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One of the largest water districts in the country, The Metropolitan Water District of Southern California did not get the memo. They voted on September 12, 2023 to use RCP8.5 in their planning. Here is the link to the video where this was discussed and voted on. https://mwdh2o.granicus.com/player/clip/10485?view_id=12&redirect=true&h=7bd3fdeb3d8048682030fa736f6068d3

I would be interested in your thoughts if you have time to review the video.

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What is the time stamp? Thanks!

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18:29. Also, you can click on the agenda item with RCP8.5 in the text and it will go directly to that Item.

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I just watched. Wow, that is incredible. And ridiculous. A very good example of climate misinformation in the real world.

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From the UN Environment Program report -- "This year’s report tells us that unconditional NDCs point to a 2.6°C increase in temperatures by 2100, far beyond the goals of the Paris Agreement. Existing policies point to a 2.8°C increase, highlighting a gap between national commitments and the efforts to enact those commitments. In the best-case scenario, full implementation of conditional NDCs, plus additional net zero commitments, point to a 1.8°C rise. However, this scenario is currently not credible.

To get on track to limiting global warming to 1.5°C, we would need to cut 45 per cent off current greenhouse gas emissions by 2030. For 2°C, we would need to cut 30 per cent. A stepwise approach is no longer an option."

30 percent by 2030 does seem like a significant policy challenge...

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Dr. Pielke - this topic is very important and we need to spread the word as far and wide as we can. CA is doing their next climate report using effectively RCP 8.5, RCP 7.0 and RCP 4.5 emission scenarios from AR6 models. Do you have some Powerpoint slides that we can use to discuss with policy makers to show them the fallacy of the approach of using those emission scenarios? Awhile back you provided a short slide deck that was nice. You can place your name and THB trademark in them to assure you are credited as is proper. Thanks

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Yes, happy to help as would be ueful ... rpielkejr at gmail

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before running scenarios shouldn't we make sure that historical and actual data are measured accurately and not corrupted? because the evidence around this issue starts to be relevant. then there is the issue of models being flawed and poor performers in terms of forecasting. running scenarios based on the potentially wrong starting point and with flawed model might be good for the press, not much for science.

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Yes, good data is always important. Agreed.

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According to your chart annotation RCP 4.5 puts as at 2 degrees C warming in 2100? And your text seems to imply this is without any further mitigation? That seems very optimistic/good news!

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RCP4.5 is more like 2.4C

The new DAPD is RCP4.5-like but centers on 2C +/-

Both assume some degree of further mitigation (e.g., continuing to pursue NDCs)

A no further mitigation scenario is the NFA in that figure, with a top end of about 2.7C

And yes, all of this is very good news -- I've been writing about this since before Substack:

https://www.forbes.com/sites/rogerpielke/2019/11/30/global-carbon-dioxide-emissions-are-on-the-brink-of-a-long-plateau/?sh=4ab64256338d

When generally accepted (and it has to be, reality is stubborn in that way) everything will change

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I’m not sure why it has to be accepted when by your own analysis we won’t get accurate signals about the actual degree of warming for decades to come - that’s a double edged sword in that it leaves an open field for apocalypticism!

Does pursuing NDCs mean hitting Paris agreement emissions targets under RCP 4.5? If so I wouldn’t describe it as “stopping climate policy today” as you imply in the piece.

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Ooops. I just saw in your tweet from earlier today that you had already answered my questions about CB analysis.

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👍👍

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Understood. But those policies should be evaluated without any consideration of climate impacts - is that right?

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The evidence suggest that even if we’d like to, the alternative scenarios are close enough that they won’t allow for meaningful differentiation if climate impacts over many decades, and longer for certain variables

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OK - got it. Can you identify a couple of other ways that have been used to do CBA specifically on comparing one type of mitigation vs. a more expensive type of mitigation vs no mitigation?

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Sure, we can look at different impacts of mitigation policies on a range of variables beyond climate impacts, such as

Jobs created

Air pollution effects

Energy security consequences

Electricity prices

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So therefore a cost/benefit analysis does not make sense?

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Not using climate models based on scenarios of “current policies” vs further mitigation

Of course there are many other methods for CBA

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But how do you get at climate benefits without models? Or at least modeled assumptions?

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Models (in general) will always be useful

But ESMs in particular are unable to resolve specific, regional/local climate impacts relevant to decision making when scenarios are close together (e.g., RCP4.5 vs 3.4 vs 2.6)

That is why a revolution is coming

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Am I understanding this correctly: we may not know if mitigation efforts will have any benefit until the end of the century?

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We already know one of the benefits:

Full employment until 2100 for the climate modellers.

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Yes, using climate models

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moving the goalposts?

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What is policy success? 4.5 or 2.6?

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Generally a 2.6 trajectory is viewed as policy success. However, the issue is confused because 4.5 scenarios have often been used to reflect "policy success" -- that is incorrect, if the goal is to hit a 2.0C target. In fact, the world is presently tracking below a 4.5 trajectory.

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Have you graphed out the impact on grant funding under different RCP scenarios?

From what I've learned, due to your writing on this subject, I'm worried there will be significant sea level increases because of the tears from the RCP 8.5 fundamentalists.

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I think all the scenarios are all nonsense. Two facts are never mentioned. First, no one has ever offered proof that doubling CO2 to 800ppm will cause more energy absorption. Second, NASA data shows that present levels of CO2 are fully adequate to absorb all the ir ration in the only effective range, 14-16 microns. This data has been in use for decades by the IR Astronomers who require very accrate data to find the narrow windows that are useful to them. This shows that the data is reliable. Available at NASA Technical Memorandum 103957, Appendix E.

I offer no opinion as to actual climate warming, just that we are chasing an untested wrong explanation .

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you may be interested by this article:

van Wijngaarden, W. A. and Happer, W. (2020) ‘Dependence of Earth’s Thermal Radiation on Five Most Abundant Greenhouse Gases’, pp. 1–38.

Available at: http://arxiv.org/abs/2006.03098.

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I have seen this reference, which is just an abstract. The paper costs $35. However, even the abstract contains this line " where there is negligible saturation of the absorption bands".

So this has no bearing in the present case, where the 14-16micron band is saturated. This is the same fatal flaw as the models.

However, I'll make you a deal. I'll buy the whole paper and see if the abstrct is correct, if you will spring free a few bucks and buy my little booklet on Kindle (Carbon Dioxide-Not Guilty) and then tell me why the NASA data is to be disregarded.

I must emphasis that I have no arguement about actual gloal warming, only wasting our time and money on the belief the CO2 is the cause.

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HiIt turned out to be free. So send me an email address and I will send a free pdf of my little booklet.

I have gone through this paper, looking for his assumptions, as I expect his mathis all fine.

Particularly his assumption that there is "negligible saturation of the absorption bands".

It turns out that they placed reliance on the Nimbus 4 satellite IR transmission curve. His reference Hanel and Conrath In Nature 228, 143 (1970). This is the trap that many many people have fallen into.

Nimbus program was a weather program, and Nimbus 4 was an attempt to help determine the earths energy balance. It shows no detail, as its measuring steps were far too broad, it seems perhaps 50 microns or more. They had to cover 1-1,000 microns. Even 50micron needed 20 seperate measurements.

This of course smeared over all the detail, leaving a nice smooth curve from 80% transmission to 50% transmission to 80%.

If you took this as gospel, it would mean that the 14-16micron band was only 50% saturated! It would also mean that there are no clear windows for the IR astronomers-which would surprise them.

Basically this source can not be used for specific wave lengths, nor was it meant to be.

1970 was before the 1991 Nasa data, which was unavailable until 2022.

But it has been in use by the IR astronomers for 20 years or so, with accurate results, so it should be considered the authoritative standard.

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My take is that the modelists and scenarists are now acknowledging that policies that aim at Net-Zero in 2050 will not succeed (Fig 1 a). The target of 1.5 ℃ is therefore illusory, despite being enshrined by too many legislators.

But will policymakers do a U-turn when they realize that the extravagant costs of urgent mitigation measures will have to be supplemented by similarly costly adaptation measures anyway? Probably not, because too many parties are salivating at the idea of these pharaonic expenditures.

And if adaptation must be achieved anyway, what should be the purpose of mitigation?

To me, the timeframe available (10-30-100-300 years) is paramount, with urgency being the worst choice.

Weaning us off fossil fuels makes sense, but only with better solutions than those on the table today (inefficient, intermittent, and diluted energy conversions). Furthermore, it makes no sense to destroy productive agriculture (e.g. the EU's "Farm to Fork") for the sake of the climate.

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