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- We've been through climate changes before
- Interactive mythbusting in Lane Cove
- Lindzen's Junk Science
- A Sunburnt Country
- Lindzen's London Illusions
- New research from last week 9/2012
- PMO Pest Control: Scientists
- 2012 SkS Weekly Digest #9
- Oceans Acidifying Faster Today Than in Past 300 Million Years
- Roy Spencer's Junk Science
- Warming to Ignite the Carbon Bomb
- Wall Street Journal 'Skeptics' Misrepresent the IPCC
- Nordhaus Sets the Record Straight - Climate Mitigation Saves Money
- The Certainty Monster vs. The Uncertainty Ewok
- The Independence of Global Warming on Residence Time of CO2
- Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
- New research from last week 8/2012
- Mythbusting with fewer explosions
- DenialGate - Highlighting Bob Carter's Selective Science
- 2012 SkS Weekly Digest #8
- Climate change models underestimate future temperature variability; food security at risk
- German translation of The Debunking Handbook
- Monckton Misrepresents Reality (Part 3)
- Radiative Balance, Feedback, and Runaway Warming
- Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
- Scafetta's Widget Problems
- Monckton Misrepresents Specific Situations (Part 2)
- Uncertainty Is Not the Basis for Investment
- New research from last week 7/2012
- Monckton Misrepresents Scientists' Own Work (Part 1)
Explaining climate change science & rebutting global warming misinformation
Scientific skepticism is healthy. Scientists should always challenge themselves to improve their understanding. Yet this isn't what happens with climate change denial. Skeptics vigorously criticise any evidence that supports man-made global warming and yet embrace any argument, op-ed, blog or study that refutes global warming. This website gets skeptical about global warming skepticism. Do their arguments have any scientific basis? What does the peer reviewed scientific literature say?
We've been through climate changes before
Posted on 9 March 2012 by Sarah
This is the basic rebuttal to 'Humans survived past climate changes'
Humans have been through climate changes before- but mostly cold ones and mostly in our far distant past.
"Yes, our climates change. They've been changing ever since the Earth was formed." Rick Perry
Previous major global climate changes were glacial cycles that happened long before human civilization developed.
The human species evolved during the last 2.5 million years. Our far distant ancestors survived through multiple gradual cycles of cold ice ages, but did not experience any previous "hot ages."
We homo sapiens in our current form appeared only about 200,000 years ago. So our species has survived two ice ages. In each ice age global temperatures were colder by 4 °C. The warmest period ever experienced by early humans was about 1 °C warmer (global average) than today. That period occured between the two most recent ice ages, 120,000 years ago (Eemian). Over the next 100,000 years temperatures gradually decreased into a new ice age. During that colder period humans began to expand out of Africa and across the globe. Ever since the Eemian much cooler temperatures have been the norm.
Image by John Garrett.
Interactive mythbusting in Lane Cove
Posted on 9 March 2012 by John Cook
Last week, I was part of an interactive mythbusting evening at Lane Cove, Sydney. The evening was the brain child of Rebecca Jones from Sustain Me Consulting who organised a series of interactive sustainability workshops with Lane Cove Council. The idea of these workshops is to inspire local residents and businesses to take practical actions on environmental issues. You can check out some of the other workshops on her Facebook page, including a cook-off with Masterchef contestant Billy Law using leftovers to raise awareness about food waste.
Rebecca's approach is organising interactive workshops where the audience actively participate and contribute to the evening. So her suggestion was rather than give a prepared talk, we let the audience decide the agenda for the evening, decide what skeptic arguments they find most convincing and then it would be up to me to debunk any myths that arise. I have to admit that removing the security blanket of a prepared talk was a little unsettling - public speaking is hard enough as it is! But the idea of a purely interactive mythbusting evening did sound pretty cool albeit unpredictable.
As preparation, I put together a powerpoint of slides addressing the most popular climate myths (I will make this powerpoint avaiable online down the track but would like to tinker with it some more first). I had the list of myths on my iPad, each with it's own slide number, and when needed, I'd punch the number into Powerpoint and jump to the appropriate slide. Sounds good in theory, right?
Lindzen's Junk Science
Posted on 8 March 2012 by dana1981
This is a re-post from Gavin Schmidt at RealClimate regarding another Lindzen misrepresentation in the seminar discussed in Lindzen's London Illusions. As noted by Skeptical Science reader WheelsOC, the graphic in question used by Lindzen in his London presentation appears to have been created by Howard Hayden and posted on Junk Science. This suggests that the error discussed by Schmidt was actually made by Hayden and then uncritically reproduced by Lindzen (who also did not provide a reference citation for the faulty graphic in his presentation).
Richard Lindzen is a very special character in the climate debate – very smart, high profile, and with a solid background in atmospheric dynamics. He has, in times past, raised interesting critiques of the mainstream science. None of them, however, have stood the test of time – but exploring the issues was useful. More recently though, and especially in his more public outings, he spends most of his time misrepresenting the science and is a master at leading people to believe things that are not true without him ever saying them explicitly.
However, in his latest excursion at a briefing at the House of Commons in the UK, among the standard Lindzen arguments was the following slide (which appears to be a new addition):
What Lindzen is purporting to do is to compare the NASA GISS temperature product from 2012 to the version in 2008 (i.e. the y-axis is the supposedly the difference between what GISS estimated the anomaly to be in 2012 relative to 2008). A rising trend would imply that temperatures in more recent years had been preferentially enhanced in the 2012 product. The claim being made is that NASA GISS has ‘manipulated’ (in a bad way) the data in order to produce an increasing trend of global mean temperature anomalies (to the tune of 0.14ºC/Century compared to the overall trend of 0.8ºC/Century) between the 2008 and 2012 versions of the data, which are apparently shown subtracted from each other in Lindzen’s figure. Apparently, this got ‘a big laugh’ at his presentation.
However, this is not in the least bit true: the data are not what he claims, the interpretation is wrong, and the insinuations are spurious.
A Sunburnt Country
Posted on 7 March 2012 by Glenn Tamblyn
I Love a Sunburnt Country
Sometimes we get important insights from the most unexpected of places. Poets & Insurance Companies. Not what we might always connect together. But you never know what they might be able to offer...
In my home country of Australia, one of the iconic poems in our history is often referred to simply as ‘I Love a Sunburnt Country’. Written by Dorothea MacKellar it was originally published in the London Spectator in 1908 as ‘Core of My Heart’. Later she called it simply ‘My Country’. It is often called ‘I Love a Sunburnt Country’ by Australians because, like most of us, we reduce the world around us to simple images and ideas. We loose the vivid wonderful complexity but we gain ease of comprehension. So too it is with Dorothea’s poem. We remember the bits that grab our soul rather than the whole poem.
Few Australians would have ever heard the first stanza of the poem. But lines from the second stanza can still make the hairs on the back of our neck stand up. Young Dorothea wrote this in England where she was travelling with her father and feeling quite homesick.
The love of field and coppice,
Of green and shaded lanes.
Of ordered woods and gardens
Is running in your veins,
Strong love of grey-blue distance
Brown streams and soft dim skies
I know but cannot share it,
My love is otherwise.
I love a sunburnt country,
A land of sweeping plains,
Of ragged mountain ranges,
Of droughts and flooding rains.
I love her far horizons,
I love her jewel-sea,
Her beauty and her terror -
The wide brown land for me!
Lindzen's London Illusions
Posted on 7 March 2012 by dana1981
On 22 February 2012, Richard Lindzen gave a talk to invited guests in a rented room in the Palace of Westminster. Note that contrary to some reports about the seminar, it was not presented to UK Parliament. Any member of the UK legislature can rent one of the many Palace of Westminster rooms for private purposes; that is what happened in this instance.
Lindzen's presentation, the slides of which can be viewed here and video can be seen here, appeared very similar to presentations given by Christopher Monckton. In fact, Lindzen's talk contained many of the same climate myths we recently debunked from Monckton, which frankly does not reflect well on Lindzen. The slides and presentation are almost identical to Lindzen's testimony to the US House Subcommittee on Science and Technology hearing in November 2010, which in turn was almost identical to a presentation he gave at a Heartland Institute conference 6 months earlier. In fact, Lindzen did not even update some of his graphs with data beyond mid-2010 for his UK presentation.
Lindzen's presentation contained so many misrepresentations that it would be too time consuming to address them all; however, we will address most of them here, including the base on which Lindzen built his house of misinformation cards.
New research from last week 9/2012
Posted on 6 March 2012 by Ari Jokimäki
This week's scientists are from Estonia, Finland, France, Germany, India, Italy, Netherlands, Portugal, Spain, Switzerland, United Kingdom, and United States. It seems that we have lot of European studies this week. Oh, the studies themselves? Well, they are amazingly interesting as usual. They have studied cold spells, aerosols, clouds, maximum temperatures, water vapor, meteorological measurements, lake sediments, winter precipitation, trees, and even crop prices. And you should have seen the studies that got away!
PMO Pest Control: Scientists
Posted on 6 March 2012 by Robert Way, Albatross, Andy S, climatesight
All four authors of this article are Canadian scientists and/or science students.
Recently on the comedic Canadian television program The Mercer Report, a satirical look is taken at the state of science in Canada since the Harper GovernmentTM came into power in 2006.
The video is below:
PMO = Office of the Prime Minister (Stephen Harper)
Although depicted with humor in this video the current state of science in Canada is no laughing matter. For example:
2012 SkS Weekly Digest #9
Posted on 5 March 2012 by John Hartz
SkS Highlights
Based on the number of comments posted to date, Keith Pickering's Wall Street Journal 'Skeptics' Misrepresent the IPCC and Tom Curtis' Greenhouse Effect Basics: Warm Earth, Cold Atmosphere were the two most popular articles posted this past week. Dana's The Certainty Monster vs. The Uncertainty Ewok and Dikran Marsupial's The Independence of Global Warming on Residence Time of CO2 also generated a goodly number of comments.
Toon of the Week
Oceans Acidifying Faster Today Than in Past 300 Million Years
Posted on 5 March 2012 by John Hartz
This is a reprint of a news release posted by the National Science Foundation on March 1, 2012.
Few parallels for today's rapid ocean changes in geologic record
The oceans may be acidifying faster today than they did in the last 300 million years, according to scientists publishing a paper this week in the journal Science.
"What we're doing today really stands out in the geologic record," says lead author Bärbel Hönisch, a paleoceanographer at Columbia University's Lamont-Doherty Earth Observatory.
"We know that life during past ocean acidification events was not wiped out--new species evolved to replace those that died off. But if industrial carbon emissions continue at the current pace, we may lose organisms we care about--coral reefs, oysters, salmon."
The oceans act like a sponge to draw down excess carbon dioxide from the air.
The gas reacts with seawater to form carbonic acid, which over time is neutralized by fossil carbonate shells on the seafloor.
If too much carbon dioxide enters the ocean too quickly, it can deplete the carbonate ions that corals, mollusks and some plankton need for reef and shell-building.
Roy Spencer's Junk Science
Posted on 5 March 2012 by bbickmore
This is a cross-post from Barry Bickmore's blog
Roy Spencer recently posted an article on his blog called “Ten Years After the Warming,” in which he argues that there’s no excuse for a decade without much warming, because the radiative forcing is supposedly higher than it’s ever been. Steve Milloy has also reposted the article on his aptly titled blog, JunkScience.com. (In case you don’t remember, Steve Milloy is a Fox News commentator who goes about labeling as “junk science” any environmental issues that might precipitate some government regulation. Yes, that includes links between second-hand smoke and cancer.) Spencer’s main point is this:
"You cannot simply say a lack of warming in 10 years is not that unusual, and that there have been previous 10-year periods without warming, too. No, we are supposedly in uncharted territory with a maximum in radiative forcing of the climate system. One cannot compare on an equal basis the last 10 years with any previous decades without warming."
This is the same Roy Spencer who is constantly claiming that he can explain most of the warming trend over the last 100 years by appealing to various modes of natural variation in the climate, e.g., the Pacific Decadal Oscillation and the El Niño Southern Oscillation. These climate oscillations depend on complicated stuff like deep ocean currents that are hard to predict, given that we don’t have that many observations of what the state of the system is like at any given time. (In other words, it’s expensive and hard to measure deep ocean temperatures and currents, so we don’t have that many observations.) Since these kinds of things are hard to predict exactly with a model, climatologists usually talk about long-term trends caused by external “forcing” (by things like CO2 emissions and variations in solar output), overprinted by random “natural variation”. The main difference between Roy Spencer and the rest of the climatologists is that he thinks that natural variation is important over much longer time periods, whereas the others generally think it’s mainly important over about a decade or less. For example, he complained in his book, , The Great Global Warming Blunder,
Warming to Ignite the Carbon Bomb
Posted on 4 March 2012 by Stephen Leahy
NOTE: This is a reprint of an article by Stephen Leahy originally appearing in IPS News
- Rising temperatures are drying out northern forests and peatlands, producing bigger and more intense fires. And this will only get much worse as the planet heats up from the use of ever larger amounts of fossil fuels, scientists warned last week at the end of a major science meeting in Vancouver.
“In a warmer world, there will be more fire. That’s a virtual certainty,” said Mike Flannigan, a forest researcher at the University of Alberta, Canada.
“I’d say a doubling or even tripling of fire events is a conservative estimate,” Flannigan told IPS.
Worldwide, fires burn an estimated 350 to 450 million ha of forest and grasslands every year - an area larger than India. Credit: Carl Osbourn/CC BY 2.0
Wall Street Journal 'Skeptics' Misrepresent the IPCC
Posted on 3 March 2012 by keithpickering
A recent comment thread at RealClimate contains some loose talk about Skeptical Science (SkS), including one commenter's complaint that SkS has not (or not adequately) discussed the climate projections of the IPCC's 1990 First Assesment Report (FAR). Although we have posted about the FAR in the past, this is a good time to take another look.
Figure 1 shows the IPCC's 1990 projections from FAR, figure 6.11, page 190 (the original pdf is a scanned image that is slightly skewed; I have corrected that here).
Figure 1: IPCC FAR Figure 6.11, surface temperature projections
Nordhaus Sets the Record Straight - Climate Mitigation Saves Money
Posted on 2 March 2012 by dana1981
Yale's William Nordhaus is one of the foremost experts on climate economics. His research has frequently been misrepresented by climate "skeptics" to argue that CO2 limits will harm the economy. For example, Christopher Monckton cited a climate economics review by Richard Tol (which in turn heavily cited work by Nordhaus) in claiming:
"...the overwhelming majority of economic studies on the subject (which are summarized in my paper) find the cost of climate action greatly exceeds the cost of inaction..."
As we demonstrated in our response, Monckton completely misrepresented the work of Tol (and Nordhaus, by extension), and thus his claim is 100% wrong. The reality is that the overwhelming majority of economic studies on climate find the cost of climate inaction greatly exceeds the cost of action (Figure 1). That's why there is a consensus amongst economists with climate expertise that we should reduce greenhouse gas emissions (Figure 2).
Figure 1: Approximate costs of climate action (green) and inaction (red) in 2100 and 2200. Sources: German Institute for Economic Research and Watkiss et al. 2005
Figure 2: New York University survey results of economists with climate expertise when asked under what circumstances the USA should reduce its emissions
Similarly, a recent letter published by the Wall Street Journal, signed by 16 climate "skeptics" (few of which have any climate or economics expertise, and many of which have received fossil fuel funding) misrepresented Nordhaus' research as supporting climate inaction from an economic standpoint. When Nordhaus objected to this misrepresentation of his work, Patrick Michaels doubled-down on the misrepresentation, claiming Nordhaus didn't understand his own research.
The Certainty Monster vs. The Uncertainty Ewok
Posted on 2 March 2012 by dana1981
In a recent post on her blog, climate scientist Judith Curry discussed relatively recent global surface temperature changes, and the causes of those changes. Curry put forth 3 "hypotheses" (one of which is actually a theory, not a hypothesis [see if you can pick out which]):
I. IPCC AGW hypothesis
II. Multi-decadal oscillations plus trend hypothesis
III: Climate shifts hypothesis
Note that in all three of these theories/hypotheses, there exists an underlying (human-caused) warming trend, and thus what Curry is really discussing is how to best explain the short-term noise in the climate system. However, Curry incorrectly states:
"Each of these three hypotheses provides a different interpretation of the 20th century attribution and has different implications for 21st century climate."
As noted above, the attribution of the observed global warming is not the question here. In each case, the long-term warming is attributed to the external radiative forcing, which has been dominated by human greenhouse gas emissions (Figure 1).
Figure 1: Percent contributions of various effects to the observed global surface warming over the past 50-65 years according to Tett et al. 2000 (T00, dark blue), Meehl et al. 2004 (M04, red), Stone et al. 2007 (S07, green), Lean and Rind 2008 (LR08, purple), Huber and Knutti 2011 (HK11, light blue), and Gillett et al. 2012 (G12, orange).
The Independence of Global Warming on Residence Time of CO2
Posted on 1 March 2012 by Dikran Marsupial
A hearty congratulations from the SkS team to our own Dikran Marsupial for getting a response to Essenhigh (2009) published.
A climate myth that crops up far more often than it should is that the rise in atmospheric CO2 since the industrial revolution is not caused by anthropogenic carbon emissions, but is instead a natural phenomenon. This has been addressed repeatedly on SkS, for example see CO2 increase is natural, not human-caused. An example of this argument is found in the paper "Potential Dependence of Global Warming on the Residence Time (RT) in the Atmosphere of Anthropogenically Sourced Carbon Dioxide" by Prof. Robert Essenhigh that appeared in the journal Energy and Fuels in 2009. The argument is easily refuted by the observation that the rate at which atmospheric CO2 levels are rising is less than the rate at which we are releasing CO2 into the atmosphere from fossil fuel use, which implies that the natural environment must be a net carbon sink, taking in more carbon each year than it emits.
More formally, let Ea represent annual carbon emissions from anthropogenic sources (fossil fuel use and land use change), En represent the carbon emissions from all natural sources (the oceans, soil respiration, volcanos etc.) and Un represent the uptake of carbon by all natural carbon sinks (oceans, photosynthesis, etc.), Ua would be the uptake of carbon due to anthropogenic activities, but this is essentially zero, so we can safely exclude it from the analysis. Then assuming that the carbon cycle obeys the principle of conservation of mass (any carbon emitted into the atmosphere that is not taken up by natural sinks remains in the atmosphere), the annual change in atmospheric CO2 is given by:
C' = Ea + En - Un
This can be rearranged to give an estimate of the difference between annual emissions from all natural sources and annual natural uptake by all natural sinks.
En - Un = C' - Ea
We have accurate, reliable data for the growth of atmospheric CO2 and for anthropogenic emissions (for details, see Cawley, 2011). Both of these are displayed below, along with an estimate of the net natural carbon flux En - Un. The fact that the net natural flux is negative clearly shows that natural uptake has exceeded natural emissions every year for the last fifty years at least, and hence has been opposing, rather than causing the observed rise in atmospheric CO2.
Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
Posted on 29 February 2012 by Tom Curtis
Heating and Heat Flow
Some physics, everyone knows. In our daily lives we encounter the effects of physics all the time, and as a result, we know what physics predicts in those circumstances at a gut level. We may not be able to put it into numbers. We may not be able to apply it in novel situations. But we know it all the same.
One example is as simple as putting on a blanket. We know that if we want warm something up, we can increase the supply of heat - or we can reduce the escape of heat. Either is effective. If you have a pot that is simmering and you want to bring it to the boil, you can turn the heat up, or you can put on the lid. If we put on the lid, the pot will go nicely from simmering to boiling, and we don't need to turn up the heat even slightly. Indeed, if we are not careful to turn down the heat, the pot may well boil over.
Likewise, if you have two identical motors running with an identical load and speed (Revolutions Per Minute), one with the water pump working and one without, we are all physicist enough to say that the second one will run hotter. It does not matter that the energy supplied as fuel is identical in both cases. The fact that heat escapes more easilly with water circulating through the radiator will keep the first cooler. The consequence is that stopping the the water from circulating will lead second motor to disaster.
Nor do we find people who doubt this. Suppose somebody told us their water pump was broken, but that the Second Law of Thermodynamics prohibited transfer of heat from a cooler place (the water) to a hotter place (the engine block), so they'ld be fine so long as they didn't rev any faster than normal, we'ld look at them in complete disbelief. Or we would if we were too polite to burst out laughing. And if they set out cross country confident in their belief, it doesn't matter what destination they claim they're heading for. Rather, as we all know, they're really heading for a breakdown!
New research from last week 8/2012
Posted on 28 February 2012 by Ari Jokimäki
You know those that claim global warming has stopped? Well, it seems that they are talking about boreal winter only.
You know the climate models that can't do anything right? Well, it seems that they should put tails on them.
You know that the global warming has happened before? Well, it seems that also mass extinctions have happened before.
We also have studies on Himalayan glaciers, Central America climate change rate, extreme weather in China, Russian 2010 heat wave, wind power density, Miocene climate optimum, Turkey corn, and climate sensitivity. Question of the week is: Do kangaroos in Australia affect the temperature trends?
Mythbusting with fewer explosions
Posted on 28 February 2012 by John Cook
A few articles about myth busting and the Debunking Handbook have been posted over the last 24 hours. This morning, ABC Environment published my article Mythbusting with fewer explosions. They gave the article the tag-line "Busting myths is less like an episode of Mythbusters and more like an Indiana Jones film" (which just goes to show how much better journalists are at succinctly summing up an article in a catchy, single line). I talk about the general principles of debunking myths but also about my myth busting evening tonight in Lane Cove, Sydney (there may still be spots left so click here to register). Here's an excerpt where I explore the idea that myth busting is not just a necessary evil but can be an opportunity for teachable moments:
It's not enough to merely remove the myth. When you debunk misinformation, you leave a gap in the person's understanding. That gap needs to be filled with an alternative explanation. This is a crucial element to a successful debunking - create a gap, fill the gap - that also presents an exciting opportunity.
In Chip and Dan Heath's book Made To Stick, the authors explore how communicators can arouse people's interest to create 'sticky ideas'. One approach is "Gap Theory", based on the fact that curiosity is stirred when we perceive a gap in our knowledge. We've all experienced this - who hasn't sat through a bad movie just to find out how it ends? I watched Lost for several seasons more than I should have for this very reason. To communicate in a compelling, engaging fashion, you need to highlight gaps in people's knowledge, provoke their curiosity then fill the gaps.
Sound familiar? The structure required to debunk a myth - create a gap, fill the gap - is also the key to compelling, engaging communication. Debunking myths doesn't need to be considered just a necessary evil. It's an opportunity to use the response to misinformation as a teachable moment.
DenialGate - Highlighting Bob Carter's Selective Science
Posted on 28 February 2012 by dana1981
Although we at Skeptical Science (SkS) do not condone the lamentable means through which Peter Gleick obtained the DenialGate documents from the Heartland Institute, the information is nevertheless out there. As we immediately noted, these documents should not distract us from the scientific evidence. While the behavior of Gleick and Heartland make for juicy tabloid fodder, they don't change scientific reality, and that reality is not influenced by political think tank politics, either. As Kate at ClimateSight put it,
"...on matters of science, there is a physical reality out there, so people can be wrong. Try arguing that your incorrect answer on a physics assignment deserves full marks, because it represents your personal opinion on the photoelectric effect. You probably won’t get very far."
In our first entry on the subject, we examined the key pseudo-scientific product of the Heartland Institute, the NIPCC report. In doing so we found that the Heartland climate "skeptics" are guilty of exactly what they wrongly accuse the IPCC and climate realists of doing: focusing only on a narrow subset of scientific literature which supports their climate position and ignoring the rest. In fact, the NIPCC report turns out to be little more than a regurgitation of a number of long-debunked climate myths, many of which are self-contradictory.
Here we will examine the scientific publications and arguments made by one of the NIPCC's lead authors on the Heartland Institute's payroll, Bob Carter, who unsurprisingly is guilty of many of the same inconsistencies and selective vision as the report he co-authored.
2012 SkS Weekly Digest #8
Posted on 27 February 2012 by John Hartz
SkS Highlights
Monckton's constant problems misreading - and consequently misrepresenting - the climate science literature is documented in detail in the three part post, Monckton Misrepresents Scientists' Own Work, collaboratively written by Dana, Alex C and Tom Curtis. As to be expected, this set of articles generated numerous comments. Uncertainty Is Not the Basis for Investment by JG also generated a lot of attention. Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas by Mark R may have set the SkS record for longest title a posted article.
Toon of the Week
THE ESCALATOR
(free to republish)
The Scientific Guide to
Global Warming Skepticism
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