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- Public talk: Global Warming - The Full Picture
- New temperature record for the Arctic in 2011
- NASA scientists expect more rapid global warming in the very near future (part 1)
- Patrick Michaels Continues to Distort Hansen 1988, Part 2
- New research from last week 3/2012
- Patrick Michaels Continues to Distort Hansen 1988, Part 1
- Debunking Handbook: update and feedback
- The National Center for Science Education defends climate science in high schools
- 2012 SkS Weekly Digest #3
- National (US) Strategy Proposed to Respond to Climate Change’s Impacts on Fish, Wildlife, Plants
- 2011 Hottest La Niña Year on Record, 11th-Hottest Overall
- How do Climate Models Work?
- A Comprehensive Review of the Causes of Global Warming
- Arctic methane outgassing on the E Siberian Shelf part 2 - an interview with Dr Natalia Shakhova
- Lessons from the Whitehouse-Annan Wager
- New research from last week 2/2012
- Patrick Michaels: Serial Deleter of Inconvenient Data
- 2012 SkS Weekly Digest #2
- Puget Sound, Under Threat From Ocean Acidification, Put on "Waters of Concern" List
- Katharine Hayhoe's labour of love inspires a torrent of hate
- Arctic methane outgassing on the E Siberian Shelf part 1 - the background
- Gillett et al. Estimate Human and Natural Global Warming
- U.S. 2011: The Wet Get Wetter, the Dry Get Drier
- Climate and Sea Level: An Emerging Hockey Stick
- Climate Change Denial and the Media - Banishment of Science Reality
- Just Science app shows climate change is happening in pictures anyone can understand
- Lean and Rind Estimate Human and Natural Global Warming
- New research from last week 1/2012
- 2011 Year in Review (part 2)
- 2012 SkS Weekly Digest #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?
Public talk: Global Warming - The Full Picture
Posted on 27 January 2012 by John Cook
Since Skeptical Science won the Australian Museum Eureka Prize, I've noticed two tangible changes. Firstly, the level of criticism and scrutiny that Skeptical Science receives from those that reject anthropogenic global warming has increased an order of magnitude. Almost without exception, the criticisms neatly avoid the science presented at SkS and instead focus on big issues like the buttons in our margin, comment moderation and the fact that our header graphic is photoshopped (an exception being a science-based critique by Lucia from Blackboard which led to an update of an SkS post). The other change is an increase in the invitations I've received to give public talks. Some of these talks are starting to make their way online so I thought I might start posting them on SkS (perhaps the invitations will drop off once people actually see my attempts at public speaking).
In November last year, I was invited to give a talk by TweedCAN, a group in the Tweed Shire just south of the Queensland/New South Wales border, that aim to reduce carbon emissions through local action (they're a dynamo of a group, having initiated a number of exciting local projects involving renewable energy). They asked me to talk about the science of climate change so I gave a presentation "Climate Change: The Full Picture". In all the public talks I'd given up until then, surprisingly I'd never once had a contrarian stand up in the audience and confront me with a climate myth. Finally, that disappointing streak ended at Tweed with a number of challenging questions (and it was all captured on video):
New temperature record for the Arctic in 2011
Posted on 27 January 2012 by Neven
NOTE: Reposted from Neven's blog post of the same name, via ClimateProgress from the WWF Climate Blog, this piece by Nick Sundt:
Last week NASA released data showing that last year temperatures in the Arctic rose beyond the record established in 2010 -- setting a new record for 2011. News of the record Arctic temperatures follows a series of alarming developments related to the Arctic in recent months.
The surface temperature anomaly for the region extending from 64°N to 90°N, from 1880 through 2011, in degrees Celsius above or below the temperature during the 1951-1980 base period. The figures shows that temperatures have risen substantially since 1880 and that the rate of increase has been especially rapid since the late 1970s. Source: data from NASA Goddard Institute for Space Studies, Combined Land-Surface Air and Sea-Surface Water Temperature Anomalies, Zonal annual means (Click for larger graphic).
NASA scientists expect more rapid global warming in the very near future (part 1)
Posted on 26 January 2012 by Rob Painting
As a recent SkS post by Dana Nuccitelli has pointed out global warming hasn't stopped, despite a recent lull in global surface temperatures. The oceans, which are the main heat sink for global warming, have scarcely skipped a beat in soaking up heat. The hiatus in global surface temperatures appears to simply be a reflection of natural variability, principally the exchange of heat between the ocean surface and the atmosphere. But we shouldn't expect this to last much longer. Eventually that ocean heat buried in deeper layers will come back to the surface, and we'll experience the warm phase of this natural cool/warm (La Niña/El Niño-based) cycle.
As if to reinforce this very point, a group of scientists at the NASA Goddard Institute for Space Studies (NASA GISS), have released an analysis of global temperatures in 2011, and near-future prospects. They find that 2011 was the 9th-hottest year on record (9 out of the 10 hottest years on record since 1880, have occurred in the 21st century), and that this cool-ish year (by 21st century standards, but hot by 20th century standards) was largely due to the cooling influence of a quiet phase of the 11 year-long solar cycle (small changes in the intensity of sunlight reaching Earth), and La Niña which has been dominant over the last 3 years (See figure 1). They conclude that the lull is an illusion, and that rapid warming of global surface temperatures is likely to resume in the next few years.
Figure 1 - Global monthly and 12-month running mean (average) surface temperature anomalies relative to the 1951-1980 base period (GISTEMP), and the 12-month running mean of the Nino 3.4 index of sea surface temperatures (an index of La Niña/El Niño intensity and duration). Image adapted from NASA GISS.
Patrick Michaels Continues to Distort Hansen 1988, Part 2
Posted on 25 January 2012 by dana1981
In Part 1 of this post, we examined Patrick Michaels' self-defense for deleting two of Hansen and colleagues' 1988 global warming projections in his 1998 testimony before Congress. As we saw, Michaels' excuse relied on a comment by Hansen that Scenario A was "business as usual." However, given that we did not follow a business-as-usual path from 1988 to 1998, and Scenario C was the most accurate representation of actual greenhouse gas (GHG) emissions, Michaels' presentation to Congress remains a distortion of Hansen's actual results.
Here in Part 2, we examine what Michaels' presentation to Congress should have looked like, had it been accurate, and what this tells us about the accuracy of Hansen's climate model and real-world climate sensitivity.
Recreating Michaels' Congressional Testimony Graphic
As noted in Part 1, if we're going to only show one emissions scenario, it should be the one closest to reality. In Michaels' case in his 1998 Congressional testimony, that should have been Scenario C. Currently, Scenario B is closest to the actual forcing, according to Skeie et al., but running about 16% too high (since 1988). Figure 1 reproduces Hansen's Scenario B with a 16% reduction in the warming trend, to crudely correct for the discrepancy between it and the actual radiative forcing. This might be what Michaels' graphic would look like if he were to give an accurate version of his presentation today:
Figure 1: Observed temperature change (GISTEMP, blue) and with solar, volcanic and El Niño Southern Oscillation effects removed by Foster and Rahmstorf (green) vs. Hansen Scenario B trend adjusted downward 16% to reflect the observed changes in radiative forcings since 1988, using a 1986 to 1990 baseline.
New research from last week 3/2012
Posted on 24 January 2012 by Ari Jokimäki
Q: Are Parisian air-conditioners making things all nice and cool or warming up the place? A: Warming up the place. Q: What is it that was travestically missing but has been found now? A: Energy. Q: What is the hypothesis that is constantly debunked by numerous peer-reviewed studies and gets yet another blow this week? A: Cosmic ray-climate connection. Q: As just about anything seems to affect North-Atlantic/Europe weather, does Indian summer monsoon do it too? A: Yes. Q: What is slowly increasing tropical Pacific east-west temperature gradient? A: Global warming. Q: What Alaskan treeline trees do when climate warms? A: Anything they feel like doing. Q: What lives longer if days get warmer but doesn't if only nights get warmer? A: Root. Q: How do you explain carbon dioxide increase during last glacial termination? A: With salt, of course. Q: What keeps AMOC running? A: Mountains.
We also have studies on orbital control of carbon cycle, positive low-level cloud feedback, different kinds of cloud feedbacks, tropical glaciers, global sea level, electromagnetic imaging of permafrost, 1988 land uptake of carbon, temperature control over tropical tropopause water vapor and clouds, and Canadian lake plankton.
Patrick Michaels Continues to Distort Hansen 1988, Part 1
Posted on 24 January 2012 by dana1981
We recently examined three examples of Patrick Michaels deleting inconvenient data in his presentations of other scientists' research. The first and most egregious of these examples occurred in 1998, when Michaels testified before Congress and deleted two of the three global warming projections from Hansen et al. (1988). Rather than admit and apologize for this blatant distortion of the work of Hansen and colleagues, Michaels has responded by attempting to defend the indefensible. However, his excuses for deleting Hansen's Scenarios B and C are based on erroneous assumptions as detailed below. Consequently, his presentation to Congress remains a distortion of Hansen's actual results.
Figure 1: Radiative forcing contributions from 1988 to 1998 from CO2 (dark blue), N2O (red), CH4 (green), CFC-11 (purple), and CFC-12 (light blue) in each of the scenarios modeled in Hansen et al. 1988, vs. observations (NOAA).
Debunking Handbook: update and feedback
Posted on 23 January 2012 by John Cook
When we published the Debunking Handbook, I have to admit, we completely underestimated the impact it would make. A few days after the launch, it suddenly went viral with over 150,000 downloads in a single day. This week, it just ticked over 400,000 downloads. We always planned that the Handbook would be useful not just for climate myths but for communicators having to deal with any type of misinformation. Nevertheless, it was surprising to see the Handbook featued on websites as diverse as Richard Dawkins and Silobreaker. A website devoted to debunking MLM myths saw it as "useful when debating with brainwashed members of MLM organizations". A Muslim forum speculated that it "Should be useful when engaging people who believe lies about Islam". Currently, several educators are looking to integrate it into their curriculum.
Here are some excerpts from reviews of the Debunking Handbook:
"I simply cannot believe that John Cook of Skeptical Science and psychologist Stephan Lewandowsky managed, in just 8 pages, to create something as magnificent as their new Debunking Handbook... As someone who teaches science communication, I’m going to recommend Cook’s and Lewandowsky’s handbook to as many folks as I can find."
Chris Mooney, Desmogblog"...a must-read summary of the scientific literature on how to extract pernicious myths from people’s minds and restore fact-based knowledge."
Brad Johnson, Think Progress"I have to say that Cook and Lewandowsky have done a great job of clearly and succinctly outlining the challenge(s) and providing actionable paths forward to deal with them... In short, consider the Debunking Handbook a must read and a must keep reference."
A Siegel, Daily Kos
The National Center for Science Education defends climate science in high schools
Posted on 23 January 2012 by John Cook
The war on climate science is waged on many fronts, with one growing element being high schools. One Washington school board placed a moratorium on showing "An Inconvenient Truth" in classrooms. A California school board has voted to include "multiple perspectives" on climate science. Another movement in Colorado gathered 700 signatures asking to remove climate science from curriculums. These are all manifestations of a growing movement to inject denial of human-caused global warming into school curriculums.
Stepping into the front line to defend climate science is the National Center for Science Education. The NCSE have a long history of defending evolution science in the classroom. Now they've launched their Climate Change Initiative, to defend and support the teaching of climate science. NCSE's executive director Eugenie C. Scott explains:
"We consider climate change a critical issue in our own mission to protect the integrity of science education. Climate affects everyone, and the decisions we make today will affect generations to come. We need to teach kids now about the realities of global warming and climate change, so that they're prepared to make informed, intelligent decisions in the future."
2012 SkS Weekly Digest #3
Posted on 23 January 2012 by John Hartz
SkS Highlights
John Mason's Arctic methane outgassing on the E Siberian Shelf part 2 - an interview with Dr Natalia Shakhova provides the insights of one of the world's leading experts on what's happening. Dana's A Comprehensive Review of the Causes of Global Warming is another SkS original article to be reposted on many climate science friendly websites. In How do Climate Models Work?, Kate nicely explains the basic workings of climate models in a manner that can be understood by the average person as well as by climate science geeks.
Toon of the Week
H/T to Joe Romm's Climate Progress website.
National (US) Strategy Proposed to Respond to Climate Change’s Impacts on Fish, Wildlife, Plants
Posted on 23 January 2012 by John Hartz
This is a reprint of a news release issued by the US Department of Interior on Jan 19, 2012
The draft National Fish, Wildlife and Plants Climate Adaptation Strategy, available for public review and comment through March 5, 2012, can be found on the web at www.wildlifeadaptationstrategy.gov
The strategy represents a draft framework for unified action to safeguard fish, wildlife and plants, as well as the important benefits and services the natural world provides the nation every day, including jobs, food, clean water, clean air, building materials, storm protection, and recreation.
“The impacts of climate change are already here and those who manage our landscapes are already dealing with them,” said Deputy Secretary of the Interior David J. Hayes. “The reality is that rising sea levels, warmer temperatures, loss of sea ice and changing precipitation patterns – trends scientists have definitively connected to climate change – are already affecting the species we care about, the services we value, and the places we call home. A national strategy will help us prepare and adapt.”
2011 Hottest La Niña Year on Record, 11th-Hottest Overall
Posted on 22 January 2012 by dana1981
How do Climate Models Work?
Posted on 21 January 2012 by climatesight
Guest post by Kate from Climate Sight.
This is a climate model:
T = [(1-α)S/(4εσ)]1/4
(T is temperature, α is the albedo, S is the incoming solar radiation, ε is the emissivity, and σ is the Stefan-Boltzmann constant)
An extremely simplified climate model, that is. It's one line long, and is at the heart of every computer model of global warming. Using basic thermodynamics, it calculates the temperature of the Earth based on incoming sunlight and the reflectivity of the surface. The model is zero-dimensional, treating the Earth as a point mass at a fixed time. It doesn't consider the greenhouse effect, ocean currents, nutrient cycles, volcanoes, or pollution.
If you fix these deficiencies, the model becomes more and more complex. You have to derive many variables from physical laws, and use empirical data to approximate certain values. You have to repeat the calculations over and over for different parts of the Earth. Eventually the model is too complex to solve using pencil, paper and a pocket calculator. It's necessary to program the equations into a computer, and that's what climate scientists have been doing ever since computers were invented.
A Comprehensive Review of the Causes of Global Warming
Posted on 20 January 2012 by dana1981
At Skeptical Science, we have several recent studies which have used a number of diverse approaches to tease out the contributions of various natural and human effects to global warming. Here we will review the results of these various studies, and a few others which we have not previously examined, to see what the scientific literature and data have to say about exactly what is causing global warming.
All of these studies, using a wide range of independent methods, provide multiple lines of evidence that humans are the dominant cause of global warming over the past century, and especially over the past 50 to 65 years (Figure 1).
Figure 1: Net human and natural percent contributions 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). This has been added to the SkS Climate Graphics Page.
Arctic methane outgassing on the E Siberian Shelf part 2 - an interview with Dr Natalia Shakhova
Posted on 19 January 2012 by John Mason
In December 2011, following a fresh flurry of sometimes conflicting media reports about methane outgassing on the East Siberia Arctic Shelf (ESAS), we decided to go and talk to the people doing the work on the ground. We are pleased to report that Dr Natalia Shakhova (NS below) of the University of Alaska in Fairbanks agreed to be interviewed by the author, on behalf of Skeptical Science, via email. Here are the responses, verbatim, to our questions.
Above: Bathymetric map (source - NOAA) of the Arctic with key features noted and the subject area highlighted in red.
SkS: In your JGR paper from 2010 you state that methane hydrate in Siberia can occur at depths as shallow as 20 m. Have any such remarkably shallow methane hydrate deposits on the ESAS been directly observed/sampled and if so, how could methane hydrate have formed at such depths?
NS: Yes, such shallow hydrates were sampled in Siberia. They form as a result of the so-called “self-preservation phenomenon” and they are termed “metastable”. This phenomenon has been intensively studied by Russian geologists starting in the late 1980s.
Lessons from the Whitehouse-Annan Wager
Posted on 18 January 2012 by dana1981
In 2008, David Whitehouse (former BBC science correspondent with an astrophysics doctorate) made a wager with James Annan (climate scientist and statistics expert) involving global temperature data. Whitehouse wagered that the temperature data from the British Hadley Centre and University of East Anglia (HadCRUT) would not break its record high annual global temperature, which at the time was set in 1998, by 2011. The BBC, which coordinated the bet, recently declared Whitehouse the winner, although as we will see below, the true outcome is not entirely clear.
Predictably, particularly given the extremely poor performance of climate "skeptics" when it comes to climate predictions, the usual climate denial enablers are trumpeting the Whitehouse "victory" far and wide.
However, the stars had to align for Whitehouse to have a chance to win this bet. 2005 and 2010 were hotter than 1998 in the two other major surface temperature data sets, and likely will be in the soon-to-be updated HadCRUT data as well. The current HadCRUT data (HadCRUT3) has a known cool bias because it excludes several large regions which lack temperature station coverage, and also happen to be warming quite rapidly (such as the Arctic). Additionally, short-term natural effects dampened human-caused global warming over much of the 2008-2011 period. Despite this fact, the long-term human-caused global warming trend continues ever upward underneath that short-term natural noise.
More important than the winner of the bet is what we can learn from it. The main lesson here is that short-term temperature changes are quite unpredictable, as natural effects can overwhelm the steady greenhouse gas-caused warming over short timeframes.
New research from last week 2/2012
Posted on 17 January 2012 by Ari Jokimäki
In this week's papers global warming is cancelled. Couple of studies almost make it look like northern hemisphere hasn't warmed at all. Antarctic snowmelt hasn't increased either, and mass loss of Svalbard glaciers is at least slowing down. One study does see a GHG effect but there still might be less warming than usually is projected. On the other hand, only modest warming does some nasty things to tropical insects and arachnids, and even without warming, ocean acidification is going to cost us billions and billions of dollars (I'm glad that Euro is our currency here in Finland).
Looking at other papers this week, I bet you wouldn't like to swim in Paleozoic tropical oceans. Scientists have done fancy tricks with Greenland ice core to reveal secrets of an old volcanic eruption. Lord Kelvin seems to be still doing science. Deforestation appears at least in some sense to be cool. We also have studies on sea level rise of southern Europe coast, North-Atlantic warming, Holocene abrupt climate changes, oceanic freshwater fluxes, and South Asia warming distribution.
Patrick Michaels: Serial Deleter of Inconvenient Data
Posted on 17 January 2012 by dana1981
Patrick Michaels is a research fellow at the Cato Institute think tank, the chief editor of the website World Climate Report, has been given a climate blog at the business magazine Forbes, and his articles are frequently re-posted at climate "skeptic" blogs like Watts Up With That (WUWT). Despite his clear conflict of interest (Michaels has estimated that 40% of his work is funded by the petroleum industry), many people continue to rely on him as a reliable source of climate information. This is an unwise choice, because Michaels also has a long history of badly distorting climate scientists' work. In fact, not only does Michaels misrepresent climate research on a regular basis, but on several occasions he has gone as far as to manipulate other scientists' figures by deleting parts he doesn't like.
Patrick Michaels is a serial deleter of inconvenient data.
2012 SkS Weekly Digest #2
Posted on 16 January 2012 by John Hartz
Issue of the Week
Using a scale of one to ten, with ten being "very user-friendly" and one being "barely user-friendly", please rate how user-friendly the SkS website is. What could be done to make the website more user-friendly from your perspective?
SkS Highlights
"Katharine Hayhoe's labour of love inspires a torrent of hate" by John Cook is this past week's "must read post." The SkS author team stands in solidarity with Katherine Hayhoe and other scientists who have been targeted by the extreme elements of the Climate Denial Spin Machine.
Toon of the Week
Puget Sound, Under Threat From Ocean Acidification, Put on "Waters of Concern" List
Posted on 16 January 2012 by Rob Painting
This is a re-post of a press release from the Center For Biological Diversity
OLYMPIA, Wash.— In its water-quality report to the Environmental Protection Agency, the state of Washington classified the entire Puget Sound as “waters of concern” because of ocean acidification’s threat to local shellfish and fish resources. This means the data show that ocean acidification is threatening the region’s ability to support fish and shellfish. It also makes the area a priority for more monitoring and assessment.
Katharine Hayhoe's labour of love inspires a torrent of hate
Posted on 15 January 2012 by John Cook
Katharine Hayhoe is a Texan-based climate scientist and in my opinion, one of the clearest, most engaging and effective climate communicators kicking around. She also happens to be an evangelical Christian. A great introduction to climate science, her faith and Katharine herself is found in this short 10 question piece which was part of Nova's The Secret Life of Scientists & Engineers series:
Further insight into what drives Katharine can be found in the following video where she discusses the Christian response to climate change. A core Christian value is a heart for the poor and vulnerable. Katharine provides one of the more concise and compelling summaries of why climate change is an important issue for Christians. Here's an excerpt (but do watch the full video):
As a Christian, we're told that God is not the author of fear. God is love. When we're acting out of fear, we're thinking about ourselves. When we act about love, we're not thinking about ourselves. We're thinking about others. Our global neighbours, the poor and disadvantaged, the people who don't have the resources to adapt. So I believe we're called first of all to love each other and second of all, to act.
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