19 Comments

You have to love the "language" of the IPCC, I do a lot of risk based work and one of the key things for me is the language I use to ensure clarity on what risk actually exists or is just a figment of peoples imagination. The phrase "virtually certain" is laughable and tells me they have nothing to back up what they claim. Because they are "almost" certain. but "not quite" because the polar bears are not invading backyard swimming pools to cool off.

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Checking for a friend that this thread is still open to comment.

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What is the IPCC definition of "agricultural and ecological drought"?

Can anyone allay, or confirm, my suspicion they're somewhat gerrymandered categories created to have something that is increasing.

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There is a very important, even critical point you miss in discussing attribution. Only forecasts are relevant. Being able to adjust their numbers on human contribution to the point that they can approximate current conditions doesn't actually establish any evidence of human influence. It merely means that they are claiming everything they can't explain is human influence. That is an extremely critical difference. Once the models come up with an accurate 10 year out prediction, then we can start discussing a human influence, the data to date shows nor real evidence of human influence, just lots of evidence of stuff they don't understand.

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Why was the period for the claim of "unprecedented warm days and nights" cut off at 1950? After all we have records for the 1930's and earlier. This begs a larger question: to what extent has the generic question of attribution for complex chaotic (on all scales, including time) non-linear systems where experimentation is not possible, been resolved? Is a 70 yr period really adequate for this type of work? I suspect not given climate is the average 30 yrs. I suspect that you really need 300 yrs to get to high certainty on attribution. On top of that, all of these things are regional in nature, so you need 300 yrs of regional data too.

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When you are attempting a juxtaposition of two data sets (past and present) you need to establish maximum confidence for both and moreover, make sure that the things you compare are about the same in terms of quality. I don’t see those premises accounted for in the IPCC’s methods.

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The bastards have slightly modified 11.7.3.2 by removing the transparent "observational trends in tornados, hail and lightning associated with severe convective storms are not robustly detected" with "Analysis of the environmental conditions favourable for severe convective events INDIRECTLY indicates the climatology and trends of severe convective event".

On the plus side, the next paragraph says "in the united states, it is indicated that there is no significant increase in convective storms, and hail and severe thunderstorms".

Thank you for what you do.

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Dear Roger Pielke, what you have wrote here is pure bullshit.

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In IPCC AR6, WGI, there seem to be conflicting statements concerning river floods. In Ch. 11, p. 11-8, we read:

"River floods are projected to become more frequent and intense in some AR6 regions (RAR, SEA, SAS, NWS) (high confidence) and less frequent and intense in others (WCE, EEU, MED) (high confidence)."

In Ch. 12, p. 12-68, we read:

"There is high confidence of an observed increasing trend of river floods in Central and Western Europe (WCE) and medium confidence of a decrease in northern (NEU) and Southern Europe (MED)."

WCE ("Western and Central Europe") encompasses the area of severe flooding in July 2021, and therefore scientific statements about climate change as the cause of the flood are especially important. Almost all politicians and ever-present lobby groups just before the election in Germany at 26th of September see the dominant cause of the damage in the emission of greenhouse gases.

There is also a "Rapid attribution of heavy rainfall events leading to the severe flooding in Western Europe during July 2021" by numerous authors of "world weather attribution":

https://www.worldweatherattribution.org/wp-content/uploads/Scientific-report-Western-Europe-floods-2021-attribution.pdf

This article is also used as evidence of a man-made climate catastrophe. And the headline of the press release of "world weather attribution" supports this opinion:

"Heavy rainfall which led to severe flooding in Western Europe made more likely by climate change":

https://www.worldweatherattribution.org/heavy-rainfall-which-led-to-severe-flooding-in-western-europe-made-more-likely-by-climate-change/

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Professor Pielke, I applaud your dispassionate and evidentiary approach to scientific “controversy.” I just watched your entire interview with Nick Gillespie and must say, you are an intellectual kindred spirit! I am not a climate scientist, but a scientifically trained psychiatrist, who shares your concern about politically motivated distortions of the actual empirical evidence supporting public policy. I look forward to reading more of your reasoned thoughts about your field. Thank you.

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