The first somewhat comprehensive reviews of the DOE critical review are now coming online.
[Read more…] about Critiques of the ‘Critical Review’Extras
Are direct water vapor emissions endangering anyone?
In the EPA EF reconsideration document there is a section on p62 where they attempt to make the argument that the CO2 endangerment finding would also apply to direct water vapor emissions to the atmosphere, which is (according to them) obviously absurd. But both claims are bogus.
[Read more…] about Are direct water vapor emissions endangering anyone?The Endangerment of the Endangerment Finding?
The EPA, along with the “Climate Working Group” (CWG) of usual suspects (plus Judith Curry and Ross McKitrick) at DOE, have just put out a document for public comment their attempt to rescind the 2009 Endangerment Finding for greenhouse gas emissions.
[Read more…] about The Endangerment of the Endangerment Finding?National Climate Assessment links
For some reason, it has become hard to locate the various National Climate Assessments (NCAs) that have been produced by the USGCRP over the decades (and it’s pretty hard to find the USGRCP as well…). However, the reports are still accessible if you know where to look. So for future reference, here are all the links (and we’ve downloaded the pdfs locally so that they will always be available here).
NCA1 (2000)
- Full report (via the internet archive) (via gov archive) (local pdf)
NCA2 (2009)
- Full report (via the internet archive) (via gov archive) (local pdf)
NCA3 (2014)
- Full Report (via the NOAA library) (local pdf)
- Climate Science Supplement (via the internet archive) (local pdf)
NCA4 (2017)
- Volume 1 Climate Science Special Report (via the NOAA library) (local pdf)
- Volume 2 Impacts, Risks, and Adaptation in the United States (via the NOAA Library) (local pdf)
NCA5 (2023)
- The NCA5 Atlas (via ESRI)
- Full report (via the NOAA Library) (local pdf)
NCA6
There is no ongoing NCA6 process, even though it is mandated by Congress to be completed over the next few years. We’ll let you know if that changes.
Melange à Trois
In honor of the revelation today, that Koonin, Christy and Spencer have been made Special Government Employees at the Dept. of Energy, we present a quick round up of our commentary on the caliber of their arguments we’ve posted here over the last decade or so.
TL;DR? The arguments are not very good.
[Read more…] about Melange à TroisClauser-ology: Cloudy with a chance of meatballs
John Clauser’s theory of climate explained.
Some of you will have heard of John Clauser because he was an awardee of the 2022 Nobel Prize in Physics for his role in the experimental verification of quantum entanglement. Some of you will have heard of him because the first thing that he did after winning the Nobel was join a climate denial organization and make some rather odd claims about climate science. And some of you will never have heard of him (in which case, feel free to skip this post!).
At no point in his long and, by all accounts, successful, career has he ever published a paper on climate[1]. He has not penned an article, nor even a blog post or a tweet on the topic, and so any scientific basis for his opinions (if any) has been opaque… until recently. In the last few months he has given two interviews in which he goes into to detail about what he describes as a ‘missing element’ in climate science and what he imagines the consequences are for climate change. The first interview was for the Epoch Times (a far right-wing newspaper and media organization affiliated with Falun Gong). The second was a podcast with the somewhat troubled Chris Smith, an Australian journalist. (The material is somewhat similar in each). And more comprehensively, it was repeated in a recent video lecture as well.
And what is this supposed ‘missing element’? Clouds.
[Read more…] about Clauser-ology: Cloudy with a chance of meatballs2022 updates to the temperature records
Another January, another annual data point.
As in years past, the annual rollout of the GISTEMP, NOAA, HadCRUT and Berkeley Earth analyses of the surface temperature record have brought forth many stories about the long term trends and specific events of 2022 – mostly focused on the impacts of the (ongoing) La Niña event and the litany of weather extremes (UK and elsewhere having record years, intense rainfall and flooding, Hurricane Ian, etc. etc.).
But there are a few things that don’t get covered much in the mainstream stories, and so we can dig into them a bit here.
What influence does ENSO really have?
It’s well known (among readers here, I assume), that ENSO influences the interannual variability of the climate system and the annual mean temperatures. El Niño events enhance global warming (as in 1998, 2010, 2016 etc.) and La Niña events (2011, 2018, 2021, 2022 etc.) impart a slight cooling.
Consequently, a line drawn from an El Niño year to a subsequent La Niña year will almost always show a cooling – a fact well known to the climate disinformers (though they are not so quick to show the uncertainties in such cherry picks!). For instance, the trends from 2016 to 2022 are -0.12±0.37ºC/dec but with such large uncertainties, the calculation is meaningless. Far more predictive are the long term trends which are consistently (now) above 0.2ºC/dec (and with much smaller uncertainties ±0.02ºC/dec for the last 40 years).
It’s worth exploring quantitatively what the impact is, and this is something I’ve been looking at for a while. It’s easy enough correlate the detrended annual anomalies with the ENSO index (maximum correlation is for the early spring values), and then use that regression to estimate the specific impact for any year, and to estimate an ENSO-corrected time series.
The surface temperature records are becoming more coherent
Back in 2013/2014, the differences between the surface indices (HadCRUT3, NOAA v3 and GISTEMP v3) contributed to the initial confusion related to the ‘pause’, which was seemingly evident in HadCRUT3, but not so much in the other records (see this discussion from 2015). Since then all of the series have adopted improved SST homogenization, and HadCRUT5 adopted a similar interpolation across the pole as was used in the GISTEMP products. From next month onwards, NOAA will move to v5.1 which will now incorporate Arctic buoy data (a great innovation) and also provide a spatially complete record. The consequence is that the surface instrument records will be far more coherent than they have ever been. Some differences remain pre-WW2 (lots of SST inhomogeneities to deal with) and in the 19th C (where data sparsity is a real challenge).
The structural uncertainty in satellite records is large
While the surface-based records are becoming more consistent, the various satellite records are as far apart as ever. The differences between the RSS and UAH TLT records are much larger than the spread in the surface records (indeed, they span those trends), making any claims of greater precision somewhat dubious. Similarly, the difference in the versions of the AIRS records (v6 vs. v7) of ground temperature anomalies produce quite distinct trends (in the case of AIRS v6, Nov 2022 was exceptionally cold, which was not seen in other records).
When will we reach 1.5ºC above the pre-industrial?
This was a very common question in the press interviews this week. It has a few distinct components – what is the ‘pre-industrial’ period that’s being referenced, what is the uncertainty in that baseline, and what are the differences in the long term records since then?
The latest IPCC report discusses this issue in some depth, but the basic notion is that since the impacts that are expected at 1.5ºC are derived in large part from the CMIP model simulations that have a nominal baseline of ~1850, ‘pre-industrial’ temperatures are usually assumed to be some kind of mid-19th Century average. This isn’t a universally accepted notion – Hawkins et al (2017) for instance, suggest we should use a baseline from the 18th Century – but it is one that easier to operationalise.
The baseline of 1880-1900 can be calculated for all the long temperature series, and with respect to that 2022 (or the last five years) is between 1.1 and 1.3ºC warmer (with Berkeley Earth showing the most warming). For the series that go back to 1850, the difference between 1850-1900 and 1880-1900 is 0.01 to 0.03ºC, so probably negligible for this purpose.
Linear trends since 1996 are robustly just over 0.2ºC/decade in all series, so that suggests between one and two decades are required to have the mean climate exceed 1.5ºC, that is around 2032 to 2042. The first specific year that breaches this threshold will come earlier and will likely be associated with a big El Niño. Assuming something like 2016 (a +0.11ºC effect), that implies you might see the excedence some 5 years earlier – say 2027 to 2037 (depending a little on the time-series you are following).
2023 is starting the year with a mild La Niña, which is being forecast to switch to neutral conditions by mid-year. Should we see signs of an El Niño developing towards the end of the year, that will heavily favor 2024 to be a new record, though not one that is likely to exceed 1.5ºC however you calculate it.
[Aside: In contrast to my reasoning here, the last decadal outlook from the the UK MetOffice/WMO suggested that 2024 has a 50-50 chance of exceeding 1.5ºC, some 5 or so years early than I’d suggest, and that an individual year might reach 1.7ºC above the PI in the next five years! I don’t know why this is different – it could be a larger variance associated with ENSO in their models, it could be a higher present day baseline (but I don’t think so), or a faster warming rate than the linear trend (which could relate to stronger forcings, or higher effective sensitivity). Any insight on this would be welcome!]
References
- E. Hawkins, P. Ortega, E. Suckling, A. Schurer, G. Hegerl, P. Jones, M. Joshi, T.J. Osborn, V. Masson-Delmotte, J. Mignot, P. Thorne, and G.J. van Oldenborgh, "Estimating Changes in Global Temperature since the Preindustrial Period", Bulletin of the American Meteorological Society, vol. 98, pp. 1841-1856, 2017. http://dx.doi.org/10.1175/BAMS-D-16-0007.1
Unforced Variations: May 2022
Sorry for delay posting this month, but we’ve been considering how (or if) to go forward with open threads and comments. Looking at the multitude of constructive comments on the “End of blog comments” thread, it’s clear that many people appreciate the possibility of comments here, but that too often it disappoints by devolving into tedious bickering. There were many theories for why! Without necessarily subscribing to any particular diagnosis (there are many that capture some elements of what happens), we have decided to continue with comments for the time being, but with a few modifications.
To encourage people to post less often, but more substantively, we will limit commenters to one comment a day (so make it count!). Additionally, we will try to enforce a ‘one comment, one point’ rule to avoid people just cramming ten comments into one. Moderation of insulting, abusive, or just tedious comments will continue. Think more ‘Letters to the Editor’ than graffiti on the bathroom wall. This will hopefully also allow for more engagement from the RC scientists.
Back in the day, one of the goals of setting up the ‘Forced Variations’ threads was to segregate the more contentious arguments around solutions into one place, but that seems to have run it’s course. Thus we are going to revert to a single open thread, with a slightly broader climate theme than previously. Comments on generic political arguments or other issues that are not directly tied to climate will still be excluded.
We will let this play out for a couple of months and then reevaluate. Let us know what you think.
So with no further ado, let this month’s open thread begin…
The end of blog comments?
Over the last decade, commenting has dramatically moved from specific web-sites to general social media platforms, radically changing how people interact with longer-form content (such as blogs, substacks, newspapers and journalism). No single site can compete with the breadth of audience and engagement that is found on Facebook, Twitter, Reddit etc. This has led to a very clear reduction in the quality of comments on more specialized sites (like RealClimate), as many of you have observed. This is not a problem that appears amenable to stricter moderation.
We are therefore leaning towards suspending comment and open threads on the blog. Feel free to comment on this decision below. If the discussion is good and substantive, it will weigh towards the continuation of the commenting facility. Contrariwise, if it is shallow and unnecessarily hostile, then it is likely to be the last comment thread on this blog. We would still post articles, but anticipate that commentary and criticism will be hosted elsewhere.
As a replacement, we are happy to explore ways to better link to relevant discussions on social media – suggestions for plugins/methods are welcome.
A Nobel pursuit
Last week, the Nobel physics prize was (half) awarded to Suki Manabe and Klaus Hasselmann for their work on climate prediction and the detection and attribution of climate change. This came as quite a surprise to the climate community – though it was welcomed warmly. We’ve discussed the early climate model predictions a lot (including some from Manabe and his colleagues), and we’ve discussed detection and attribution of climate change as well, though with less explicit discussion of Hasselmann’s contribution. Needless to say these are big topics which have had many inputs from many scientists over the years.
But RC has a more attuned audience to these topics than most, and so it might be fun to dive into the details of their early work to see what has stood the test of time and what has not, and how that differs (if it does) from their colleagues and rivals at the time.
[Read more…] about A Nobel pursuit