FACT: IPCC Reiterates That The World Is Warming

MYTH: The IPCC Now Says The World Is Cooling

• A Washington Times editorial claimed the IPCC's fifth assessment report “is said to admit that the planet has been cooling, not warming.” [Washington Times, 9/5/13]
• In an editorial titled “United Nations' Panel Admits Global Cooling?,” Investor's Business Daily asked “on what, we wonder, will the IPCC blame the coming cooling period.” The editorial continued that The IPCC itself was “reportedly” predicting such a period. [Investor's Business Daily, 9/9/13]
• The Washington Examiner claimed that a leaked draft of the IPCC report “says that the world is not warming but actually cooling, and will continue to get colder until the middle of the century.” [Washington Examiner, 9/9/13]
• On The Five, Greg Gutfeld cited the Daily Mail to claim that “A leaked report ... has led scientists to the fact that the country [sic] will be cooling until the middle of the century.”  He later added, “That's from the U.N. Intergovernmental Panel on Climate Change.” [Fox News, The Five, 9/10/13 via Nexis]

IPCC: Warming Is “Unequivocal.” The IPCC's Summary for Policymakers (SPM), which was released on Friday in advance of the full report, reports that “Warming of the climate system is unequivocal”:

Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, sea level has risen, and the concentrations of greenhouse gases have increased.

[...]

Each of the last three decades has been successively warmer at the Earth's surface than any preceding decade since 1850.

 The summary included this chart showing annual and decadal temperatures:

[IPCC, 9/27/13]

IPCC Projects Warming To Continue. The IPCC concluded that the world will continue to warm under all emissions scenarios as seen in this Wall Street Journal graphic -- even one in which carbon emissions are cut aggressively (Scenario 1).

The IPCC stated further that “Most aspects of climate change will persist for many centuries even if emissions of CO2 are stopped. This represents a substantial multi-century climate change commitment created by past, present and future emissions of CO2.” [IPCC, 9/27/13] [Wall Street Journal, 9/27/13]

IPCC Now 95% Certain This Warming Is Being Caused By Man. The fifth assessment states that “Climate models have improved since the [2007 version]” and human influence is now thought “extremely likely” -- representing 95 percent certainty - to be the dominant cause of global warming since the mid-20^th century. As reported by The Economist:

The report is more definitive than in the past about the role of people in causing climate change. It say that it is “extremely likely”--IPCC speak for having a probability of over 95%--that man is responsible. This contrasts with the tentative tone of the early IPCC reports. “The observed increase [in surface air temperatures] could be largely due to this natural variability,” said the first one, in 1990. The next report in 1995 merely suggested a link between rising temperatures and human activity. That link was deemed “likely” (which means probability of 66%) in 2001, and “very likely” (90%) in 2007.

[IPCC, 9/27/13] [The Economist, 9/27/13]

FACT: The Report Summary Directly Addresses Short-Term Temperature Trends

MYTH: The IPCC Doesn't Mention The Temperature “Pause”/Speed Bump

• In a Washington Times op-ed, Paul Driessen claimed the IPCC “deleted all references to the 17-year temperature standstill.” [Washington Times, 9/30/13]
• Washington Examiner columnist Ron Arnold said that after Marc Morano, who promotes climate misinformation at the website Climate Depot, told him a list of claims supposedly casting doubt on climate change including that “Global temperatures have failed to rise for 15-plus years,” Arnold complained that “none of that was in the IPCC report.” [Washington Examiner, 9/20/13]
• NewsBusters reported on “allegations” that “IPCC scientists are trying to avoid including the temperature hiatus in their report.” [NewsBusters, 9/25/13]
• A FoxNews.com article published the day of the SPM release claimed the IPCC “could not explain” why temperatures over the prior 15 years have “stopped rising.” [FoxNews.com, 9/27/13]

Natural Variability Tied To Short-Term Trends. On the third page of the Summary for Policymakers (SPM), the IPCC noted that the warming trend over the prior 15 years was about 0.05°C (0.09°F) per decade, but that this relatively minor warming does “not in general reflect long-term climate trends”: 

In addition to robust multi-decadal warming, global mean surface temperature exhibits substantial decadal and interannual variability (see Figure SPM.1). Due to natural variability, trends based on short records are very sensitive to the beginning and end dates and do not in general reflect long-term climate trends. As one example, the rate of warming over the past 15 years (1998-2012; 0.05 [-0.05 to +0.15] °C per decade), which begins with a strong El Niño, is smaller than the rate calculated since 1951 (1951-2012; 0.12 [0.08 to 0.14] °C per decade)

[...]

The observed reduction in surface warming trend over the period 1998-2012 as compared to the period 1951-2012, is due in roughly equal measure to a reduced trend in radiative forcing and a cooling contribution from internal variability, which includes a possible redistribution of heat within the ocean (medium confidence). The reduced trend in radiative forcing is primarily due to volcanic eruptions and the timing of the downward phase of the 11-year solar cycle.

The Natural Resources Defense Council's Dan Lashof explained at The Huffington Post:

Natural variability and short term factors, such as volcanoes, always have and always will cause year-to-year variations in the climate. That means that the shorter the time period you look at, the larger the uncertainty in determining any trend, and the more sensitive the result to the starting point. Again, the IPCC report makes this clear: “Due to natural variability, trends based on short records are very sensitive to the beginning and end dates and do not in general reflect long-term climate trends.”

Specifically, the uncertainty bounds on the 15-year trend starting in 1998 (the period of the claimed slowdown) range from -0.05 degrees per decade to +0.15 degrees per decade, which encompasses the central estimate of the warming trend since 1950 of 0.12 degrees per decade. That's what statistically insignificant means. Moreover, if you look at a 15 year trend starting in 1995, rather than 1998, the trend estimate is +0.02 to +0.24 degrees per decade, which is FASTER than the overall trend since 1950

[IPCC, 9/27/13] [Huffington Post, 9/27/13]

Short-Term “Speed Bump” Does Not Contradict Long-Term Trend. In a blog post for the Union of Concerned Scientists, climate scientist Brenda Ekwurzel explained that short-term temperature trends of lesser warming are merely a “speed bump,” chiefly caused by ocean heat absorption and other factors, and a precursor to long-term waming:

Even as a car slows down to go over a “speed bump,” there is no question the car is still advancing down the road. Similarly, the global average surface temperature trend of late is like a “speed bump” and we would expect the rate of temperature increase to speed up again just as most drivers do after clearing the speed bump.

We keep getting questions about this air temperature trend that has more to do with where the excess heat is primarily going -- the ocean -- and the rate at which heat transfers to the deep ocean, as well as other factors that can temporarily offset the influence of heat-trapping gases. These include ocean cycles such as phases of the El Niño Southern Oscillation in the Pacific Ocean. Or tiny pollution particles as well as tiny particles emanating from volcanic eruptions that reflect sunlight. 

More importantly, society tends to focus quite heavily on the surface temperature since that is where most of us live our daily lives. We know that is just one of the many ways we measure climate change. A look at the big picture shows a world that continues to face disruption from human-induced climate change. 

Indeed, a chart published in the SPM showing comparisons of observed and simulated temperature anomalies still reflects long-term warming:

[Union of Concerned Scientists, 9/25/13] [IPCC, 9/27/13]

FACT: Actual Temperatures Consistent With IPCC Projections

MYTH: Recent Temperatures Show IPCC Models Useless

• Numerous conservative outlets seized on a Mail on Sunday article, titled “Global warming is just HALF what we said,” that claimed a leaked IPCC draft said the temperature was rising at just half the rate predicted in the 2007 IPCC report. [The Mail on Sunday, 9/14/13] [Hot Air, 9/16/13] [Investor's Business Daily, 9/17/13]
• Washington Examiner columnist Ron Arnold claimed that the report would offer the “stunning concession” that “that computer-modeled forecasts of imminent planetary catastrophe were catastrophically wrong.” [Washington Examiner, 9/20/13]
• The Washington Free Beacon reported that critics of the IPCC report say that “their skepticism is based on discrepancies between the UN's climate models and actual, observable conditions”. [Free Beacon, 9/30/13]
• The National Review's Michael Barone said that the IPCC's models were a “failure” because, he claimed, “Global-warming models predicted [temperatures would increase over the last 15 years].” [National Review Online, 9/27/13]

Observed Warming Is Within The Range Of Previous IPCC Projections. According to the IPCC, even though past temperature projections were never intended to predict changes over short time spans, “the observations through 2012 generally fall within the projections made in all past assessments” (emphasis added):

Observed changes in global mean surface air temperature since 1950 (from three major databases, as anomalies relative to 1961-1990) are shown in Figure 1.4. As in the prior assessments, global climate models generally simulate global temperatures that compare well with observations over climate timescales (Section 9.4). Even though the projections from the models were never intended to be predictions over such a short time scale, the observations through 2012 generally fall within the projections made in all past assessments. The 1990-2012 data have been shown to be consistent with the FAR projections (IPCC, 1990), and not consistent with zero trend from 1990, even in the presence of substantial natural variability (Frame and Stone, 2013). The scenarios were designed to span a broad range of plausible futures, but are not aimed at predicting the most likely outcome.

[...]

The bars on the side for FAR, SAR and TAR represent the range of results for the scenarios at the end of the time period and are not error bars. By contrast to the previous reports the AR4 gave an assessment of the individual scenarios with a mean estimate (cross-bar; ensemble mean of the CMIP3 simulations) and a likely range (full bar; -40% to +60% of the mean estimate) (Meehl et al., 2007). In summary, the trend in globally-averaged surface temperatures falls within the range of the previous IPCC projections. During the last decade the trend in the observations is smaller than the mean of the projections of AR4 (see Section 9.4.1, Box 9.2 for a detailed assessment of the hiatus in global mean surface warming in the last 15 years).

[IPCC, 9/27/13]   

Warming Over Last 50 Years Almost Exactly As Estimated. The 2007 IPCC report actually said was that the rate of warming since 1951 was estimated to be about 0.13°C (0.23°F) per decade in the past 50 years. The new report said observations almost exactly bear that estimate out -- we have been warming at 0.12°C (0.22°F) per decade since 1951. The Mail on Sunday misreported a line from a different section of the study. [Carbon Brief, 9/16/13]

FACT: Fossil-Fuel Backed Group's Anti-IPCC Report Is Not Scientifically Rigorous.

MYTH: The NIPCC “Counters” The IPCC Report

• Fox News reporter Doug McKelway cited a report from the “Non-governmental International Panel on Climate Change” (NIPCC), published by the Heartland Institute, conflating it with the IPCC's forthcoming findings and concluding that “evidence of global warming is coming under increased scrutiny and increased doubt.” [Fox News, Happening Now, 9/18/13 via Media Matters]
• A Washington Times op-ed lamented that “Until recently, countering the International Panel on Climate Change reports with the views of climate scientists who do not support the scare has been exceptionally difficult,” but that the problem has been “solved” by reports from the NIPCC. It went on to quote a NIPCC contributor who compared his group favorably to the IPCC, saying “the authors and contributors to the NIPCC publications represent independent and often senior scientists who are beholden to no one, and have no political agenda to pursue. NIPCC presents the science as it is, not as it can be spun.” [Washington Times, 9/16/13]
• In a column praising the NIPCC at the expense of the IPCC, Paul Driessen characterized the latter “versus” the former as “facts versus gloom-and-doom assertions.”  [Townhall.com, 9/19/13]
• The Washington Free Beacon suggested that the NIPCC comes from a "[p]urely scientific perspective" without noting any critiques of its process. [Free Beacon, 9/27/13]

IPCC Reports Authored By Hundreds Of Volunteer Scientists, Exhaustively Reviewed. Mother Jones explained:

More than 800 climate scientists serve as authors and review editors in the three working groups. They come from 85 countries, with 301 of them from developing countries. These scientists call on hundreds more scientists for assistance. Together, they diligently mull reams of peer-reviewed climate science.

The results of this collaboration are draft reports that are debated, revised, and refined. For a sense of the exhaustiveness of the reviews, consider this: Working Group I has held 12 meetings in countries all over the world since 2010. It received 21,400 comments from 659 experts on its first draft, and then 31,422 more comments from 800 scientists and 26 governments on its second draft. [Mother Jones, 9/26/13]

NIPCC Authored By A Few “Skeptics,” Does Not Undergo Rigorous Review. Climate Science Watch noted that the NIPCC “does not follow the same rigorous scientific evaluation process as the IPCC,” echoing what two climate scientists told Media Matters. Kevin Trenberth of the National Center for Atmospheric Research stated that the NIPCC is “not open for review at any point”:

The NIPCC has no standing whatsoever. It is not a reviewed document, it is not open for review at any point and it contains demonstrable garbage and falsehoods. In contrast the IPCC process is rigorous, open and there are 2 major reviews. This is irresponsible journalism.

Princeton University professor Michael Oppenheimer added that citing the IPCC and NIPCC in the “same breath” can be misleading:

Media who cite both IPCC and NIPCC in the same breath (or in close proximity) are clearly either uninformed or attempting to confuse the public, unless of course, they are attempting to clear up any confusion about the two organizations by making clear that NIPCC does not represent the expert consensus on climate change. If NIPCC is ever cited, it should be within the latter context.

[Climate Science Watch, 9/9/13] [Media Matters, 9/18/13]

NIPCC Backed By Fossil-Fuel-Supported Heartland Institute. The NIPCC is published by the Heartland Institute and is funded by it and two other advocacy groups. Heartland has received backing from some corporations with a financial interest in confusing the public on climate science, and received over a quarter of its budget between 2002 and 2011 from Donors Trust, a group that bankrolls climate denial campaigns and has been called “the dark money ATM of the conservative movement.” Heartland's president has acknowledged that “the main motivation, frankly, for the Heartland Institute being involved in this [climate change] debate” is to prevent the U.S. government from adopting policies that favor renewable energy, which he claims would cause an “economic disaster for the country.” This involvement has taken the form of a billboard campaign associating “belief” in global warming with the Unabomber, among other things. [Media Matters, 9/18/13] [Media Matters, 11/28/12] [Media Matters, 2/28/13] [Media Matters, 7/7/11] [Media Matters, 5/4/12]

FACT: Many Experts See IPCC As Conservative In Its Approach

MYTH: The IPCC Is “Alarmist”

• A Washington Times op-ed claimed the IPCC “has become one of the world's strongest advocates of climate alarmism.” [Washington Times, 9/16/13]
• The Heartland Institute's James Taylor wrote in Forbes that­ the IPCC's “goal” is “to scare people into implementing the energy restrictions and wealth redistribution prescribed as a cure for the mythical global warming crisis.” [Forbes, 9/26/13]­
• In a later column, James Taylor compared a report backed by the Heartland Institute favorably to that of the IPCC, under the headline “Objective Science Unm­asks Global Warming Alarmists As The True Science 'Deniers.'” [Forbes, 9/20/13]
• A Washington Times op-ed claimed that IPCC authors “devised ways to cover up the 'bad' news” about the alleged end of global warming in order to produce a “scary report.” [Washington Times, 9/30/13] 

NY Times: IPCC Has “Ben[t] Over Backward To Be Scientifically Conservative.” The New York Times observed that, as evidenced by two examples involving sea level rise and climate sensitivity measures, the IPCC has sometimes shown to be “bending over backward to be scientifically conservative”:

Climate change skeptics often disparage these periodic reports from the United Nations, claiming that the panel writing them routinely stretches the boundaries of scientific evidence to make the problem look as dire as possible. So it is interesting to see that in these two important cases, the panel seems to be bending over backward to be scientifically conservative. [The New York Times, 9/10/13]

Scientists: IPCC Authors Made Cautious Choices. Scientists not involved in the IPCC process told The New York Times that the report's authors “made a series of cautious choices in their assessment of the scientific evidence”:

Climate scientists not involved in writing the new report said that the authors had made a series of cautious choices in their assessment of the scientific evidence.

Regarding sea level rise, for instance, they gave the first firm estimates ever contained in an intergovernmental panel report, declaring that if emissions continue at a rapid pace, the rise by the end of the 21st century could be as much as three feet. They threw out a string of published papers suggesting a worst-case rise closer to five feet.

Similarly, the authors went out of their way to include a recent batch of papers suggesting the earth might be somewhat less sensitive to carbon dioxide emissions than previously thought, even though serious questions have been raised about the validity of those estimates.

The new report lowered the bottom end of the range of potential warming that could be expected to occur over the long term if the carbon dioxide level in the atmosphere were to double, reversing a decision the panel made in the last report and restoring a scientific consensus that had prevailed from 1979 to 2007. Six years ago, that range was reported as 3.6 to 8.1 degrees Fahrenheit; the new range is 2.7 to 8.1 degrees. [The New York Times, 9/28/13]

IPCC Reviewer: Message “More Conservative” Than In Last Report. A chief scientist at the Netherlands Environmental Assessment Agency who reviewed the latest IPCC report told the BBC that the fifth assessment would be more “cautious” than the fourth:

There is a feeling among many scientists involved with the process that this report will be more complicated and cautious than in 2007.

[...]

“Overall, the message is, in that sense more conservative I expect, for this IPCC report compared to previous ones,” said Prof Petersen. “The language has become more complicated to understand, but it is more precise. [BBC News, 9/23/13]

Research Suggests IPCC May Be “Opposite” Of Alarmist. Skeptical Science noted that research has shown that the IPCC is actually more likely to underestimate effects of climate change:

[T]he evidence suggests that changes in climate are occurring faster, and with more intensity, than the IPCC have predicted. It is not credible to suggest the reports were biased in favour of the theory of anthropogenic global warming when the evidence demonstrates the IPCC were, in fact, so cautious.

In fact, there is evidence however to suggest that the exact opposite is actually the case, both in terms of the scientific evidence itself (see below) and the way the work of the IPCC is reported. A recent study (Freudenburg 2010) investigated what it calls 'the Asymmetry of Scientific Challenge', the phenomenon in which reports on science fail to evaluate all outcomes, favoring certain probabilities while ignoring others. They found that "...new scientific findings were more than twenty times as likely to support the ASC perspective [that disruption through AGW may be far worse than the IPCC has suggested] than the usual framing of the issue in the U.S. mass media".

Claims that the IPCC is alarmist are not supported by evidence, and there are clear indications that the opposite may be the case. [Skeptical Science, 8/1/13]

LiveScience: IPCC's Consensus-Seeking Can Lead To Underestimating Climate Impacts. LiveScience pointed out that the consensus-seeking nature of the IPCC makes it more likely to underestimate climate change impacts:

Since the IPCC's conclusions require consensus among the panel members, the organization's reports tend to feature fairly conservative estimates, with a tendency to underestimate rather than overestimate the potential impacts of climate change. [LiveScience, 9/18/13]

FACT: The IPCC Process Is Inclusive

MYTH: IPCC Authors & Reviewers Are Biased And Shut Out “Skeptics”

• A Wall Street Journal op-ed by a photographer and blogger Donna Laframboise in advance of the 2013 IPCC report attacked past editions for featuring authors and reviewers with alleged conflicts of interest because they had written reports or were employed by environmental groups. [Wall Street Journal, 9/25/13]
• In a column for Forbes hyping the newest NIPCC report, the Heartland Institute's James Taylor wrote that “the United Nations IPCC piles on laughably biased authors and truly sad incompetence,” citing the work of Laframboise. [Forbes, 9/20/13]
• A Washington Times op-ed lamented that “eco-activists” among other IPCC authors were “editing the science to reflect the politics.” [Washington Times, 9/30/13]

Scientist: “Climate 'Sceptics' Can And Do Participate, Some As Authors.” Climate scientist Kevin Trenberth explained that “Climate 'sceptics' can and do participate” in the IPCC process:

“Two major reviews are carried out in producing the report. The first is by experts and the second includes governments. Climate ”sceptics" can and do participate, some as authors. All comments are responded to in writing and result in many changes in the report. The process is overseen by two or more review editors for each chapter."

Climate Science Watch explained further that “The IPCC seeks input from as broad a range of scientists as possible, including those with industry ties”:

The IPCC seeks input from as broad a range of scientists as possible, including those with industry ties. Notable climate skeptics like Roger Pielke Jr. and Richard Lindzen have contributed to past reports, and Richard Tol and Hans von Storch, two prominent skeptics, participated in the current review. In addition, the IPCC has included experts from some of the largest companies in the fossil fuel industry, like ExxonMobil, Chevron, Shell, and BP.

[The Conversation, 9/28/13] [Climate Science Watch, 9/25/13]

IPCC Has Incorporated Conflict Of Interest Policy. One of the new IPCC guidelines taken on after a 2010 review of the panel's structure and process was a conflict of interest policy covering “all individuals directly involved in the preparation of IPCC reports,” including authors and review editors. [Media Matters, 9/25/13]