Arguments
Is Al Gore's An Inconvenient Truth accurate?
What the science says...
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While there are minor errors in An Inconvenient Truth, the main truths presented - evidence to show mankind is causing global warming and its various impacts is consistent with peer reviewed science. |
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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)
It's worth pointing out that Al Gore is a politician, not a climate scientist. Debunking Gore does not disprove anthropogenic global warming. Nevertheless, it is instructive to look at the purported errors in An Inconvenient Truth as it reveals a lot about climate science and the approach of his critics.
What Al got right
Retreating Himalayan Glaciers
Contrary to James Taylor's article, the American Meteorological Society's Journal of Climate never said growing glaciers are "confounding global warming alarmists" - that's a quote from the Heartland Institute website written by... James Taylor. He's actually quoting himself and attributing it to the AMS! To put the Himalayas in context, the original AMS study is not refuting global warming but observing anomalous behaviour in a particular region, the Karakoram mountains. This region has shown short term glacier growth in contrast to the long term, widespread glacier retreat throughout the rest of the Himalayas due to feedback processes associated with monsoon season. Overall, Himalayan glaciers are retreating - satellite measurements have observed "an overall deglaciation of 21%" from 1962 to 2007. In essence, the Karakoram glaciers are the exception that proves the rule.
Greenland gaining ice
Re Greenland, a big clue is the study's title: Recent Ice-Sheet Growth in the Interior of Greenland. The study finds increasing ice mass in the interior due to heavier snowfall - an expected side-effect of global warming - and doesn't factor in all the melting that occurs at the edges of the ice sheet. Overall, Greenland is losing ice according to satellite measurements here, here and here.
Antartica cooling and gaining ice
Antarctic cooling is a uniquely regional phenomenon. The original study observed regional cooling in east Antarctica. The hole in the ozone layer above the Pole causes increased circular winds around the continent preventing warmer air from reaching eastern Antarctica and the Antarctic plateau. The flip side of this is the Antarctic Peninsula has "experienced some of the fastest warming on Earth, nearly 3°C over the last half-century". While East Antartica is gaining ice, Antartica is overall losing ice. This is mostly due to melting in West Antarctica which recently had the largest melting observed by satellites in the last 30 years.
Hurricanes
The dispute isn't that global warming is causing more hurricanes but that it's increasing their severity and longevity.
What Al got wrong
Mount Kilimanjaro
Indeed deforestation seems to be causing Mount Kilimanjaro's shrinking glacier so Gore got this wrong. In his defence, the study by Philip Mote came out after Gore's film was made. But Mote puts it in perspective: "The fact that the loss of ice on Mount Kilimanjaro cannot be used as proof of global warming does not mean that the Earth is not warming. There is ample and conclusive evidence that Earth's average temperature has increased in the past 100 years, and the decline of mid- and high-latitude glaciers is a major piece of evidence."
Dr Thompson's thermometer
Al Gore refers to a graph of temperature, attributing it to Dr Thompson . The graph is actually a combination of Mann's hockey stick (Mann et al. 1998) and CRU's surface measurements (Jones et al. 1999). However, the essential point that temperatures are greater now than during the Medieval Warm Period is correct and confirmed by multiple proxy reconstructions. More on Dr Thompson's thermometer...
An Inconvenient Truth - the court case
Gore's film has also drawn criticism on the grounds that it featured in a UK court case. The case, heard in the High Court in September 2007, was brought by a school governor against the Secretary of State for Education, in an attempt to prevent the film being distributed to schools. Mr. Justice Burton, in his judgement, ordered that teaching notes accompanying the film should be modified to clarify the speculative (and occasionally hyperbolic) presentation of some issues. However the broad theme was one he agreed with. About the film in general, he said this:
17. I turn to AIT, the film. The following is clear:
i) It is substantially founded upon scientific research and fact, albeit that the science is used, in the hands of a talented politician and communicator, to make a political statement and to support a political programme.
ii) As Mr Chamberlain persuasively sets out at paragraph 11 of his skeleton:
"The Film advances four main scientific hypotheses, each of which is very well supported by research published in respected, peer-reviewed journals and accords with the latest conclusions of the IPCC:
(1) global average temperatures have been rising significantly over the past half century and are likely to continue to rise ("climate change");
(2) climate change is mainly attributable to man-made emissions of carbon dioxide, methane and nitrous oxide ("greenhouse gases");
(3) climate change will, if unchecked, have significant adverse effects on the world and its populations; and
(4) there are measures which individuals and governments can take which will help to reduce climate change or mitigate its effects."
These propositions, Mr Chamberlain submits (and I accept), are supported by a vast quantity of research published in peer-reviewed journals worldwide and by the great majority of the world's climate scientists.
The judge did identify the errors discussed above and ordered that qualifications on the science and on its political implications should be included in the guidance notes for teachers. But whatever the deniers may claim, Al Gore was not involved in the case, was not prosecuted, and because the trial was not a criminal case, there was no jury, and no guilty verdict was handed down.
In a sense, one can look back and see that the court case was a snapshot of the climate - the political one, not the scientific one - in the mid 2000s. For those interested in such things, David Roberts at Grist did a good write-up of this particular storm in a tea-cup here. The full and lengthy high court judgement can be read here.
To conclude, the lesson here is that errors, concerning the minute details about the effects of climate change in various places, in no way discredit the vast body of hard evidence that climate change is happening, is caused by our relentless carbon emissions and is having adverse effects that will only get worse through time if we do nothing about it.
Note June 11, 2023: The intermediate version of the rebuttal was updated with the details about the court case ruling when we added the at-a-glance section to and updated the basic version.
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.
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[PS] To everyone. Discuss only the science here.
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