low probability this is wrong, geoengineering is trivially cheap relative to carbon taxes and other Green projects (which hit the poor hardest).