I’m late to this party; my apologies. The primary “take home” of this report is to have emissions drive the simulations. How is this going to work? Will they simply choose a matrix of emission scenarios (low, medium, high) and proceed. Will that produce any more realistic projections? In her recent book, Judith Curry argues that the IPCC has “characterized the climate change problem [to focus] on meeting emissions targets that are arguable unachievable in the near term.” She goes on to say “the slow incremental risks of warming have been mischaracterized as urgent, leading to rapid implementation of policies that are not only costly and suboptimal, but arguably reduce societal resilience to weather and climate variability, whatever their causes.”
Dr. Curry makes a valid point that future scenarios should consider. Further, Richard Tol has argued that the first rule of any climate policy should be to do no economic harm. This is in line with the Iron Law of Climate Change. So, my questions become these: has anyone determined how “fast” we can replace coal and gas? Is it realistic to establish a political goal of “net-zero” without first truly identifying the impacts to the economy of that goal? I don’t think anyone has done this. Wouldn’t it be prudent for at least one scenario that reflects what is realistically possible to achieve? It seems to me that any plausible scenario must recognize what is achievable in the near-term, both in terms of industrial capacity and societal needs.
Hindsight is always 20-20. Does anyone else wonder what the world would be today had we not allowed Three Mile Island (“history’s only major disaster with a toll of zero dead, zero injured, and zero diseased”) to thwart nuclear power in America? Since that accident, we’ve started up plants totaling 107 GW of coal capacity. Had that capacity been nuclear, would “climate change” still be an “existential threat?”
That would be an interesting model scenario: return to 1979 and model more nuclear into the capacity mix to determine what the concentrations would be today. Foolish, yes, but interesting.
I hope the light at the end of the AR7 tunnel that you see is not the unrushing freight train of vested interests. Grant funding, tenure, political power, clicks, business income, NGO donations and not least, fame & fortune require an apocalyptic narrative. I remain skeptical .
Question. How do you model technological change? Example: Direct air capture of CO2 is currently not technically feasible & totally uneconomic at the scale needed yet they presume it will be by 2050 (in the NetZero by 2050 "plan").
Check the physics of the basic assumption in all, that increased CO2 will increase IR absorption. This is factually false, as shown in NASA Technical Memorandum 103957. This shows total absorption in the 14-16micron range, which is the only effective area for CO2.
Also, there is no scientific paper written to prove that the assumption is true.
So here we go, making huge decisions on an unproven hypothesis!
RIP RCP8.5 (&SSP5-8.5 with it) is becoming "unlikely". (Like the sun coming up in the west is becoming "unlikely".).
"..climate advocates wedded to apocalyptic messaging are not going to like a return to plausibility and may resist appropriate high-end scenarios."
Fair and diplomatic way of putting it. We expect the RCP8.5 (SSP5-8.5) Zombie will be propped up like weekend at Bernie's for as long as possible by "those crazy kids". (But nobody wants a rotting corpse wearing sunglasses and a toupee around forever.....)
No, neither I nor my colleagues have ever been involved in IPCC or CMIP. That said, hard to read the workshop respire and not conclude that our work has been considered. Should the community be less insular? Yes.
Sadly (tragically?) I’m not sure the IPCC can undo the damage it has done to the credibility of the science popularizers, and therefore to most scientists who speak from well earned and honest authority.
This is hopeful that the IPCC will begin using rational scenarios, though I am skeptical that in the end the rational realists will prevail. From a geologist’s perspective, it seems rather than modeling emissions alone it would be useful to model natural climate forces as the basis of the models then overlaying emissions modeling over that. These are forces that have driven climate for literally eons so it always seemed to me that’s where everything should start.
It has also always been curious to me how heat from the earth resulting from tectonic forces are completely dismissed as a long and even short cycle climate driver. It is said there are not enough volcanoes to make a difference yet terrestrial volcanoes are not really where the majority of the heat comes from. It is in deep trenches within the 50,000 miles of the ring of fire. There are two sources of heat to warm the oceans, the sun above and earth’s heat from below. One is being completely ignored yet good evidence exists that El Niño is driven by deep ocean geothermal heating. Tectonic features on Antarctica’s western shelf creates significant heat flow, melting glaciers from below. The same in the North Atlantic. These geological events are cyclical as pressure is built and released but not enough research has been done to fully understand these events.
James E Kamis. Has spent years working on his theory of Plate Climatology. When I first came across his work it mirrored what I had been thinking for quite some time but never put into words. He has a new book “Climate Impacts on Climate” quite interesting read. Many of the ideas have merit but getting research money that could confirm or refute the theory is problematic in the current environment.
Thank you. Fascinating. As someone with a mathematical background but no formal education in the physical sciences be found college freshman chemistry, though self education and attendance at various “climate science” presentations, I have developed a keen awareness of the problems inherent in almost all of the models widely referenced , including the fact that the assumptions utilized involve variables that when tested have no predictive value. As someone who considers themselves for a layman, I am very surprised that I have never seen or heard any previous reference to the geological impact of the influence plate tectonics o climate, as well as the complete absence in lay climate literature to the obvious impact of the Ring of Fire on ocean temperatures . You have further confirmed my belief in how unfortunately false preconceptions regarding the widely promoted. supposedly “scientific” conclusions regarding climate change have led at best to costly but largely ineffective actions and at worst counterproductive “solutions”.
Understanding paleo climate is part of a necessary component of a successful geologists journey. I am a geologist, not work as one. Geology colors everything I do. The great thing about geology is that it may be the last of the generalized sciences. Geologists must have a working knowledge of Physics, chemistry, biology, math and statistics. Much of geology is hidden below our feet so we often forget that the earth is dynamic because the earth’s pace is very slow until it’s not. We only hear about the occasional volcano or just the big earthquakes so we think that’s all there is. Can’t have that much impact.
The earth is in motion. If but for life CO2 would still be 7000 to 9000 PPM as it was 650 million years ago. The fast carbon cycle or biological carbon cycle is what one typically learns in school. CO2 released by most organisms to be taken up by plants in photosynthesis, which store carbon in the soil and the oceans which then eventually recycles to the atmosphere as plant matter in soil decays etc. the really important carbon cycle is the long carbon cycle. It is controlled by life and plate tectonics. It is long, very long!
Coral began to be more widespread and diversified by the Ordovician 500 million years ago. As life figured out how to make hard shells as houses, CO2 began to fall as it was sucked out of the air by the oceans and was then sequestered by life and buried in sediments. Coral formation exploded in the Devonian 430 million years ago. More carbonate deposition in the Devonian than any other time in earth’s history. There were massive reefs throughout the world. CO2 levels fell throughout the Silurian and accelerated through the Devonian, then, as Coral formation reached its peak, it sapped nearly all of the CO2 from the atmosphere (150 PPM) and the oceans then photosynthesis stopped, killing nearly 98% of all life on earth. For more than 100 million years, the earth had CO2 levels at or below q150 to 400 ppm. The continents moved, slammed into each other, either subducted under each other and made volcanoes or undersea trenches spewing heated water into the ocean depths, or built mountains bigger than the Himalayas which eroded away. CO2 began to go back into the atmosphere and by the time of the Jurassic, life was thriving in a big way with CO2 back to 4000 PPM. Toward the end of the Jurassic corals once again took hold and began to once again sequester a lot of CO2. The same thing may have happened but by the end of the Cretaceous (the second most prolific carbonate deposition) CO2 had been pulled down to about 1200 to 2000 PPM then corals along with the dinosaurs and about 70% of life was taken out by a probable asteroid. That didn’t end the CO2 sequestration however because Grass and many other C3 type plants proliferated, capturing much of the rest of the carbon. We now find ourselves in the second major CO2 reduction in earth’s history and in the 5th major ice age flirting with the lower limit of CO2 to allow photosynthesis. As it happens only two ice ages have occurred in periods of low CO2 the other three were when CO2 was greater than 2500 PPM. The last ice age that occurred at a time of low CO2 lasted 50 million years. We are only about 3 million years into the current ice age. That story is why I am a CO2 restoration proponent. Life thrives at higher CO2 levels. I do not doubt we are warming the planet with the rate we are restoring CO2 to the atmosphere. Not necessarily a bad thing. Warm is good, cold is bad. There is a bigger risk in my estimation from CO2 levels that are too low than those that are too high. Without this rise in CO2 we would have to wait another 60 million years or so before the next super continent is formed and carbon is restored to normal earth levels.
Very informative piece. And good news. One question:
The relation in the graph between CO2 emissions and Global Mean Temperature Increase during this century looks fairly linear. But my layman's understanding is that it's logarithmic. Why the difference?
They can make it look linear by manipulating the units on the x & y axis. Over the Holocene (last 10,000 yrs) there is no consistent relationship between global temperature and CO2 concentration.
CO2 is a "greenhouse" gas, but there are numerous feedbacks so no simple linear relationship. If only! Lol
I am happy to discuss the focus of my post. If you'd like to start a more general discussion of climate science there are plenty of better venues for that, such as Judy Curry's blog.
Thanks for reading and to everyone for staying on topic!
I’m late to this party; my apologies. The primary “take home” of this report is to have emissions drive the simulations. How is this going to work? Will they simply choose a matrix of emission scenarios (low, medium, high) and proceed. Will that produce any more realistic projections? In her recent book, Judith Curry argues that the IPCC has “characterized the climate change problem [to focus] on meeting emissions targets that are arguable unachievable in the near term.” She goes on to say “the slow incremental risks of warming have been mischaracterized as urgent, leading to rapid implementation of policies that are not only costly and suboptimal, but arguably reduce societal resilience to weather and climate variability, whatever their causes.”
Dr. Curry makes a valid point that future scenarios should consider. Further, Richard Tol has argued that the first rule of any climate policy should be to do no economic harm. This is in line with the Iron Law of Climate Change. So, my questions become these: has anyone determined how “fast” we can replace coal and gas? Is it realistic to establish a political goal of “net-zero” without first truly identifying the impacts to the economy of that goal? I don’t think anyone has done this. Wouldn’t it be prudent for at least one scenario that reflects what is realistically possible to achieve? It seems to me that any plausible scenario must recognize what is achievable in the near-term, both in terms of industrial capacity and societal needs.
Hindsight is always 20-20. Does anyone else wonder what the world would be today had we not allowed Three Mile Island (“history’s only major disaster with a toll of zero dead, zero injured, and zero diseased”) to thwart nuclear power in America? Since that accident, we’ve started up plants totaling 107 GW of coal capacity. Had that capacity been nuclear, would “climate change” still be an “existential threat?”
That would be an interesting model scenario: return to 1979 and model more nuclear into the capacity mix to determine what the concentrations would be today. Foolish, yes, but interesting.
I have it on good authority (internet climate alarm trolls) that there is no issue in the science and that the models are tracking accurately.
Are you saying here that the IPCC itself is starting to finally admit that is not the case?
I’m shocked to be Frank. I thought averaging the output of dozens of models with widely disparate outcomes was how science is done.
Nice post.
I hope the light at the end of the AR7 tunnel that you see is not the unrushing freight train of vested interests. Grant funding, tenure, political power, clicks, business income, NGO donations and not least, fame & fortune require an apocalyptic narrative. I remain skeptical .
Question. How do you model technological change? Example: Direct air capture of CO2 is currently not technically feasible & totally uneconomic at the scale needed yet they presume it will be by 2050 (in the NetZero by 2050 "plan").
Check the physics of the basic assumption in all, that increased CO2 will increase IR absorption. This is factually false, as shown in NASA Technical Memorandum 103957. This shows total absorption in the 14-16micron range, which is the only effective area for CO2.
Also, there is no scientific paper written to prove that the assumption is true.
So here we go, making huge decisions on an unproven hypothesis!
And isn’t that part of the spectrum overlane and swamped by water vapor?
RIP RCP8.5 (&SSP5-8.5 with it) is becoming "unlikely". (Like the sun coming up in the west is becoming "unlikely".).
"..climate advocates wedded to apocalyptic messaging are not going to like a return to plausibility and may resist appropriate high-end scenarios."
Fair and diplomatic way of putting it. We expect the RCP8.5 (SSP5-8.5) Zombie will be propped up like weekend at Bernie's for as long as possible by "those crazy kids". (But nobody wants a rotting corpse wearing sunglasses and a toupee around forever.....)
Were you invited to participate in the workshop? Given your recent work in this area I would think it would be a no brainer.
Do "higher ups" get to provide political overlays?
Count me as hopeful but skeptical.
No, neither I nor my colleagues have ever been involved in IPCC or CMIP. That said, hard to read the workshop respire and not conclude that our work has been considered. Should the community be less insular? Yes.
Sadly (tragically?) I’m not sure the IPCC can undo the damage it has done to the credibility of the science popularizers, and therefore to most scientists who speak from well earned and honest authority.
This is hopeful that the IPCC will begin using rational scenarios, though I am skeptical that in the end the rational realists will prevail. From a geologist’s perspective, it seems rather than modeling emissions alone it would be useful to model natural climate forces as the basis of the models then overlaying emissions modeling over that. These are forces that have driven climate for literally eons so it always seemed to me that’s where everything should start.
It has also always been curious to me how heat from the earth resulting from tectonic forces are completely dismissed as a long and even short cycle climate driver. It is said there are not enough volcanoes to make a difference yet terrestrial volcanoes are not really where the majority of the heat comes from. It is in deep trenches within the 50,000 miles of the ring of fire. There are two sources of heat to warm the oceans, the sun above and earth’s heat from below. One is being completely ignored yet good evidence exists that El Niño is driven by deep ocean geothermal heating. Tectonic features on Antarctica’s western shelf creates significant heat flow, melting glaciers from below. The same in the North Atlantic. These geological events are cyclical as pressure is built and released but not enough research has been done to fully understand these events.
James E Kamis. Has spent years working on his theory of Plate Climatology. When I first came across his work it mirrored what I had been thinking for quite some time but never put into words. He has a new book “Climate Impacts on Climate” quite interesting read. Many of the ideas have merit but getting research money that could confirm or refute the theory is problematic in the current environment.
Thank you. Fascinating. As someone with a mathematical background but no formal education in the physical sciences be found college freshman chemistry, though self education and attendance at various “climate science” presentations, I have developed a keen awareness of the problems inherent in almost all of the models widely referenced , including the fact that the assumptions utilized involve variables that when tested have no predictive value. As someone who considers themselves for a layman, I am very surprised that I have never seen or heard any previous reference to the geological impact of the influence plate tectonics o climate, as well as the complete absence in lay climate literature to the obvious impact of the Ring of Fire on ocean temperatures . You have further confirmed my belief in how unfortunately false preconceptions regarding the widely promoted. supposedly “scientific” conclusions regarding climate change have led at best to costly but largely ineffective actions and at worst counterproductive “solutions”.
Understanding paleo climate is part of a necessary component of a successful geologists journey. I am a geologist, not work as one. Geology colors everything I do. The great thing about geology is that it may be the last of the generalized sciences. Geologists must have a working knowledge of Physics, chemistry, biology, math and statistics. Much of geology is hidden below our feet so we often forget that the earth is dynamic because the earth’s pace is very slow until it’s not. We only hear about the occasional volcano or just the big earthquakes so we think that’s all there is. Can’t have that much impact.
The earth is in motion. If but for life CO2 would still be 7000 to 9000 PPM as it was 650 million years ago. The fast carbon cycle or biological carbon cycle is what one typically learns in school. CO2 released by most organisms to be taken up by plants in photosynthesis, which store carbon in the soil and the oceans which then eventually recycles to the atmosphere as plant matter in soil decays etc. the really important carbon cycle is the long carbon cycle. It is controlled by life and plate tectonics. It is long, very long!
Coral began to be more widespread and diversified by the Ordovician 500 million years ago. As life figured out how to make hard shells as houses, CO2 began to fall as it was sucked out of the air by the oceans and was then sequestered by life and buried in sediments. Coral formation exploded in the Devonian 430 million years ago. More carbonate deposition in the Devonian than any other time in earth’s history. There were massive reefs throughout the world. CO2 levels fell throughout the Silurian and accelerated through the Devonian, then, as Coral formation reached its peak, it sapped nearly all of the CO2 from the atmosphere (150 PPM) and the oceans then photosynthesis stopped, killing nearly 98% of all life on earth. For more than 100 million years, the earth had CO2 levels at or below q150 to 400 ppm. The continents moved, slammed into each other, either subducted under each other and made volcanoes or undersea trenches spewing heated water into the ocean depths, or built mountains bigger than the Himalayas which eroded away. CO2 began to go back into the atmosphere and by the time of the Jurassic, life was thriving in a big way with CO2 back to 4000 PPM. Toward the end of the Jurassic corals once again took hold and began to once again sequester a lot of CO2. The same thing may have happened but by the end of the Cretaceous (the second most prolific carbonate deposition) CO2 had been pulled down to about 1200 to 2000 PPM then corals along with the dinosaurs and about 70% of life was taken out by a probable asteroid. That didn’t end the CO2 sequestration however because Grass and many other C3 type plants proliferated, capturing much of the rest of the carbon. We now find ourselves in the second major CO2 reduction in earth’s history and in the 5th major ice age flirting with the lower limit of CO2 to allow photosynthesis. As it happens only two ice ages have occurred in periods of low CO2 the other three were when CO2 was greater than 2500 PPM. The last ice age that occurred at a time of low CO2 lasted 50 million years. We are only about 3 million years into the current ice age. That story is why I am a CO2 restoration proponent. Life thrives at higher CO2 levels. I do not doubt we are warming the planet with the rate we are restoring CO2 to the atmosphere. Not necessarily a bad thing. Warm is good, cold is bad. There is a bigger risk in my estimation from CO2 levels that are too low than those that are too high. Without this rise in CO2 we would have to wait another 60 million years or so before the next super continent is formed and carbon is restored to normal earth levels.
Very informative piece. And good news. One question:
The relation in the graph between CO2 emissions and Global Mean Temperature Increase during this century looks fairly linear. But my layman's understanding is that it's logarithmic. Why the difference?
They can make it look linear by manipulating the units on the x & y axis. Over the Holocene (last 10,000 yrs) there is no consistent relationship between global temperature and CO2 concentration.
CO2 is a "greenhouse" gas, but there are numerous feedbacks so no simple linear relationship. If only! Lol
I remain skeptical that this will affect much of the hysteria…
This is fantastic news.
Restores a little bit of hope in the integrity of the scientific process, even close to decision-makers.
I am happy to discuss the focus of my post. If you'd like to start a more general discussion of climate science there are plenty of better venues for that, such as Judy Curry's blog.
Thanks for reading and to everyone for staying on topic!