May 8, 2023·edited May 8, 2023Liked by Andrew Dessler

Great analysis, thanks. Now I don't have to do it.

This is similar to setting 1880 as our "baseline" and saying there wasn't any noticeable warming until the late 70's. It works if the person you are talking to doesn't know that 1880 was the hottest year of the 19th century. By about 0.6C!

This was also the tactic with the "great slowdown" of warming between 2000 and 2010 that Deniers trumpeted as "proof" Global Warming was a hoax. It worked only if you set 97/98 as your starting point. Once again, El Nino years and the hottest years of the 20th century.

People never seem to learn that these kinds of arguments are structured to appeal to what they "want to believe". Not reality.

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What you're talking about here is slightly different — endpoint selection. That's obviously an issue (see https://skepticalscience.com/graphics.php?g=465). What Zeke is talking about is that, if you put a trend into a short and noisy data set, it can be very hard to pick out the trend.

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As I said, "similar". Both tactics rely on the desire of people to believe when someone is telling them what they what to hear. This is why con men can make a good living.

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I´m no Climatologist, so could someone please help me understand something. Your final graph shows an average climb in temperature by 0.2°C per Decade, to my ears that sounds miniscule. 1 degree in 50 years doesn´t strike me as an enormous problem.

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You're right, TheDaltonsDuo, a 1°C temperature change is miniscule, and benign.

We've probably already had at least that much warming since the late 1800s, and it's been beneficial, rather than harmful. (NCA4 estimates 1.14°C [1.02 to 1.27], though that confidence interval is, IMO, …overly confident.)

Thus far, there've been no significant harmful effects from either the large increase in atmospheric CO2, or the consequent slight warming trend:

Coastal sea-level rise acceleration is negligible. Hogarth reported, "Sea level acceleration from extended tide gauge data converges on 0.01 mm/yr²." An acceleration of 0.01 mm/yr², if it continued for 150 years, would add just 11.25 cm to global sea-level, which is obviously insignificant.

No category of storms has worsened. In fact, some destructive storms have decreased substantially, notably strong tornadoes. (Nobody knows for certain why that has happened, but I've heard it speculated that it's because Arctic Amplification has slightly reduced latitudinal temperature gradients.)

Droughts have not worsened. In fact, the global drought trend is slightly down. More importantly, higher CO2 levels substantially mitigate drought impacts, by making plants more water-efficient and drought-resilient, through improved CO2 stomatal conductance relative to transpiration. It is settled science, which has been extensively studied, and widely reported in the agronomy literature (though most climate scientists are apparently unfamiliar with it).

Scientists called temperatures like what we're currently enjoying a "climate optimum." In fact, even temperatures which were much warmer than now, like the Eemian Optimum, are called "optimums," because they're objectively better than cold periods.

Recent warming has been both slight and slow compared to past natural warming episodes, like the Younger Dryas, and two dozen previous natural Dansgaard-Oeschger warming events, which were ≈ 10× more rapid then recent warming, with no catastrophic consequences. (However, Antarctic ice cores show that the warming events were much more gradual in the southern hemisphere than the northern.). According to NOAA, the Younger Dryas termination is thought to have warmed Greenland by 10 °C in just one decade. (That's probably about twice the average warming rate in the northern hemisphere, and perhaps 3× the global rate, but that still makes global warming at the end of the Younger Dryas about an order of magnitude faster than recent warming.)

Thankfully, those very large, abrupt temperature changes apparently did not cause mass extinctions. Mankind, polar bears, pikas, coral, and nearly every other existing species of animal and plant all survived those sharp climate changes. That suggests we needn't fear that the current (comparatively slight) warming trend could be catastrophic for any of them.

What's more, one of the fortuitous things about "global warming" is that it isn't actually very "global." It disproportionately warms frigid winter nights at chilly high latitudes. The tropics are warmed less, which is nice, because they're warm enough already.

Arrhenius anticipated that, over a century ago. He wrote, "By the influence of the increasing percentage of carbonic acid [CO2] in the atmosphere, we may hope to enjoy ages with more equable and better climates, especially as regards the colder regions of the earth, ages when the earth will bring forth much more abundant crops than at present, for the benefit of rapidly propagating mankind."

He was right, though the greater benefit is through CO2 fertilization, and reduced drought impacts, thanks to CO2-induced improvements in plant water use efficiency. The effects on temperature are benign, but slight.

At temperate latitudes, 1°C equates to about the amount of climate change you get from a sixty mile change in latitude.

1°C is also about the climate change you get from a 500 foot change in altitude.

In the American Midwest, farmers can fully adjust for 1°C of warming by advancing planting dates by about six days.

1°C is less than the hysteresis ("dead zone" or "dead band") in a typical home thermostat. The indoor temperatures in your home probably fluctuate, up and down, by 2-3° F, all day long, and you probably don't even notice it. Such a tiny change is even less noticeable outdoors (unless it makes the difference between freezing and not freezing).

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That’s a good question! Think of the climate related problems (drought, flooding etc.) already caused or enhanced by the 1 deg C warming that we have already experienced. If you look at past warming periods related to natural causes, today’s anthropogenic warming is both incredibly rapid and signifies an enormous gain of energy in the planet. This has had and will continue to have increasing overall negative consequences to human well being, especially for already vulnerable groups of people around the world (food, housing, political and economic instability etc.).

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Indeed, and the global average obscures a lot of localized changes. The last ice age was probably around 5C colder globally than today, but was a very different planet. 2C global warming means 3C on average over land, and ~4C over high latitude regions.

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Jun 12, 2023·edited Jun 12, 2023

"If 1σ consumes a trend there is no trend." - Seth Cressey

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You would probably like my dissection of a 'Climate Disinformation Campaign'.

The Crisis Report - 37

Anthropogenic Particulate is a form of Geoengineering. We have been geoengineering the Earth's Climate for awhile.

The Crisis Report - 38

Anthropogenic Particulate is a form of Geoengineering. Dissecting a Climate Disinformation Campaign and Discussing Historical Geoengineering of the Climate. - Part Two.

The Crisis Report - 39

Anthropogenic Particulate is a form of Geoengineering. Dissecting a Climate Disinformation Campaign and Discussing Historical Geoengineering of the Climate. - Final

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