Failed Predictions in Climate Science, Part 2: Mountain Ice

In my last post I covered one failed prediction having to do with Arctic sea ice. Here I'll cover two essentially failed predictions covering mountain glaciers. 

Mt. Kilimanjaro in 2017

Mt. Kilimanjaro 

Thompson et al 2002, a paper published in the prestigious journal Science[1], predicted that we should expect the remaining ice fields on Mt. Kilimanjaro to disappear sometime between 2015 and 2020.
Over the 20th century, the areal extent of Kilimanjaro's ice fields has decreased ∼80%, and if current climatological conditions persist, the remaining ice fields are likely to disappear between 2015 and 2020.
This prediction was featured in an Inconvenient Truth, so it gained a bit of attention, but by 2011, Mass Live reported that it was becoming clear that trends were not persisting as the study expected. By 2022, Politifact was writing factchecks about it, admitting this to be a failed prediction, but also (correctly) pointing out that this does not mean that climate science is all off base. Mt. Kilimanjaro's ice fields are still shrinking, even though it's taking longer for them to disappear than what was thought in 2002. I think that's fair. A study from 2024 found that 
While the extent in 1912 was mapped as 11.4 km^2, the remaining glacier area in November 2021 was only 0.98 km^2. Over the last century, all glaciers on Kilimanjaro have been retreating and some have vanished completely. 
In 2002, the areal extent of the ice fields had decreased by about 80%, but in 2021, it had decreased by 91.4%, so about half of the remaining ice fields had disappeared in about two decades. 

Himalayan Glaciers 

The IPCC-AR4 WG1 and WG2 reports made two conflicting claims about the disappearing of Himalayan glaciers. WG2 made the claim that 80% of Himalayan glacier area would likely disappear by 2035. This was a mistake. The proper analysis was found in WG1 chapter 4, which covered valid science on glaciers without the error from WG2. In fact, the one of the authors of WG1 chapter 4 (Georg Kaser) discovered the error. RealClimate reports on this that "The problem is that a WG2 chapter, instead of relying on the proper IPCC projections from their WG1 colleagues, cited an unreliable outside source in one place. Fixing this error involves deleting two sentences on page 493 of the WG2 report."

This second "failed prediction" is in my mind questionable as a failed prediction. It's definitely a mistake that needed correcting, but the correction was admitted and fixed long before 2035. But it was a mistake written as a prediction that was published in a peer-reviewed publication. So, in the spirit of generosity to contrarians, I'm deciding to include it, but I'm not going to give a full post to it. Mistakes and errors do occur, and they should be quickly corrected, but this doesn't seem to be as significant an error as Wadhams' or Thompson's predictions.

Significance

These three failed predictions are the only three failed predictions I have been able to find that 1) are made by mainstream climate scientists, 2) are published in the peer-reviewed literature, and 3) have demonstrably failed (or were corrected before failure). I know of no other predictions that meet these criteria. If someone alerts me to others, I'll be sure to acknowledge them. But it seems to be that this is actually a pretty good track record for climate science, especially given the contrarian rhetoric that all predictions of climate science failed (followed by a bunch of examples examples of sloppy reporting and/or misrepresentations of the scientific literature).

If climate science is operating properly, we'd expect about 5% of all predictions made with a 95% confidence level to fail. That is, we'd expect about 19 of 20 to come about as expected. I don't know how many scientific predictions have been made in the scientific literature, and I'm not going to try to research a total number. But I strongly suspect there have been more than 60 of these predictions published. If only 3 failed, then climate science is doing just fine. I think more importantly, none of these 3 failed predictions challenge any of the major conclusions of climate science or significantly alter our understanding of the physics of climate change. At best, these are lessons that we need to be reminded that short-term trends sometimes don't continue; sometimes climatological conditions don't persist linearly. 



References:

[1] Lonnie G. Thompson et al., Kilimanjaro Ice Core Records: Evidence of Holocene Climate Change in Tropical Africa.Science298,589-593(2002).DOI:10.1126/science.1073198

[2] Anne Hinzmann et al 2024 Environ. Res.: Climate 3 011003DOI 10.1088/2752-5295/ad1fd7

Comments

Post a Comment

Popular posts from this blog

Data Tampering by Shewchuk and Heller

Image
If you follow climate discussions on X, you're bound to see John Shewchuk and/or Tony Heller show graphs that reportedly show that NOAA is tampering with temperature data to fabricate global warming with spurious warming trends. I've gone over many of the reasons why this is nonsense before in posts about bias correction and so-called  ghost stations . I think it's good to show what's actually going on with the graphs they present as "proof" of data manipulation, though. I think it can be easily demonstrated here that it's actually Shewchuk and Heller that are tampering with data. Shewchuk (Top) and Correct (Below) Above are two graphs. The top graph shows what John Shewchuk claims shows that NOAA is manipulating data. It shows USHCN "raw" and "altered" Tmax data for 1900 to 2023. The bottom graph above is the correct plot of NOAA's published data from the current and correct dataset ( nClimDiv ) with a 5-year running mean to m...
Read more

Does NOAA have "Ghost Stations" for US Temperatures?

Image
The Epoch Times (ET) is a newspaper operated by the Falun Gong cult, formed in 1992. The cult has opposed the Chinese Communist Party, but recently it has made some inroads into the US politics, where it supports far-right political agendas; its ET newspaper has promoted a number of conspiracy theories involving QAnon, anti-vaccine propaganda, and climate science denial. In a recent " premium report ," the Epoch Times claims that the U.S. Temperature dataset operated by NOAA contains data from "non existent temperature stations" and asserts that there are "hundreds of ‘ghost’ climate stations" that are no longer operational, and data is just filled in from surrounding stations, with the implication that this is done to support Biden's climate policies. The tl;dr point here is that what the article calls "ghost stations" are actually just interpolated values used to calculate area-weighted means in an old dataset that NOAA no longer uses. The...
Read more

Was There a "Mike's Nature Trick" to "Hide the Decline?" Part 1 - Misreading CRU Emails

Image
In November 2009, someone likely stole[1] and publicly released over 1,000 emails from Climate Research Unit (CRU) at the University of East Anglia. Following this, people combed through all these emails  looking for evidence of frauds and coverups on the part of climate scientists. They found very little damaging information, but not everything they found was was good. There were, as best I can tell, four categories of content that were discovered: The normal kinds of communication you'd expect to find in correspondence between scientists Words and phrases that were twisted out of context and redefined to support an imagined conspiracy that had been imposed on the emails. Evidence of mean-spirited attacks on contrarian scientists and heavy-handed tactics intended to punish journals that published contrarian studies.  A single email describing the process of creating a graph for a WMO statement that used the phrase "hide the decline."  Here I plan to tackle the "hid...
Read more