Is Al Gore's An Inconvenient Truth accurate?
What the science says...
Select a level... | Basic | Intermediate | |||
Al Gore's film was "broadly accurate" according to an expert witness called when an attempt was made through the courts to prevent the film being shown in schools. |
Climate Myth...
Al Gore got it wrong
“Al Gore's Oscar-winning documentary on global warming, An Inconvenient Truth, was […] criticised by a high court judge who highlighted what he said were "nine scientific errors" in the film.
Mr Justice Barton yesterday said that while the film was "broadly accurate" in its presentation of climate change, he identified nine significant errors in the film, some of which, he said, had arisen in "the context of alarmism and exaggeration" to support the former US vice-president's views on climate change.” (The Guardian)
At a glance
An Inconvenient Truth is an award-winning documentary-style film that was released in September 2006, featuring the former U.S. Vice-president Al Gore. All about climate change, it was loved by many but vociferously loathed by some.
The film did contain a few errors, but that's not surprising given it was about climate science but created by a well-meaning politician. In reality, the reaction to it in certain quarters did a great deal to expose the simplistic mindset of the climate science denier. In their world, any error, however small, invalidates our entire understanding of how the planet works. It's like saying that because a single doctor misdiagnoses a condition, medicine should be abolished in its entirety.
Where were the errors? The most widely-circulated one involved snow and ice on Africa's highest mountain, Kilimanjaro (5,895 metres). At that height, even by the Equator, the temperatures around the summit rarely go above freezing. The error was in the claim that climate change had caused the shrinking of Kilimanjaro's ice-cap.
Comparing Kilimanjaro today to when the first explorers scaled it over 100 years ago shows that glacial retreat has certainly removed its ice-sheets by some 90%. The ice has however sublimed - gone from solid to vapour - something that often happens in the very dry cold air that is typical of the local high-altitude climate there. In the rainy seasons that occur there twice a year, snow does fall, sometimes copiously, but the sublimation process is in overall charge at present.
But that's a minor error when one considers all of the vast numbers of retreating mountain glaciers in the mid-latitudes and the huge meltwater torrents gushing from their ends. That those glaciers are retreating due to the warming climate is widely accepted by those who study them.
Other errors concerned timing of future changes, giving an impression of imminent chaos. But does that matter? Not really. If you know the oceans are going to rise by several metres, whether that takes 50, 100 or 200 years is something of a distraction. We know from the deglaciation after the last ice-age that under some circumstances, sea level can rise by around four metres per century. So we have a feel for what's possible if warming continues unchecked. Even if the seas rise by a tenth of that figure by 2100, it's still seriously bad news.
In other words, we're storing up massive problems for our children, grandchildren and their descendents. To ignore that because a politician once annoyed you is to casually write off their futures. Is that the best we can do?
Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!
Further details
Al Gore, certainly one of the most vilified proponents of climate science anywhere in the world, earned most of this enmity through the success of a film he presented called An Inconvenient Truth (2006), hereafter AIT. The film was a staid presentation of climate science to date, a round-up of research, science and projections, with many cinematic sequences employed to harness the power of the medium. It was meant to shock, because those of us who fully understand what's going on with the climate find it shocking that we're allowing this to happen to our beloved Earth.
The majority of the film, covering issues like Himalayan Glaciers, Greenland and Antarctica losing ice, the severity of hurricanes and other weather phenomena, was accurate and represented the science as it stood. Since the release of the film, considerably more evidence has been found in support of the science and projections in the film.
One erroneous claim by Gore was to infer that global warming had caused the shrinking of the ice-sheets around the summit of Mount Kilimanjaro. Glaciologists who study the mountain instead consider the massive (90%) ice-loss on its heights to be predominantly caused by sublimation in the very cold and dry air, frequent windy conditions and high incident UV light at that altitude (Kaser et al. 2004), together with insufficient snowfall to keep the ice topped-up (fig. 1). A good explanation of the phenomenon is available in a 2007 article published in American Scientist, by Philip Mote and Georg Kaser (PDF available at the time of writing at Researchgate).
Fig. 1: the distinctively fluted ice-cliffs high on Kilimanjaro. Ice-ablation here predominantly occurs due to its sublimation into the dry, cold air with high incident UV light - unlike most mountain glaciers around the world. Image: James Heilman via Wikipedia, licensed under Creative Commons Attribution-Share Alike 3.0 Unported licence.
The pattern of deglaciation on Kilimanjaro, still ongoing, differs from that of the numerous mid-latitude mountain glaciers around the world, that are without doubt mostly retreating due to ice-melt in a warmer climate. In addition, a lot of the Kilimanjaro ice-loss occurred well before the steepening in global warming after the 1970s. In that respect, Kilimanjaro is a bit special. Unfortunately it's also an iconic mountain, which is probably why Gore picked it. An error, but an understandable one for a politician to make.
If Gore had asked, he would likely have been advised to turn his attention to some other iconic mountains, such as the well known European Alpine peaks, the Matterhorn and Mt Blanc. Warming has been problematic in the Alps for years now and is getting worse: in the hot, dry summer of 2022, both of these and some other peaks saw huts closed down and mountain guides cancelling bookings. The main risk was rockfall due to the permafrost that "glues" the rock together melting away. The story was covered widely in the media, including a good objective account at the UK Climbing news website here.
Many of the other errors were of a more political theme. Most involved sea level rise which as readers will know is a slow process: currently the rate is around 3.6 millimetres per year but it is accelerating. Gore showed slides of some of those typical flood-maps that depict the effects of different amounts of sea level rise and kind of implied these inundations could happen very soon. That's straying into politics in that Gore realised he had to shock to get the message across.
Nevertheless, 3.6mm a year equates to 36 centimetres a century and that is the bare minimum that can be expected because of that acceleration. We know what's possible from looking at the past: for example in Meltwater Pulse 1A, some 14,600 years ago, sea levels are widely considered to have risen by 20 metres in just 500 years (Lin et al. 2021).
Once processes such as ice-sheet collapse get underway, they are near-impossible to stop. That means that having beach-front property at the moment (something Gore is often accused of) should be fine unless a big hurricane makes landfall in your neighbourhood (bad luck). But it would be inadvisable to consider such a residence as a long-term, intergenerational investment to be enjoyed for centuries. For many parts of the world, assuming for a moment that we fail to curb emissions, sea level rise only becomes a massive problem over the decades and centuries to come: nevertheless it is an appalling legacy to leave to future generations.
Last updated on 11 June 2023 by John Mason. View Archives
I am astounded to see point 8 ("that coral reefs were bleaching because of global warming") included as an 'error'. I'd suggest you could safely add that one to the list of what Al got right. Yes, there are other factors that cause corals to bleach, but mass coral bleaching is accepted to occur as a result of higher-than-normal sea temperatures resulting from global warming. Leaving it to the experts: "The primary cause of mass coral bleaching is increased sea temperatures. At a local scale, many stressors including disease, sedimentation, cyanide fishing, pollutants and changes in salinity may cause corals to bleach. Mass bleaching, however, affects reefs at regional to global scales and cannot be explained solely by localised stressors operating at small scales. Rather, a ontinuously expanding body of scientific evidence indicates that such mass bleaching events are closely associated with large-scale, anomalously high sea surface temperatures. Temperature increases of only 1-2ºC can trigger mass bleaching events because corals already live close to their maximum thermal limits." (Marshall and Schuttenberg, 2006) Re: bleaching, climate change and temperature, the Australian Institute of Marine Science simply states: What is known: - Global climate is changing rapidly due to human activities and will result in continued rising temperatures both on land and in the sea. - Climate change due to the enhanced greenhouse effect has significant consequences for coral reefs. There is a direct link between unusually warm seawater temperature and bleaching of reef-building corals around the world. (http://www.aims.gov.au/pages/search/search-coral-bleaching.html) Some overviews of bleaching science containing dozens of references to the primary literature: Johnson JE and Marshall PA (editors) (2007) Climate Change and the Great Barrier Reef LINK In particular, see Chapter 10: Hoegh-Guldberg O, Anthony K, Berkelmans R, Dove S, Fabricus K, Lough J, Marshall P, van Oppen MJH, Negri A and Willis B (2007) Chapter 10 Vulnerability of reef-building corals on the Great Barrier Reef to Climate Change. In Climate Change and the Great Barrier Reef, eds. Johnson JE and Marshall PA. Great Barrier Reef Marine Park Authority and Australian Greenhouse Office, Australia Marshall and Schuttenberg (2006) "A Reef Manager's Guide to Coral Bleaching", Great Barrier Reef Marine Park Authority. LINK A few useful links: Great Barrier Reef Marine Park Authority (what is coral bleaching) LINK NOAA Coral Reef Watch (satellite based sea temperature monitoring for coral bleaching prediction) http://coralreefwatch.noaa.gov/satellite/index.html Status of Coral Reefs of the World http://www.aims.gov.au/pages/research/coral-bleaching/scr2004/
Seems to me that the issues such as Antarctica, Greenland and the Himalaya's are indicative only of warming, which I believe is well supported by empiral evidence. But that alone does not necessarily mean that mankind has caused it.
[PS] Noone is claiming that it does. Please use the "arguments" menu item, "taxonomy" and look under the "its not us" section. Alternatively, read the "attribution" chapters of the IPCC WG1 reports to see where the evidence comes from.
Further to 'foram' it's interesting in the wake of President Trumps withdrawal from the Kyoto Agreement that a news bulleting about coral reefs dying worldwide has appeared on the Al Jazeera network in Australia this morning - complete with heart tugging segments of local fishermen.
Iocc @16 , on the contrary , a large conference of coral reef experts (gathering in Hawaii) in mid-2016 expressed grave concern about the fate of coral reefs worldwide. And individual reef experts have been pointing to the impending destruction of coral reefs, for many years now.
All this was well before Mr Trump was anybody worth paying attention to.
The by-now unavoidable death of coral reefs is merely a part (but a spectacularly obvious part) of the corner that we have painted ourselves into, regarding the slow-building crisis of global warming.
iocc @16, do you have a link. The most recent Al Jazeera article on coral I can find is from May 7th.
I really can't think of a worse spokesman for a scientific cause than a politician.
Scott0119, you're getting it wrong. The scientific cause does not need any spokesman. There is no scientific "cause." The science is what it is. The weight of the evidence is what it is and anyone who can think who looks at the evidence will see the direction where it points. Attacks on the science are nothing but pitiful hogwash and that becomes evident after ony a few hours of researcing the subject. We're talking scientific evidence here, not courthouse BS.
Only those with unsolvable cognitive dissonance or an overwhelming emotional attachment to ideology can fail to see the reality. These people can not be convinced, no matter how hard reality will hit them on the head, because having their belief system fail is more threatening emotionally than any adverse consequence of holding said belief system.
There are powerful interests with no other preoccupation than monetary profit that are muddyying the water to obscure the public perception but they are not challenging the science in any convincing way. They use mind manpulation methods and boatloads of BS, which has now been brought to an art form, and benefit from means of dissemination unprecedented in human history. When they do science, like Exxon did for a while, they find exactly the same stuff as the independent science. It's not the science who needs a spokesman, it's us, as a society, trying to avoid some very costly and very uncontrollable changes in the physical world where we live. The kind of changes that will dwarf the costs, human, financial and others, that would be brought by a true, in depth, energy conversion.
It is rather ironic that the most strident voices in this non debate come from the richest of the rich, who essentially scream that they must have even more money, while some poorer nations are ready to make sacrifices for the sake of long term viability, even as they are the ones who can afford it the least. This world has gone far beyond anything imagined by science fiction authors of old, even in their wildest stories. People are awash in a prosperity that has no precedent, while believing that prosperity is still a goal they have to reach. A world where the richest earn more in an hour than others (not even below poverty line) do in a year, but where these richer ones can't be bothered to ensure the continued livability of the whole thing.
Meanwhile, the majority of the population is so scientifically illiterate, so unable to think quantitatively, so unaware of mind manipulation methods, that they respond to such methods with the certainty of a machine having a button pushed. Some weird cargo cult we have become...
@phillipe chantreau @20...wow! I guess I hit a nerve? Let me just end this by agreeing with you.."youre getting it wrong" that should end the tyraid.
[PS] Enough please. This topic is for discussion of whether Al Gore got the science wrong nothing else.
@ moderator...is this directed at both of us or just me?
[JH] Moderation complaint snipped.
Please note that posting comments here at SkS is a privilege, not a right. This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.
Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter.
[PS] To everyone. Discuss only the science here.
[DB] Per user request, posting rights rescinded.