We are, but that is sort of the "trade name" for anthropocentric climate change. Which, if you read a lot of papers track the rising temperatures but have a variety of opinions of how exactly that will affect the climate. One such change can be triggering a sudden glaciation event.
A sort of Mpemba effect on a global scale? That's got to be the goofiest global warming thing I've heard yet, and I've been following the movement since 1992.
Not really, Mpemba is about water freezing. There was a recent Nature paper discussion which looked at the non-linear effects of various climate modifiers[1]. I pointed out that some models have warming causing the onset of a glaciation event, the mechanics are warmer air carries more water vapor (itself a powerful greenhouse influence) which sets up a positive feedback loop making the air warmer and then sucking up more water from evaporation, which retains more heat which makes the air warmer. You cross the dewpoint in the stratosphere and that gets 100% solid cloud cover above the tropsphere. At which point the albedo of the planet goes way up (its a uniform white reflector at that point) and the water in the troposphere precipitates out as the mother of all snow storms and the greenhouse gas equivalent of nuclear winter.
Do I actually think this is going to happen? Not really. Are we recording unprecedented levels of greenhouse gases? Yes. Is the climate we're experiencing similar to the climate that was in effect when those levels occurred in the past? Not really, the early Pleistocene was much warmer than it is now. Moore's paper from 1980 was probably pretty influential here. He, like others, is/was really interested in why we had ice ages in the first place.
The point though is that we talk about "global warming" which implies to a lot of people who don't read the papers that our inputs into the climate will only cause increased heat, but it is more accurate to say "climate change" since we don't have good non-linear models for how the planet responds to all the forcing functions we are throwing at it.
We casually throw around terms like "hottest temperatures ever recorded" or "lowest ice levels on record" but some times lose sight of the fact that the "record" we've been keeping in terms of climate change is, according to ice cores, and other geologic carbon dating of glaciation events, perhaps 2% of a cycle. (assuming 100kyr cycle and 2kr of nominal human recordings). Remember that 2% of a year is one week. We can't take a week's worth of measurements and even imagine all of the variations we'll see that year, so we have to be careful about extrapolating with the amount of data we have. Pretty much everyone (except some really hard liners) can agree that climate can and will change, its understanding that change which we can only develop as we go along. And the latest contribution to our understand was the Nature paper that said, in essence, don't try to model this stuff with linear models.
Thanks, that's interesting as well as refreshingly reasonable with respect to our limited knowledge. However, your summary seems at odds with the field of climate science's continuous and confident prescriptions for human life. If that is the extent of our knowledge, how can we tell any nation to accept lower growth and poorer health by curtailing fossil fuel use?
I would be interested in seeing "confident prescriptions for human life" in an actual paper. What I have seen, and when I've been present at Q&A sessions with scientists presenting their results, was a lot of discomfort and equivocating when someone would ask the question "If we do <x> will it mitigate or reverse the changes in climate?". I watched one poor guy not answer the question "If I had a magic wand and removed all anthropogenic CO2 from the air, would it stop global warming?" The questioner was clearly a climate skeptic but the truth is that science doesn't actually know. That was the root of the resistance to the iron fertilization experiments[1]
As a result we have a lot of research which clearly indicates that humans are destabilizing the climate which will induce it to change, but no one that I have found has been willing to stand up and claim they could drive the climate in a particular direction or speak definitively on what the eventual result of our destabilizing influences will have.
Our ability to predict outcomes is limited by our understanding of the complex interactions (which is why I like the recent Nature article, it really gets to that point) We can make fairly mechanical predictions of the form "If this much fresh water was dumped into the ocean, it would go up by this many meters." Some have also speculated that the increased weight on the mantle of all that water will cause a massive increase in volcanism as magma is compressed.
The most definitive statement I have ever read from an actual scientist is that by generating fewer green house gases we will destabilize it less. The elephant in the room then is without human participation the planet has seen warm spells and ice ages. So at best, our influence is eradicated and it goes back to what ever was previously changing the climate before we came along.
As a result I don't think telling anyone to accept lower growth and poorer health by curtailing fossil fuel use is a reasonable strategy. You can tell them that the more energy efficient they are, the better their economy will be able to support them. Telling them to suffer because it will stop climate change does them a disservice. Telling them to get off fossil fuel because they will be healthier and more prosperous if they can live on renewable sources benefits from being demonstrably true.
Comments
We are, but that is sort of the "trade name" for anthropocentric climate change. Which, if you read a lot of papers track the rising temperatures but have a variety of opinions of how exactly that will affect the climate. One such change can be triggering a sudden glaciation event.
A sort of Mpemba effect on a global scale? That's got to be the goofiest global warming thing I've heard yet, and I've been following the movement since 1992.
Not really, Mpemba is about water freezing. There was a recent Nature paper discussion which looked at the non-linear effects of various climate modifiers[1]. I pointed out that some models have warming causing the onset of a glaciation event, the mechanics are warmer air carries more water vapor (itself a powerful greenhouse influence) which sets up a positive feedback loop making the air warmer and then sucking up more water from evaporation, which retains more heat which makes the air warmer. You cross the dewpoint in the stratosphere and that gets 100% solid cloud cover above the tropsphere. At which point the albedo of the planet goes way up (its a uniform white reflector at that point) and the water in the troposphere precipitates out as the mother of all snow storms and the greenhouse gas equivalent of nuclear winter.
Do I actually think this is going to happen? Not really. Are we recording unprecedented levels of greenhouse gases? Yes. Is the climate we're experiencing similar to the climate that was in effect when those levels occurred in the past? Not really, the early Pleistocene was much warmer than it is now. Moore's paper from 1980 was probably pretty influential here. He, like others, is/was really interested in why we had ice ages in the first place.
The point though is that we talk about "global warming" which implies to a lot of people who don't read the papers that our inputs into the climate will only cause increased heat, but it is more accurate to say "climate change" since we don't have good non-linear models for how the planet responds to all the forcing functions we are throwing at it.
We casually throw around terms like "hottest temperatures ever recorded" or "lowest ice levels on record" but some times lose sight of the fact that the "record" we've been keeping in terms of climate change is, according to ice cores, and other geologic carbon dating of glaciation events, perhaps 2% of a cycle. (assuming 100kyr cycle and 2kr of nominal human recordings). Remember that 2% of a year is one week. We can't take a week's worth of measurements and even imagine all of the variations we'll see that year, so we have to be careful about extrapolating with the amount of data we have. Pretty much everyone (except some really hard liners) can agree that climate can and will change, its understanding that change which we can only develop as we go along. And the latest contribution to our understand was the Nature paper that said, in essence, don't try to model this stuff with linear models.
[1] http://www.nature.com/nclimate/journal/v5/n5/full/nclimate25...
[2] https://www.researchgate.net/profile/Ted_Moore/publication/2...
Thanks, that's interesting as well as refreshingly reasonable with respect to our limited knowledge. However, your summary seems at odds with the field of climate science's continuous and confident prescriptions for human life. If that is the extent of our knowledge, how can we tell any nation to accept lower growth and poorer health by curtailing fossil fuel use?
I would be interested in seeing "confident prescriptions for human life" in an actual paper. What I have seen, and when I've been present at Q&A sessions with scientists presenting their results, was a lot of discomfort and equivocating when someone would ask the question "If we do <x> will it mitigate or reverse the changes in climate?". I watched one poor guy not answer the question "If I had a magic wand and removed all anthropogenic CO2 from the air, would it stop global warming?" The questioner was clearly a climate skeptic but the truth is that science doesn't actually know. That was the root of the resistance to the iron fertilization experiments[1]
As a result we have a lot of research which clearly indicates that humans are destabilizing the climate which will induce it to change, but no one that I have found has been willing to stand up and claim they could drive the climate in a particular direction or speak definitively on what the eventual result of our destabilizing influences will have.
Our ability to predict outcomes is limited by our understanding of the complex interactions (which is why I like the recent Nature article, it really gets to that point) We can make fairly mechanical predictions of the form "If this much fresh water was dumped into the ocean, it would go up by this many meters." Some have also speculated that the increased weight on the mantle of all that water will cause a massive increase in volcanism as magma is compressed.
The most definitive statement I have ever read from an actual scientist is that by generating fewer green house gases we will destabilize it less. The elephant in the room then is without human participation the planet has seen warm spells and ice ages. So at best, our influence is eradicated and it goes back to what ever was previously changing the climate before we came along.
As a result I don't think telling anyone to accept lower growth and poorer health by curtailing fossil fuel use is a reasonable strategy. You can tell them that the more energy efficient they are, the better their economy will be able to support them. Telling them to suffer because it will stop climate change does them a disservice. Telling them to get off fossil fuel because they will be healthier and more prosperous if they can live on renewable sources benefits from being demonstrably true.
[1] http://www.nature.com/nature/journal/v457/n7229/abs/nature07...
I suppose I have been distracted by media reports, but certainly everything you've written here is reasonable.