There is some good discussion here whether man-made CO2 as the cause of global warming or not.
I would lean towards real data derived from real physical experiments with real materials vs. defective synthetic climate models which have become so prevalent in academia.
I believe that the ice cores represent a reliable source of legitimate data about heating and cooling cycles and CO2 levels throughout history. The scientists involved appear to be competant and conservative as well.
Yes, there is a big difference between actual observations and readily-manipulated models. Please refer to the slide from journalist Peter D. Clack at the beginning of the article, "The Earth is Warming Because We are Exiting an Ice Age - Greenland ice core data from BC to present day reveals cyclic heating and cooling"
An important method for the study of long-term climate change involves isotope geochemistry. Oxygen is composed of 8 protons, and in its most common form with 8 neutrons, giving it an atomic weight of 16 (16O) -- this is know as a "light" oxygen. It is called "light" because a small fraction of oxygen atoms have 2 extra neutrons and a resulting atomic weight of 18 (18O), which is then known as "heavy" oxygen. 18O is a rare form and is found in only about 1 in 500 atoms of oxygen.
The ratio of these two oxygen isotopes has changed over the ages and these changes are a proxy to changing climate that have been used in both ice cores from glaciers and ice caps and cores of deep sea sediments. Many ice cores and sediment cores have been drilled in Greenland, Antarctica and around the world's oceans. These cores are actively studied for information on variations in Earth's climate.
Climate Temperature from Ice Cores
Figure 1. Light oxygen in water (H216O) evaporates more readily that water with heavy oxygen (H218O). Hence oceans will be relatively rich in 18O when glaciers grow and hold the precipitated 16O.
Ice in glaciers has less 18O than the seawater, but the proportion of heavy oxygen also changes with temperature. To understand why this might be so, we need to think about the process of glacier formation. The water-ice in glaciers originally came from the oceans as vapor, later falling as snow and becoming compacted in ice. When water evaporates, the heavy water (H218O) is left behind and the water vapor is enriched in light water (H216O). This is simply because it is harder for the heavier molecules to overcome the barriers to evaporation. Thus, glaciers are relatively enhanced in 16O, while the oceans are relatively enriched in 18O. This imbalance is more marked for colder climates than for warmer climates. In fact, it has been shown that a decrease of one part per million 18O in ice reflects a 1.5°C drop in air temperature at the time it originally evaporated from the oceans.
While there are complexities with the analysis, a simple measurement of the isotopic ratio of 18O in ice cores can be directly related to climate. Ice cores from Greenland or Antarctica are often layered, and the layers can be counted to determine age. The heavy oxygen ratio can then be used as a thermometer of ancient climates.....
Steffensen's views are misrepresented in your post
Like “rats inside the experiment,” Neils Bohr Institute glaciology professor Jorgen Peder Steffensen says of us humans when he considers the risks of a sudden reconfiguration of global circulation which could, among other things, cause long-term drying across America’s breadbasket states.
“That’s going to impact the entire world,” Steffensen cautions in recognizing that the 11,000 years of the interglacial period since the last ice age “has been unreasonably stable. And we don’t know why” or how long that stability may persist.
Steffensen, in exceptionally eloquent and straightforward language, acknowledges that models consistently point to a gradual global increase in temperatures as a result of the continue widespread combustion of fossil fuels and increased emissions of carbon dioxide. “But that’s assuming the climate plays nice,” he says.
“And we actually know from the ice cores that the climate does not play nice all the time.”
But he is concerned that human activities could be “tipping the climate into an intermediate period of climate changes….
Many unknowns remain, therefore there will be caveats, especially in terms of maintaining research funding. If one dares contradicting the current hysteria around "human caused global warming", one's career is over and may be smeared by the press and alienated by colleagues.
Nonetheless, I think it is difficult to decouple or extract all human activities from normal cyclical global warming and cooling. It could be a blip hidden in the noise of climate change, or part of the general trend.
Note the noise in the data showing climate change superimposed on the curve of ice age cycles. Climate change is normal in these 10,000 year cycles.
>The earth is 4.5 billion years old. Modern Man has been burning fossil fuels 200 years or so
>Where is heck is the climate data for the last 4.54299 billion years??
I am a retired industrial chemist, so I am always interested in both sides of the equation.
I would suggest that there are many gentlemen professors who built careers and depend the goldrush of research funding that supports the "CO2 causes global warming phenomenon".
Take a look at Charles' Law. Basically it says that CO2 solubility in water and in other material decreases with increasing temperature.
Take a look independently at the other planetary forces at play that are have orders of magnitude greater effect on earth temperatures. These include the sun and cloud reflection.
Charles's law, also known as the law of volumes, is an experimental gas law that describes how gases tend to expand when heated. The law states that when the pressure on a sample of a dry gas is held constant, the Kelvin temperature and the volume will be in direct proportion.
I think you are referencing Henry's Law, which is not applicable to CO2 in ocean water.
Henry's Law states that the amount of gas that dissolves in a liquid at a given temperature is directly proportional to the partial pressure of that gas above the liquid. This law is generally applicable to ideal gases and ideal solutions. However, the solubility of carbon dioxide (CO₂) in water often deviates from Henry's Law for several reasons:
Chemical Reactions: CO₂ does not simply dissolve in water; it reacts with water to form carbonic acid (H₂CO₃). This reaction alters the concentration of dissolved CO₂ and leads to a non-linear relationship between pressure and solubility.
Non-Ideal Behavior: At higher pressures, the behavior of CO₂ can become non-ideal due to interactions between CO₂ molecules and water molecules. This can lead to deviations from the predictions of Henry's Law.
Concentration Effects: As the concentration of dissolved CO₂ increases, the solution may become saturated, leading to a decrease in the solubility of additional CO₂. This saturation effect means that the relationship between pressure and solubility is not linear at higher concentrations.
Temperature Dependence: The solubility of CO₂ is also highly temperature-dependent. As temperature increases, the solubility of CO₂ generally decreases, which can complicate the application of Henry's Law.
In summary, while Henry's Law provides a useful approximation for the solubility of gases in liquids, the specific behavior of CO₂ in water due to its chemical reactivity, non-ideal interactions, and saturation effects can lead to significant deviations from the predictions of the law.
That why the pH level of the oceans is declining. The oceans are a CO2 sink even as ocean temperatures increase.
Hello Jack, you are correct. The carbon cycles and exchange with CO2 are non ideal and complex.
I maintain that the solubility of CO2 in the ocean increases with decreasing temperatures. This leads to further carbonate formation and precipitation. The gigatons of carbonates that precipitate further drives the quasi equilibrium and brings in more CO2.
The oceans are a CO2 sponge per the carbonate equilibrium. Plankton absorb CO2 on the gigatons scale.
The oceans which cover 75 percent of the planets surface, and vary in temperature so the exchange is in flux.
You are correct about clouds. Note that clouds are made of water, which is a greenhouse gas in itself. Clouds also reflect, this is called albedo. At anyone time clouds cover about 65 % of the planet. That is a profound effect.
Please note that I don't write with AI or use AI or the Internet in these discussions. It is by memory, so I might make errors.
Whatever the case, thank you for your insights and opinions. I am sure we could go back and forth quite a bit with this subject.
"Take a look independently at the other planetary forces at play that are have orders of magnitude greater effect on earth temperatures. These include the sun and cloud reflection."
Been there, done that.
What about natural forcings? Natural forcings would have us cooling.
When it comes to Earth’s climate, do clouds warm more than they cool, or is it the other way around? Well, that depends on where the clouds are in Earth’s atmosphere.
Clouds within a mile or so of Earth’s surface tend to cool more than they warm. These low, thicker clouds mostly reflect the Sun’s heat. This cools Earth’s surface.
Clouds high up in the atmosphere have the opposite effect: They tend to warm Earth more than they cool. High, thin clouds trap some of the Sun’s heat. This warms Earth’s surface.
Humans have adapted to far more extreme climate changes than what he is talking about. We are creatures of the African Savannah, but adapted to everything from deserts to temperate forests to the Arctic, we did that through technology and energy. At the same time it is more likely, much more likely, that increased CO2 within reasonable limits (which is what is happening) will be overall beneficial to both humans and Earth's biota as well.
The real risk is undertaking a $100T effort to replace fossil & nuclear energy with unproven or more accurately proven failed renewable energy scams which will destroy are ability to adapt to even current climate conditions, never mind future variations, whether natural or not. Add to that these variations in climate will seriously effect both wind & solar energy as the best locations will shift from present ones, rendering current wind & solar even less viable than it already is.
Add to those facts, we need a 5 fold increase in World primary energy supply to raise the standard of living of developing nations to that of modern Industrialized ones. The risks in failing to provide that energy, energy which is the critical resource for Climate Change Adaption, far, far outweigh the risks of potential climate anomalies. The worst anomaly by far would be a return to another glaciation cycle or even "little ice age" episode, hopefully the increased levels of CO2 will prevent those catastrophes from occurring.
So in conclusion, the real risk is not climate change, but our failure to develop a robust, economical and plentiful energy supply to sustain our civilization, and allow it to prosper. 90% of our focus should be on that, maybe 10% on mitigation. Even that 10% is unnecessary, since the only energy supply we can economically shift to is nuclear which by happy coincidence has the lowest emissions of any source of energy, by far.
Homo sapiens evolved and their food crops were domesticated in an atmosphere that never exceeded 300 ppm CO2. CO2 levels have not been this high in 14,000,000 years. The Earth has not been this warm in 100,000 years.
Funny how the same people pushing climate change alarmism also pushed everyone, including children, to wear masks which led them to breath air @ circa 1000ppm CO2, no problem there.
According to the Greenland Ice Cores there were 9 periods with temperatures higher than present in the past 10kyrs:
Humans evolved as hunter-gatherers, living in small groups of ~30 people, living largely on wild game w some roots, berries, fruits, for the past 300kyrs. Agriculture only 12kyrs.
Now humans live in huge cities, commonly alone, often in small apartments, eating processed foods, vaxxed to the max, living much longer now then for those 300kyrs. Those are vastly more significant changes than having CO2 levels of 400ppm and warmer average temperatures. And that's nothing compared to the changes our climate change fear porn overlords are demanding, i.e.: living in pods in giant apartment blocks in giant cities, socially disconnected, eating bugs for protein, restricted mobility, renting everything, no freedoms, monitored 24/7 with a social credit score = obey or don't eat.
I don't know of any science saying <600ppm is unhealthy for humans or other animals.
In any case they've had since 1990 Kyoto to institute their program, and it has been a dismal failure, resulting in not just increased emissions but an increasing rate of increase in emissions. The only success they had is in blockading nuclear power from completely replacing fossil electricity generation, which was the trend.
Until they unleash the nuclear juggernaut it is impossible to propose they really are being honest about their motives. Whatever they're up to, one thing is for sure, it ain't climate change mitigation.
Here is an example of failing to do your homework. You let your confirmation bias get in the way.
Steffensen affirms AGW
"But he is concerned that human activities could be “tipping the climate into an intermediate period of climate changes…. We can face a climate change that happens just as fast as the financial crisis,” Steffensen says. In that case, agricultural activity worldwide could be adversely affected … “the weather will change, and it will not change back” quickly.
“We don’t know where the threshold is,” Steffensen says of the ongoing human “experiment” with climate change. “But we are rats inside the experiment.”"
Sounds like more climate change Fear Porn, completely unjustified, even the IPCC doesn't believe that.
What is relevant is that fossil fuel demand is rapidly rising whereas supply isn't, we should be moving rapidly from an 85% fossil energy supply to an 85% nuclear energy supply, the only viable option. That is not happening and the people pushing climate change are the same bunch responsible for blockading nuclear energy. And that is a far, far more significant problem than climate change is. Indeed climate change problems are actually just one small subset of the nuclear blockade problem.
Davis, W. J. (2023). Mass extinctions and their relationship with atmospheric carbon dioxide concentration: Implications for Earth's future. Earth's Future, 11, e2022EF003336. https://doi.org/10.1029/2022EF003336
"The majority of extinction events occur in the CO2 concentration range of 700–1,100 ppmv."
Those extinction events had nothing to do with CO2 concentration. What is relevant is:
"People thrived during the previous 3 warm periods.
Minoan (1500 to 1200 BC)
Roman (250 BC to 450 AD)
Medieval (850-1250 AD)
Starvation & death was normal during the cold periods
Greek Dark Ages (1200 to 250 BC)
Dark Ages (450 to 850 AD)
Little Ice Age (1250 to 1850 AD)"
No reason to believe increased CO2 within the likely max of 600ppm (limited by economically viable fossil resource) will be anything but beneficial to humans and Earth's biota overall.
During the past glaciation cycle CO2 concentration dropped to the lowest level ever @ 180ppm. At 150ppm plants die. Shelled sea life is just too good at trapping carbon. Humans releasing a load of carbon during our fossil energy period has been a wonderful thing. Glaciation cycles are nasty, for all life, don't want any more of them.
Love this!
There is some good discussion here whether man-made CO2 as the cause of global warming or not.
I would lean towards real data derived from real physical experiments with real materials vs. defective synthetic climate models which have become so prevalent in academia.
I believe that the ice cores represent a reliable source of legitimate data about heating and cooling cycles and CO2 levels throughout history. The scientists involved appear to be competant and conservative as well.
Gene Nelson, Ph.D.
GreenNUKE
42m
Yes, there is a big difference between actual observations and readily-manipulated models. Please refer to the slide from journalist Peter D. Clack at the beginning of the article, "The Earth is Warming Because We are Exiting an Ice Age - Greenland ice core data from BC to present day reveals cyclic heating and cooling"
Tuco's Child Substack, April 25, 2025.
https://tucoschild.substack.com/p/the-earth-is-warming-because-we-are
Here's the introduction to an article about paleoclimate measurements....... A Brief Explanation of Oxygen Isotopes in Paleoclimate studies
Isotope Geochemistry
Source: http://www.globalchange.umich.edu/globalchange1/current/lectures/kling/paleoclimate/index.html
An important method for the study of long-term climate change involves isotope geochemistry. Oxygen is composed of 8 protons, and in its most common form with 8 neutrons, giving it an atomic weight of 16 (16O) -- this is know as a "light" oxygen. It is called "light" because a small fraction of oxygen atoms have 2 extra neutrons and a resulting atomic weight of 18 (18O), which is then known as "heavy" oxygen. 18O is a rare form and is found in only about 1 in 500 atoms of oxygen.
The ratio of these two oxygen isotopes has changed over the ages and these changes are a proxy to changing climate that have been used in both ice cores from glaciers and ice caps and cores of deep sea sediments. Many ice cores and sediment cores have been drilled in Greenland, Antarctica and around the world's oceans. These cores are actively studied for information on variations in Earth's climate.
Climate Temperature from Ice Cores
Figure 1. Light oxygen in water (H216O) evaporates more readily that water with heavy oxygen (H218O). Hence oceans will be relatively rich in 18O when glaciers grow and hold the precipitated 16O.
Ice in glaciers has less 18O than the seawater, but the proportion of heavy oxygen also changes with temperature. To understand why this might be so, we need to think about the process of glacier formation. The water-ice in glaciers originally came from the oceans as vapor, later falling as snow and becoming compacted in ice. When water evaporates, the heavy water (H218O) is left behind and the water vapor is enriched in light water (H216O). This is simply because it is harder for the heavier molecules to overcome the barriers to evaporation. Thus, glaciers are relatively enhanced in 16O, while the oceans are relatively enriched in 18O. This imbalance is more marked for colder climates than for warmer climates. In fact, it has been shown that a decrease of one part per million 18O in ice reflects a 1.5°C drop in air temperature at the time it originally evaporated from the oceans.
While there are complexities with the analysis, a simple measurement of the isotopic ratio of 18O in ice cores can be directly related to climate. Ice cores from Greenland or Antarctica are often layered, and the layers can be counted to determine age. The heavy oxygen ratio can then be used as a thermometer of ancient climates.....
Steffensen's views are misrepresented in your post
Like “rats inside the experiment,” Neils Bohr Institute glaciology professor Jorgen Peder Steffensen says of us humans when he considers the risks of a sudden reconfiguration of global circulation which could, among other things, cause long-term drying across America’s breadbasket states.
“That’s going to impact the entire world,” Steffensen cautions in recognizing that the 11,000 years of the interglacial period since the last ice age “has been unreasonably stable. And we don’t know why” or how long that stability may persist.
Steffensen, in exceptionally eloquent and straightforward language, acknowledges that models consistently point to a gradual global increase in temperatures as a result of the continue widespread combustion of fossil fuels and increased emissions of carbon dioxide. “But that’s assuming the climate plays nice,” he says.
“And we actually know from the ice cores that the climate does not play nice all the time.”
But he is concerned that human activities could be “tipping the climate into an intermediate period of climate changes….
https://yaleclimateconnections.org/2017/10/humans-experimenting-with-climates-playing-nice/
Thanks for your comment Jack.
Many unknowns remain, therefore there will be caveats, especially in terms of maintaining research funding. If one dares contradicting the current hysteria around "human caused global warming", one's career is over and may be smeared by the press and alienated by colleagues.
Nonetheless, I think it is difficult to decouple or extract all human activities from normal cyclical global warming and cooling. It could be a blip hidden in the noise of climate change, or part of the general trend.
Note the noise in the data showing climate change superimposed on the curve of ice age cycles. Climate change is normal in these 10,000 year cycles.
>The earth is 4.5 billion years old. Modern Man has been burning fossil fuels 200 years or so
>Where is heck is the climate data for the last 4.54299 billion years??
Richard Alley - 4.6 Billion Years of Earth’s Climate History: The Role of CO2
https://youtu.be/TNFsTLGUsGE?si=-5a2X2_WC9tiPM5m
Thank you Jack.
I am a retired industrial chemist, so I am always interested in both sides of the equation.
I would suggest that there are many gentlemen professors who built careers and depend the goldrush of research funding that supports the "CO2 causes global warming phenomenon".
Take a look at Charles' Law. Basically it says that CO2 solubility in water and in other material decreases with increasing temperature.
Take a look independently at the other planetary forces at play that are have orders of magnitude greater effect on earth temperatures. These include the sun and cloud reflection.
You may be surprised.
Thank you for stopping by.
TC
Charles's law, also known as the law of volumes, is an experimental gas law that describes how gases tend to expand when heated. The law states that when the pressure on a sample of a dry gas is held constant, the Kelvin temperature and the volume will be in direct proportion.
I think you are referencing Henry's Law, which is not applicable to CO2 in ocean water.
Henry's Law states that the amount of gas that dissolves in a liquid at a given temperature is directly proportional to the partial pressure of that gas above the liquid. This law is generally applicable to ideal gases and ideal solutions. However, the solubility of carbon dioxide (CO₂) in water often deviates from Henry's Law for several reasons:
Chemical Reactions: CO₂ does not simply dissolve in water; it reacts with water to form carbonic acid (H₂CO₃). This reaction alters the concentration of dissolved CO₂ and leads to a non-linear relationship between pressure and solubility.
Non-Ideal Behavior: At higher pressures, the behavior of CO₂ can become non-ideal due to interactions between CO₂ molecules and water molecules. This can lead to deviations from the predictions of Henry's Law.
Concentration Effects: As the concentration of dissolved CO₂ increases, the solution may become saturated, leading to a decrease in the solubility of additional CO₂. This saturation effect means that the relationship between pressure and solubility is not linear at higher concentrations.
Temperature Dependence: The solubility of CO₂ is also highly temperature-dependent. As temperature increases, the solubility of CO₂ generally decreases, which can complicate the application of Henry's Law.
In summary, while Henry's Law provides a useful approximation for the solubility of gases in liquids, the specific behavior of CO₂ in water due to its chemical reactivity, non-ideal interactions, and saturation effects can lead to significant deviations from the predictions of the law.
That why the pH level of the oceans is declining. The oceans are a CO2 sink even as ocean temperatures increase.
Lots of great information to consider, thank you.
Hello Jack, you are correct. The carbon cycles and exchange with CO2 are non ideal and complex.
I maintain that the solubility of CO2 in the ocean increases with decreasing temperatures. This leads to further carbonate formation and precipitation. The gigatons of carbonates that precipitate further drives the quasi equilibrium and brings in more CO2.
The oceans are a CO2 sponge per the carbonate equilibrium. Plankton absorb CO2 on the gigatons scale.
The oceans which cover 75 percent of the planets surface, and vary in temperature so the exchange is in flux.
You are correct about clouds. Note that clouds are made of water, which is a greenhouse gas in itself. Clouds also reflect, this is called albedo. At anyone time clouds cover about 65 % of the planet. That is a profound effect.
Please note that I don't write with AI or use AI or the Internet in these discussions. It is by memory, so I might make errors.
Whatever the case, thank you for your insights and opinions. I am sure we could go back and forth quite a bit with this subject.
Stay in touch,
TC
"I maintain that the solubility of CO2 in the ocean increases with decreasing temperatures." The oceans are warming and they are a CO2 sink.
"Take a look independently at the other planetary forces at play that are have orders of magnitude greater effect on earth temperatures. These include the sun and cloud reflection."
Been there, done that.
What about natural forcings? Natural forcings would have us cooling.
Milankovitch cycles.
https://climate.nasa.gov/ask-nasa-climate/2949/why-milankovitch-orbital-cycles-cant-explain-earths-current-warming/
Solar cycles
https://climate.nasa.gov/faq/14/is-the-sun-causing-global-warming/
Clouds
Clouds have been a warming and cooling effect.
When it comes to Earth’s climate, do clouds warm more than they cool, or is it the other way around? Well, that depends on where the clouds are in Earth’s atmosphere.
Clouds within a mile or so of Earth’s surface tend to cool more than they warm. These low, thicker clouds mostly reflect the Sun’s heat. This cools Earth’s surface.
Clouds high up in the atmosphere have the opposite effect: They tend to warm Earth more than they cool. High, thin clouds trap some of the Sun’s heat. This warms Earth’s surface.
Humans have adapted to far more extreme climate changes than what he is talking about. We are creatures of the African Savannah, but adapted to everything from deserts to temperate forests to the Arctic, we did that through technology and energy. At the same time it is more likely, much more likely, that increased CO2 within reasonable limits (which is what is happening) will be overall beneficial to both humans and Earth's biota as well.
The real risk is undertaking a $100T effort to replace fossil & nuclear energy with unproven or more accurately proven failed renewable energy scams which will destroy are ability to adapt to even current climate conditions, never mind future variations, whether natural or not. Add to that these variations in climate will seriously effect both wind & solar energy as the best locations will shift from present ones, rendering current wind & solar even less viable than it already is.
Add to those facts, we need a 5 fold increase in World primary energy supply to raise the standard of living of developing nations to that of modern Industrialized ones. The risks in failing to provide that energy, energy which is the critical resource for Climate Change Adaption, far, far outweigh the risks of potential climate anomalies. The worst anomaly by far would be a return to another glaciation cycle or even "little ice age" episode, hopefully the increased levels of CO2 will prevent those catastrophes from occurring.
So in conclusion, the real risk is not climate change, but our failure to develop a robust, economical and plentiful energy supply to sustain our civilization, and allow it to prosper. 90% of our focus should be on that, maybe 10% on mitigation. Even that 10% is unnecessary, since the only energy supply we can economically shift to is nuclear which by happy coincidence has the lowest emissions of any source of energy, by far.
Bravo, Smith FS !
Homo sapiens evolved and their food crops were domesticated in an atmosphere that never exceeded 300 ppm CO2. CO2 levels have not been this high in 14,000,000 years. The Earth has not been this warm in 100,000 years.
Funny how the same people pushing climate change alarmism also pushed everyone, including children, to wear masks which led them to breath air @ circa 1000ppm CO2, no problem there.
According to the Greenland Ice Cores there were 9 periods with temperatures higher than present in the past 10kyrs:
https://co2coalition.org/facts/temperatures-have-changed-for-800000-years-it-wasnt-us/
Humans evolved as hunter-gatherers, living in small groups of ~30 people, living largely on wild game w some roots, berries, fruits, for the past 300kyrs. Agriculture only 12kyrs.
Now humans live in huge cities, commonly alone, often in small apartments, eating processed foods, vaxxed to the max, living much longer now then for those 300kyrs. Those are vastly more significant changes than having CO2 levels of 400ppm and warmer average temperatures. And that's nothing compared to the changes our climate change fear porn overlords are demanding, i.e.: living in pods in giant apartment blocks in giant cities, socially disconnected, eating bugs for protein, restricted mobility, renting everything, no freedoms, monitored 24/7 with a social credit score = obey or don't eat.
I don't know of any science saying <600ppm is unhealthy for humans or other animals.
In any case they've had since 1990 Kyoto to institute their program, and it has been a dismal failure, resulting in not just increased emissions but an increasing rate of increase in emissions. The only success they had is in blockading nuclear power from completely replacing fossil electricity generation, which was the trend.
Until they unleash the nuclear juggernaut it is impossible to propose they really are being honest about their motives. Whatever they're up to, one thing is for sure, it ain't climate change mitigation.
Here is an example of failing to do your homework. You let your confirmation bias get in the way.
Steffensen affirms AGW
"But he is concerned that human activities could be “tipping the climate into an intermediate period of climate changes…. We can face a climate change that happens just as fast as the financial crisis,” Steffensen says. In that case, agricultural activity worldwide could be adversely affected … “the weather will change, and it will not change back” quickly.
“We don’t know where the threshold is,” Steffensen says of the ongoing human “experiment” with climate change. “But we are rats inside the experiment.”"
https://yaleclimateconnections.org/2017/10/humans-experimenting-with-climates-playing-nice/
Sounds like more climate change Fear Porn, completely unjustified, even the IPCC doesn't believe that.
What is relevant is that fossil fuel demand is rapidly rising whereas supply isn't, we should be moving rapidly from an 85% fossil energy supply to an 85% nuclear energy supply, the only viable option. That is not happening and the people pushing climate change are the same bunch responsible for blockading nuclear energy. And that is a far, far more significant problem than climate change is. Indeed climate change problems are actually just one small subset of the nuclear blockade problem.
Some science for you.
Davis, W. J. (2023). Mass extinctions and their relationship with atmospheric carbon dioxide concentration: Implications for Earth's future. Earth's Future, 11, e2022EF003336. https://doi.org/10.1029/2022EF003336
"The majority of extinction events occur in the CO2 concentration range of 700–1,100 ppmv."
We're halfway there.
Thank you for this reference.
There are thousands on both sides of the aisle.
Check out both sides and use your best judgement.
Regards,
TC
Been there done that . I affirm the scientific evidence.
Those extinction events had nothing to do with CO2 concentration. What is relevant is:
"People thrived during the previous 3 warm periods.
Minoan (1500 to 1200 BC)
Roman (250 BC to 450 AD)
Medieval (850-1250 AD)
Starvation & death was normal during the cold periods
Greek Dark Ages (1200 to 250 BC)
Dark Ages (450 to 850 AD)
Little Ice Age (1250 to 1850 AD)"
No reason to believe increased CO2 within the likely max of 600ppm (limited by economically viable fossil resource) will be anything but beneficial to humans and Earth's biota overall.
During the past glaciation cycle CO2 concentration dropped to the lowest level ever @ 180ppm. At 150ppm plants die. Shelled sea life is just too good at trapping carbon. Humans releasing a load of carbon during our fossil energy period has been a wonderful thing. Glaciation cycles are nasty, for all life, don't want any more of them.