Tag Archives: climate science

The 97% consensus of climate scientists is only 47%

Summary: In February 2014 I examined surveys of climate scientists and found (as had others) that they showed broad agreement with the IPCC’s headline statement about warming since 1950. However time brings new research, such as a major survey that digs deeper and finds that only a minority of climate scientists agree with the full keynote statement of AR5 — the most recent IPCC report. That’s important news.

In March – April 2012 the PBL Netherlands Climate Assessment Agency, with several other scientists, conducted a survey of approximately 6,550 scientists studying climate change. It was published as “Scientists’ Views about Attribution of Global Warming” by Bart Verheggen et al in the 19 Aug 2014 issue of Environmental Science and Technology (peer-reviewed). In April 2015 they published a more detailed report (used in this post).

This survey covered many of the frontiers of climate science. This post examines one the questions about the keynote statement of the IPCC’s most recent work — Assessment Report 5 (AR5)…

“It is extremely likely {95%+ certainty} that more than half of the observed increase in global average surface temperature from 1951 to 2010 was caused by the anthropogenic increase in greenhouse gas concentrations and other anthropogenic forcings together. ”

— From the Summary for Policymakers of the IPCC’s AR5 Working Group I.

The PBL survey is the first I’ve seen to test agreement with both facets of that statement. First, how much of the global surface warming is caused by anthropogenic (human-caused) emissions of greenhouse gases? (Note AR5 referred to all factors; see “Details” below). Only 1,222 of 1,868 (64% of respondents) agreed with AR5 that the answer was over 50%. If we exclude the 164 (8.8%) “I don’t know” respondents, 72% agree with the IPCC. So far, so good.

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Testing Skeptical Science: is Roger Pielke Sr. a climate misinformer?

Summary: A post last week examined a darling of the Right, Zero Hedge. This post takes an equally harsh look at a darling of the Left, Skeptical Science. Both show how our stronger loyalty to tribe than truth encourages our information providers to feed us a mix of fact and politically appealing misinformation, shaping our beliefs and maintaining internal cohesion of the tribe (and our distrust of the “others”). We’ll remain gullible and easily led until we learn skepticism and demand more accuracy from those we trust.  {1st of 2 posts today.}

“Truth is strong enough to overcome all human sophistries.”
Timarchum by Aeschines (389–314 BC).

The Truth is Out There

Smearing scientists is a staple on both sides of the climate wars — the debate about the public policy implications of climate change. Such smears not only overflow the comment sections of popular websites, they’re often seen in the writings of major players on the public stage.

For example, see the 40 “climate misinformers” listed on John Cook’s Skeptical Science. It’s one of the climate-focused websites most widely cited on the Left, known for its flamboyant claims.  This post examines the first of 4 SkS page about eminent climate scientist Roger Pielke Sr.

Before examining the details of SkS’s content, note the vast amount of work that went into creating it. The 4 pages about Pielke Sr. are one of 40 about “climate misinformers” — which is one of 10 “resources”, which are just one part of the SkS website (which has aps for iPhone, Android, and Nokia). This shows a major difference between the websites of climate “warriors” and “skeptics”. Despite claims that the skeptics have vast funds from evil oil, their websites are a ramshackle pile of contributions from volunteers (however skilled). Several the climate warriors have professional-quality websites.

About a misinformer

What was are the myths of Roger Pielke Sr.? How do SkS’ claims look today? The SkS page (it’s undated) gives ten quotes which they call “myths”. Not one of their rebuttals looks correct. A lot of the SkS content is like that, which is why people so often report their critical comments get deleted (no Smackdowns page there). I’ve slightly expanded some of Pielke’s quotes, and made small edits for clarity (e.g., numbering the myths).

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Is our certain fate a coal-burning climate apocalypse? No!

As we approach November’s United Nations Climate Change Conference in Paris climate activists will warn of dismal futures, while others assure us that we need take no action. The IPCC’s Fifth Assessment Report 5 (AR5) provides a context for evaluation of these claims, from the horrific to the panglossian. This looks at the dark side of the range, scenarios possible but perhaps unlikely. {Revised July 20.}

World burning

In AR5 four Representative Concentration Pathways (RCPs) describe scenarios for future emissions, concentrations, and land-use, ending with radiative forcing levels of 2.6, 4.5, 6.0, and 8.5 W/m2 by 2100. Strong mitigation policies result in a low forcing level (RCP2.6). Two medium stabilization scenarios lead to intermediate outcomes: (RCP4.5, RCP6.0).

IPCC's AR5: 4 RCPs

RCP8.5 gets the most attention. It assumes the most population growth (a doubling of Earth’s population to 12 billion), the lowest rate of technology development, slow GDP growth, a massive increase in world poverty, plus high energy use and emissions. (For more about these RCPs see van Vuuren, Detlef P. et al 2011. “The representative concentration pathways: an overview”, Climatic Change 109: 1-2, pp 5-31. Source of these 2 graphics.)

People — from scientists to journalists — often describe RCP8.5 as the baseline scenario (“business as usual”), a future without policy action, resulting in severe climate impacts amidst a nightmarish world — but that’s an inaccurate description. Including such a scenario in AR5 would have been useful.

RCP8.5 shows the result of some extreme trends with little or no mitigation efforts. While conservative planning requires considering such extreme outcomes, journalists seldom discuss its assumptions or likelihood.

RP8.5 assumes population growth at the high end of the current UN probabilistic forecasts: 80% odds of between 9.6 and 12.3 billion people by 2100 (Gerland, P. et al, Science 10 Oct 2014). Most of this growth occurs in Africa, which in turn assumes that Africa can support that many people.

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A leading scientist warns about the climate: “The time for debate has ended. Action is urgently needed.”

Summary: The science establishment is betting its credibility, going all in on extreme climate in preparation for November’s United Nations Climate Change Conference in Paris.  The pretense of professional objectivity has been abandoned. The role of science in our society and the political Left — allies in this project — might depend on the weather of the next few years. Have they weighed the stakes vs. the risks?  {2nd of 2 posts today.}

A Burning World

Today’s astounding example of science at work is this editorial by Marcia McNutt — editor-in-Chief of Science and next President of the National Academy of Sciences — in the July 3 issue of Science: “The beyond-two-degree inferno“. Please read it in full, for you’ll see many more such statements this year. I’ll cite a few of its strange elements.

The coming inferno

“Let’s act now, to save the next generations from the consequences of the beyond-two-degree inferno.”

The title is shocking. Describing the effects of rising CO2 as apocalyptic is a defining trait of climate alarmists, outside the climate science mainstream since there is little support in the IPCC’s Working Group I reports for such dire forecasts.

There is little basis for describing a rise of 2 degrees above temperatures at the preindustrial moment (temperatures fluctuated before industrialization). For details see Samuel Randalls (University College) “History of the 2°C climate target” (WIRES Climate Change, July/Aug 2010). It might not inspire your confidence in the utility of 2°C as a red line.

Large increases in surface temperatures are possible if climate sensitivity is at the high end of current estimates and we burn off almost all the world’s fossil fuel deposits (especially coal) in the 21st century. However, the high end to estimates of the climate’s sensitivity to CO2 has been falling. The latter assumption seems even weaker. It’s only 2015 and the developed nations are already moving away from coal (North American coal consumption peaked in 2005, dropped 21% by 2012 — and continues to fall). Even China, the big coal growth story, intends large-scale replacement of coal-burning plants (forced by their horrific air pollution).

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Thomas Kuhn & Twitter tell us what we need to know about climate science

Summary: The history of science provides a vital perspective for anyone watching our time’s high stakes climate science debate. Look at Twitter and you will see the theories of the great Thomas Kuhn at work, helping us better understand the public policy debate.  {1st of 2 posts today.}

“First they ignore you. Then they ridicule you. And then they attack you and want to burn you. And then they build monuments to you.”
Speech by union leader Nicholas Klein (1918). This applies just as well to paradigm challenges in science.

Revolution

Contents

  1. The nature of science.
  2. The structure of real science.
  3. The structure of scientific revolutions.
  4. The state of climate science.
  5. What happens next?
  6. For More Information.

(1)  The nature of science

Much of the debate among laypeople about climate science (the only rational foundation for public policy debates about climate change) revolves around misunderstandings of how science works. There is the concept of “consensus” in science, politically useful but implies that the majority view indicates truth (as if vox populi, vox dei applies to science). There are more useful perspectives.

As scientists studying science have long known, it’s a social activity like any other. Our “wetware” evolved on the African plains and included nothing to produce intellectuals in the selfless pursuit of knowledge. Like war, western society has evolved it into a ferociously efficient mechanism that’s often not as pretty as shown in 1930’s films about heroic scientists challenging orthodoxy.

Science is a field with barriers to entry, training mechanisms to produce people who (usually) behave according to its canons, rules for their competition, and a hierarchy to control its workings and allocate its rewards. The winners climb to the top, basking in their community’s prestige (often unknown to the wider society), preferentially reward and advance their allies and protégés, withhold resources from their rivals, and bake their beliefs into the community’s thinking.

It’s the way of the world.

The study of science as a social activity tended to focus on its normative processes (i.e., how they should be). For example, Karl Popper said that scientists validate theories through attempts at falsification. A compelling theory, but study of actual scientists disproved it.

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Do models accurately predict climate change?

Summary: Climate models are important for several reasons. Large flows of tax dollars go to their construction and operation. Their predictions dominate the public policy debate about climate change (to the exclusion of other tools, such as predictability studies). In this post eminent climate scientist Roger Pielke Sr. explains that long-term model forecasts have shown little skill at forecasting. Post your questions in the comments; he’ll answer as time permits.  {1st of 2 posts today).

“I offer a toast to the future, the undiscovered country.”
— Klingon Chancellor Gorkon in Star Trek IV.

The undiscovered country from whose bourn no traveler returns, puzzles the will and makes us rather bear those ills we have than fly to others that we know not of? …And thus the native hue of resolution is sicklied o’er with the pale cast of thought, and enterprises of great pith and moment with this regard their currents turn awry, and lose the name of action.  {Hamlet}

Temperature change in NOAA's GFDL CM2.1 model.

Projected change in annual mean surface air temperature from the late 20th century (1971-2000 average) to the middle 21st century (2051-2060 average). This is based on a “middle of the road” estimate of future emissions ( IPCC SRES A1B). These results are from the GFDL CM2.1 model, but are consistent with a broad consensus of modeling results. From NOAA.

How accurately do the global climate models simulate the real climate?

Guest post by Roger A. Pielke Sr.

The climate models are useful as sensitivity experiments but using them to claim an ability to skillfully project climate, even on the global scale, in the coming decades has not been shown.

The new seminal Stephens et al paper provides a clear documentation of the level of model skill: “The albedo of Earth” in Reviews of Geophysics, March 2015. There is also a power point talk on this: “Is the Earth’s climatesystem constrained?” Among their conclusions is that …

“Climate models fail to reproduce the observed annual cycle in all components of the albedo with any realism, although they broadly capture the correct proportions of surface and atmospheric contributions to the TOA {top of atmosphere} albedo. A high model bias of albedo has also persisted since the time of CMIP3, mostly during the boreal summer season. Perhaps more importantly, models fail to produce the same degree of interannual constraint on the albedo variability nor do they reproduce the same degree of hemispheric symmetry.”

The technical term albedo “is the fraction of solar energy (shortwave radiation) reflected from the Earth back into space. It is a measure of the reflectivity of the earth’s surface. Ice, especially with snow on top of it, has a high albedo: most sunlight hitting the surface bounces back towards space” (From the Earth & Space Research website). CMIP3 is phase 3 of the Coupled Model Intercomparison Project (CMIP) of the World Climate Research Programme (WCRP). They collect the output of global climate models (i.e., coupled atmosphere-ocean general circulation models).

Stephens et al further bolsters the conclusions we summarized in the preface to Climate Vulnerability: Understanding and Addressing Threats to Essential Resources (5 volumes, 2013)…

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About the imminent spike in global warming

Summary: Our dysfunctional politics result largely from polarized views of Americans, both sides shaped by skillful and expensive propaganda. To break free we’ll need to learn their methods and develop far deeper skepticism. This is another in a series of posts looking at examples of our minds being molded by pros. It discusses the work of climate activists, but it’s vital to understand that both sides do this — because it works.  {2nd of 2 posts today.}

Global Warming

Yesterday’s post discussed the largely erroneous framing in an article about climate change by investment expert Barry Ritholtz at Bloomberg. How do intelligent, educated people become so convinced by the propaganda of climate activists, dismissing any who disagree with them as “deniers”?

We might find an answer by looking at the work of activists, such as Joe Romm (note that most climate activists are paid employees, unlike most of those on the Right). This post follows his chain of evidence in a typical article, showing how his bold conclusions rest on misrepresentations of the literature, and exaggerating the scope and certainty of specific papers.

The work by activists have large effects because liberals often read only activists, giving them a misunderstanding of climate science — exacerbated because activists seldom cite the work of institutions like the IPCC (designed to make the work of scientists understandable to laypeople).

Today’s example: “NOAA Study Confirms Global Warming Speed-Up Is Imminent” at ThinkProgress, 5 June 201 — Opening …

A major new study from NOAA finds more evidence that we may be witnessing the start of the long-awaited jump in global temperatures. As I reported in April, many recent studies have found that we are about to enter an era of even more rapid global warming. … The new study in Science from a team of NOAA scientists, “finds that the rate of global warming during the last 15 years has been as fast as or faster than that seen during the latter half of the 20th Century,” as NOAA explains.

… What happens when these various temporary factors stop? Karl explained: “Once these factors play out, and they may have already, global temperatures could rise more rapidly than what we have seen so far.” In other words, the long-awaited jump is global temperatures is likely imminent.

The cracks appear right at the start of this. Note the jump between Karl’s careful “may have already … could rise” and Romm’s “likely imminent”. Romm also omits the cautious language Karl gives in the NOAA’s well-written (as always) press releases (first one, second one) …

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