![ChrisMartzWX's tweet photo. What is my stance on climate change?
Well, I'll lay it out for all of you newcomers. Grab some popcorn! 🍿
First, I do not deny the fact that the Earth has warmed up by ~1.2°C since 1850. However, nobody knows precisely how much because of data quality issues (e.g., uneven surface station distribution; fragmented records, especially outside of the United States; station siting changes; and urban heat island contamination) that have not been (and likely cannot be) removed from the record.
But, I have no doubt that the Earth is [slightly] warmer than it was 175 years ago or that 𝑠𝑜𝑚𝑒 of that warming might be due to carbon dioxide (CO₂) emissions.
Second, contrary to what the online army of alarmist foot soldiers have 𝑚𝑖𝑠𝑙𝑒𝑑 people to believe, there are not really any so-called “fingerprints” that distinguish human-caused global warming from warming caused by other forcings / variability.
Numerous scientific papers claim to have found such a “fingerprint,” but the only evidence that they have presented is that the anomaly of interest is 𝑐𝑜𝑛𝑠𝑖𝑠𝑡𝑒𝑛𝑡 𝑤𝑖𝑡ℎ anthropogenic warming. But these authors fail to mention that said anomaly would also be consistent with natural warming.
Case in point, a reduction in low- and mid-altitude stratiform cloud cover, for instance, would allow more sunlight into the climate system, which would warm the oceans. A warmer ocean—all else being equal—increases the rate of evaporation, which raises the vapor pressure (humidity) contributing to polar amplification and faster land warming than the ocean (e.g., Compo & Sardeshmukh, 2008).
🔗https://t.co/sQurHsN80P / open-access: https://t.co/WVKvLrSV7k
All warming, natural or man-made, results in:
1⃣ Higher latitudes warming faster than both the mid-latitudes and tropics.
2⃣ Land heating up faster than the oceans.
This is just basic physics; look up heat capacity.
Also, an increase in, say, solar forcing would have the same material effect, though we can admittedly likely rule that out as the cause of modern trends because sunspot activity has been declining in recent decades. But the sun does affect our climate in ways that have not really been thoroughly researched because little, if any funding, is ever allocated for such projects by the funding agencies such as the National Science Foundation (NSF).
In any case, the 𝒃𝒆𝒔𝒕 empirical evidence that I have seen to suggest that there is probably [at least some] anthropogenic “fingerprint” on recent temperature increases is stratospheric cooling.
First, you need to understand that in atmospheric physics, heat flux is measured as power—measured in Watts (that is, Joules per second)—standardized per square meter of surface area. This is written as W/m².
Next, the average radiation flux into the atmosphere is on the order of 239 ± 3.3 W/m² of absorbed solar radiation (ASR) averaged over a year (Stephens et al., 2012). This means that in order for the Earth's surface to maintain a constant temperature, the surface must emit 239.7 ± 3.3 W/m² back to outer space.
🔗https://t.co/5z5iMdazRB / open-access: https://t.co/51Ys5w8BWj
Global warming theory maintains the direct radiative forcing from doubling atmospheric CO₂ levels (often noted as RF 2×CO₂) is 3.7 ± 0.4 W/m² (e.g., IPCC TAR, 2007). That means that the net outgoing longwave radiation (OLR) to outer space is reduced by 3.7 W/m², which creates an Earth energy imbalance (EEI), which leads to a slight warming tendency in the troposphere (surface to ~13 km altitude).
🔗https://t.co/0JkXIQRGDH (p. 357)
In the stratosphere (~13-50 km altitude), this causes a cooling tendency because less infrared radiation (IR) flux is moving upward from below. These relationships were first demonstrated in Manabe & Strickler (1964).
🔗https://t.co/JNaXP7nUC9
NASA satellite measurements indicate that cooling in the stratosphere has been observed since the late 1970s, although there has been very little cooling over the last 25 years, all the while the troposphere has continued to warm.
🔗https://t.co/hT0Oxwm2Io
That means that most of the warming observed since 2000 is likely natural OR perhaps partly caused by a reduction in stratospheric sulfate aerosol concentrations, an artifact of particulate aerosol pollution regulations in recent years.
But, yes, I would agree with most scientists that the cooling observed in the stratosphere, at least that from the 1970s to 2000, is most likely a result of CO₂ forcing.
So what?
What happens down here in the lower atmosphere in response to CO₂ forcing is a lot more nuanced.
Why?
Because here in the troposphere, there are feedbacks (largely cloud-related) and precipitation processes that affect the atmospheric radiation budget far more than CO₂. And how exactly clouds respond to warming in the troposphere, if at all, is not very well understood, and by extension, not well-modeled.
What we do know, theoretically speaking, is that the direct warming effect of RF 2×CO₂ is actually very small. Specifically, it is on the order of ~1°C (e.g., Wijngaarden & Happer, 2020).
🔗https://t.co/y5szlGBmjd
However, amplifying (or dampening) feedbacks that kick in as a response to radiative forcing mean that the real-world value—that is, the equilibrium climate sensitivity (ECS)—will be higher (lower) than the ~1°C figure derived from radiative transfer calculations.
So, three critical pieces information are unknown:
1⃣ Exactly how much warming has been man-made (since, let's say, 1950). We still don't know the answer to this because the coefficients that are used to ascribe anthropogenic versus natural forcings are all estimated from computer modeling, not real physical in-situ measurements.
2⃣ The exact value of ECS.
3⃣ Even if global warming is entirely man-made, is it really a net drawback to civilization? Is it a crisis? Is it a problem in the slightest?
To break it down:
• If ECS is <3°C, the climate is insensitive to GHGs, and impacts are exaggerated.
• If ECS is ≥3°C, the climate is sensitive to GHGs, and warming could be a concern.
The IPCC’s “best estimate” of ECS is 3°C with a range of 2-5°C.
🔗https://t.co/8Ntgszr1dC (pp. 44-45)
In 1994, using NASA's real-world bulk atmospheric temperature data, one of my mentors, Dr. John Christy and his co-worker, Dr. Richard McNider from the University of Alabama in Huntsville (UAH), calculated climate sensitivity by removing the effects of El Niño / La Niña and volcanic stratospheric aerosol injection (e.g., El Chichón, 1982; Mt. Pinatubo, 1991).
Christy and McNider found that the human-induced warming rate is about 0.09°C / decade (lower than observations of actual temperature increase). This, by the way, came with the stipulation that unknown mechanisms of internal variability or external forcing are assumed to be zero. I attended a lecture where he talked about this paper in detail.
🔗https://t.co/S2GEmUftKo
They then validated their 1994 findings in McNider & Christy (2017). Specifically, they found a near-identical anthropogenic warming rate of only 0.096°C / decade and a transient climate response (TCR) of 1.10 ± 0.26°K.
🔗https://t.co/zueJLn8V8w / open-access: https://t.co/eLcqeizbRh
Many other recent studies (e.g., Lewis & Curry, 2018; Scafetta, 2021; Spencer & Christy, 2023; Lewis, 2025) have all estimated ECS to be far lower than the IPCC AR6's “best estimate.”
🔗https://t.co/8G0sF8gy2p
🔗https://t.co/5TgNX7c1JN
🔗https://t.co/BxyO1XIbNP
🔗https://t.co/YNQhNajrrO
The jury on ECS is still out. 🤷♂️
What's more, in order to reliably detect anthropogenic influence on the climate system, EEI must be known to the nearest 0.1 W/m² (Von Schuckmann et al., 2016; Gebbie, 2021).
🔗https://t.co/T7SKxidZ4N / open-access: https://t.co/GD45cbhxIT
🔗https://t.co/L6vZKVVpXg
However, the aforementioned Stephens et al. (2012) estimates the EEI to be 0.6 ± 0.4 W/m², which is eight times larger than the anthropogenic detection limits. And the natural top-of-atmosphere (TOA) flux has a 6.6 W/m² margin of error, which is 66 times larger than the detection limits. This range of uncertainty remains in newer estimates, such as Loeb et al. (2021), which estimates EEI to be 1.12 ± 0.48 W/m².
🔗https://t.co/ynRTFd3LWZ
This means that 𝑚𝑜𝑠𝑡 (but not all!) of the observed global warming since 1950 could be natural and scientists would never know for certain (nor would most be humble enough to admit it because the vast majority of academics have high egos). Alternatively, warming could be mostly man-made like alarmists claim, but, even if that is the case, I'll ask again. . .
SO WHAT?
That doesn't mean it is an existential crisis or urgent problem.
The big unknown are CLOUDS. ☁️
Why?
Because (a) cloud albedo has a far greater impact on the atmospheric radiation budget than does CO₂, and (b) how clouds change in response, if at all, to CO₂ is unknown. What's more, cloud cover can (and does) change naturally without mankind's assistance for any number of reasons (e.g., El Niño / La Niña activity; ocean circulation changes; cosmic ray flux; etc.). Even a small decrease in global cloud area fraction (CAF) can more than offset any temperature rise caused by CO₂. Song et al. (2016), for instance, found that,
🗨️ “[𝐴]𝑙𝑡ℎ𝑜𝑢𝑔ℎ 𝑡ℎ𝑒 𝑔𝑟𝑒𝑒𝑛ℎ𝑜𝑢𝑠𝑒 𝑒𝑓𝑓𝑒𝑐𝑡 𝑐𝑎𝑛 𝑏𝑒 𝑒𝑛ℎ𝑎𝑛𝑐𝑒𝑑 𝑏𝑦 𝑖𝑛𝑐𝑟𝑒𝑎𝑠𝑖𝑛𝑔 𝐺𝐻𝐺𝑠 𝑎𝑛𝑑 𝑤𝑎𝑡𝑒𝑟 𝑣𝑎𝑝𝑜𝑟 𝑖𝑛 𝑡ℎ𝑒 𝑎𝑡𝑚𝑜𝑠𝑝ℎ𝑒𝑟𝑒, 𝑖𝑡 𝑐𝑎𝑛 𝑏𝑒 𝑤𝑒𝑎𝑘𝑒𝑛𝑒𝑑 𝑏𝑦 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑖𝑛𝑔 𝑐𝑙𝑜𝑢𝑑𝑠. 𝐼𝑓 𝑡ℎ𝑒𝑠𝑒 𝑡𝑤𝑜 𝑎𝑐𝑡𝑖𝑜𝑛𝑠 𝑜𝑓𝑓𝑠𝑒𝑡 𝑒𝑎𝑐ℎ 𝑜𝑡ℎ𝑒𝑟, 𝑎 ℎ𝑖𝑎𝑡𝑢𝑠 𝑜𝑓 𝑡ℎ𝑒 𝑔𝑙𝑜𝑏𝑎𝑙 𝑔𝑟𝑒𝑒𝑛ℎ𝑜𝑢𝑠𝑒 𝑒𝑓𝑓𝑒𝑐𝑡 𝑤𝑖𝑙𝑙 𝑟𝑒𝑠𝑢𝑙𝑡.”
🔗https://t.co/NHkmfOc08y
I don't deny that global warming is occurring. I never have. I don't even deny an anthropogenic influence on it either. I never have. What I do reject, however, is unchecked alarmism and climate activism, particularly from fellow scientists.
Activism is not science and has no place in science. If you are an activist, you cannot call yourself a scientist because you are not dispassionate and objective. This goes for the vast majority of self-described “climate scientists” who actively use social media and are well-known in the debate. Two notable exceptions on the other side of the spectrum from me, in my opinion, are Drs. Robert Rohde and Paul Williams, both of whom I have always had pleasant interactions with.
I also reject the idea that every weather event needs to be blamed on climate change with a rushed, half-baked attribution study (namely the ones done by the clowns at World Weather Attribution that are often not scientifically rigorous, but get plenty of news media attention by the Associated Press, CNN, The New York Times, and The Washington Post). Attribution “science” is fraudulent anyway because one of the architects behind it admitted to Politico in 2021 that it was designed with the intention of using it in litigation against oil and gas companies.
🔗https://t.co/ETUBune0A8
Conflict of interest much?
It should also be abundantly clear that climate is just a statistical description of the mean and variability of the climate system, including long-term weather. So, a change in climate is just a change in statistics. That is an outcome, not a force or accelerant that causes an extreme weather event to occur.
For what it's worth, I used to be a climate alarmist well before I got my degree in meteorology.
Now that I know a great deal (but not everything and never will) about atmospheric science, my position has evolved to a cooler heads point of view. Perhaps it is not my judgement that's clouded, but rather that of the alarmist arm-wavers who have high trust in both academic institutions and their government officials who spoon-feed them pre-canned talking points on the daily.](https://pbs.twimg.com/media/HL809qjXUAAq_Fa.png)
![ChrisMartzWX's tweet photo. What is my stance on climate change?
Well, I'll lay it out for all of you newcomers. Grab some popcorn! 🍿
First, I do not deny the fact that the Earth has warmed up by ~1.2°C since 1850. However, nobody knows precisely how much because of data quality issues (e.g., uneven surface station distribution; fragmented records, especially outside of the United States; station siting changes; and urban heat island contamination) that have not been (and likely cannot be) removed from the record.
But, I have no doubt that the Earth is [slightly] warmer than it was 175 years ago or that 𝑠𝑜𝑚𝑒 of that warming might be due to carbon dioxide (CO₂) emissions.
Second, contrary to what the online army of alarmist foot soldiers have 𝑚𝑖𝑠𝑙𝑒𝑑 people to believe, there are not really any so-called “fingerprints” that distinguish human-caused global warming from warming caused by other forcings / variability.
Numerous scientific papers claim to have found such a “fingerprint,” but the only evidence that they have presented is that the anomaly of interest is 𝑐𝑜𝑛𝑠𝑖𝑠𝑡𝑒𝑛𝑡 𝑤𝑖𝑡ℎ anthropogenic warming. But these authors fail to mention that said anomaly would also be consistent with natural warming.
Case in point, a reduction in low- and mid-altitude stratiform cloud cover, for instance, would allow more sunlight into the climate system, which would warm the oceans. A warmer ocean—all else being equal—increases the rate of evaporation, which raises the vapor pressure (humidity) contributing to polar amplification and faster land warming than the ocean (e.g., Compo & Sardeshmukh, 2008).
🔗https://t.co/sQurHsN80P / open-access: https://t.co/WVKvLrSV7k
All warming, natural or man-made, results in:
1⃣ Higher latitudes warming faster than both the mid-latitudes and tropics.
2⃣ Land heating up faster than the oceans.
This is just basic physics; look up heat capacity.
Also, an increase in, say, solar forcing would have the same material effect, though we can admittedly likely rule that out as the cause of modern trends because sunspot activity has been declining in recent decades. But the sun does affect our climate in ways that have not really been thoroughly researched because little, if any funding, is ever allocated for such projects by the funding agencies such as the National Science Foundation (NSF).
In any case, the 𝒃𝒆𝒔𝒕 empirical evidence that I have seen to suggest that there is probably [at least some] anthropogenic “fingerprint” on recent temperature increases is stratospheric cooling.
First, you need to understand that in atmospheric physics, heat flux is measured as power—measured in Watts (that is, Joules per second)—standardized per square meter of surface area. This is written as W/m².
Next, the average radiation flux into the atmosphere is on the order of 239 ± 3.3 W/m² of absorbed solar radiation (ASR) averaged over a year (Stephens et al., 2012). This means that in order for the Earth's surface to maintain a constant temperature, the surface must emit 239.7 ± 3.3 W/m² back to outer space.
🔗https://t.co/5z5iMdazRB / open-access: https://t.co/51Ys5w8BWj
Global warming theory maintains the direct radiative forcing from doubling atmospheric CO₂ levels (often noted as RF 2×CO₂) is 3.7 ± 0.4 W/m² (e.g., IPCC TAR, 2007). That means that the net outgoing longwave radiation (OLR) to outer space is reduced by 3.7 W/m², which creates an Earth energy imbalance (EEI), which leads to a slight warming tendency in the troposphere (surface to ~13 km altitude).
🔗https://t.co/0JkXIQRGDH (p. 357)
In the stratosphere (~13-50 km altitude), this causes a cooling tendency because less infrared radiation (IR) flux is moving upward from below. These relationships were first demonstrated in Manabe & Strickler (1964).
🔗https://t.co/JNaXP7nUC9
NASA satellite measurements indicate that cooling in the stratosphere has been observed since the late 1970s, although there has been very little cooling over the last 25 years, all the while the troposphere has continued to warm.
🔗https://t.co/hT0Oxwm2Io
That means that most of the warming observed since 2000 is likely natural OR perhaps partly caused by a reduction in stratospheric sulfate aerosol concentrations, an artifact of particulate aerosol pollution regulations in recent years.
But, yes, I would agree with most scientists that the cooling observed in the stratosphere, at least that from the 1970s to 2000, is most likely a result of CO₂ forcing.
So what?
What happens down here in the lower atmosphere in response to CO₂ forcing is a lot more nuanced.
Why?
Because here in the troposphere, there are feedbacks (largely cloud-related) and precipitation processes that affect the atmospheric radiation budget far more than CO₂. And how exactly clouds respond to warming in the troposphere, if at all, is not very well understood, and by extension, not well-modeled.
What we do know, theoretically speaking, is that the direct warming effect of RF 2×CO₂ is actually very small. Specifically, it is on the order of ~1°C (e.g., Wijngaarden & Happer, 2020).
🔗https://t.co/y5szlGBmjd
However, amplifying (or dampening) feedbacks that kick in as a response to radiative forcing mean that the real-world value—that is, the equilibrium climate sensitivity (ECS)—will be higher (lower) than the ~1°C figure derived from radiative transfer calculations.
So, three critical pieces information are unknown:
1⃣ Exactly how much warming has been man-made (since, let's say, 1950). We still don't know the answer to this because the coefficients that are used to ascribe anthropogenic versus natural forcings are all estimated from computer modeling, not real physical in-situ measurements.
2⃣ The exact value of ECS.
3⃣ Even if global warming is entirely man-made, is it really a net drawback to civilization? Is it a crisis? Is it a problem in the slightest?
To break it down:
• If ECS is <3°C, the climate is insensitive to GHGs, and impacts are exaggerated.
• If ECS is ≥3°C, the climate is sensitive to GHGs, and warming could be a concern.
The IPCC’s “best estimate” of ECS is 3°C with a range of 2-5°C.
🔗https://t.co/8Ntgszr1dC (pp. 44-45)
In 1994, using NASA's real-world bulk atmospheric temperature data, one of my mentors, Dr. John Christy and his co-worker, Dr. Richard McNider from the University of Alabama in Huntsville (UAH), calculated climate sensitivity by removing the effects of El Niño / La Niña and volcanic stratospheric aerosol injection (e.g., El Chichón, 1982; Mt. Pinatubo, 1991).
Christy and McNider found that the human-induced warming rate is about 0.09°C / decade (lower than observations of actual temperature increase). This, by the way, came with the stipulation that unknown mechanisms of internal variability or external forcing are assumed to be zero. I attended a lecture where he talked about this paper in detail.
🔗https://t.co/S2GEmUftKo
They then validated their 1994 findings in McNider & Christy (2017). Specifically, they found a near-identical anthropogenic warming rate of only 0.096°C / decade and a transient climate response (TCR) of 1.10 ± 0.26°K.
🔗https://t.co/zueJLn8V8w / open-access: https://t.co/eLcqeizbRh
Many other recent studies (e.g., Lewis & Curry, 2018; Scafetta, 2021; Spencer & Christy, 2023; Lewis, 2025) have all estimated ECS to be far lower than the IPCC AR6's “best estimate.”
🔗https://t.co/8G0sF8gy2p
🔗https://t.co/5TgNX7c1JN
🔗https://t.co/BxyO1XIbNP
🔗https://t.co/YNQhNajrrO
The jury on ECS is still out. 🤷♂️
What's more, in order to reliably detect anthropogenic influence on the climate system, EEI must be known to the nearest 0.1 W/m² (Von Schuckmann et al., 2016; Gebbie, 2021).
🔗https://t.co/T7SKxidZ4N / open-access: https://t.co/GD45cbhxIT
🔗https://t.co/L6vZKVVpXg
However, the aforementioned Stephens et al. (2012) estimates the EEI to be 0.6 ± 0.4 W/m², which is eight times larger than the anthropogenic detection limits. And the natural top-of-atmosphere (TOA) flux has a 6.6 W/m² margin of error, which is 66 times larger than the detection limits. This range of uncertainty remains in newer estimates, such as Loeb et al. (2021), which estimates EEI to be 1.12 ± 0.48 W/m².
🔗https://t.co/ynRTFd3LWZ
This means that 𝑚𝑜𝑠𝑡 (but not all!) of the observed global warming since 1950 could be natural and scientists would never know for certain (nor would most be humble enough to admit it because the vast majority of academics have high egos). Alternatively, warming could be mostly man-made like alarmists claim, but, even if that is the case, I'll ask again. . .
SO WHAT?
That doesn't mean it is an existential crisis or urgent problem.
The big unknown are CLOUDS. ☁️
Why?
Because (a) cloud albedo has a far greater impact on the atmospheric radiation budget than does CO₂, and (b) how clouds change in response, if at all, to CO₂ is unknown. What's more, cloud cover can (and does) change naturally without mankind's assistance for any number of reasons (e.g., El Niño / La Niña activity; ocean circulation changes; cosmic ray flux; etc.). Even a small decrease in global cloud area fraction (CAF) can more than offset any temperature rise caused by CO₂. Song et al. (2016), for instance, found that,
🗨️ “[𝐴]𝑙𝑡ℎ𝑜𝑢𝑔ℎ 𝑡ℎ𝑒 𝑔𝑟𝑒𝑒𝑛ℎ𝑜𝑢𝑠𝑒 𝑒𝑓𝑓𝑒𝑐𝑡 𝑐𝑎𝑛 𝑏𝑒 𝑒𝑛ℎ𝑎𝑛𝑐𝑒𝑑 𝑏𝑦 𝑖𝑛𝑐𝑟𝑒𝑎𝑠𝑖𝑛𝑔 𝐺𝐻𝐺𝑠 𝑎𝑛𝑑 𝑤𝑎𝑡𝑒𝑟 𝑣𝑎𝑝𝑜𝑟 𝑖𝑛 𝑡ℎ𝑒 𝑎𝑡𝑚𝑜𝑠𝑝ℎ𝑒𝑟𝑒, 𝑖𝑡 𝑐𝑎𝑛 𝑏𝑒 𝑤𝑒𝑎𝑘𝑒𝑛𝑒𝑑 𝑏𝑦 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑖𝑛𝑔 𝑐𝑙𝑜𝑢𝑑𝑠. 𝐼𝑓 𝑡ℎ𝑒𝑠𝑒 𝑡𝑤𝑜 𝑎𝑐𝑡𝑖𝑜𝑛𝑠 𝑜𝑓𝑓𝑠𝑒𝑡 𝑒𝑎𝑐ℎ 𝑜𝑡ℎ𝑒𝑟, 𝑎 ℎ𝑖𝑎𝑡𝑢𝑠 𝑜𝑓 𝑡ℎ𝑒 𝑔𝑙𝑜𝑏𝑎𝑙 𝑔𝑟𝑒𝑒𝑛ℎ𝑜𝑢𝑠𝑒 𝑒𝑓𝑓𝑒𝑐𝑡 𝑤𝑖𝑙𝑙 𝑟𝑒𝑠𝑢𝑙𝑡.”
🔗https://t.co/NHkmfOc08y
I don't deny that global warming is occurring. I never have. I don't even deny an anthropogenic influence on it either. I never have. What I do reject, however, is unchecked alarmism and climate activism, particularly from fellow scientists.
Activism is not science and has no place in science. If you are an activist, you cannot call yourself a scientist because you are not dispassionate and objective. This goes for the vast majority of self-described “climate scientists” who actively use social media and are well-known in the debate. Two notable exceptions on the other side of the spectrum from me, in my opinion, are Drs. Robert Rohde and Paul Williams, both of whom I have always had pleasant interactions with.
I also reject the idea that every weather event needs to be blamed on climate change with a rushed, half-baked attribution study (namely the ones done by the clowns at World Weather Attribution that are often not scientifically rigorous, but get plenty of news media attention by the Associated Press, CNN, The New York Times, and The Washington Post). Attribution “science” is fraudulent anyway because one of the architects behind it admitted to Politico in 2021 that it was designed with the intention of using it in litigation against oil and gas companies.
🔗https://t.co/ETUBune0A8
Conflict of interest much?
It should also be abundantly clear that climate is just a statistical description of the mean and variability of the climate system, including long-term weather. So, a change in climate is just a change in statistics. That is an outcome, not a force or accelerant that causes an extreme weather event to occur.
For what it's worth, I used to be a climate alarmist well before I got my degree in meteorology.
Now that I know a great deal (but not everything and never will) about atmospheric science, my position has evolved to a cooler heads point of view. Perhaps it is not my judgement that's clouded, but rather that of the alarmist arm-wavers who have high trust in both academic institutions and their government officials who spoon-feed them pre-canned talking points on the daily.](https://pbs.twimg.com/media/HL806YHWwAA3d1U.jpg)
![ChrisMartzWX's tweet photo. What is my stance on climate change?
Well, I'll lay it out for all of you newcomers. Grab some popcorn! 🍿
First, I do not deny the fact that the Earth has warmed up by ~1.2°C since 1850. However, nobody knows precisely how much because of data quality issues (e.g., uneven surface station distribution; fragmented records, especially outside of the United States; station siting changes; and urban heat island contamination) that have not been (and likely cannot be) removed from the record.
But, I have no doubt that the Earth is [slightly] warmer than it was 175 years ago or that 𝑠𝑜𝑚𝑒 of that warming might be due to carbon dioxide (CO₂) emissions.
Second, contrary to what the online army of alarmist foot soldiers have 𝑚𝑖𝑠𝑙𝑒𝑑 people to believe, there are not really any so-called “fingerprints” that distinguish human-caused global warming from warming caused by other forcings / variability.
Numerous scientific papers claim to have found such a “fingerprint,” but the only evidence that they have presented is that the anomaly of interest is 𝑐𝑜𝑛𝑠𝑖𝑠𝑡𝑒𝑛𝑡 𝑤𝑖𝑡ℎ anthropogenic warming. But these authors fail to mention that said anomaly would also be consistent with natural warming.
Case in point, a reduction in low- and mid-altitude stratiform cloud cover, for instance, would allow more sunlight into the climate system, which would warm the oceans. A warmer ocean—all else being equal—increases the rate of evaporation, which raises the vapor pressure (humidity) contributing to polar amplification and faster land warming than the ocean (e.g., Compo & Sardeshmukh, 2008).
🔗https://t.co/sQurHsN80P / open-access: https://t.co/WVKvLrSV7k
All warming, natural or man-made, results in:
1⃣ Higher latitudes warming faster than both the mid-latitudes and tropics.
2⃣ Land heating up faster than the oceans.
This is just basic physics; look up heat capacity.
Also, an increase in, say, solar forcing would have the same material effect, though we can admittedly likely rule that out as the cause of modern trends because sunspot activity has been declining in recent decades. But the sun does affect our climate in ways that have not really been thoroughly researched because little, if any funding, is ever allocated for such projects by the funding agencies such as the National Science Foundation (NSF).
In any case, the 𝒃𝒆𝒔𝒕 empirical evidence that I have seen to suggest that there is probably [at least some] anthropogenic “fingerprint” on recent temperature increases is stratospheric cooling.
First, you need to understand that in atmospheric physics, heat flux is measured as power—measured in Watts (that is, Joules per second)—standardized per square meter of surface area. This is written as W/m².
Next, the average radiation flux into the atmosphere is on the order of 239 ± 3.3 W/m² of absorbed solar radiation (ASR) averaged over a year (Stephens et al., 2012). This means that in order for the Earth's surface to maintain a constant temperature, the surface must emit 239.7 ± 3.3 W/m² back to outer space.
🔗https://t.co/5z5iMdazRB / open-access: https://t.co/51Ys5w8BWj
Global warming theory maintains the direct radiative forcing from doubling atmospheric CO₂ levels (often noted as RF 2×CO₂) is 3.7 ± 0.4 W/m² (e.g., IPCC TAR, 2007). That means that the net outgoing longwave radiation (OLR) to outer space is reduced by 3.7 W/m², which creates an Earth energy imbalance (EEI), which leads to a slight warming tendency in the troposphere (surface to ~13 km altitude).
🔗https://t.co/0JkXIQRGDH (p. 357)
In the stratosphere (~13-50 km altitude), this causes a cooling tendency because less infrared radiation (IR) flux is moving upward from below. These relationships were first demonstrated in Manabe & Strickler (1964).
🔗https://t.co/JNaXP7nUC9
NASA satellite measurements indicate that cooling in the stratosphere has been observed since the late 1970s, although there has been very little cooling over the last 25 years, all the while the troposphere has continued to warm.
🔗https://t.co/hT0Oxwm2Io
That means that most of the warming observed since 2000 is likely natural OR perhaps partly caused by a reduction in stratospheric sulfate aerosol concentrations, an artifact of particulate aerosol pollution regulations in recent years.
But, yes, I would agree with most scientists that the cooling observed in the stratosphere, at least that from the 1970s to 2000, is most likely a result of CO₂ forcing.
So what?
What happens down here in the lower atmosphere in response to CO₂ forcing is a lot more nuanced.
Why?
Because here in the troposphere, there are feedbacks (largely cloud-related) and precipitation processes that affect the atmospheric radiation budget far more than CO₂. And how exactly clouds respond to warming in the troposphere, if at all, is not very well understood, and by extension, not well-modeled.
What we do know, theoretically speaking, is that the direct warming effect of RF 2×CO₂ is actually very small. Specifically, it is on the order of ~1°C (e.g., Wijngaarden & Happer, 2020).
🔗https://t.co/y5szlGBmjd
However, amplifying (or dampening) feedbacks that kick in as a response to radiative forcing mean that the real-world value—that is, the equilibrium climate sensitivity (ECS)—will be higher (lower) than the ~1°C figure derived from radiative transfer calculations.
So, three critical pieces information are unknown:
1⃣ Exactly how much warming has been man-made (since, let's say, 1950). We still don't know the answer to this because the coefficients that are used to ascribe anthropogenic versus natural forcings are all estimated from computer modeling, not real physical in-situ measurements.
2⃣ The exact value of ECS.
3⃣ Even if global warming is entirely man-made, is it really a net drawback to civilization? Is it a crisis? Is it a problem in the slightest?
To break it down:
• If ECS is <3°C, the climate is insensitive to GHGs, and impacts are exaggerated.
• If ECS is ≥3°C, the climate is sensitive to GHGs, and warming could be a concern.
The IPCC’s “best estimate” of ECS is 3°C with a range of 2-5°C.
🔗https://t.co/8Ntgszr1dC (pp. 44-45)
In 1994, using NASA's real-world bulk atmospheric temperature data, one of my mentors, Dr. John Christy and his co-worker, Dr. Richard McNider from the University of Alabama in Huntsville (UAH), calculated climate sensitivity by removing the effects of El Niño / La Niña and volcanic stratospheric aerosol injection (e.g., El Chichón, 1982; Mt. Pinatubo, 1991).
Christy and McNider found that the human-induced warming rate is about 0.09°C / decade (lower than observations of actual temperature increase). This, by the way, came with the stipulation that unknown mechanisms of internal variability or external forcing are assumed to be zero. I attended a lecture where he talked about this paper in detail.
🔗https://t.co/S2GEmUftKo
They then validated their 1994 findings in McNider & Christy (2017). Specifically, they found a near-identical anthropogenic warming rate of only 0.096°C / decade and a transient climate response (TCR) of 1.10 ± 0.26°K.
🔗https://t.co/zueJLn8V8w / open-access: https://t.co/eLcqeizbRh
Many other recent studies (e.g., Lewis & Curry, 2018; Scafetta, 2021; Spencer & Christy, 2023; Lewis, 2025) have all estimated ECS to be far lower than the IPCC AR6's “best estimate.”
🔗https://t.co/8G0sF8gy2p
🔗https://t.co/5TgNX7c1JN
🔗https://t.co/BxyO1XIbNP
🔗https://t.co/YNQhNajrrO
The jury on ECS is still out. 🤷♂️
What's more, in order to reliably detect anthropogenic influence on the climate system, EEI must be known to the nearest 0.1 W/m² (Von Schuckmann et al., 2016; Gebbie, 2021).
🔗https://t.co/T7SKxidZ4N / open-access: https://t.co/GD45cbhxIT
🔗https://t.co/L6vZKVVpXg
However, the aforementioned Stephens et al. (2012) estimates the EEI to be 0.6 ± 0.4 W/m², which is eight times larger than the anthropogenic detection limits. And the natural top-of-atmosphere (TOA) flux has a 6.6 W/m² margin of error, which is 66 times larger than the detection limits. This range of uncertainty remains in newer estimates, such as Loeb et al. (2021), which estimates EEI to be 1.12 ± 0.48 W/m².
🔗https://t.co/ynRTFd3LWZ
This means that 𝑚𝑜𝑠𝑡 (but not all!) of the observed global warming since 1950 could be natural and scientists would never know for certain (nor would most be humble enough to admit it because the vast majority of academics have high egos). Alternatively, warming could be mostly man-made like alarmists claim, but, even if that is the case, I'll ask again. . .
SO WHAT?
That doesn't mean it is an existential crisis or urgent problem.
The big unknown are CLOUDS. ☁️
Why?
Because (a) cloud albedo has a far greater impact on the atmospheric radiation budget than does CO₂, and (b) how clouds change in response, if at all, to CO₂ is unknown. What's more, cloud cover can (and does) change naturally without mankind's assistance for any number of reasons (e.g., El Niño / La Niña activity; ocean circulation changes; cosmic ray flux; etc.). Even a small decrease in global cloud area fraction (CAF) can more than offset any temperature rise caused by CO₂. Song et al. (2016), for instance, found that,
🗨️ “[𝐴]𝑙𝑡ℎ𝑜𝑢𝑔ℎ 𝑡ℎ𝑒 𝑔𝑟𝑒𝑒𝑛ℎ𝑜𝑢𝑠𝑒 𝑒𝑓𝑓𝑒𝑐𝑡 𝑐𝑎𝑛 𝑏𝑒 𝑒𝑛ℎ𝑎𝑛𝑐𝑒𝑑 𝑏𝑦 𝑖𝑛𝑐𝑟𝑒𝑎𝑠𝑖𝑛𝑔 𝐺𝐻𝐺𝑠 𝑎𝑛𝑑 𝑤𝑎𝑡𝑒𝑟 𝑣𝑎𝑝𝑜𝑟 𝑖𝑛 𝑡ℎ𝑒 𝑎𝑡𝑚𝑜𝑠𝑝ℎ𝑒𝑟𝑒, 𝑖𝑡 𝑐𝑎𝑛 𝑏𝑒 𝑤𝑒𝑎𝑘𝑒𝑛𝑒𝑑 𝑏𝑦 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑖𝑛𝑔 𝑐𝑙𝑜𝑢𝑑𝑠. 𝐼𝑓 𝑡ℎ𝑒𝑠𝑒 𝑡𝑤𝑜 𝑎𝑐𝑡𝑖𝑜𝑛𝑠 𝑜𝑓𝑓𝑠𝑒𝑡 𝑒𝑎𝑐ℎ 𝑜𝑡ℎ𝑒𝑟, 𝑎 ℎ𝑖𝑎𝑡𝑢𝑠 𝑜𝑓 𝑡ℎ𝑒 𝑔𝑙𝑜𝑏𝑎𝑙 𝑔𝑟𝑒𝑒𝑛ℎ𝑜𝑢𝑠𝑒 𝑒𝑓𝑓𝑒𝑐𝑡 𝑤𝑖𝑙𝑙 𝑟𝑒𝑠𝑢𝑙𝑡.”
🔗https://t.co/NHkmfOc08y
I don't deny that global warming is occurring. I never have. I don't even deny an anthropogenic influence on it either. I never have. What I do reject, however, is unchecked alarmism and climate activism, particularly from fellow scientists.
Activism is not science and has no place in science. If you are an activist, you cannot call yourself a scientist because you are not dispassionate and objective. This goes for the vast majority of self-described “climate scientists” who actively use social media and are well-known in the debate. Two notable exceptions on the other side of the spectrum from me, in my opinion, are Drs. Robert Rohde and Paul Williams, both of whom I have always had pleasant interactions with.
I also reject the idea that every weather event needs to be blamed on climate change with a rushed, half-baked attribution study (namely the ones done by the clowns at World Weather Attribution that are often not scientifically rigorous, but get plenty of news media attention by the Associated Press, CNN, The New York Times, and The Washington Post). Attribution “science” is fraudulent anyway because one of the architects behind it admitted to Politico in 2021 that it was designed with the intention of using it in litigation against oil and gas companies.
🔗https://t.co/ETUBune0A8
Conflict of interest much?
It should also be abundantly clear that climate is just a statistical description of the mean and variability of the climate system, including long-term weather. So, a change in climate is just a change in statistics. That is an outcome, not a force or accelerant that causes an extreme weather event to occur.
For what it's worth, I used to be a climate alarmist well before I got my degree in meteorology.
Now that I know a great deal (but not everything and never will) about atmospheric science, my position has evolved to a cooler heads point of view. Perhaps it is not my judgement that's clouded, but rather that of the alarmist arm-wavers who have high trust in both academic institutions and their government officials who spoon-feed them pre-canned talking points on the daily.](https://pbs.twimg.com/media/HL80Ld_XQAAI0WK.jpg)
Olivia
Online
Eilert Bredo Lund
@Eilertbredo
Father and husbound, tweeting at impuls.
Bærum, Norway
Joined August 2010
1.4K Following
895 Followers
29.9K Posts
Frp-leder Sylvi Listhaug hevder statsminister Jonas Gahr Støre bløffer om forbedringer i kjøpekraften under hans regjeringstid, skriver @nettavisen. https://t.co/wqy88wfLO3
@MlleMalin Det var raddisene som var mest mot EU
In yet another Orwellian move, the Government announced in a green paper this week that it wants to decide what news people can and cannot see, with plans to push approved outlets to the top of social media feeds.
Ministers should not be deciding which news sources the public read — especially in an era when three-quarters of under-25s say they get their news from social media.
As written in The Times, “In a state-sponsored regime in which inconvenient news was pushed out of view, would the grooming gangs scandal or the excesses of transgender ideology ever have come to light? You shouldn’t choose to trust everything you read online; but you shouldn’t trust the state to make the choice for you, either”.
This is dystopian.
Read more below in @thetimes 👇
What is my stance on climate change?
Well, I'll lay it out for all of you newcomers. Grab some popcorn! 🍿
First, I do not deny the fact that the Earth has warmed up by ~1.2°C since 1850. However, nobody knows precisely how much because of data quality issues (e.g., uneven surface station distribution; fragmented records, especially outside of the United States; station siting changes; and urban heat island contamination) that have not been (and likely cannot be) removed from the record.
But, I have no doubt that the Earth is [slightly] warmer than it was 175 years ago or that 𝑠𝑜𝑚𝑒 of that warming might be due to carbon dioxide (CO₂) emissions.
Second, contrary to what the online army of alarmist foot soldiers have 𝑚𝑖𝑠𝑙𝑒𝑑 people to believe, there are not really any so-called “fingerprints” that distinguish human-caused global warming from warming caused by other forcings / variability.
Numerous scientific papers claim to have found such a “fingerprint,” but the only evidence that they have presented is that the anomaly of interest is 𝑐𝑜𝑛𝑠𝑖𝑠𝑡𝑒𝑛𝑡 𝑤𝑖𝑡ℎ anthropogenic warming. But these authors fail to mention that said anomaly would also be consistent with natural warming.
Case in point, a reduction in low- and mid-altitude stratiform cloud cover, for instance, would allow more sunlight into the climate system, which would warm the oceans. A warmer ocean—all else being equal—increases the rate of evaporation, which raises the vapor pressure (humidity) contributing to polar amplification and faster land warming than the ocean (e.g., Compo & Sardeshmukh, 2008).
🔗https://t.co/sQurHsN80P / open-access: https://t.co/WVKvLrSV7k
All warming, natural or man-made, results in:
1⃣ Higher latitudes warming faster than both the mid-latitudes and tropics.
2⃣ Land heating up faster than the oceans.
This is just basic physics; look up heat capacity.
Also, an increase in, say, solar forcing would have the same material effect, though we can admittedly likely rule that out as the cause of modern trends because sunspot activity has been declining in recent decades. But the sun does affect our climate in ways that have not really been thoroughly researched because little, if any funding, is ever allocated for such projects by the funding agencies such as the National Science Foundation (NSF).
In any case, the 𝒃𝒆𝒔𝒕 empirical evidence that I have seen to suggest that there is probably [at least some] anthropogenic “fingerprint” on recent temperature increases is stratospheric cooling.
First, you need to understand that in atmospheric physics, heat flux is measured as power—measured in Watts (that is, Joules per second)—standardized per square meter of surface area. This is written as W/m².
Next, the average radiation flux into the atmosphere is on the order of 239 ± 3.3 W/m² of absorbed solar radiation (ASR) averaged over a year (Stephens et al., 2012). This means that in order for the Earth's surface to maintain a constant temperature, the surface must emit 239.7 ± 3.3 W/m² back to outer space.
🔗https://t.co/5z5iMdazRB / open-access: https://t.co/51Ys5w8BWj
Global warming theory maintains the direct radiative forcing from doubling atmospheric CO₂ levels (often noted as RF 2×CO₂) is 3.7 ± 0.4 W/m² (e.g., IPCC TAR, 2007). That means that the net outgoing longwave radiation (OLR) to outer space is reduced by 3.7 W/m², which creates an Earth energy imbalance (EEI), which leads to a slight warming tendency in the troposphere (surface to ~13 km altitude).
🔗https://t.co/0JkXIQRGDH (p. 357)
In the stratosphere (~13-50 km altitude), this causes a cooling tendency because less infrared radiation (IR) flux is moving upward from below. These relationships were first demonstrated in Manabe & Strickler (1964).
🔗https://t.co/JNaXP7nUC9
NASA satellite measurements indicate that cooling in the stratosphere has been observed since the late 1970s, although there has been very little cooling over the last 25 years, all the while the troposphere has continued to warm.
🔗https://t.co/hT0Oxwm2Io
That means that most of the warming observed since 2000 is likely natural OR perhaps partly caused by a reduction in stratospheric sulfate aerosol concentrations, an artifact of particulate aerosol pollution regulations in recent years.
But, yes, I would agree with most scientists that the cooling observed in the stratosphere, at least that from the 1970s to 2000, is most likely a result of CO₂ forcing.
So what?
What happens down here in the lower atmosphere in response to CO₂ forcing is a lot more nuanced.
Why?
Because here in the troposphere, there are feedbacks (largely cloud-related) and precipitation processes that affect the atmospheric radiation budget far more than CO₂. And how exactly clouds respond to warming in the troposphere, if at all, is not very well understood, and by extension, not well-modeled.
What we do know, theoretically speaking, is that the direct warming effect of RF 2×CO₂ is actually very small. Specifically, it is on the order of ~1°C (e.g., Wijngaarden & Happer, 2020).
🔗https://t.co/y5szlGBmjd
However, amplifying (or dampening) feedbacks that kick in as a response to radiative forcing mean that the real-world value—that is, the equilibrium climate sensitivity (ECS)—will be higher (lower) than the ~1°C figure derived from radiative transfer calculations.
So, three critical pieces information are unknown:
1⃣ Exactly how much warming has been man-made (since, let's say, 1950). We still don't know the answer to this because the coefficients that are used to ascribe anthropogenic versus natural forcings are all estimated from computer modeling, not real physical in-situ measurements.
2⃣ The exact value of ECS.
3⃣ Even if global warming is entirely man-made, is it really a net drawback to civilization? Is it a crisis? Is it a problem in the slightest?
To break it down:
• If ECS is <3°C, the climate is insensitive to GHGs, and impacts are exaggerated.
• If ECS is ≥3°C, the climate is sensitive to GHGs, and warming could be a concern.
The IPCC’s “best estimate” of ECS is 3°C with a range of 2-5°C.
🔗https://t.co/8Ntgszr1dC (pp. 44-45)
In 1994, using NASA's real-world bulk atmospheric temperature data, one of my mentors, Dr. John Christy and his co-worker, Dr. Richard McNider from the University of Alabama in Huntsville (UAH), calculated climate sensitivity by removing the effects of El Niño / La Niña and volcanic stratospheric aerosol injection (e.g., El Chichón, 1982; Mt. Pinatubo, 1991).
Christy and McNider found that the human-induced warming rate is about 0.09°C / decade (lower than observations of actual temperature increase). This, by the way, came with the stipulation that unknown mechanisms of internal variability or external forcing are assumed to be zero. I attended a lecture where he talked about this paper in detail.
🔗https://t.co/S2GEmUftKo
They then validated their 1994 findings in McNider & Christy (2017). Specifically, they found a near-identical anthropogenic warming rate of only 0.096°C / decade and a transient climate response (TCR) of 1.10 ± 0.26°K.
🔗https://t.co/zueJLn8V8w / open-access: https://t.co/eLcqeizbRh
Many other recent studies (e.g., Lewis & Curry, 2018; Scafetta, 2021; Spencer & Christy, 2023; Lewis, 2025) have all estimated ECS to be far lower than the IPCC AR6's “best estimate.”
🔗https://t.co/8G0sF8gy2p
🔗https://t.co/5TgNX7c1JN
🔗https://t.co/BxyO1XIbNP
🔗https://t.co/YNQhNajrrO
The jury on ECS is still out. 🤷♂️
What's more, in order to reliably detect anthropogenic influence on the climate system, EEI must be known to the nearest 0.1 W/m² (Von Schuckmann et al., 2016; Gebbie, 2021).
🔗https://t.co/T7SKxidZ4N / open-access: https://t.co/GD45cbhxIT
🔗https://t.co/L6vZKVVpXg
However, the aforementioned Stephens et al. (2012) estimates the EEI to be 0.6 ± 0.4 W/m², which is eight times larger than the anthropogenic detection limits. And the natural top-of-atmosphere (TOA) flux has a 6.6 W/m² margin of error, which is 66 times larger than the detection limits. This range of uncertainty remains in newer estimates, such as Loeb et al. (2021), which estimates EEI to be 1.12 ± 0.48 W/m².
🔗https://t.co/ynRTFd3LWZ
This means that 𝑚𝑜𝑠𝑡 (but not all!) of the observed global warming since 1950 could be natural and scientists would never know for certain (nor would most be humble enough to admit it because the vast majority of academics have high egos). Alternatively, warming could be mostly man-made like alarmists claim, but, even if that is the case, I'll ask again. . .
SO WHAT?
That doesn't mean it is an existential crisis or urgent problem.
The big unknown are CLOUDS. ☁️
Why?
Because (a) cloud albedo has a far greater impact on the atmospheric radiation budget than does CO₂, and (b) how clouds change in response, if at all, to CO₂ is unknown. What's more, cloud cover can (and does) change naturally without mankind's assistance for any number of reasons (e.g., El Niño / La Niña activity; ocean circulation changes; cosmic ray flux; etc.). Even a small decrease in global cloud area fraction (CAF) can more than offset any temperature rise caused by CO₂. Song et al. (2016), for instance, found that,
🗨️ “[𝐴]𝑙𝑡ℎ𝑜𝑢𝑔ℎ 𝑡ℎ𝑒 𝑔𝑟𝑒𝑒𝑛ℎ𝑜𝑢𝑠𝑒 𝑒𝑓𝑓𝑒𝑐𝑡 𝑐𝑎𝑛 𝑏𝑒 𝑒𝑛ℎ𝑎𝑛𝑐𝑒𝑑 𝑏𝑦 𝑖𝑛𝑐𝑟𝑒𝑎𝑠𝑖𝑛𝑔 𝐺𝐻𝐺𝑠 𝑎𝑛𝑑 𝑤𝑎𝑡𝑒𝑟 𝑣𝑎𝑝𝑜𝑟 𝑖𝑛 𝑡ℎ𝑒 𝑎𝑡𝑚𝑜𝑠𝑝ℎ𝑒𝑟𝑒, 𝑖𝑡 𝑐𝑎𝑛 𝑏𝑒 𝑤𝑒𝑎𝑘𝑒𝑛𝑒𝑑 𝑏𝑦 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑖𝑛𝑔 𝑐𝑙𝑜𝑢𝑑𝑠. 𝐼𝑓 𝑡ℎ𝑒𝑠𝑒 𝑡𝑤𝑜 𝑎𝑐𝑡𝑖𝑜𝑛𝑠 𝑜𝑓𝑓𝑠𝑒𝑡 𝑒𝑎𝑐ℎ 𝑜𝑡ℎ𝑒𝑟, 𝑎 ℎ𝑖𝑎𝑡𝑢𝑠 𝑜𝑓 𝑡ℎ𝑒 𝑔𝑙𝑜𝑏𝑎𝑙 𝑔𝑟𝑒𝑒𝑛ℎ𝑜𝑢𝑠𝑒 𝑒𝑓𝑓𝑒𝑐𝑡 𝑤𝑖𝑙𝑙 𝑟𝑒𝑠𝑢𝑙𝑡.”
🔗https://t.co/NHkmfOc08y
I don't deny that global warming is occurring. I never have. I don't even deny an anthropogenic influence on it either. I never have. What I do reject, however, is unchecked alarmism and climate activism, particularly from fellow scientists.
Activism is not science and has no place in science. If you are an activist, you cannot call yourself a scientist because you are not dispassionate and objective. This goes for the vast majority of self-described “climate scientists” who actively use social media and are well-known in the debate. Two notable exceptions on the other side of the spectrum from me, in my opinion, are Drs. Robert Rohde and Paul Williams, both of whom I have always had pleasant interactions with.
I also reject the idea that every weather event needs to be blamed on climate change with a rushed, half-baked attribution study (namely the ones done by the clowns at World Weather Attribution that are often not scientifically rigorous, but get plenty of news media attention by the Associated Press, CNN, The New York Times, and The Washington Post). Attribution “science” is fraudulent anyway because one of the architects behind it admitted to Politico in 2021 that it was designed with the intention of using it in litigation against oil and gas companies.
🔗https://t.co/ETUBune0A8
Conflict of interest much?
It should also be abundantly clear that climate is just a statistical description of the mean and variability of the climate system, including long-term weather. So, a change in climate is just a change in statistics. That is an outcome, not a force or accelerant that causes an extreme weather event to occur.
For what it's worth, I used to be a climate alarmist well before I got my degree in meteorology.
Now that I know a great deal (but not everything and never will) about atmospheric science, my position has evolved to a cooler heads point of view. Perhaps it is not my judgement that's clouded, but rather that of the alarmist arm-wavers who have high trust in both academic institutions and their government officials who spoon-feed them pre-canned talking points on the daily.
![ChrisMartzWX's tweet photo. What is my stance on climate change?
Well, I'll lay it out for all of you newcomers. Grab some popcorn! 🍿
First, I do not deny the fact that the Earth has warmed up by ~1.2°C since 1850. However, nobody knows precisely how much because of data quality issues (e.g., uneven surface station distribution; fragmented records, especially outside of the United States; station siting changes; and urban heat island contamination) that have not been (and likely cannot be) removed from the record.
But, I have no doubt that the Earth is [slightly] warmer than it was 175 years ago or that 𝑠𝑜𝑚𝑒 of that warming might be due to carbon dioxide (CO₂) emissions.
Second, contrary to what the online army of alarmist foot soldiers have 𝑚𝑖𝑠𝑙𝑒𝑑 people to believe, there are not really any so-called “fingerprints” that distinguish human-caused global warming from warming caused by other forcings / variability.
Numerous scientific papers claim to have found such a “fingerprint,” but the only evidence that they have presented is that the anomaly of interest is 𝑐𝑜𝑛𝑠𝑖𝑠𝑡𝑒𝑛𝑡 𝑤𝑖𝑡ℎ anthropogenic warming. But these authors fail to mention that said anomaly would also be consistent with natural warming.
Case in point, a reduction in low- and mid-altitude stratiform cloud cover, for instance, would allow more sunlight into the climate system, which would warm the oceans. A warmer ocean—all else being equal—increases the rate of evaporation, which raises the vapor pressure (humidity) contributing to polar amplification and faster land warming than the ocean (e.g., Compo & Sardeshmukh, 2008).
🔗https://t.co/sQurHsN80P / open-access: https://t.co/WVKvLrSV7k
All warming, natural or man-made, results in:
1⃣ Higher latitudes warming faster than both the mid-latitudes and tropics.
2⃣ Land heating up faster than the oceans.
This is just basic physics; look up heat capacity.
Also, an increase in, say, solar forcing would have the same material effect, though we can admittedly likely rule that out as the cause of modern trends because sunspot activity has been declining in recent decades. But the sun does affect our climate in ways that have not really been thoroughly researched because little, if any funding, is ever allocated for such projects by the funding agencies such as the National Science Foundation (NSF).
In any case, the 𝒃𝒆𝒔𝒕 empirical evidence that I have seen to suggest that there is probably [at least some] anthropogenic “fingerprint” on recent temperature increases is stratospheric cooling.
First, you need to understand that in atmospheric physics, heat flux is measured as power—measured in Watts (that is, Joules per second)—standardized per square meter of surface area. This is written as W/m².
Next, the average radiation flux into the atmosphere is on the order of 239 ± 3.3 W/m² of absorbed solar radiation (ASR) averaged over a year (Stephens et al., 2012). This means that in order for the Earth's surface to maintain a constant temperature, the surface must emit 239.7 ± 3.3 W/m² back to outer space.
🔗https://t.co/5z5iMdazRB / open-access: https://t.co/51Ys5w8BWj
Global warming theory maintains the direct radiative forcing from doubling atmospheric CO₂ levels (often noted as RF 2×CO₂) is 3.7 ± 0.4 W/m² (e.g., IPCC TAR, 2007). That means that the net outgoing longwave radiation (OLR) to outer space is reduced by 3.7 W/m², which creates an Earth energy imbalance (EEI), which leads to a slight warming tendency in the troposphere (surface to ~13 km altitude).
🔗https://t.co/0JkXIQRGDH (p. 357)
In the stratosphere (~13-50 km altitude), this causes a cooling tendency because less infrared radiation (IR) flux is moving upward from below. These relationships were first demonstrated in Manabe & Strickler (1964).
🔗https://t.co/JNaXP7nUC9
NASA satellite measurements indicate that cooling in the stratosphere has been observed since the late 1970s, although there has been very little cooling over the last 25 years, all the while the troposphere has continued to warm.
🔗https://t.co/hT0Oxwm2Io
That means that most of the warming observed since 2000 is likely natural OR perhaps partly caused by a reduction in stratospheric sulfate aerosol concentrations, an artifact of particulate aerosol pollution regulations in recent years.
But, yes, I would agree with most scientists that the cooling observed in the stratosphere, at least that from the 1970s to 2000, is most likely a result of CO₂ forcing.
So what?
What happens down here in the lower atmosphere in response to CO₂ forcing is a lot more nuanced.
Why?
Because here in the troposphere, there are feedbacks (largely cloud-related) and precipitation processes that affect the atmospheric radiation budget far more than CO₂. And how exactly clouds respond to warming in the troposphere, if at all, is not very well understood, and by extension, not well-modeled.
What we do know, theoretically speaking, is that the direct warming effect of RF 2×CO₂ is actually very small. Specifically, it is on the order of ~1°C (e.g., Wijngaarden & Happer, 2020).
🔗https://t.co/y5szlGBmjd
However, amplifying (or dampening) feedbacks that kick in as a response to radiative forcing mean that the real-world value—that is, the equilibrium climate sensitivity (ECS)—will be higher (lower) than the ~1°C figure derived from radiative transfer calculations.
So, three critical pieces information are unknown:
1⃣ Exactly how much warming has been man-made (since, let's say, 1950). We still don't know the answer to this because the coefficients that are used to ascribe anthropogenic versus natural forcings are all estimated from computer modeling, not real physical in-situ measurements.
2⃣ The exact value of ECS.
3⃣ Even if global warming is entirely man-made, is it really a net drawback to civilization? Is it a crisis? Is it a problem in the slightest?
To break it down:
• If ECS is <3°C, the climate is insensitive to GHGs, and impacts are exaggerated.
• If ECS is ≥3°C, the climate is sensitive to GHGs, and warming could be a concern.
The IPCC’s “best estimate” of ECS is 3°C with a range of 2-5°C.
🔗https://t.co/8Ntgszr1dC (pp. 44-45)
In 1994, using NASA's real-world bulk atmospheric temperature data, one of my mentors, Dr. John Christy and his co-worker, Dr. Richard McNider from the University of Alabama in Huntsville (UAH), calculated climate sensitivity by removing the effects of El Niño / La Niña and volcanic stratospheric aerosol injection (e.g., El Chichón, 1982; Mt. Pinatubo, 1991).
Christy and McNider found that the human-induced warming rate is about 0.09°C / decade (lower than observations of actual temperature increase). This, by the way, came with the stipulation that unknown mechanisms of internal variability or external forcing are assumed to be zero. I attended a lecture where he talked about this paper in detail.
🔗https://t.co/S2GEmUftKo
They then validated their 1994 findings in McNider & Christy (2017). Specifically, they found a near-identical anthropogenic warming rate of only 0.096°C / decade and a transient climate response (TCR) of 1.10 ± 0.26°K.
🔗https://t.co/zueJLn8V8w / open-access: https://t.co/eLcqeizbRh
Many other recent studies (e.g., Lewis & Curry, 2018; Scafetta, 2021; Spencer & Christy, 2023; Lewis, 2025) have all estimated ECS to be far lower than the IPCC AR6's “best estimate.”
🔗https://t.co/8G0sF8gy2p
🔗https://t.co/5TgNX7c1JN
🔗https://t.co/BxyO1XIbNP
🔗https://t.co/YNQhNajrrO
The jury on ECS is still out. 🤷♂️
What's more, in order to reliably detect anthropogenic influence on the climate system, EEI must be known to the nearest 0.1 W/m² (Von Schuckmann et al., 2016; Gebbie, 2021).
🔗https://t.co/T7SKxidZ4N / open-access: https://t.co/GD45cbhxIT
🔗https://t.co/L6vZKVVpXg
However, the aforementioned Stephens et al. (2012) estimates the EEI to be 0.6 ± 0.4 W/m², which is eight times larger than the anthropogenic detection limits. And the natural top-of-atmosphere (TOA) flux has a 6.6 W/m² margin of error, which is 66 times larger than the detection limits. This range of uncertainty remains in newer estimates, such as Loeb et al. (2021), which estimates EEI to be 1.12 ± 0.48 W/m².
🔗https://t.co/ynRTFd3LWZ
This means that 𝑚𝑜𝑠𝑡 (but not all!) of the observed global warming since 1950 could be natural and scientists would never know for certain (nor would most be humble enough to admit it because the vast majority of academics have high egos). Alternatively, warming could be mostly man-made like alarmists claim, but, even if that is the case, I'll ask again. . .
SO WHAT?
That doesn't mean it is an existential crisis or urgent problem.
The big unknown are CLOUDS. ☁️
Why?
Because (a) cloud albedo has a far greater impact on the atmospheric radiation budget than does CO₂, and (b) how clouds change in response, if at all, to CO₂ is unknown. What's more, cloud cover can (and does) change naturally without mankind's assistance for any number of reasons (e.g., El Niño / La Niña activity; ocean circulation changes; cosmic ray flux; etc.). Even a small decrease in global cloud area fraction (CAF) can more than offset any temperature rise caused by CO₂. Song et al. (2016), for instance, found that,
🗨️ “[𝐴]𝑙𝑡ℎ𝑜𝑢𝑔ℎ 𝑡ℎ𝑒 𝑔𝑟𝑒𝑒𝑛ℎ𝑜𝑢𝑠𝑒 𝑒𝑓𝑓𝑒𝑐𝑡 𝑐𝑎𝑛 𝑏𝑒 𝑒𝑛ℎ𝑎𝑛𝑐𝑒𝑑 𝑏𝑦 𝑖𝑛𝑐𝑟𝑒𝑎𝑠𝑖𝑛𝑔 𝐺𝐻𝐺𝑠 𝑎𝑛𝑑 𝑤𝑎𝑡𝑒𝑟 𝑣𝑎𝑝𝑜𝑟 𝑖𝑛 𝑡ℎ𝑒 𝑎𝑡𝑚𝑜𝑠𝑝ℎ𝑒𝑟𝑒, 𝑖𝑡 𝑐𝑎𝑛 𝑏𝑒 𝑤𝑒𝑎𝑘𝑒𝑛𝑒𝑑 𝑏𝑦 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑖𝑛𝑔 𝑐𝑙𝑜𝑢𝑑𝑠. 𝐼𝑓 𝑡ℎ𝑒𝑠𝑒 𝑡𝑤𝑜 𝑎𝑐𝑡𝑖𝑜𝑛𝑠 𝑜𝑓𝑓𝑠𝑒𝑡 𝑒𝑎𝑐ℎ 𝑜𝑡ℎ𝑒𝑟, 𝑎 ℎ𝑖𝑎𝑡𝑢𝑠 𝑜𝑓 𝑡ℎ𝑒 𝑔𝑙𝑜𝑏𝑎𝑙 𝑔𝑟𝑒𝑒𝑛ℎ𝑜𝑢𝑠𝑒 𝑒𝑓𝑓𝑒𝑐𝑡 𝑤𝑖𝑙𝑙 𝑟𝑒𝑠𝑢𝑙𝑡.”
🔗https://t.co/NHkmfOc08y
I don't deny that global warming is occurring. I never have. I don't even deny an anthropogenic influence on it either. I never have. What I do reject, however, is unchecked alarmism and climate activism, particularly from fellow scientists.
Activism is not science and has no place in science. If you are an activist, you cannot call yourself a scientist because you are not dispassionate and objective. This goes for the vast majority of self-described “climate scientists” who actively use social media and are well-known in the debate. Two notable exceptions on the other side of the spectrum from me, in my opinion, are Drs. Robert Rohde and Paul Williams, both of whom I have always had pleasant interactions with.
I also reject the idea that every weather event needs to be blamed on climate change with a rushed, half-baked attribution study (namely the ones done by the clowns at World Weather Attribution that are often not scientifically rigorous, but get plenty of news media attention by the Associated Press, CNN, The New York Times, and The Washington Post). Attribution “science” is fraudulent anyway because one of the architects behind it admitted to Politico in 2021 that it was designed with the intention of using it in litigation against oil and gas companies.
🔗https://t.co/ETUBune0A8
Conflict of interest much?
It should also be abundantly clear that climate is just a statistical description of the mean and variability of the climate system, including long-term weather. So, a change in climate is just a change in statistics. That is an outcome, not a force or accelerant that causes an extreme weather event to occur.
For what it's worth, I used to be a climate alarmist well before I got my degree in meteorology.
Now that I know a great deal (but not everything and never will) about atmospheric science, my position has evolved to a cooler heads point of view. Perhaps it is not my judgement that's clouded, but rather that of the alarmist arm-wavers who have high trust in both academic institutions and their government officials who spoon-feed them pre-canned talking points on the daily.](https://pbs.twimg.com/media/HL80_WOWkAAFtJA.png)
Many people claim that so-called “climate change” is due to human activities on planet Earth, but the facts tell a more complex story.
First, there is no permanent state of climate. It is always in flux, changing due to complex natural factors – something we clearly see throughout Earth’s history.
Carbon dioxide (CO₂) currently makes up about 0.04% of Earth’s atmosphere by volume (more precisely, roughly 420–425 parts per million, or ppm).
The biosphere – through plant and animal respiration, decomposition, soil processes, and wildfires – accounts for roughly 97% of the total CO₂ exchanged with the atmosphere each year.
Human activities account for about 3%. Humans emit about 40 gigatons of CO₂ annually, which corresponds to an increase of roughly 2 parts per million (ppm) in atmospheric CO₂ concentration per year.
To put that into perspective: in a sample of 1,000,000 air molecules, only 2 of them would be CO₂ emitted directly from human activities.
How can anyone, with a straight face, claim that those two molecules of CO₂ out of 1,000,000 molecules of atmosphere are responsible for climate change?
Frp har sjekket Aps utsagn om at vi har fått økt kjøpekraft og funnet ut at det er feil, og SSB er enig. Ap har nemlig utelatt lånekostnader fra regnestykket.
Listhaug: "Å ikke ta med lånekostnader blir helt feil. Det er en stor utgift for svært mange og de tallene er ikke med i røverhistorien til Støre. Mange nordmenn har ingen opplevelse av at det går bedre økonomisk. Regjeringen bør bruke mindre tid på å pynte på virkeligheten, og mer tid på å bedre vanlige folks økonomi."
Innvandrere ber meg ta livet av meg og sier de skal voldta meg. Jeg legger ut skjermbilder av meldingene på Instagram. Instagram fjerner innlegget mitt for brudd på reglene. 🙃
Dette har nå skjedd to ganger.
Første gang klagde jeg og innlegget ble gjenopprettet fordi det faktisk ikke var noe regelbrudd.
Andre gang ble klagen avslått, og innlegget ble fjernet for godt.
Så den er grei, Instagram. De kan visst sende hva de vil i DM. Grensen deres går først når jeg deler det.
@LBirkelund Kan vi starte «vi som bryr oss klassekamp 1»
@HeleneTveit1 Hvor er pride
@enterfx To little, crisis , famine, now to much, crisis, price might drop.
@WEschenbach Its a cult by now
@visegrad24 Take the phobia out, it’s real
I Sverige har de den samme berøringsangsten som i Norge. Venstresiden elsker å snakke om hat, vold og sinne mot homofile men de klarer ikke svare på hvem som utfører det.
@RuneSolberg_111 Kanskje VG burde etterforsket saken
Rettsstaten Norge!!
Jeg tror mer på Elise enn på AS Norge.
For et land vi har blitt.
Apekatter og klovner over hele linja...
🙈🙉🙊🤡🤡🤡
Jeg oppdaget jo at losjen hadde vært litt nærmere enn jeg trodde her forleden og tenkte at jeg skulle roe reka litt.
Men WTF, saueflokken lar dem jo herje som de vil med oss...
Det er ikke greit!!
Skjerp dere @Frilurerlosjen !!
Here's one of Michael Crichton's very finest quotes, especially applicable to climate "science":
"I want to pause here and talk about this notion of consensus, and the rise of what has been called consensus science.
I regard consensus science as an extremely pernicious development that ought to be stopped cold in its tracks. Historically, the claim of consensus has been the first refuge of scoundrels; it is a way to avoid debate by claiming that the matter is already settled.
Whenever you hear the consensus of scientists agrees on something or other, reach for your wallet, because you’re being had.
Let’s be clear: the work of science has nothing whatever to do with consensus. Consensus is the business of politics. Science, on the contrary, requires only one investigator who happens to be right ... In science, consensus is irrelevant."
Best to everyone,
w.
AP climate propagandist @johnleicester seems to hope that of he keeps chanting World Weather Attribution fraud, it will become science:
"A new study from the World Weather Attribution, a Europe-based collaboration of scientists, reported Friday that the record-breaking heat and humidity in Europe this past week would not have been possible without climate change. The rapid study found that the heat would have been virtually impossible just five decades ago, and is 200 times more likely today than it would have been 20 years ago."🙄
The @WWAtttibution con is that atmospheric CO2 drives weather. If that was science, WWA would be able to predict something based on it. But WWA never has. Instead, it just makes up untestable and unverifiable probabilities of past weather events. AP readers don't know how scientifically bankrupt WWA is because propaganda hacks like Leicester never present other views. The AP has been paid millions of dollars by climate communist groups to promote the climate hoax. And that's what it does.
https://t.co/LjSqbGNYxG
@Lykten_no https://t.co/IYFQP1H8gw
I don't normaly ask people to share content but we need your help to put pressure on our Labour Party run Goverment. Please share this wide!
In Norwegian mosques and Islamic centers like DIKSIN, children and teenagers are forced into 24-hour Qur'an schools with accommodation where the days are filled with Qur'an
lessons, prayer and mosque washing from early morning until late at night. A 19-year-old who escaped the regime tells of a closed Muslim system that the government has allowed to prevail for years – where Islam gives women zero right to protest or say no.
The Goverment demanded a ban on such coercive arrangements six years ago, but the authorities said no in order to “protect human rights”. DIKSIN denies everything and calls it voluntary. Lies! This is state-sanctioned child oppression and a parallel society in the middle of Norway. 😡🕌🚫
Program: NRK Dagsrevyen, 27.06.2026
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