There is no doubt that attribution claims have run far out ahead of detection of trends
"Since 1951, the number of heavy rainfall days per year for the whole of Germany has hardly changed, almost independently of their definition" mdpi.com/2073-4441/12/7…
I'm not sure how the current strong attribution claims (it's obvious, right?) can be reconciled with the observational data, but I'm sure there is an explanation
If certain extreme events have become much more likely, then evidence should show them being more likely? Or not?
Here is what the US NCA 2017 said about "attribution without detection"
Decreases the chances that you'll miss identifying a climate signal in a rare event, but increases the chances of falsely identifying such a signal
It turns out -- and science scholars will love this -- the choice of methodology, and thus choice of result, depends upon the message one wishes to convey
"More meaningful questions" take us back to the good ol' IPCC detection and attribution framework
As I have argued often, if conventional IPCC detection & attribution work showed clearly increasing extremes & plausible causes, then the post-modern "event attribution" methods would be unnecessary forbes.com/sites/rogerpie…
IPCC D&A methods have identified trends & causes in (many regions) for extreme temps & precip with various levels of confidence
But not tropical cyclones, floods, drought, tornadoes
So enter "event attribution" to fill the gap
Why? Explained below via NYT to win a PR battle
I can think of no other area of research where the relaxing of rigor and standards has been encouraged by researchers in order to generate claims more friendly to headlines, political advocacy and even lawsuits . . .
But there you go
/END
PS. There is an absolutely awesome STS dissertation to be written based on this thread. Career prospects might be limited though 😎
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The percentage of a percentage trick is increasingly common & leads to massive confusion
Here a undetectable difference of 0.01 events per year per decade is presented as the difference between a 31% and 66.4% increase (in the *likelihood* of the event, not the event itself)
The resulting confusion is perfectly predictable
Here is a reporter (NPR) explaining completely incorrectly:
"The phenomenon has grown up to 66% since the mid-20th century"
False
Also, the numbers in the text and figure do not appear to match up
I asked Swain about this over at BlooSkeye
A Frankenstein dataset results from splicing together two time series found online
Below is an example for US hurricane damage 1900-2017
Data for 1980-2017 was replaced with a different time series in the green box
Upwards trend results (red ---)
Claim: Due to climate change!
The errors here are so obvious and consequential that it is baffling that the community does not quickly correct course
The IPCC AR6 cited a paper misusing the Frankenstein hurricane loss dataset to suggest that NOAA's gold standard hurricane "best track" dataset may be flawed
JFC - Using flawed economic loss data to suggest that direct measurements of hurricanes are in error!
We’ve reached the point where an IPCC author is openly rejecting the conclusions of the IPCC out of concern over how their political opposition is correctly interpreting the AR6
The integrity of the IPCC on extreme events is now under attack
The IPCC explains that a trend in a particular variable is DETECTED if it is outside internal variability and judged with >90% likelihood
For most (not all) metrics of extreme weather detection has not been achieved
That’s not me saying that, but IPCC AR6
The IPCC also assesses that for most (but not all) metrics of extreme weather the signal of a change in climate will not emerge from internal variability with high confidence (ie, >90%) by 2050 or 2100, even assuming the most extreme changes under RCP8.5
The US National Academy of Sciences has a new study committee on Extreme Event Attribution
Among its sponsors are the Bezos Earth Fund and Robert Litterman
Who are they? . . .
The Bezos Earth Fund sponsors World Weather Attribution, an advocacy group promoting the connection of weather events w/ fossil fuels in support of press coverage & lawsuits
Robert Litterman is on the board of Climate Central which founded WWA & collaborates on climate advocacy
The fact that a NAS committee is funded by political advocates is crazy enough
But that is not all
On the committee itself are individuals from two climate advocacy groups
One . . . the Union of Concerned Scientists which is working to use attribution to support lawsuits . . .