Archives par mot-clé : IPCC

Evolutions récentes du CO2 atmosphérique (3/4)

by J.C. Maurin, 12 novembre 2018 in  ScienceClimatEnergie

L’IPCC (GIEC en français) fut créé en 1988 par l’UNEP (United Nations Environment Programme) et le WMO (World Meteorological Organization). Dans les principes régissant les travaux du GIEC (1) on lit : Le GIEC a pour mission d’évaluer … les risques liés au changement climatique d’origine humaine.  Le GIEC respecte son propre principe fondateur : il attribue l’intégralité de la hausse du taux de CO2 depuis 1958 à une cause anthropique. Nous examinerons ici le modèle anthropique du GIEC et nous le confronterons aux mesures contemporaines, puis à un modèle mixte. Cet article fait suite aux deux précédents publiés sur le site SCE au cours des mois de septembre (1/4) et octobre 2018 (2/4).

C.4.  Conclusions

  • Un modèle qui décrit un monde fixe, en équilibre, un modèle où l’homme est central, un modèle qui parvient à reproduire certaines observations mais pas toutes, un modèle unanimement soutenu par les autorités politiques ou morales, enfin un modèle qui pose a priori un principe intangible… est le type même de modèle qui fut développé  par Ptolémée (6) pour le système solaire. Ce modèle fut jadis l’objet d’un consensus  à  > 97%.

  • L’atmosphère actuelle comporte environ 20 ppm de CO2 anthropique correspondant à 20/400 soit 5% du CO2 atmosphérique. En un siècle les hommes ont donc modifié la composition de l’atmosphère de 20 ppm soit 0,002% : sur ce sujet également, il semble que nous ne soyons pas au centre du monde.

  • Les évolutions récentes du CO2 atmosphérique ne peuvent pas avoir une cause uniquement anthropique: les observations du δ13C l’interdisent. Les causes sont anthropiques et naturelles. Le modèle purement anthropique du GIEC est donc à rejeter.

The Economics of the IPCC’s Special Report on Limiting Temperatures to 1.5 °C

by Ken B. Gregory, P. Eng., October 31, 2018 in FriendsofScience

The Intergovernmental Panel on Climate Change (IPCC) published a special report (hereafter called SR15) on the impacts of global warming of 1.5 °C above pre-industrial levels on October 8, 2018. The report says the cost of mitigating CO2 emissions in 2030 to prevent temperatures from exceeding 1.5 °C above pre-industrial levels is about 880 US$2010 per tonne of CO2 ($/tCO2). The benefit of doing so, according to the report, is 15 $/tCO2. Using a climate sensitivity based on observations including effects of natural climate change, urban warming and the best available economic model, the mitigation proposal will prevent a benefit of 8.2 $/t CO2, for a total loss of 888 $/tCO2 mitigated. In other words, each $1000 spent on mitigation of CO2 emissions will cause another loss $9.20.

The SR15, presents various emissions pathways to limit the projected rise of temperatures from pre- industrial times, estimated to be the temperature average from 1850 to 1900, to the year 2100, and to limit the temperature rise to 2.0 °C by 2100. According to the IPCC, temperatures have increased by about 1.0 °C from pre-industrial times to 2017. Therefore, the emissions pathways to limit warming allows only 0.5 °C temperature rise from 2017, assuming there is no natural caused climate change.

See also here

REBUTTAL: IPCC SR15 Climate Change Report is Based on Faulty Premises

by Anthony Watts, October 31, 2018 in WUWT

Friends of Science Society is critical of the IPCC SR15 report, pointing out the following:

  1. We are in the Meghalayan, not the Anthropocene. The IPCC SR15 report claims to view climate change through “the lens of the Anthropocene.” This term is popularly used to describe a modern geological period wherein humans are assumed to have a larger impact on the world than nature. On July 13, 2018, the International Union of Geological Sciences (IUGS) issued a statement that the earth is now in the Meghalayan, a period that began 4,200 years ago.  In response to questions as to why the term “Anthropocene” had not been included, at least for the past 50 years of presumed human influence, the IUGS responded that the term “Anthropocene” has not even been submitted for consideration and that the term has only sociological, not scientific relevance.  The IPCC should not use this ‘lens.’

  2. All climate models (simulations) used by the IPCC run ‘too hot’ versus observations. The computer simulations project future warming (thus being the rationale for global warming climate policies) show significantly higher temperatures than what is being observed. Only the Russian climate model and satellite/weather balloon data closely match present temperatures in the lower troposphere. This suggests that most climate models ascribe too great an effect of warming (climate sensitivity) to carbon dioxide.

    This means the climate models should not be used to set public policy.

  3. No temperature can be accurately measured to a precision of less than ±0.1°C. global temperature data is a metric of averaged and adjusted data from many sources, suggesting that a 0.5°C difference in temperature is moot and an arbitrary figure. It does not reference an actual measurement of earth’s temperature; people are being misled.


by David Whitehouse, October 29, 2018 in GWPF

The IPCC appears to have secretly changed the definition of what constitutes ‘climate’ by mixing existing and non-existing data

The definition of ‘climate’ adopted by the World Meteorological Organisation is the average of a particular weather parameter over 30 years. It was introduced at the 1934 Wiesbaden conference of the International Meteorological Organisation (WMO’s precursor) because data sets were only held to be reliable after 1900, so 1901 – 1930 was used as an initial basis for assessing climate. It has a certain arbitrariness, it could have been 25 years.

For its recent 1.5°C report the IPCC has changed the definition of climate to what has been loosely called “the climate we are in.” It still uses 30 years for its estimate of global warming and hence climate – but now it is the 30 years centred on the present.


by GWPF, October 18, 2018 TheWallStreetJournal

In case you hadn’t heard we’re all doomed, yet the world mostly yawned. This is less complacency than creeping scientific and political realism.

The U.N. panel says the apocalypse is nigh—literally. According to its calculations, global carbon emissions must fall 45% by 2030—twice as much as its earlier forecasts—and the world must wean itself entirely off fossil fuels over three decades to prevent a climate catastrophe that will include underwater coastlines and widespread drought and disease.

These reductions are “possible within the laws of chemistry and physics,” said the report’s co-author Jim Skea, and that’s a relief. But he added: “Doing so would require unprecedented changes,” and the report said some methods “are at different stages of development and some are more conceptual than others, as they have not been tested at scale.”

IPCC achieves net zero credibility

by Barry Brill, October 14, 2018 in WUWT

The recently released IPCC SR15 reports (at A1) that global warming is likely to reach 1.5°C between 2032 and 2050 and (at B) will probably bring species extinction, weather extremes and risks to food supply, health and economic growth. If we are to avoid this, net CO2 emissions will need to decline by about 45% from 2010 levels by 2030, reaching net zero by 2050 (C1), followed by extensive removals (C5). The required energy investment alone will be $2.4 trillion per year.

Is this possible?

As at 2015, which was not materially different from 2010, more than half the planet’s total CO2 emissions (36Gt) were sourced from just three countries:


Richard Lindzen Lecture at GWPF: ‘Global Warming for the Two Cultures’

by R. Lindzen, Ocotber2, 208 in A. Watts, WUWT

The climate system

The following description of the climate system contains nothing that is in the least controversial, and I expect that anyone with a scientific background will readily follow the description. I will also try, despite Snow’s observations, to make the description intelligible to the non-scientist.


So there you have it. An implausible conjecture backed by false evidence and repeated incessantly has become politically correct ‘knowledge,’ and is used to promote the overturn of industrial civilization. What we will be leaving our grandchildren is not a planet damaged by industrial progress, but a record of unfathomable silliness as well as a landscape degraded by rusting wind farms and decaying solar panel arrays. False claims about 97% agreement will not spare us, but the willingness of scientists to keep mum is likely to much reduce trust in and support for science. Perhaps this won’t be such a bad thing after all – certainly as concerns ‘official’ science.

There is at least one positive aspect to the present situation. None of the proposed policies will have much impact on greenhouse gases. Thus we will continue to benefit from the one thing that can be clearly attributed to elevated carbon dioxide: namely, its effective role as a plant fertilizer, and reducer of the drought vulnerability of plants. Meanwhile, the IPCC is claiming that we need to prevent another 0.5◦C of warming, although the 1◦C that has occurred so far has been accompanied by the greatest increase in human welfare in history. As we used to say in my childhood home of the Bronx: ‘Go figure’.

Most US newspapers failed to even mention the new IPCC climate change report

by Meteor Blades, October 11, 2018 in RedGreen&Blue

Media Matters scrutinized the top 50 U.S. newspapers between 9 AM and noon ET on Monday and found most did not mention on their website homepages the Intergovernmental Panel on Climate Change’s Sunday release of its report on the devastating impacts of a global temperature increase of 1.5-degree Celsius (2.7-degree Fahrenheit) above the temperature of the pre-industrial era.

IPCC Now Claims All Warming Since End Of Little Ice Age Is Man-Made

by B. Peiser, October 10, 2018 in ClimateChangeDispatch

So the very first sentence of the SR15 Summary for Policy Makers, after the Introduction, consists of a statement which is not well supported by the totality of the available scientific literature and which is at odds with the IPCC’s own findings in the AR5 Working Group 1 Report of just 5 years ago! Not a good start. —Climate Scepticism, 9 October 2018


IPCC Pretends the Scientific Publishing Crisis Doesn’t Exist

by Donna Laframboise, October 7, 2018 in BigPictureNews

The Intergovernmental Panel on Climate Change (IPCC) issued a press release today. It tells us the IPCC assesses “thousands of scientific papers published each year,” and that its latest report relies on “more than 6,000 references.”

We therefore have no earthly reason to imagine that climate science is exempt from these kinds of problems.

If half of the scientific literature is untrue, it therefore follows that half of climate research is also untrue.

This means that 3,000 of the IPCC’s 6,000 references aren’t worth the paper they’re written on.

Climate Bombshell: Global Warming Scare Is Based on ‘Careless and Amateur’ Data, Finds Audit

by James Delingpole, October 6, 2018 in NotaLotofPeopleKnowThat

HadCRUT4 is the primary dataset used by the Intergovernmental Panel on Climate Change (IPCC) to make its dramatic claims about “man-made global warming”, to justify its demands for trillions of dollars to be spent on “combating climate change” and as the basis for the Paris Climate Accord.

But according to a groundbreaking analysis by Australian researcher John McLean it’s far too sloppy to be taken seriously even by climate scientists, let alone a body as influential as the IPCC or by the governments of the world.

“It’s very careless and amateur,” he says. “About the standard of a first-year university student.”

Among the many errors found by McLean were:

  • Large gaps where there is no data and where instead averages were calculated from next to no information. For two years, the temperatures over land in the Southern Hemisphere were estimated from just one site in Indonesia.

  • Almost no quality control, with misspelled country names (‘Venezuala” “Hawaai” “Republic of K” (aka South Korea) and sloppy, obviously inaccurate entries.

  • Adjustments – “I wouldn’t be surprised to find that more than 50 percent of adjustments were incorrect,” says McLean – which artificially cool earlier temperatures and warm later ones,  giving an exaggerated impression of the rate of global warming.

  • Methodology so inconsistent that measurements didn’t even have a reliable policy on variables like Daylight Saving Time.

  • Sea measurements, supposedly from ships, but mistakenly logged up to 50 miles inland.

  • A Caribbean island – St Kitts – where the temperature was recorded at 0 degrees C for a whole month, on two occasions (somewhat implausibly for the tropics)

  • A town in Romania which in September 1953, allegedly experienced a month where the average temperature dropped to minus 46 degrees C (when the typical average for that month is 10 degrees C).

At IPCC talks Trump Administration emphasizes scientific “uncertainty” and “value of fossil fuels”… MAGA!

by David Middleton, October 4, 2018 in WUWT

95% of the model runs predicted more warming than the RSS data since 1988… And this is the Mears-ized RSS data, the one in which the measurements were influenced to obtain key information (erase the pause and more closely match the surface data).

Their “small discrepancy” would be abject failure in the oil & gas industry.

The observed warming has been less than that expected in a strong mitigation scenario (RCP4.5).

Output of 38 RCP4.5 models vs observations.   The graph is originally from Carbon Brief.  I updated it with HadCRUT4, shifted to 1970-2000 baseline, to demonstrate the post-El Niño divergence.

What is the Meaningful 97% in the Climate Debate?

by Tim Ball, September 29, 2018 in WUWT

In media interviews or discussions with the public, the most frequent opening challenge is; “But don’t 97% of scientists agree?” It is usually said obliquely to imply that you know a lot, and I don’t understand, but I assume you are wrong because you are in the minority. I don’t attempt to refute the statistics. Instead, I explain the difference in definitions between science and society. Then I point out that the critical 97% figure is that at least 97% of scientists have never read the claims of the IPCC Reports. How many people reading this article have read all the IPCC Reports, or even just one of them? If you have, it is probably the deliberately deceptive Summary for Policymakers (SPM). Even fewer will have read the Report of Working Group I: The Physical Science Basis. Naively, people, especially other scientists, assume scientists would not falsify, mislead, misrepresent, or withhold information. It is worse, because the IPCC deliberately created the false claim of consensus.