Very helpful, and resolves my own uncertainty about the matter.
Regarding the deniers, my favorite of your writings was a sneak-preview of an IPCC report that was embargoed for a few more days. You previewed the contents of the report this way: “You morons, we’ve been telling you this for 30 years ...” Got a great chuckle out of that.
Dr. Dressler, thank you very much for using your time to post this. For me, a great learning experience. My previous discussions with a physical oceanographer leads me to conclude that most of the environmental risks, damages and loss of lives, was due to tsunamis, near and very distant, and--- "shockwaves", detected as faraway as Europe. Rather than listing individual citations, here is a pretty good summary with great graphics: https://www.theclimatebrink.com/p/the-climate-impact-of-the-hunga-tonga . cheers
Thank you this is so helpful. I got the Hunga Tonga must be the cause of the July heat just yesterday from 'deniers'
They also said that because the July increase was so big it couldn't have been caused by human emissions of co2 because that has a gradual effect on rising temperatures! Like the body the climate system must be interconnected. Melting ice, el Nino/la nina will interplay to cause sudden jumps. I am sure you could say this in a much more convincing sounding way?
The climate is a combination of two factors. First, there's a slow and steady trend that driven by human emissions of CO2 and other GHGs. On top of that is short-term variability, which can be imagined as the bumps and dips on that slope. Sometimes, these short-term changes can align with the long-term trend, and when that happens, we can witness significant spikes in temperature in just a short span.
Thank you for this! I am glad I found your newsletter. I am teaching Intro to Earth Science this fall and am adding this to our volcanoes reading list. I appreciate the relevant, approachable style and am sure students will too.
I also would recommend video presentations by Dr. Jessica Tierney for you and your class. She is a paleoclimatologist at the University of Arizona. Her story about volcanoes is quite simple. CO2 gets buried in the rocks, plate tectonics cause volcanoes and they eject CO2 into the atmosphere causing some of the hottest climates in earth’s history. Here is an example, https://www.youtube.com/watch?v=eFNYrT-ArWQ .
I was doing research on a paleontology project a few years ago and remember reading that volcanoes likely warmed the planet during prehistoric times because the volume was so much greater. Does this track with what scientists believe?
Yes. But those events weren't really volcanoes, they were much larger things called magmatic provinces that kept pouring out magma for a very long time. The worst of them (the end-Permian) erupted in a region with with a lot of carbonate rocks and especially coal, and went on for two million years. It killed almost everything. Iceland may be a current small example of a magmatic province, but fortunately isn't pumping out much CO2. But outside of those fortunately very rare large events, IIRC the most recent significant one having occurred in the Pacific Northwest (Columbia basalts) about 16 million years ago and causing a brief global heating spike (the mid-Miocene climate optimum), volcanoes and the mid-ocean ridges (Iceland is part of one) continue to play a key role in keeping CO2 levels as high as they are. Equally fortunately their activity doesn't vary much globally. Long, long ago (billions of years), there was indeed a lot more magmatic activity, the Earth having started out as a ball of magma after a huge planetary collision that also created the moon, but again fortunately that's irrelevant to what's happening in the present. Wikipedia has good articles with the details.
What a fantastic reply, and thanks for pointing me towards more detailed articles. Yeah I think it was something I must've read in like the Economist or something where I got the basics but not the details.
Nice article, well written. I have a question that I'm hoping you can clear up. Since the lapse rate in the stratosphere is of the opposite sign to that in the troposphere, why isn't the long wavelength forcing in the Solomon plot negative? In other words, why isn't water vapor in the stratosphere cooling rather than warming? Thanks in advance.
The stratosphere is in radiative equilibrium. If you add a radiator to the stratosphere (water vapor, CO2), you increase downward radiation and warm the lower atmosphere. In the lower atmosphere, which is in radiative-convective equilibrium, you're quite right that, if the atmosphere warmed with altitude, you'd get an anti-greenhouse effect. That occurs b/c the temperature of the lower atmosphere is tied together by convection. This may not be super clear, but I did a video about that: https://youtu.be/4PAbm1u1IVg
Thanks Andrew. Yes, I've seen your excellent video before which is partly the reason why I'm asking this question. Just to make sure I understand what you're saying -- as with CO2 in the stratosphere are you saying that locally water vapor in the stratosphere may have a cooling effect, but in the troposphere that additional water vapor in the stratosphere is actually warming because of the downward radiation? Is the long wavelength radiation corresponding to water vapor --- in the stratosphere -- optically thick or not?
Yes: water vapor added to the stratosphere cools the stratosphere and warms the troposphere. AFAIK at most if not all wavelengths the stratosphere is optically thin in water's bands.
Is one of the papers you referenced from NCAR (National Center for Atmospheric Research)? I have seen that being referenced in tweets claiming eruption is having a "warming effect".
FYI - I did investigate the authors of the references and found these authors from the third article (https://www.nature.com/articles/s43247-022-00580-w) include researchers from the National Center for Atmospheric Research, Boulder, USA
Dr Dessler, I would like to thank you for the climate brink. It has been so much fun reading your posts. The first one I read was the carbon capture one and I’ve been hooked ever since.
Here's a relevant question: To what extent does atmospheric SO2, from volcanoes or fossil fuel combustion, react with OH to an extent that the oxidative capacity of the atmosphere is reduced? I have seen at least one paleoclimate paper that suggests that increased volcanic SO2 in the past reduced atmospheric OH, increased the lifetime of atmospheric methane, and forced greater warming.
You can't see the woods for the trees. There is one Sun, one planet, one atmosphere, one ocean and one climate system - chaotic and complex as it is.
Climate science is putting the jigsaw pieces together. Some pieces are missing but the picture and story it tells are clear. Certainly to - for all intents and purposes - all climate scientists, the global community of scientists and world governments.
DISCLAIMER: I believe science gives us our best view of reality and science ultimately depends on the judgement of experts. For example, Andrew Dessler and Zeke Hausfather.
Very helpful, and resolves my own uncertainty about the matter.
Regarding the deniers, my favorite of your writings was a sneak-preview of an IPCC report that was embargoed for a few more days. You previewed the contents of the report this way: “You morons, we’ve been telling you this for 30 years ...” Got a great chuckle out of that.
Dr. Dressler, thank you very much for using your time to post this. For me, a great learning experience. My previous discussions with a physical oceanographer leads me to conclude that most of the environmental risks, damages and loss of lives, was due to tsunamis, near and very distant, and--- "shockwaves", detected as faraway as Europe. Rather than listing individual citations, here is a pretty good summary with great graphics: https://www.theclimatebrink.com/p/the-climate-impact-of-the-hunga-tonga . cheers
Thank you this is so helpful. I got the Hunga Tonga must be the cause of the July heat just yesterday from 'deniers'
They also said that because the July increase was so big it couldn't have been caused by human emissions of co2 because that has a gradual effect on rising temperatures! Like the body the climate system must be interconnected. Melting ice, el Nino/la nina will interplay to cause sudden jumps. I am sure you could say this in a much more convincing sounding way?
Thank you
Jo
The climate is a combination of two factors. First, there's a slow and steady trend that driven by human emissions of CO2 and other GHGs. On top of that is short-term variability, which can be imagined as the bumps and dips on that slope. Sometimes, these short-term changes can align with the long-term trend, and when that happens, we can witness significant spikes in temperature in just a short span.
Thank you Andrew, I was correct, a great summation!
Jo
Thank you for this! I am glad I found your newsletter. I am teaching Intro to Earth Science this fall and am adding this to our volcanoes reading list. I appreciate the relevant, approachable style and am sure students will too.
Thank you!
I also would recommend video presentations by Dr. Jessica Tierney for you and your class. She is a paleoclimatologist at the University of Arizona. Her story about volcanoes is quite simple. CO2 gets buried in the rocks, plate tectonics cause volcanoes and they eject CO2 into the atmosphere causing some of the hottest climates in earth’s history. Here is an example, https://www.youtube.com/watch?v=eFNYrT-ArWQ .
I was doing research on a paleontology project a few years ago and remember reading that volcanoes likely warmed the planet during prehistoric times because the volume was so much greater. Does this track with what scientists believe?
Yes. But those events weren't really volcanoes, they were much larger things called magmatic provinces that kept pouring out magma for a very long time. The worst of them (the end-Permian) erupted in a region with with a lot of carbonate rocks and especially coal, and went on for two million years. It killed almost everything. Iceland may be a current small example of a magmatic province, but fortunately isn't pumping out much CO2. But outside of those fortunately very rare large events, IIRC the most recent significant one having occurred in the Pacific Northwest (Columbia basalts) about 16 million years ago and causing a brief global heating spike (the mid-Miocene climate optimum), volcanoes and the mid-ocean ridges (Iceland is part of one) continue to play a key role in keeping CO2 levels as high as they are. Equally fortunately their activity doesn't vary much globally. Long, long ago (billions of years), there was indeed a lot more magmatic activity, the Earth having started out as a ball of magma after a huge planetary collision that also created the moon, but again fortunately that's irrelevant to what's happening in the present. Wikipedia has good articles with the details.
What a fantastic reply, and thanks for pointing me towards more detailed articles. Yeah I think it was something I must've read in like the Economist or something where I got the basics but not the details.
Nice article, well written. I have a question that I'm hoping you can clear up. Since the lapse rate in the stratosphere is of the opposite sign to that in the troposphere, why isn't the long wavelength forcing in the Solomon plot negative? In other words, why isn't water vapor in the stratosphere cooling rather than warming? Thanks in advance.
The stratosphere is in radiative equilibrium. If you add a radiator to the stratosphere (water vapor, CO2), you increase downward radiation and warm the lower atmosphere. In the lower atmosphere, which is in radiative-convective equilibrium, you're quite right that, if the atmosphere warmed with altitude, you'd get an anti-greenhouse effect. That occurs b/c the temperature of the lower atmosphere is tied together by convection. This may not be super clear, but I did a video about that: https://youtu.be/4PAbm1u1IVg
Thanks Andrew. Yes, I've seen your excellent video before which is partly the reason why I'm asking this question. Just to make sure I understand what you're saying -- as with CO2 in the stratosphere are you saying that locally water vapor in the stratosphere may have a cooling effect, but in the troposphere that additional water vapor in the stratosphere is actually warming because of the downward radiation? Is the long wavelength radiation corresponding to water vapor --- in the stratosphere -- optically thick or not?
Yes: water vapor added to the stratosphere cools the stratosphere and warms the troposphere. AFAIK at most if not all wavelengths the stratosphere is optically thin in water's bands.
Thanks Andrew, I appreciate it.
Is one of the papers you referenced from NCAR (National Center for Atmospheric Research)? I have seen that being referenced in tweets claiming eruption is having a "warming effect".
FYI - I did investigate the authors of the references and found these authors from the third article (https://www.nature.com/articles/s43247-022-00580-w) include researchers from the National Center for Atmospheric Research, Boulder, USA
Charles G. Bardeen
Simone Tilmes
Michael J. Mills
Xinyue Wang
Douglas Kinnison
Anne S Glanville
Dr Dessler, I would like to thank you for the climate brink. It has been so much fun reading your posts. The first one I read was the carbon capture one and I’ve been hooked ever since.
Thanks!
Here's a relevant question: To what extent does atmospheric SO2, from volcanoes or fossil fuel combustion, react with OH to an extent that the oxidative capacity of the atmosphere is reduced? I have seen at least one paleoclimate paper that suggests that increased volcanic SO2 in the past reduced atmospheric OH, increased the lifetime of atmospheric methane, and forced greater warming.
That’s an interesting question and I don’t know the answer to it.
Could HT affected the colder earlier, heavier than average snowfall, late cold spring we had in Alaska last winter?
"local and regional environments"
You can't see the woods for the trees. There is one Sun, one planet, one atmosphere, one ocean and one climate system - chaotic and complex as it is.
Climate science is putting the jigsaw pieces together. Some pieces are missing but the picture and story it tells are clear. Certainly to - for all intents and purposes - all climate scientists, the global community of scientists and world governments.
DISCLAIMER: I believe science gives us our best view of reality and science ultimately depends on the judgement of experts. For example, Andrew Dessler and Zeke Hausfather.