@BerkeleyEarth [1/11] BEST's figures imply MUCH LOWER climate sensitivity than IPCC claims.
You show, "About 2.3°C of warming per doubling of CO2 (ignoring the role of other greenhouse gases and forcings)."
But to deduce climate sensitivity (to CO2), you CANNOT ignore other GHGs.
[cont'd]
@BerkeleyEarth [2/11] Even if we assume that none of the warming is natural, if 30% of the warming is due to increases in minor GHGs like O3, CH4, N2O & CFCs, then "climate sensitivity" from a doubling of CO2, according to BEST's figures, is only 0.7 × 2.3 = 1.6°C.
[cont'd]
@BerkeleyEarth [3/11] That's a "practical estimate" of climate sensitivity, from surface station measurements. However, if the best satellite data were used, instead of BEST's surface temperatures, sensitivity would be almost 30% lower: woodfortrees.org/plot/best/from… sealevel.info/BEST_vs_UAH_20…
[cont'd]
@BerkeleyEarth [4/11] That makes climate sensitivity to a doubling of CO2 only 1.23°C.
Since that's based on real-world forcing (instead of the faster rise used for the TCR definition), the 1.6°C or 1.23°C per doubling is "between TCR & ECS" (probably about an average of TCR & ECS).
[cont'd]
@BerkeleyEarth [5/11] ECS is usually estimated at 1.25× to 1.6× TCR. So:
If 1.6°C is avg of TCR & ECS, it means TCR is 1.23 to 1.42°C, and ECS is 1.77 to 1.97°C.
If 1.23°C is avg of TCR & ECS, it means TCR is 0.95 to 1.09°C, and ECS is 1.37 to 1.51°C.
@BerkeleyEarth [6/11] That gives an overall TCR range of 0.95 to 1.42°C, and an overall ECS range of 1.37 to 1.97°C.
Those sensitivities are obviously FAR BELOW the assumptions baked into most CMIP6 models and IPCC reports, which means their warming projections are much too large.
[cont'd]
@BerkeleyEarth [7/11] You say, "About 1.1°C of warming has already occurred," and "if carbon dioxide concentrations keep rising at historical rates, global warming could more than triple this century."
That's wrong, for two reasons.
[cont'd]
@BerkeleyEarth [8/11] 1. It assumes WILDLY accelerated warming, from an approx linear continuation of forcing, for which there's no basis. Even BEST's 0.192°C/decade yields only 1.536°C of add'l warming by 2100. UAH6's 0.134°C/decade yields only 1.072°C by 2100. sealevel.info/co2.html?co2sc…
[cont'd]
@BerkeleyEarth [9/11] 2. It assumes an implausible continuation of exponentially increasing CO2 level growth (necessary for continuation of the linear trend in forcing). But resource constraints ensure the forcing trend will fall below linear long before 2100. researchgate.net/publication/30…
[cont'd]
@BerkeleyEarth [10/11] Also, negative feedbacks (mainly terrestrial "greening," and oceans) are removing CO2 from the air at an accelerating rate. sealevel.info/feedbacks#gree…
So (unfortunately!) it's unlikely that mankind's use of fossil fuels can ever drive CO2 level above 700 ppmv.
[cont'd]
@BerkeleyEarth [11/11] Since CO2 forcing trend log(level) is almost certain to fall below linear later this century, rate of temperature increase, which is already too slow to reach the temperatures you project, should slow BELOW even the current slow 0.134°C to 0.192°C/decade linear trend.
###
@BerkeleyEarth@BerkeleyEarth, do you not have have any comment on the fact that your data implies a much lower climate sensitivity to rising CO2 levels than the IPCC claims?
The temperature measurements imply TCR between 0.95 & 1.42°C, and ECS between 1.37 & 1.97°C. Will you at least acknowledge that your measurements imply climate sensitivity well below IPCC estimates? sealevel.info/twitter_Berkel…
1/15≫ Dr. Belch (why oh why isn't she a gastroenterologist?) seems not to recognize the significance of the story.
Climate activists predicted that if Earth's average temperature got to 1.5°C above the pre-industrial (late Little Ice Age) baseline it would be a disaster. But they did, and nothing bad happened.
The significance of that is that it means the climate activists were completely wrong.
2/15≫ In case you're wondering, the 4 known factors which caused 2023 to be so mild were:
1. A strong El Niño spike. And
2. IMO 2020 shipping regulations drastically reduced sulfate aerosol air pollution (The IMO says they resulted in "an estimated 46% decrease in ship-emitted aerosols," which equates to a sudden 10% decrease in total global SO2 emissions, which is a large improvement in a short time, with a significant warming effect). And
3. The unusual 2022 Hunga Tonga eruption, which humidified the stratosphere. And
4. Also a little bit of warming from the ongoing slow rise in atmospheric CO2 levels (though only about 25 ppmv/decade).
It's all good, though (unfortunately) #1 & #3 are temporary.
3/15≫
Q: And what was the result of all that warmth?
1/7. Contrary to Prof. Christopher Taylor's claim, global greening is not "maxed out." That outlier Baozhang Chen study he cited is even contradicted by the IPCC:
2/7. Here's a compilation of that thread (because Twitter/𝕏 keeps shadowbanning my tweetstorms):
@elonmusk, @lindayaX, @support, @premium PLEASE end 𝕏's SHADOWBANNING of replies — even replies to one's own tweets (tweetstorms). What good is a tweetstorm if you can't find the 2nd tweet while viewing the 1st?threadreaderapp.com/thread/1719382…
3/7. Xin Chen et al (2024) refutes that outlier Baozhang Chen et al (2022) study:
Chen, Xin et al (2024). The global greening continues despite increased drought stress since 2000. Global Ecology and Conservation, Volume 49, 2024, e02791, doi:10.1016/j.gecco.2023.e02791.sciencedirect.com/science/articl…
1/10. When climate activists like Prof. Christopher Taylor have the power to block publication and deny tenure to young professors with differing opinions, it corrupts academia and distorts science.
2/10. Scientific consensuses exist about many things, but we don't talk much about them, because we don't disagree about them. If there's a hot debate about the existence of a consensus, it means there's no consensus.
3/10. One of the dishonest tactics used by the parasitic climate industry to promote their products is to pretend there's a scientific consensus that the "climate crisis" is real. That's a plain lie.
1/7. The "nutrition scare" is marketing FUD. Increasing CO2 does not decrease crops' nutritional value, except under contrived circumstances.
I had an impromptu online debate about the nutrition scare with its most prominent promoter, mathematician Irakli_Loladze, in comments on that Quora answer. If you're not a Quora member you can't read it there, so I saved it here:
If you skim it, do not overlook the important fact that since elevated CO2 is especially beneficial for legumes (beans, peas, etc.), which are grown for their high protein content, the rising CO2 level helps mitigate protein shortages in poor countries.
@cosmicfirepeace @a1337sti 2/7. Rising CO2 levels do not increase fires, either. That's climate industry propaganda. Here's what the data show: sealevel.info/learnmore.html…
@cosmicfirepeace @a1337sti 3/7. Rising CO2 levels do not increase droughts, either. That's also climate industry propaganda. Here's what the data show:
1/4. Joe P. wrote, "Averages are meaningless for determining heat"
You mean "confusing" (to you), not "meaningless."
Set your non-Panasonic microwave oven to half-power. It alternates between full power and zero power with a 50% duty cycle. That heats your coffee just as fast as a half-power microwave oven.
2/4. Joe P. wrote, "160w/m2 bb T is -40C, much too low"
You forgot to add roughly 342 W/m² of downwelling LW IR which originates from GHGs in the atmosphere: sealevel.info/NCA4_global_en…
3/4. Joe P. wrote, "It's derived after reducing TSI / 4 unnecessarily"
It accounts for the fact that the average irradiance over a sphere is 1/4th of the peak irradiance at the point where the surface of the sphere is perpendicular to the light source. It is not "unnecessary."