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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?

Breaking News…The Earth Is Warming…Still!

Posted on 17 February 2012 by Glenn Tamblyn

In my under-graduate days, studying engineering some years ago (quite a few actually but the less said about that the better), one idea was drummed into us again and again. If you want to study any sort of system you absolutely need to define your ‘system boundaries’ correctly. What are the boundaries of the thing you are studying? Get this right and your analysis may be solid. Get it wrong and your analysis will be rubbish.

Bounding Around

So when we think about Global Warming we need to be really certain that our ‘system boundaries’ are right. So what is the theory of Global Warming, in a nutshell? And what does this tell us about where we need to set our boundaries. Put at its simplest, Global Warming says that more GH Gases will cause an imbalance between the amount of energy the Earth receives from the Sun, and the energy it looses to Space. More of the GH gases make it harder for the Earth to loose energy to space, so heat starts to build-up here. And this heat build up can lead to higher temperatures.

So what does this tell us about what needs to be inside our ‘system boundary’?

Our system boundary needs to include anywhere where this extra heat can accumulate! To understand Global Warming we need to look at all the places where heat can go and account for all of them.

And this is what the scientists have done. This graph, taken from the IPCC’s 2007 report shows the estimates of how much heat has been added to different parts of the environment – melting ice, warming the land, air and oceans between 1961-2003 and 1993 - 2003.

Heating since 1961



Video of Chuck Kutscher debunking climate skeptic arguments

Posted on 16 February 2012 by John Cook

The following is a video presentation Debunking Climate Skeptics by Chuck Kutscher from the National Renewable Energy Laboratory and chair of the 2012 World Renewable Energy Forum in Denver in May. The talk was presented at the Colorado State Capitol in a January 2011 workshop for members of the state legislature. 

Note - another cool presentation at the workshop was Key Evidence for Climate Change by climate scientist Caspar Amman. You can also download PowerPoint slides of all the presentations given at the workshop.



Tropical Thermostats and Global Warming

Posted on 16 February 2012 by Chris Colose

A recent post at Watts Up With That by Willis Eschenbach, and then embraced by Roger Pielke Sr., goes into detail concerning a purported "tropical thermostat" that sets an upper limit on the ocean temperature.  This thermostat could presumably help regulate the response to radiative forcing in a higher CO2 world, constraining ocean temperatures to be no greater than the threshold value.

The underlying hypothesis is actually not of WUWT-origin and has some roots that were discussed in the literature dating back a couple decades.  WUWT presents a histogram of observed ocean temperatures, which shows a sharp cut off at ~31 °C (diagram reproduced below).  The figure indicates that no measurements in the worlds oceans show temperatures much higher than that value.  Based on this data, WUWT (as well as several older scientific papers based on similar data) suggested this is a theoretical 'maximum ocean temperature' and is independent of solar or greenhouse forcing. Kleypas et al 2008, for example, based a study on corals on the premise that such data support a maximum ocean temperature.

Figure 1. A “histogram” shows how many data points fall in each of the 1°C intervals shown along the bottom axis. The maximum is in the interval 28°-29°C. Figure and Caption reproduced from WUWT article.



Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network

Posted on 15 February 2012 by dana1981

This is a combined re-post of two major exposé posts on DeSmogBlog (here and here) regarding internal Heartland Institute strategy and funding documents.

*UPDATE* DeSmogBlog now reports on a prepared statement from Heartland Institute regarding the leak:  

The Heartland Institute has confirmed in a prepared statement that it mistakenly emailed its board materials to an anonymous third party - confirming the source of the documents released here on the DeSmogBlog yesterday.

Heartland then goes on allege that one of the documents (the Climate Strategy) is a fake.

The DeSmogBlog has reviewed that Strategy document and compared its content to other material we have in hand. It addresses five elements:

The Increased Climate Project Fundraising material is reproduced in and confirmed by Heartland's own budget.

The "Global Warming Curriculum for K-12 Classrooms" is also a Heartland budget item and has been confirmed independently by the author, Dr. David Wojick.

The Funding for Parallel Organizations; Funding for Selected Individuals Outside Heartland are both reproduced and confirmed in the Heartland budget. And Anthony Watts has confirmed independently the payments in Expanded Climate Communications.

The DeSmogBlog has received no direct communications from the Heartland Institute identifying any misstatement of fact in the "Climate Strategy" document and is therefore leaving the material available to those who may judge their content and veracity based on these and other sources.

*SkS note: Heartland could easily prove the strategy document is a fake by releasing the email which they claim contained the released documents.



Heartland Insider Exposes Institute's Budget and Strategy

An anonymous donor calling him (or her)self "Heartland Insider" has released the Heartland Institute's budget, fundraising plan, its Climate Strategy for 2012 and sundry other documents (all attached) that prove all of the worst allegations that have been levelled against the organization.

It is clear from the documents that Heartland advocates against responsible climate mitigation and then uses that advocacy to raise money from oil companies and "other corporations whose interests are threatened by climate policies." Heartland particularly celebrates the funding that it receives from the fossil fuel fortune being the Charles G. Koch Foundation.

Heartland also continues to collect money from Philip Morris parent company Altria as well as from the tobacco giant Reynolds American, while maintaining ongoing advocacy against policies related to smoking and health.

Heartland's policy positions, strategies and budget distinguish it clear as a lobby firm that is misrepresenting itself as a "think tank" - it budgets $4.1 million of its $6.4 million in projected expenditures for Editorial, Government Relations, Communications, Fundraising, and Publications, and the only activity it plans that could vaguely be considered policy development is the writing of a curriculum package for use in confusing high schoolers about climate change.



Fritz Vahrenholt - Duped on Climate Change

Posted on 15 February 2012 by dana1981

German electric utility executive Fritz Vahrenholt is co-author (along with geologist Sebastian Lüning) of a book expressing "skepticism" regarding the human contribution to global warming, which predictably has been trumpeted by the usual climate denial enablers.  Why should we particularly care what Vahrenholt thinks about climate science?  That is something of a mystery - he has a PhD in chemistry and has worked in the energy sector for Shell Oil and wind turbine maker RePower.  Vahrenholt and Lüning both currently work for RWE Innogy, Germany's second-largest energy company (Vahrenholt as a manager, Lüning as a scientist in its oil and gas division).

Vahrenholt admits he has no expertise in climate science, but apparently his status as "Germany’s Top Environmentalist" (a title which Vahrenholt appears to have been awarded just recently by anti-climate think tanks and denialists) and his climate "skepticism" are sufficient for some people to take his climate claims seriously.

In an interview with Der Spiegel, Vahrenholt discusses why he chose to write a book rather than attempting to conduct and publish scientific research.

SPIEGEL: You make concrete statements on how much human activity contributes to climatic events and how much of a role natural factors play. Why don't you publish your prognoses in a professional journal?

Vahrenholt: Because I don't engage in my own climate research. Besides, I don't have a supercomputer in my basement.  For the most part, my co-author, geologist Sebastian Lüning, and I merely summarize what scientists have published in professional journals -- just as the IPCC does.

However, as we will soon see, the difference between Vahrenholt and the IPCC is that the latter accurately summarizes the body scientific literature, while the former misrepresents his sources and only listens to a few select "skeptic" scientists.



New research from last week 6/2012

Posted on 14 February 2012 by Ari Jokimäki

Michael Mann has been a busy beaver this week - not only is there the book thing he's doing, but he also managed to get his name on two of the papers here. So, Dr. Mann, with my unanimous decision, you are the scientist of the week!

So the climate warms and Italian trees get their temperature signals all messed up (and even without the help from volcanos) and so does an Antarctic ice core. Playing with carbon cycle models or fiddling with old ocean measurements or counting U.S. temperature records (of which U.S. public probably don't even care) don't help. So we get our weather extreme and disaster analysis methods in shape and then we just sit back and wait. It won't be long wait, though, as the aerosol forcing (from transportation for example) diminishes and GHG warming really starts to kick in fast. That's air pollution control for you. Speaking about pollution control, we are just glad that British river dwellers are doing little bit better these days, partly due to toxic waste management. In middle all this, we are wondering if solar cycle affects Madden-Julian oscillation and if Bering Sea would get a nice swimming temperature, if we would double the CO2 in the air.



Climate mythbusting at Lane Cove, Sydney on Feb 28

Posted on 14 February 2012 by John Cook

I will be giving a presentation Climate Change: Busting the Myths at Lane Cove, Sydney on Feb 28, organised by Sustain Me Consulting. The evening will feature climate mythbusting followed by examples of local climate action. The mythbusting will take an interesting, interactive approach. The audience will break into groups and select 3 climate myths they'd most like to hear about. I'll then attempt to debunk the myths. Next, the audience will rate my effort, deciding whether the myths have been busted or not. Given that I have no idea what myths will get thrown at me, the evening could be an engaging, illuminating experience for all... or it could be a train wreck. Either way, bring popcorn! You can register for the event here (there are around 20 spots still available).

On a unrelated note, as far as photos of climate communicators go, I'm not even in John Abraham's league:



2000 Years of Climate Reconstructed from Pollen

Posted on 14 February 2012 by Robert Way

A window into climate change in North America over the past 2,000 years using pollen data

Researchers at the University of Ottawa Laboratory for Paleoclimatology and Climatology have reconstructed temperature for the for the last 2,000 years in North America using 748 pollen sites from the North American pollen database (NAPD), the Whitmore modern pollen dataset for calibration and the Modern Analog Technique (MAT). The Modern Analog Technique uses the modern distribution of pollen throughout a region and compares it to former distributions (usually collected from Lake Cores) to estimate changes in both temperature and precipitation (Figure 1). This technique allows for temperatures to be reconstructed for the warmest month of a calendar year across the many biomes of North America.

Pollen from lake sediment cores has proven to produce reliable climate reconstructions on centennial to millennial scales.  A lake sediment core contains pollen grains from different taxa (anywhere from 15 to 135 taxa are used, this reconstruction used 63 taxa) and the deeper in the core, the further back in time the pollen was deposited.  Certain vegetation assemblages and thus pollen  represent specific climate conditions (temperature and moisture).  The modern analogue technique (Overpeck, 1985) was used to find the modern site that most closely matches a fossil site in terms of pollen percentages down-core using the squared chored distance (SCD metric).  In this manner the climate can be reconstructed through time.

Figure 1: Location of samples used in this study (A) Modern (B) Fossil



Finnish translation of The Scientific Guide to Global Warming Skepticism

Posted on 13 February 2012 by John Cook

Since launching in December 2010, the English version of the Scientific Guide to Global Warming Skepticism has been downloaded 812,000 times and is being used by teacher associations, museums, websites, student groups and other organisations. The Guide has also been translated into 16 languages. The latest translation is Finnish. Many thanks to Ari Jokimäki, Kaj Luukko, Esko Pettay and Janne Tuukkanen for their contributions to the translation.

Note to other translators:

If you'd like to translate the Guide into another language, there are two documents to help you: a two-column Word document with all the English text in one column and a blank column to place the translated text, plus a PDF Overview of the Guide to clearly mark each section.

Please download the Word document and email me back the document with translated text. I'll then insert the translated text into the existing design. But best first to contact me to ensure noone else is already working on your language. Note: the following languages have already been translated:



2012 SkS Weekly Digest #6

Posted on 13 February 2012 by John Hartz

SkS Highlights

Rob Painting's Global Sea Level Rise: Pothole To Speed Bump? and John Cook's Book review of Michael Mann's The Hockey Stick and the Climate Wars garnered the most comments this past week. The title of Michaels Misrepresents Nordhaus and Scientific Evidence in General by Alex C  speaks for itself.

Toon of the Week

 Toon of the Week 2012-06



Peter Hadfield on Himalayan glacier melt

Posted on 13 February 2012 by Rob Honeycutt

Journalist Peter Hadfield has produced a new Youtube video regarding all the headlines that were splashed across the news circuits last week claiming that there's been "No Melt in 10 Years."  

Peter's MO has become the simple act of "reading the actual research."  In this video he applies this unique journalistic technique to Jacob et. al 2012, "Recent contributions of glaciers and ice caps to sea level rise" and gets us to the bottom of what the rest of the media manages to miss.



A prelude to the Arctic melting season

Posted on 12 February 2012 by Neven

This is a summary/re-write of a recent blog post on the Arctic Sea Ice blog.

We are entering the final stage of the freezing season in the Arctic. The sea ice has reached all shores, and where there aren't shores it reaches as far south as the winds and currents will permit. Or, at least it used to go like that.

Ice growth had been relatively slow in sea ice regions like the Barents Sea, Kara Sea and Greenland Sea (see this Cryosphere Today map to get an idea of where the regions are), but nothing (much) out of the ordinary. However, in the past two weeks a persistent weather pattern emerged that is bringing Siberian cold to almost all of Europe, but warm air and water to Novaya Zemlya, the large island that separates the Barentsz and Kara Seas.

The effect this has had can clearly be seen when comparing yesterday's sea ice concentration image with those of previous years on the same date:


image courtesy of the University of Bremen



The Year After McLean - A Review of 2011 Global Temperatures

Posted on 11 February 2012 by dana1981

In The Day After McLean we examined a prediction by data analyst and member of the Australian Climate Science Coalition John McLean regarding the 2011 global average surface temperature:

"it is likely that 2011 will be the coolest year since 1956 or even earlier"

The title of the post was a reference to the film The Day After Tomorrow (which depicts extremely rapid global cooling) because of the rapid cooling which would have to occur for McLean's prediction to come to fruition, as illustrated in Figure 1.

McLean failure

Figure 1: NCDC global average surface temperature from 1880 through 2010 (blue), McLean's 2011 prediction (orange), and the actual 2011 NCDC temperature (purple).



NASA Mission Takes Stock of Earth's Melting Land Ice

Posted on 10 February 2012 by John Hartz

This article is a reprint of a news release posted by the US Jet Propulsion Laboratory on  Feb 8, 2012

In the first comprehensive satellite study of its kind, a University of Colorado at Boulder-led team used NASA data to calculate how much Earth's melting land ice is adding to global sea level rise.

Using satellite measurements from the NASA/German Aerospace Center Gravity Recovery and Climate Experiment (GRACE), the researchers measured ice loss in all of Earth's land ice between 2003 and 2010, with particular emphasis on glaciers and ice caps outside of Greenland and Antarctica.

The total global ice mass lost from Greenland, Antarctica and Earth's glaciers and ice caps during the study period was about 4.3 trillion tons (1,000 cubic miles), adding about 0.5 inches (12 millimeters) to global sea level. That's enough ice to cover the United States 1.5 feet (0.5 meters) deep.

"Earth is losing a huge amount of ice to the ocean annually, and these new results will help us answer important questions in terms of both sea rise and how the planet's cold regions are responding to global change," said University of Colorado Boulder physics professor John Wahr, who helped lead the study. "The strength of GRACE is it sees all the mass in the system, even though its resolution is not high enough to allow us to determine separate contributions from each individual glacier."



The real doping scandal: Weather on steroids

Posted on 10 February 2012 by Tom Smerling

Is the increase in extreme weather due to climate change?    This animated cartoon from the National Center from Atmospheric Research (NCAR) provides perhaps the clearest — and certainly the most entertaining — answer yet. 

For more on the latest science exploring the links between extreme weather and climate change, check out NCAR's Doping the Atmosphere, and Extreme Weather Forensics; and SkS's Extreme Events Increase With Global Warming.

For a “bite sized” version of the steroids metaphor, check out “Putting the atmosphere on steroids” at Climate Bites, which also has a good post by John Russell about critics of The Escalator missing the point of the graphic.



Book review of Michael Mann's The Hockey Stick and the Climate Wars

Posted on 9 February 2012 by John Cook

The Hockey Stick and the Climate Wars by Michael Mann takes us into the heart of the climate change controversy via the scientist standing in the eye of the storm - Michael Mann. He provides an eye-opening account of the lengths the opponents of climate science will go to in their campaign to slander climate scientists and distract the public from the realities of human caused global warming.

Before jumping into the dogfight, the book tells us the human story of how Mann got started in science. It was surprising to learn that his PhD began with the notion that natural variability might be greater than what climate scientists thought. I also didn't realize he'd coined the term "Atlantic Multidecadal Oscillation" (AMO) off the cuff in an interview (that's the kind of trivia that a science geek like me delights in). Ironically the AMO and natural oscillations are often invoked by contrarians to cast doubt on the human influence on global warming.



Michaels Misrepresents Nordhaus and Scientific Evidence in General

Posted on 9 February 2012 by Alex C

The Wall Street Journal’s 27 January 2012 climate change op-ed came under harsh and swift criticism for being signed by only two climate scientists and fourteen other non-climate scientists, criticism most notably demonstrated by a group of 38 climate scientists in a response letter that the Journal has agreed to publish (to its credit).  Apparently this strong show from experts in the field has not stopped Dr. Patrick Michaels, though, from nailing his colors to the mast at Forbes, and both promoting misrepresentation of the research of another scientist - Professor William Nordhaus - and misinforming the public on the consensus of evidence in climate science.

Michaels continuing the misrepresentation of Dr. William Nordhaus

Michaels starts his opinion piece by first contradicting another op-ed that appeared in the New York Times, written by Andrew Revkin.  In his piece, Revkin cites an email exchange that he had with Sterling Professor of Economics at Yale University, Dr. William Nordhaus.  For some quick background info, the Wall Street Journal op-ed stated:



Volcanic Influence on the Little Ice Age

Posted on 8 February 2012 by dana1981

The causes and even start and duration of the Little Ice Age (LIA), a global cooling event of approximately 0.5°C over several centuries ending in the late 19th Century, has been a challenge for climate scientists to pin down, with many possible contributing factors.  A very interesting new paper by Miller et al. (2012) seeks to answer these questions by simulating the climate response to a number of large volcanic eruptions during the LIA timeframe.  As the authors note, the challenge lies not only in determining the cause of the LIA, but when the event even started:

"...the natural radiative forcings are either weak or, in the case of explosive volcanism, shortlived [Robock, 2000], thus requiring substantial internal feedback. The LIA is particularly enigmatic. Despite extensive historical documentation and a wide array of proxy records that define climate change during the past millennium [Mann et al., 2008], there is no clear consensus on the timing, duration, or controlling mechanisms of the LIA."

A similar paper, Anderson et al. (2008), was previously discussed here.

The Data

Miller et al. used precisely-dated records of ice-cap growth from Arctic Canada and Iceland in their attempt to assess the timing and duration of the LIA.  The ice caps exhibit little or no flow, and thus preserve rooted tundra vegetation that was alive at the time of ice-cap expansion.  This enabled the scientists to use carbon dating on the vegetation.  This process accurately dates the time when snowline dropped below the vegetation altitude, killing the plants, and remained on average below that site until the summer warmth of recent decades.  The locations from which Miller et al. gathered vegetation samples are illustrated in Figure 1.

Figure 1

Figure 1: Arctic Canada sites with recently exposed entombed plants dated younger than 800 AD (circles) and older than 800 AD (triangles); Hvítárvatn, Iceland (square); Greenland temperature borehole site and sea ice record on the North Iceland shelf (round).



New research from last week 5/2012

Posted on 7 February 2012 by Ari Jokimäki

Scientists are telling about whats and whys:

Ozone has weekly lows and highs.
Range shifts up north for butterflies.
Cloud height tells us about falling skies.
Open up Bering strait and the seesaw dies.
Earthquakes cool groundwater unless it's lies.
In the age of dinosaurs there were not much ice,
but it was volcanism that started the age of little ice.
Knowledge of pressure driven tsunamis makes us wise.
Northern hemisphere is warming at a rate that is surprise.
Does the India's DTR increase disturb the production of rice?
For climate permafrost carbon feedback is another warming slice.

Yet another weekly paper batch, oh, isn't that nice...



Global Sea Level Rise: Pothole To Speed Bump?

Posted on 7 February 2012 by Rob Painting

As indicated in a press release from the NASA Jet Propulsion Lab last year, short-term trends in global sea level rise are greatly affected by temporary exchanges of water mass between the land surface and ocean - creating 'potholes' and 'speed bumps' in the sea level record. This a consequence of changes in precipitation (rainfall & snow) resulting from the El Niño-Southern Oscillation (ENSO).

During La Niña the sea surface is cooler-than-normal and rainfall is concentrated over land, which leads to a temporary fall in global sea level. With El Niño the surface of the tropical Pacific Ocean becomes warmer-than-normal, and rainfall gets concentrated over the ocean. This, combined with the drainage of water from land, causes a temporary spike in global sea level.

ENSO is principally responsible for the large year-to-year fluctuations evident in the global sea level record, but neither of these two phenomena (El Niño/La Niña) alter the long-term sea level rise which results from the melting of land-based ice, and the thermal expansion of the oceans as they warm. They do, however, cause sufficient 'noise' to obscure the long-term sea level rise when viewed at short intervals.

In the last two years two back-to-back La Niña have temporarily lowered sea level, but La Niña appears to have weakened in recent months and accordingly we would expect an uptick in sea level rise as conditions move closer to neutral. A quick look at AVISO confirms this, see Figure 1.

Figure 1 - The reference mean sea level since January 1993 (left) is calculated after removing the annual and semi-annual signals. A 2-month filter is applied to the blue points, while a 6-month filter is used on the red curve. By applying the postglacial rebound correction (-0.3 mm/year), the rise in mean sea level has thus been estimated as 3.18 mm/year. Image from AVISO.




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