>So, exactly what is the source of skepticism?

We should define climate skepticism, to avoid indicting a strawman. I'd start with my definition, as someone with unorthodox views on climate that often place me at odds with progressives.

It may be easier to start with the elements we agree on. Is the climate changing? Yes, obviously, visibly, measurably. Do human activities, including burning of coal and hydrocarbons, likely have a causal, contributory impact? Absolutely. Is the adoption of cleaner sources of energy: solar, hydro, geothermal, wind, nuclear, as well as investment in transmission and storage upgrades, a good thing? Unquestionably. Is climate change causing a growth in a class of threat to human life and prosperity (e.g. heat deaths, coastal flooding, extreme weather events, etc.)? Of course.

As for the areas where I diverge from progressives: Do I expect any amount of reduction in human activity, including reduction of coal and hydrocarbon combustion, reduction of overall energy usage, reduction of living standards and growth targets, to make any difference in the magnitude of the coming climate change at all in the long run? No.

The earth has both heated and cooled by orders of magnitude more than worst-case projections before humans started burning hydrocarbons.

Earth's climate is changing, yes, but historically, over the last 500 million years, the global average temperature has been as low as ~11° C at times; as high as ~34°C at others. You're reading that correctly: strictly natural processes that predate humanity itself have repeatedly changed the global averge temperature by as much as ~23°C. Ice ages occurred with zero human impact, just as the Cretaceous Thermal Maximum and global atmospheric CO2 levels exceeding 1000ppm occurred with zero human impact.

If you were to measure the full range of earth's climate variation over the history of the earth, and attempt to assign and attribute causality to all sources of that climate variation, you'd find that both the presence of all of humanity and the sum impact of all of human activity is an insignificant footnote. If this duration were a football field, humanity itself would be the last centimeter of grass in the distance of that football field; the period in which we've been measuring the climate is a thin slice of a single blade of grass.

The potential and capacity of natural processes to raise global average temperatures by 23° C has always been present, and nothing we can do will eliminate that potential and capacity.

The focus of human climate concern, accordingly, should be preservation of human life and wealth through adaptation to a changing climate, not futile efforts to prevent change itself, or an irrational alarmism that seeks to instill a widespread sense of anxiety over a process that cannot (and never could be) stopped, and for which the sum of humanity is not responsible for.

Build AC in Seattle. Set up better floodgates in New York City. Winterize the grid in Texas. Fix building codes to make houses more safe from hurricanes in Florida, and develop better solutions to stop the destruction of homes from wildfires in Colorado.

And yeah, do invest in alternative sources and production of energy. Energy is good. Energy is prosperity - it's causally linked to GDP, it's a direct requirement for quality of life / comfort / happiness. We need renewable energy. We need dispatchable energy. We need zero-emissions energy. We need energy that works at night, when it's cloudy, when we run out of oil, and when the wind's not blowing. We need better storage, better transmission. More energy, more sources, and lower costs for all of humanity.

We can't stop the world from changing, and trying to is foolish; we should accept that it is changing whether we try to prevent that or not, and focus on protecting and improving quality of life for all of humanity in the face of this always-changing environment on this little blue dot instead.

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awjlogan 5 hours ago | parent | next [-]

Your car can go at 0 kph and 100 kph. It’s the rate of the change that kills you, not the speed.

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anonym29 4 hours ago | parent [-]

Poor analogy. 23° C global average temperature increase, even slowly, will end a lot of life if nothing is done to address impacts. The rate of change isn't what causes those deaths; for 23° C warming, the terminal metric is indeed itself what kills, not the rate of change getting there.

That said, another section I've largely left out above is that it's effectively impossible to coordinate global action to meaningfully reduce human emissions from current levels. Europe and the US have actually already had declining emissions levels for decades now. This isn't a philosophy problem that you can talk your way to a solution on, it's a human psychology and game theory problem.

Trying to voluntarily convince global south nations to not adopt carbon-positive energy sources that solve real problems in the third world, and instead telling them to exclusively adopt your preferred alternatives (which do come with tradeoffs, be them in cost, complexity, availability/reliability) to appease what people facing food scarcity due to a lack of refrigeration due to a lack of electricity would consider "first world concerns" is an exercise in futility, and has some thematic emotional rhymes with colonial pasts where wealthy westerners demanded sacrifice from the global poor for the comfort of the wealthy westerners. It's a very tone-deaf plea.

	▲	awjlogan 3 hours ago \| parent \| next [-]
		I was addressing your statement that Earth is always changing. Yes, of course it is, obviously at +/- 20°C little that we recognise now would survive, but the transition is a lot less painful for you and yours if it happens over millions of years rather than a few centuries. The one hope is that renewables and batteries continue to reduce in cost, and grids everywhere develop around that paradigm. Economically, it’s inevitable, but there’s a lot of (to be stranded) money, social, and political will against it.
	▲	no_wizard 4 hours ago \| parent \| prev [-]
		Voluntarily convince? Yes, I agree asking other nations to afford something on top of struggling to afford things is not easy. However, a global reparation fund would make a difference. Not entirely unheard of for richer nations to fund these things for poorer ones

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amanaplanacanal 3 hours ago | parent | prev | next [-]

You seem to be completely ignoring the biggest problem. How do you propose the rich countries in the temperature zones deal with the billion climate refugees fleeing the inhospitable tropical areas of the planet?

	▲	lostlogin 2 hours ago \| parent [-]
		> How do you propose the rich countries in the temperature zones deal with the billion climate refugees fleeing the inhospitable tropical areas of the planet? We have the answer to this on the front page of our news sites. We try to impose a population cap. We recruit gangs of unidentifiable thugs to beat, imprison and deport them and we have race riots.

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card_zero 5 hours ago | parent | prev | next [-]

You seem to be saying the temperature change is mainly natural? But the expected natural change in the present era is slow and downward, I think.

I mean you have two separate points here, one is "adapt" and the other is "nothing can be done", which itself can be picked apart into different specific things that can't be done, such as on the one hand getting everybody to behave themselves conscientiously with one mind, and on the other hand unilateral geoengineering.

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anonym29 5 hours ago | parent [-]

I am saying that earth's average temperature has raised by 23° C before with zero human impact, and it will raise by as much as 23° C again, even if you cut all human carbon emissions to zero overnight (itself an effective impossibility for other reasons).

The average global temperature raising by even 2°C has catastrophic and devastating impacts to humanity, to say nothing of it raising by 20°.

We can't stop or prevent global average temperatures from rising, even if we do cut emissions to zero.

What we can prevent is the widespread loss of life (human, plants, and animals) and prosperity. Preventing loss of life and prosperity is good, and it's an achievable goal, so we should pursue that goal.

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w4der 4 hours ago | parent | next [-]

You are leaving out the rate at which the temperature has fallen and risen in the past and how that compares with the rising seen in recent decades.

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4 hours ago | parent | prev | next [-]

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card_zero 4 hours ago | parent | prev [-]

There's two reasons why temperature increases can't be stopped (without actually sending the heat away somewhere, such as into space): the first one is lag in the system if we cut emissions to zero, and the second is natural change in maybe 300 million years. Why bother mentioning the second of those?

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anonym29 4 hours ago | parent [-]

This is a strawman. The natural change happens orders of magnitude faster than 300 million years.

Also, is there a way to move heat into space that doesn't require adding more heat into the atmosphere than is removed from the expulsion? Or do you just mean this as a hypothetical example?

	▲	card_zero 4 hours ago \| parent [-]
		Well yeah, I just took the time interlude since the carboniferous and projected it into the future. But what's the real answer to how soon it would naturally get troublesomely hot, when worked out properly, and why is it still not very soon at all? Heat into space: I was thinking of "PDRC": https://en.wikipedia.org/wiki/Passive_daytime_radiative_cool... > If only 1%–2% of the Earth’s surface were instead made to radiate at [~100 W/m2] rather than its current average value, the total heat fluxes into and away from the entire Earth would be balanced and warming would cease. Which is, you know, a nice fantasy and theoretically works. Like a solar shield, but terrestrial. Edit for those thinking that even 1% is an unfeasibly large area: yes. It's about 5 million km², which is about one-fifth of North America. Maybe scatter the panels around the ocean?

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convolvatron 2 hours ago | parent | prev | next [-]

there was no human impact for quite a bit of that variability over 500m years because just there were no humans, including the Cretaceous.

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pstuart 5 hours ago | parent | prev [-]

> And yeah, do invest in alternative sources and production of energy

This right here, it should be a Manhattan Project level of urgency, but at global "Hail Mary" level of cooperation and effort.

And the best part is that it's not like that investment is wasted -- it's foundational and will allow us to do incredible things with it.

Meanwhile the President of the United States is actively cancelling such work and doubling down on coal. Wheee!