That's some fun conflation right there! The ice age ended over 11,500 years ago... this sponge is 300 years ago. The study focuses on industrialization's impact on the climate.
Not sure that really refutes the point, since the temperature was down by about 0.25 degrees during that little ice age, according to the graph at the top of your link. after that little blip down it absolutely shot up. Little Ice Age barely had an affect on that graph, relatively
Aside from the correlation of the sponges' state changes and industrialization being in the same general time period, is there a causal link in the study?
This is the part I struggle with when I think of the massive temperature and sea level changes on a geologic time scale. The numbers that the current climate concern are dealing with (temp, sea level rise, etc.) are so tiny. How are the models controlled from the variables in the otherwise seemingly chaotic, wild swings in the lifetime of the planet? It's amazing to me that we can zoom in and make such high resolution determinations like that. I wish, as a laymen, someone could explain how we do it.
Given that every other warm interglacial period since the Pliocene ended in a slow slide into another ice age, a steady warming trend is indeed remarkable. There have been some 18 ~100,000 year ice age cycles since the Pliocene, and each glacial maximum ended about 3X as rapidly as it formed, so the world should be slowly cooling at present - but thanks to Homo ignis burning all the fuel, that trend has been reversed.
If you like, you could argue that human industry has saved the planet from another ice age anytime soon, but the job is certainly done at this point so we should stop burning fossil fuels now and try to stabilize the atmosphere at a constant steady state composition.
So we have already surpassed 1.5C by this measure, and will pass 2C earlier than predicted. Does that mean the various events predicted to occur around 2C will also occur earlier? Or not, because this paper measures from an early date?
The impacts of climate change are nonlinear. For example 100 year storms become 10 year storms, weather anomalies like polar vortices become much more common, and in general climactic extremes become both more extreme and more common. More concerningly, tipping points are reached (in order to rebuild the polar ice caps we won't need to go back -1.5C, but -4C), and tipping point events cause cascades that lock in climate change.
Worse yet, we're exiting the stable climactic conditions that civilization assumes is present. Assumptions regarding maximum temperatures, precipitation, ground water are baked into our reservoirs, power transmission lines, asphalt roads, train tracks, et cetera. Increased extreme weather compromises our ability to maintain society; look no further than the heat domes in the Pacific Northwest or the cold snaps in Texas to see how those assumptions compromise basic societal functions.
0.5C doesn't imply slightly worse weather, it means the additions of staggering amounts of heat to our land, water, and seas -- and the resulting amplifications of storms.
Parent might have been referring to the Little Ice Age [2], which according to the IPCC was
> ...a multi-centennial period of relatively low temperature beginning around the 15th century, with GMST averaging –0.03 [–0.30 to 0.06] °C between 1450 and 1850 relative to 1850–1900.
GMST = global mean surface temperature
Hardly, counts as valid given that we are talking about 1.5C/0.03 = 50x bigger change right now.
Earth is currently in the ice age called Quaternary glaciation.
It’s remarkable how reliably little there is to learn in climate threads here[2], so let me do my small part to present some basic scientific information that might be interesting to the curious.
Ice ages occur when the various Milankovitch cycles[1] and the locations of the Earth’s various tectonic plates line up just so. There needs to be a large polar continent on which large ice sheets can form to create a positive feedback loop where the ice increases the Earth’s albedo resulting in further cooling, and even more ice, &c. There also need to be at least two oceans to slow heat transfer. So even with a polar supercontinent there’s no ice age.
As you can see, currently all the conditions necessary for an ice age obtain, which is why geologists say we’re in one. Currently a glaciation is theoretically possible, but we don’t really know what gets that particular snowball rolling.
[2] Note the complete lack of Shannon entropy in the first child. Followed by dismissing scientific knowledge about the Earth’s climate as “moot” no less!
As long as there is any large amounts of ice on the planet, it will be called an ice age by geologists. So yes, we are in an ice age by that pedantic technical definition.
What's relevant in this discussion, is when was the last time temperature and climate were significantly lower on the Earth, coupled with much larger amounts of ice on the planet. This was over 10k years ago.
Of course, this whole discussion is moot, because natural causes have never in scientifically measurably history, caused GMST to change at the rate it is now - about 2C in 150 years, caused by humans dumping CO2 into the atmosphere.
That is such a pedantic discussion. Soon, we will be requiring multi-year studies to confirm that, because there is ice on the freezers that still run after the rolling blackouts, we are still on an ice age.
Meanwhile, emitting another 37GT of carbon to the atmosphere is preapproved.
> Why is warming 1.5C from a prior date not as bad as warming 1.5C from the more referenced date?
For the same reason that -2°C + 1.5°C is below freezing and -1°C + 1.5°C isn't.
> We were in an ice age 300 years ago.
No, we weren't. Not unless you're using the term in a way that includes the Late Cenozoic Ice Age that began 34 million years ago and which is ongoing. Mostly people use the term to refer to glacial periods, the last of which ended between 19000 and 12000 years ago — that's not the date being vague, it's how long it took — when the area now called Boston lost its roughly one mile deep ice sheet.
That was a 4.3°C temperature difference.
What did happen from roughly the 16th to the 19th centuries that's sometimes called the "Little Ice Age" only affected the North Atlantic region; locally by about 1°C, but even given the size of the North Atlantic, the global difference was less than 0.16-0.25°C, small enough that year-to-year differences exceeded this.
One problem is the speed of change, check https://xkcd.com/1732/ to have an idea. Adaptation needs time, else you get extinction. Very fast changes on global average temperature are correlated with big extinction events. And we depend on the ecosystem to be more or less as it is, for example to keep having agriculture.
Besides that, temperature just doesn't rise without affecting everything else. There are multiple (positive) feedback loops that increase the rate of warming directly (like ice melting reflecting less sunlight) or indirectly (i.e. permafrost thawing do their own carbon emissions) that get triggered once we get past some limits. Once the ball gets rolling things will get much faster, even without our intervention.
> Why is warming 1.5C from a prior date not as bad as warming 1.5C from the more referenced date?
You've probably put on a couple hundred pounds of weight over your lifetime. Do you think it would be negligible to put on another couple hundred pounds?
It's not so simple. 1.5C was decided on after assuming 2C would be fine after (warranted) political pressure from more at risk countries.
What are the risks is really more about climate sensitivity than a specific temperature, think of it as how much can change given a warming of X degrees. Recently there is growing scientific evidence that dangers we thought were only possible at high temp scenarios, say 3-4C, are possible at 2C or might even be underway. Meaning that the climate is more sensitive than had been projected. This means that not only according to the study linked above are we closer 1.5C + 2C, but we also have more to fear from passing those temps because more can go wrong at lower levels of warming.
Every tenth of a degree matters and we should stop obsessing over 1.5C or 2C and work on mitigating as much as possible and preparing for whats coming and slow emissions and pollution as much as possible
Montreal is particularly warm but dry this winter -- actually in many days warmer than Shanghai, China. I hope we don't have a super cold March this year.
I know that the comment is sarcastic but just in case, this will have the opposite effect, yes nuclear bombs will produce a lot of heat but that is for short amount of time and fires it will produce will last for sometime. But on the long time scale (months to years) the particles will precipitate in the sky and trapped and will cover most of the planet by radiation clouds which will prevent most of the sun photons from reaching the earth. So goodbye for planets and it will be the worst winter in earth's lifetime.
Then you say small? But how can we have small nuclear war? The effects of any nuclear exchange will be seen throughout the world (not in geopolitical sense).
I don't believe any of this is true—it certainly smells a lot like Cold War propaganda from the 50s. I don't believe we currently have anywhere near the nukes produced to have this happen even if we tried to perfectly cover the surface of the earth with nuclear explosions. To block out the sun we'd need something more like the volcanic winter of 536, continually erupting.
Nuclear war is bad, but it's certainly not "end life on earth" bad, or even "end humanity" bad by itself, just "deeply fracture humanity and probably enter a new era of civilization" bad.
I don't buy this particular flavor of thermonuclear war scare tactics because the math doesn't add up. World's entire nuclear arsenal adds up to a couple of gigatons, while the Mt. Tambora eruption in the 19th century alone was estimated to release 30 gigatons equivalent of energy.
The havoc a nuclear war would wreak on civilization is already bad enough merely through destroying infrastructure.
The mere energy wasn't the fear; the fear was nuking cities in particular would create the kind of dust that would get stuck at high altitudes, and put it at those high altitudes.
I think this is… no longer a widely held fear. Though I don't know if that change is for good reasons or bad reasons.
>The Sterno-Etrussia excursion may have amplified the climate shift, which, in the first place, was the effect of a decline of solar activity. During excursions and inversions, the magnetic moment decreases, which leads to an increased intensity of cosmic rays penetrating the upper atmosphere. Global changes in the electromagnetic field of the earth result in sharp changes in the climate-determining factors in the atmosphere, such as temperatures, total pressure field, moisture circulation, intensity of air flows, and thunderstorm activity. In addition, significant changes in the ocean circulation patterns and temperature regimes of oceans will have taken place.
Global climate change during the 13,500-b.p. Gothenburg geomagnetic excursion
>ROBERTS and Olsen1 suggested that high latitude atmospheric ionisation has an important role in nucleating cirrus clouds. And Harrison and Prospero2 deduce that, if this is correct, severe drops of the Earth's magnetic field strength, such as are believed to accompany reversals, would lead to increased upper atmospheric cloudiness at all latitudes and correspondingly to major climatic events. There is likely to be warming at high latitudes but considerable cooling in the middle latitudes, in a way analogous to the aerosols3.
Are there connections between the Earth's magnetic field and climate?
>Understanding climate change is an active topic of research. Much of the observed increase in global surface temperature over the past 150 years occurred prior to the 1940s and after the 1980s. The main causes invoked are solar variability, changes in atmospheric greenhouse gas content or sulfur due to natural or anthropogenic action, or internal variability of the coupled ocean–atmosphere system. Magnetism has seldom been invoked, and evidence for connections between climate and magnetic field variations have received little attention. We review evidence for correlations which could suggest such (causal or non-causal) connections at various time scales (recent secular variation ∼ 10–100 yr, historical and archeomagnetic change ∼ 100–5000 yr, and excursions and reversals ∼ 103–106 yr), and attempt to suggest mechanisms. Evidence for correlations, which invoke Milankovic forcing in the core, either directly or through changes in ice distribution and moments of inertia of the Earth, is still tenuous. Correlation between decadal changes in amplitude of geomagnetic variations of external origin, solar irradiance and global temperature is stronger. It suggests that solar irradiance could have been a major forcing function of climate until the mid-1980s, when “anomalous” warming becomes apparent.
Book on the subject: The Hidden Link Between Earth’s Magnetic Field and Climate
Global warming is real, but I wish we paid more attention to biodiversity and set goals there instead of fixating on temperature. I understand why temperature is there. It is easy to measure and an easy number to campaign around, but biodiversity, to me, is the actual point and focusing on temperature, while a major factor, diminishes the many other issues attacking it.
We’re already doing piss poor responding to a simple number that’s super easy to measure and evaluate predictions against. Do you think a harder to measure more argumentative measure would make global warming easier to tackle?
It is a really hard problem to survive. The only somewhat successful, so far, long term strategy I know of is the one we see in nature, diversity. Healthy ecosystems are always diverse. Diversity helps absorb shocks and exploit nitches that enable growth. But here is the kicker, diversity is helpful in every system to keep it alive, including the diversity of arguments we use in educating people. By focusing on just one argument we are making a mistake. I'm not saying we throw out temp targets and discussing them, but we need more valid discussions to increase the diversity of the discussion so that it survives and thrives.
Agree. Climate change is just one of the ways (and a big one) that habitat is being destroyed. Ocean acidification, conversion of forests and fields to farmland, and fertilizer runoff are others.
If the message that "Climate change is happening, it will cause starvation, large scale displacement, and regional conflicts, and significant economic disruption" isn't enough to make people take notice, why would "Here is a list of creatures you have never seen in real life and might live on a different continent from you" would have any impact?
It won't, because many of today's children are already growing up used to the lack of biodiversity . If you're living in a large city, wildlife and insects are things you see on Netflix and in video games and sort of abstractly know are somewhere out there. Maybe.
Well, I think I understand your sentiment. You believe it's racket because it hasn't happened yet, so it's just FUD?
I guess it could be, but is it worth ignoring the risk if it isn't just some FUD?
This is second-hand anecdotal, but: there are already agricultural issues in Croatia, and the people aren't sure why. A good suspect is global warming, and assuming it is, it probably isn't an isolated case either
I know there's lots of politicking and bickering around global warming, but IMO this is something worth putting differences aside to get to the bottom of, and how much of an impact it might have on the planet (and by extension people)
Are you saying we never had drought in times before co2 concentration went up 0.01 pct points over the last 100 years?
The climate change cult language is a lot like that of medieval christian nutcases: “oh there is drought because you angered the God with your sinful behaviour. You must repent with fasting, abstinence and prayers. … oh you say you did all that and still have drought? Thats because you have not prayed hard enough, try again. Or its perhaps God’s will. Now pay your subscription to the church.”
They are not saying the earth has never had a drought before the Industrial Revolution.
Frankly it'd be a fool that would think that they did.
Since the Industrial Revolution CO2 concentrations have increased by 50%, by half as much as was there for some 10,000 years prior.
The physical, engineering reason why comparing CO2 amounts in the amosphere against all other gases in the atmosphere is incorrect is simple - Oxygen and Nitrogen do not insulate - they are not greenhouse gases and do not trap infrared radiation.
What is significant is the increase in the amount of insulating gases - this directly ties to the increases in trapped energy.
It's a common mistake made by those that don't understand the physics.
Yeah, even if richrichie were correct, they're correct for the wrong reasons
Rich, I might humbly recommend looking up "demand avoidance" as a psychological phenomenon. I have a bit of it myself, that I try to be mindful of. It's essentially a pathology of resistance just because something is requested or required. It's possible to have in a systemic sense, and seems like you're feeling resistant to a popular hegemonic thought on principle, then backfilling with attempts at reason
Pat, All i see is some kind of hidden affinity to religion among the sciency types amd some weird end of the world fantasy.
I am open to a good argument. I am yet to see one though.
Per the crazies we are to spend trillions that pushes 100s of millions into poverty by spiking energy costs (esp cost of reliable energy), which will affect most econ activity downstream. This will create more conflicts, mass migrations and deaths NOW.
I'm not evangelical about the laws of thermodynamics, phase spaces, heat equations, etc. These are just things that reliably work to model and predict the physical world we inhabit (subject to measurement and error bars).
There's nothing particularly spiritual or faith based about such dull repeatable workings.
From 304 ppm (1924) to 420 (2024) is 38% rise in concentration. [1]
> Are you saying we never had drought in times before co2 concentration went up
This is a strawman. Nobody claims that AGW is the only reason for climate change. Year to year, some of those things swamp the short term effect of AGW. But while those other things are deviating and returning to their normal, AGW keeps pushing the average global average temperature higher, cumulatively until it becomes a serious threat.
Your logic is like dismissing someone's worry about 30,000 people a year dying in car crashes by saying, "Oh, this car rash thing is like religion... people died before cars existed."
Finally, religion is a cultural thing backed up by old stories. Climate research has the data -- while deniers have done zero research and pretend to know better.
% change in itself means nothing esp at smaller scales.
CO2 stats dont look that grave when we look at past estimates AND when we look at the benefits we have had from a warming and greening planet.
I would say that the rising level of oceans must be pretty significant for a lot of people, because most people live near a coast. Building a wall to protect NYC or Tokyo from flooding would be quite noticeable and expensive. Flooding a city that fails to handle the rise of the oceans would be even more noticeable.
Biodiversity may eventually become higher with a warmer overall climate, as it has occurred in the past.
Seriously, we had ice ages. Temperatures go up and down.
I can't bring myself to care about 86 instead of 83 degrees F in the summer and 23 instead of 20 in the winter. It's like moving a few hundred miles south. People get by fine.
I mean, I'm worried about all the weird chemicals in my food. That seems kinda wacky. I'm worried about all the biodiversity disappearing. Extreme-weather-itis would be scary, if it's actually a thing. I'm worried about breathing more CO2, and especially about the same in water (ocean acidification). I'm worried about many of the other impacts on climate.
"Climate change" was a step forward in terminology from "global warming," but we need about five more steps before it's something people care about.
We also need to acknowledge how much we don't know. Most of our models from 20 years ago didn't play out, which was obvious if you read the papers instead of listening to Al Gore. Bad things happened, but not the ones we thought would happen. It's a chaotic system. It doesn't work predictably.
> I can't bring myself to care about 86 instead of 83 degrees F in the summer and 23 instead of 20 in the winter.
Respectfully, you've not understood the measure and the meaning of global average.
For most of the past 200K years, most of human 'advanced' existance there's been little change in the global mean and all the seasons have changed as per written history and your recollection.
Lifting the global mean introduces more energy to the climate cells about the globe, driving more extreme changes, intoducing greater storms, setting us up for even more change as water vapor and methane levels rise which themselves are greater insulators that trap more heat than CO2.
> driving more extreme changes, intoducing [sp] greater storms
Respectfully, the mean temperature is the wrong measure for that. You want to look at measures like variance / std. div. -- the second moment and not the first.
That's why I listed under "Extreme-weather-itis" under things I care about.
> setting us up for even more change as water vapor and methane levels rise which themselves are greater insulators that trap more heat than CO2
Respectfully, you don't know that. The phrase should be "setting ourselves up for something possibly very bad." Extrapolation works worse than interpolation, and it's a chaotic system.
Respectfully, the level of imprecision and propaganda here is a root cause of scepticism.
People can understand why we don't want to play Russian Roulette, especially when most of the barrels are loaded, each with a different munition. That's more honest and likely leads to the outcome you want.
> You want to look at measures like variance / std. div. -- the second moment and not the first.
Possible concrete impacts of climate are discussed in detail in IPCC reports [1, 2]. For instance,
> Climate change will make some current food production areas
unsuitable (high confidence). Current global crop and livestock
areas will increasingly become climatically unsuitable under a high-
emission scenario (high confidence) (e.g., 10% by 2050, over 30%
by 2100 under SSP-8.5 versus below 8% by 2100 under SSP1-2.6).
Increased, potentially concurrent climate extremes will periodically
increase simultaneous losses in major food-producing regions.
> Climate change will make some current food production areas unsuitable (high confidence). Current global crop and livestock areas will increasingly become climatically unsuitable under a high- emission scenario (high confidence) (e.g., 10% by 2050, over 30% by 2100 under SSP-8.5 versus below 8% by 2100 under SSP1-2.6). Increased, potentially concurrent climate extremes will periodically increase simultaneous losses in major food-producing regions.
I believe that's simply expanding on my list of things in the "care about" bucket in my original post.
Also, notice the first two words in your quote: "climate change." Not "global warming." Global warming doesn't show up there.
The fixation on degrees C is making everyone miss the forest from the trees.
> Respectfully, the level of imprecision and propaganda here is a root cause of scepticism.
There is great certainty in the knowledge that a train will derail given certain conditions.
There is immense imprecision and a fundemental inability to predict where the cut glass vase in the dining car will come to rest.
This is baked into the nonlinear dynamics at play and seen as a simplest example in the Dzhanibekov effect | Tennis Racket Theorem where the centre of mass trajectory arc of a simple body is predictable whereas the tumblings about that projected arc are chaotic and unpredictable.
Those that demand certainty wrt small details fail to understand the physics of the big picture.
>There is great certainty in the knowledge that a train will derail given certain conditions.
>
> There is immense imprecision and a fundemental inability to predict where the cut glass vase in the dining car will come to rest.
That's the root of the communications problem. What we know, to your analogy, is that a train wheel is incorrectly attached and will fall off at some point.
What predictions are stating -- in media communicated to the general public from (and not just trash journalism; popular science journals, figures like Al Gore) -- is where the vase will land, when we don't even know where the train will derail.
Climate change deniers cite failed prediction after failed prediction. They couldn't do that if the predictions had error bars.
People can handle uncertainty just fine. However, if you tell someone a train is crashing in 100 meters over and over, they'll start to ignore you after a kilometer or two of failed predictions. If it derails 5 kilometers out, it's the boy who cried wolf.
We are pretty close to complete certainty that Bad Stuff will happen, but we grossly overstate the certainty of which specific bad things will happen and when.
> Those that demand certainty wrt small details fail to understand the physics of the big picture.
All I'm demanding is that
* we say "climate change" instead of "global warming;"
* include error bars;
* talk about impacts in terms of something other than degrees temperature rise; and
* stop fixating on degrees C as the sole metric.
Seriously. Watch Tucker Carlson at some point on the topic, or any similar commentator. 90% of what they say is correct, which is part of the reason it works so well. It's based on people on the left exaggerating for impact, simplifying, or using imprecise language. Al Gore sat us back 20 years with "An Inconvenient Truth."
> Watch Tucker Carlson at some point on the topic, or any similar commentator. 90% of what they say is correct
What are your specific arguments for assuming that Tucker Carlson, previously Fox News commentator, who has no academic degree, has a better understanding of climate science and error bars than the IPCC?
Ice ages occurred over the span of thousands to tens of thousands of years. The current change is happening in the order of decades to centuries. Not only will plants and animals have a hard time adapting to change that rapid, it will cause huge amounts of misery.
Maybe where you live 83 vs 86 degrees doesn't matter, but there are hundreds of millions of people that are living on the edge already. Once a century droughts are becoming common. When people are fighting for their lives and the lives of their children, they will move anywhere where things are marginally better ... causing economic chaos, and even war. But that doesn't seem to affect you in your air conditioned house.
> Most of our models from 20 years ago didn't play out,
That is false. The IPCC reports of 20-25 years ago are wrong only in that they undershot the severity. All of them, for political reasons, knowingly under reported the severity. I agree, don't listen to Al Gore, listen to the climate scientists. BTW, why do you think the paper you are reading is any more informed about climate change than Al Gore?
> Ice ages occurred over the span of thousands to tens of thousands of years
See "Little Ice Age" and it's effects.
> Once a century droughts are becoming common
"Climate change" not "global warming." On the whole, global warming makes for more rain. You can see another post here about rising atmospheric humidity.
> I agree, don't listen to Al Gore, listen to the climate scientists. BTW, why do you think the paper you are reading is any more informed about climate change than Al Gore?
A key difference are things like error bars.
With /proper/ error bars (accounting for all possible sources of error), right-wing media would have a hard time playing back false predictions.
Both terms have been in use for at least 50 years. It is a complex topic so no matter which two word moniker you coin to represent it, you can always poke a hole in it.
The people who think "climate change" is a fig leaf to cover up the fact that the globe didn't warm monotonically are simply ignorant. The models have always shown that some places will get drier, some will get wetter, some places cooler.
One of the things deniers always cherry pick is when some study mentions higher snowfall or rainfall in some particular region of the world. Odd that they believe the scientist when when they thing the datum supports their claim, but then will dismiss the same person who wrote the paper they cited as being in the pocket of George Soros or someone when the researcher doesn't support their preferred conclusion.
„It's a chaotic system. It doesn't work predictably“ is exactly the thing that worries me most - because that means it could get way worse than predicted today!
Temperature increases will be much larger over land. The values are for global averages, and most heat capacity is in the ocean. Not only that but some places will warm far more than others. Yes, all the other stuff is bad too, including ocean acidification. But they're intimately connected, and the rate of temperature change might be one of the largest changes in habitats worldwide.
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[ 3.3 ms ] story [ 130 ms ] threadThis is the part I struggle with when I think of the massive temperature and sea level changes on a geologic time scale. The numbers that the current climate concern are dealing with (temp, sea level rise, etc.) are so tiny. How are the models controlled from the variables in the otherwise seemingly chaotic, wild swings in the lifetime of the planet? It's amazing to me that we can zoom in and make such high resolution determinations like that. I wish, as a laymen, someone could explain how we do it.
If you like, you could argue that human industry has saved the planet from another ice age anytime soon, but the job is certainly done at this point so we should stop burning fossil fuels now and try to stabilize the atmosphere at a constant steady state composition.
We were in an ice age 300 years ago.
The climate has changed a lot compared to an ice age. Is it really going to change even more in the next 0.5C?
Worse yet, we're exiting the stable climactic conditions that civilization assumes is present. Assumptions regarding maximum temperatures, precipitation, ground water are baked into our reservoirs, power transmission lines, asphalt roads, train tracks, et cetera. Increased extreme weather compromises our ability to maintain society; look no further than the heat domes in the Pacific Northwest or the cold snaps in Texas to see how those assumptions compromise basic societal functions.
0.5C doesn't imply slightly worse weather, it means the additions of staggering amounts of heat to our land, water, and seas -- and the resulting amplifications of storms.
Parent might have been referring to the Little Ice Age [2], which according to the IPCC was
> ...a multi-centennial period of relatively low temperature beginning around the 15th century, with GMST averaging –0.03 [–0.30 to 0.06] °C between 1450 and 1850 relative to 1850–1900.
GMST = global mean surface temperature
Hardly, counts as valid given that we are talking about 1.5C/0.03 = 50x bigger change right now.
[1] https://en.wikipedia.org/wiki/Ice_age
[2] https://en.wikipedia.org/wiki/Little_Ice_Age
Ice ages occur when the various Milankovitch cycles[1] and the locations of the Earth’s various tectonic plates line up just so. There needs to be a large polar continent on which large ice sheets can form to create a positive feedback loop where the ice increases the Earth’s albedo resulting in further cooling, and even more ice, &c. There also need to be at least two oceans to slow heat transfer. So even with a polar supercontinent there’s no ice age.
As you can see, currently all the conditions necessary for an ice age obtain, which is why geologists say we’re in one. Currently a glaciation is theoretically possible, but we don’t really know what gets that particular snowball rolling.
[1] https://en.m.wikipedia.org/wiki/Milankovitch_cycles
[2] Note the complete lack of Shannon entropy in the first child. Followed by dismissing scientific knowledge about the Earth’s climate as “moot” no less!
What's relevant in this discussion, is when was the last time temperature and climate were significantly lower on the Earth, coupled with much larger amounts of ice on the planet. This was over 10k years ago.
Of course, this whole discussion is moot, because natural causes have never in scientifically measurably history, caused GMST to change at the rate it is now - about 2C in 150 years, caused by humans dumping CO2 into the atmosphere.
Meanwhile, emitting another 37GT of carbon to the atmosphere is preapproved.
That is how inaction is enforced.
For the same reason that -2°C + 1.5°C is below freezing and -1°C + 1.5°C isn't.
> We were in an ice age 300 years ago.
No, we weren't. Not unless you're using the term in a way that includes the Late Cenozoic Ice Age that began 34 million years ago and which is ongoing. Mostly people use the term to refer to glacial periods, the last of which ended between 19000 and 12000 years ago — that's not the date being vague, it's how long it took — when the area now called Boston lost its roughly one mile deep ice sheet.
That was a 4.3°C temperature difference.
What did happen from roughly the 16th to the 19th centuries that's sometimes called the "Little Ice Age" only affected the North Atlantic region; locally by about 1°C, but even given the size of the North Atlantic, the global difference was less than 0.16-0.25°C, small enough that year-to-year differences exceeded this.
Besides that, temperature just doesn't rise without affecting everything else. There are multiple (positive) feedback loops that increase the rate of warming directly (like ice melting reflecting less sunlight) or indirectly (i.e. permafrost thawing do their own carbon emissions) that get triggered once we get past some limits. Once the ball gets rolling things will get much faster, even without our intervention.
You've probably put on a couple hundred pounds of weight over your lifetime. Do you think it would be negligible to put on another couple hundred pounds?
What are the risks is really more about climate sensitivity than a specific temperature, think of it as how much can change given a warming of X degrees. Recently there is growing scientific evidence that dangers we thought were only possible at high temp scenarios, say 3-4C, are possible at 2C or might even be underway. Meaning that the climate is more sensitive than had been projected. This means that not only according to the study linked above are we closer 1.5C + 2C, but we also have more to fear from passing those temps because more can go wrong at lower levels of warming.
Every tenth of a degree matters and we should stop obsessing over 1.5C or 2C and work on mitigating as much as possible and preparing for whats coming and slow emissions and pollution as much as possible
Then you say small? But how can we have small nuclear war? The effects of any nuclear exchange will be seen throughout the world (not in geopolitical sense).
Nuclear war is bad, but it's certainly not "end life on earth" bad, or even "end humanity" bad by itself, just "deeply fracture humanity and probably enter a new era of civilization" bad.
https://globalnews.ca/news/2934513/empty-skies-after-911-set...
https://www.forbes.com/sites/arielcohen/2021/01/11/bill-gate...
I'm sure he won't be a Mr. Burns trying to sell more power when reducing the effect of solar panels.
The havoc a nuclear war would wreak on civilization is already bad enough merely through destroying infrastructure.
I think this is… no longer a widely held fear. Though I don't know if that change is for good reasons or bad reasons.
https://revistapesquisa.fapesp.br/wp-content/uploads/2019/07...
The ‘Sterno-Etrussia’ Geomagnetic Excursion Around 2700 BP and Changes of Solar Activity, Cosmic Ray Intensity, and Climate
https://www.cambridge.org/core/journals/radiocarbon/article/...
>The Sterno-Etrussia excursion may have amplified the climate shift, which, in the first place, was the effect of a decline of solar activity. During excursions and inversions, the magnetic moment decreases, which leads to an increased intensity of cosmic rays penetrating the upper atmosphere. Global changes in the electromagnetic field of the earth result in sharp changes in the climate-determining factors in the atmosphere, such as temperatures, total pressure field, moisture circulation, intensity of air flows, and thunderstorm activity. In addition, significant changes in the ocean circulation patterns and temperature regimes of oceans will have taken place.
Global climate change during the 13,500-b.p. Gothenburg geomagnetic excursion
https://www.nature.com/articles/265430a0
>ROBERTS and Olsen1 suggested that high latitude atmospheric ionisation has an important role in nucleating cirrus clouds. And Harrison and Prospero2 deduce that, if this is correct, severe drops of the Earth's magnetic field strength, such as are believed to accompany reversals, would lead to increased upper atmospheric cloudiness at all latitudes and correspondingly to major climatic events. There is likely to be warming at high latitudes but considerable cooling in the middle latitudes, in a way analogous to the aerosols3.
Are there connections between the Earth's magnetic field and climate?
https://www.sciencedirect.com/science/article/abs/pii/S00128...
>Understanding climate change is an active topic of research. Much of the observed increase in global surface temperature over the past 150 years occurred prior to the 1940s and after the 1980s. The main causes invoked are solar variability, changes in atmospheric greenhouse gas content or sulfur due to natural or anthropogenic action, or internal variability of the coupled ocean–atmosphere system. Magnetism has seldom been invoked, and evidence for connections between climate and magnetic field variations have received little attention. We review evidence for correlations which could suggest such (causal or non-causal) connections at various time scales (recent secular variation ∼ 10–100 yr, historical and archeomagnetic change ∼ 100–5000 yr, and excursions and reversals ∼ 103–106 yr), and attempt to suggest mechanisms. Evidence for correlations, which invoke Milankovic forcing in the core, either directly or through changes in ice distribution and moments of inertia of the Earth, is still tenuous. Correlation between decadal changes in amplitude of geomagnetic variations of external origin, solar irradiance and global temperature is stronger. It suggests that solar irradiance could have been a major forcing function of climate until the mid-1980s, when “anomalous” warming becomes apparent.
Book on the subject: The Hidden Link Between Earth’s Magnetic Field and Climate
https://books.google.fr/books?hl=fr&lr=&a...
I guess it could be, but is it worth ignoring the risk if it isn't just some FUD?
This is second-hand anecdotal, but: there are already agricultural issues in Croatia, and the people aren't sure why. A good suspect is global warming, and assuming it is, it probably isn't an isolated case either
I know there's lots of politicking and bickering around global warming, but IMO this is something worth putting differences aside to get to the bottom of, and how much of an impact it might have on the planet (and by extension people)
The climate change cult language is a lot like that of medieval christian nutcases: “oh there is drought because you angered the God with your sinful behaviour. You must repent with fasting, abstinence and prayers. … oh you say you did all that and still have drought? Thats because you have not prayed hard enough, try again. Or its perhaps God’s will. Now pay your subscription to the church.”
Frankly it'd be a fool that would think that they did.
Since the Industrial Revolution CO2 concentrations have increased by 50%, by half as much as was there for some 10,000 years prior.
The physical, engineering reason why comparing CO2 amounts in the amosphere against all other gases in the atmosphere is incorrect is simple - Oxygen and Nitrogen do not insulate - they are not greenhouse gases and do not trap infrared radiation.
What is significant is the increase in the amount of insulating gases - this directly ties to the increases in trapped energy.
It's a common mistake made by those that don't understand the physics.
That's essentially irrelevant to the current dynamics, just as the earth once being molten doesn't negate the cause|effect of recent human activity.
I feel almost certain that you're brighter than your comments here so far.
Rich, I might humbly recommend looking up "demand avoidance" as a psychological phenomenon. I have a bit of it myself, that I try to be mindful of. It's essentially a pathology of resistance just because something is requested or required. It's possible to have in a systemic sense, and seems like you're feeling resistant to a popular hegemonic thought on principle, then backfilling with attempts at reason
I am open to a good argument. I am yet to see one though.
Per the crazies we are to spend trillions that pushes 100s of millions into poverty by spiking energy costs (esp cost of reliable energy), which will affect most econ activity downstream. This will create more conflicts, mass migrations and deaths NOW.
I see you are strongly passionate about your beliefs.
There's nothing particularly spiritual or faith based about such dull repeatable workings.
> Are you saying we never had drought in times before co2 concentration went up
This is a strawman. Nobody claims that AGW is the only reason for climate change. Year to year, some of those things swamp the short term effect of AGW. But while those other things are deviating and returning to their normal, AGW keeps pushing the average global average temperature higher, cumulatively until it becomes a serious threat.
Your logic is like dismissing someone's worry about 30,000 people a year dying in car crashes by saying, "Oh, this car rash thing is like religion... people died before cars existed."
Finally, religion is a cultural thing backed up by old stories. Climate research has the data -- while deniers have done zero research and pretend to know better.
[1] https://www.co2levels.org/
Biodiversity may eventually become higher with a warmer overall climate, as it has occurred in the past.
Seriously, we had ice ages. Temperatures go up and down.
I can't bring myself to care about 86 instead of 83 degrees F in the summer and 23 instead of 20 in the winter. It's like moving a few hundred miles south. People get by fine.
I mean, I'm worried about all the weird chemicals in my food. That seems kinda wacky. I'm worried about all the biodiversity disappearing. Extreme-weather-itis would be scary, if it's actually a thing. I'm worried about breathing more CO2, and especially about the same in water (ocean acidification). I'm worried about many of the other impacts on climate.
"Climate change" was a step forward in terminology from "global warming," but we need about five more steps before it's something people care about.
We also need to acknowledge how much we don't know. Most of our models from 20 years ago didn't play out, which was obvious if you read the papers instead of listening to Al Gore. Bad things happened, but not the ones we thought would happen. It's a chaotic system. It doesn't work predictably.
Respectfully, you've not understood the measure and the meaning of global average.
For most of the past 200K years, most of human 'advanced' existance there's been little change in the global mean and all the seasons have changed as per written history and your recollection.
Lifting the global mean introduces more energy to the climate cells about the globe, driving more extreme changes, intoducing greater storms, setting us up for even more change as water vapor and methane levels rise which themselves are greater insulators that trap more heat than CO2.
Respectfully, the mean temperature is the wrong measure for that. You want to look at measures like variance / std. div. -- the second moment and not the first.
That's why I listed under "Extreme-weather-itis" under things I care about.
> setting us up for even more change as water vapor and methane levels rise which themselves are greater insulators that trap more heat than CO2
Respectfully, you don't know that. The phrase should be "setting ourselves up for something possibly very bad." Extrapolation works worse than interpolation, and it's a chaotic system.
Respectfully, the level of imprecision and propaganda here is a root cause of scepticism.
People can understand why we don't want to play Russian Roulette, especially when most of the barrels are loaded, each with a different munition. That's more honest and likely leads to the outcome you want.
Possible concrete impacts of climate are discussed in detail in IPCC reports [1, 2]. For instance,
> Climate change will make some current food production areas unsuitable (high confidence). Current global crop and livestock areas will increasingly become climatically unsuitable under a high- emission scenario (high confidence) (e.g., 10% by 2050, over 30% by 2100 under SSP-8.5 versus below 8% by 2100 under SSP1-2.6). Increased, potentially concurrent climate extremes will periodically increase simultaneous losses in major food-producing regions.
[1] https://www.ipcc.ch/report/sixth-assessment-report-cycle/
[2] Climate Change 2022: Impacts, Adaptation and Vulnerability https://www.ipcc.ch/report/ar6/wg2/
I believe that's simply expanding on my list of things in the "care about" bucket in my original post.
Also, notice the first two words in your quote: "climate change." Not "global warming." Global warming doesn't show up there.
The fixation on degrees C is making everyone miss the forest from the trees.
That's what I mean by driving more extreme changes - more variations per unit time and greater variance in those variations.
I did a little math once, it backed a few decades in global exploration geophysics for energy and mineral exploration.
>> as water vapor and methane levels rise
> Respectfully, you don't know that.
I'll defer to NASA and many many others then: https://climate.nasa.gov/explore/ask-nasa-climate/3143/steam...
AGU: Global Changes in Water Vapor 1979–2020 (2022) https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/202...
> Respectfully, the level of imprecision and propaganda here is a root cause of scepticism.
There is great certainty in the knowledge that a train will derail given certain conditions.
There is immense imprecision and a fundemental inability to predict where the cut glass vase in the dining car will come to rest.
This is baked into the nonlinear dynamics at play and seen as a simplest example in the Dzhanibekov effect | Tennis Racket Theorem where the centre of mass trajectory arc of a simple body is predictable whereas the tumblings about that projected arc are chaotic and unpredictable.
Those that demand certainty wrt small details fail to understand the physics of the big picture.
That's the root of the communications problem. What we know, to your analogy, is that a train wheel is incorrectly attached and will fall off at some point.
What predictions are stating -- in media communicated to the general public from (and not just trash journalism; popular science journals, figures like Al Gore) -- is where the vase will land, when we don't even know where the train will derail.
Climate change deniers cite failed prediction after failed prediction. They couldn't do that if the predictions had error bars.
People can handle uncertainty just fine. However, if you tell someone a train is crashing in 100 meters over and over, they'll start to ignore you after a kilometer or two of failed predictions. If it derails 5 kilometers out, it's the boy who cried wolf.
We are pretty close to complete certainty that Bad Stuff will happen, but we grossly overstate the certainty of which specific bad things will happen and when.
> Those that demand certainty wrt small details fail to understand the physics of the big picture.
All I'm demanding is that
* we say "climate change" instead of "global warming;"
* include error bars;
* talk about impacts in terms of something other than degrees temperature rise; and
* stop fixating on degrees C as the sole metric.
Seriously. Watch Tucker Carlson at some point on the topic, or any similar commentator. 90% of what they say is correct, which is part of the reason it works so well. It's based on people on the left exaggerating for impact, simplifying, or using imprecise language. Al Gore sat us back 20 years with "An Inconvenient Truth."
What are your specific arguments for assuming that Tucker Carlson, previously Fox News commentator, who has no academic degree, has a better understanding of climate science and error bars than the IPCC?
Maybe where you live 83 vs 86 degrees doesn't matter, but there are hundreds of millions of people that are living on the edge already. Once a century droughts are becoming common. When people are fighting for their lives and the lives of their children, they will move anywhere where things are marginally better ... causing economic chaos, and even war. But that doesn't seem to affect you in your air conditioned house.
> Most of our models from 20 years ago didn't play out,
That is false. The IPCC reports of 20-25 years ago are wrong only in that they undershot the severity. All of them, for political reasons, knowingly under reported the severity. I agree, don't listen to Al Gore, listen to the climate scientists. BTW, why do you think the paper you are reading is any more informed about climate change than Al Gore?
See "Little Ice Age" and it's effects.
> Once a century droughts are becoming common
"Climate change" not "global warming." On the whole, global warming makes for more rain. You can see another post here about rising atmospheric humidity.
> I agree, don't listen to Al Gore, listen to the climate scientists. BTW, why do you think the paper you are reading is any more informed about climate change than Al Gore?
A key difference are things like error bars.
With /proper/ error bars (accounting for all possible sources of error), right-wing media would have a hard time playing back false predictions.
The people who think "climate change" is a fig leaf to cover up the fact that the globe didn't warm monotonically are simply ignorant. The models have always shown that some places will get drier, some will get wetter, some places cooler.
One of the things deniers always cherry pick is when some study mentions higher snowfall or rainfall in some particular region of the world. Odd that they believe the scientist when when they thing the datum supports their claim, but then will dismiss the same person who wrote the paper they cited as being in the pocket of George Soros or someone when the researcher doesn't support their preferred conclusion.
"'Climate change' was a step forward in terminology from 'global warming,' but we need about five more steps before it's something people care about."
Yes, words do matter, and "climate change" is a huge step forward from "global warming" in terms of convincing people and affecting change.