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Tuesday, January 1, 2013

SkS: 2012 in Review - a Major Year for Climate Change

by Dana Nuccitelli, Skeptical Science, January 1, 2012
With 2012 now in the books, let's take a look back at some of the biggest climate-related events of the year.  Here we'll examine some of the most significant scientific papers, debunked myths, climatic events, and steps taken towards solving the climate problem, as determined in part by the most widely-viewed Skeptical Science blog posts of 2012.  Let's begin with two of the most significant climatic events of the year.

Climatic Events of 2012 - Sea Ice Record and Sandy

There are two clear climatic event frontrunners in terms of impacts on people, the climate, and public awareness of climate change: the record-shattering Arctic sea ice melt, and Hurricane Sandy

Record Arctic Sea Ice Melt

"The scientific literature is clear that the current record Arctic sea ice decline is beyond what has occurred due to natural variability for at least the past several millennia, certainly beyond what occured circa 1940, and that human influences are primarily responsible for the rapid rate of the death spiral."
The extent of the record is illustrated in the Arctic sea ice Escalator:

sea ice escalator

Figure 1:  NSIDC September Arctic sea ice extent (blue diamonds) with "recovery" years highlighted in red, vs. the long-term sea ice decline fit with a second order polynomial, also in red.
The 2012 Arctic sea ice melt was so large, that it became clear that We're gonna need a bigger graph to keep track of the death spiral.
In Lessons from Past Climate Predictions: Arctic Sea Ice Extent 2012 Update, we also saw that statistical predictions of annual Arctic sea ice minimum extent based on the long-term Arctic sea ice death spiral are more accurate and realistic than denial-based optimistic predictions that sea ice will somehow magically recover to previous levels.

Hurricane Sandy

In Hurricane Sandy and the Climate Connection, we looked at the scientific evidence regarding how we know human-caused global warming made the hurricane's impacts worse.  As John Cook put it,
storm fuel
Peter Sinclair put together an excellent Yale Forum Video: A ‘Play-by-Play’ on Sandy with Kerry Emanuel
We also debunked several myths associated with the Arctic sea ice record and Hurricane Sandy - more on these below.

New Climate Research in 2012

There was of course an immense body of new climate research in 2012, only a small selection of which we were able to examine at Skeptical Science.

Global Warming Caused by Humans

Gillett et al. (2012) and Wigley and Santer (2012) both added to the body of scientific literature determining the causes of global warming.  The Wigley and Santer results were added to the graphics created in the 2nd-most widely-read Skeptical Science post of 2012, A Comprehensive Review of the Causes of Global Warming.  All of the global warming attribution research has found that humans are responsible for close to 100% of the observed global warming over the past half century (Figure 2).
attribution 50 yr
Figure 2: 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, light green), Lean and Rind 2008 (LR08, purple), Huber and Knutti 2011 (HK11, light blue), Gillett et al. 2012 (G12, orange), and Wigley and Santer 2012 (WS12, dark green).

Ocean Heat Content Shows Global Warming Continues

Because over 90% of global warming goes into heating the oceans, the improved ocean heat content measurements in Levitus et al. (2012) were an important climate advancement.  These results were also used in the first Skeptical Science team scientific publication, Nuccitelli et al. (2012), which produced this useful figure showing that global warming continues to rise:
Fig 1
Figure 3: Land, atmosphere, and ice heating (red), 0-700 meter OHC increase (light blue), 700-2,000 meter OHC increase (dark blue).  From Nuccitelli et al. (2012).
In fact, the warming of the oceans since 1961 consists of a heat accumulation equivalent to two Hiroshima bomb detonations per second, every second over the past 50 years, and an even faster rate over the past two decades.

Review of Misinformation Research

The same week as Nuccitelli et al. was published, John Cook was co-author on another paper, Lewandowski et al. (2012), which provided a comprehensive review of research into misinformation.

The CO2-Temperature Lag Clarified

Shakun et al. (2012) Clarified the CO2-Temperature Lag.  We summarized the intriguing results of this paper:
"...the initial warming was indeed triggered by the Milankovitch cycles, and that small amount of orbital cycle-caused warming eventually triggered the CO2 release, which caused most of the glacial-interglacial warming.  So while CO2 did lag behind a small initial temperature change (which mostly occurred in the Southern Hemisphere), it led and was the primary driver behind most of the glacial-interglacial warming.
According to the Shakun et al. data, approximately 7% of the overall glacial-interglacial global temperature increase occurred before the CO2 rise, whereas93% of the global warming followed the CO2 increase."

Anomalous Sea Level Rise

SkS provided a video of Jerry Mitrovica's popular talk about his research into sea level rise, and the fact that the current rate of rise is faster than at any time over the past 10,000 years, since the last ice age ended.

The Biggest Climate Myths of 2012

Global Warming due to Humans, not the Sun

The 3rd-most widely-read Skeptical Science post of 2012 was a recent one, debunking a new myth by showing that the 'leaked' IPCC report explains why Global Warming is NOT Due to the Sun (Figure 4).
Figure 4: Global temperature (red, NASA GISS) and Total solar irradiance (blue, 1880 to 1978 from Solanki, 1979 to 2009 from PMOD), with 11-year running averages.

Continued Global Warming Over the Past 16 Years

Perhaps the contrarians' favorite climate myth in 2012 was that global warming magically stopped 16 years ago. This myth was first invented in an article by David Rose which included an interview with Judith Curry, but the myth had conveniently been Pre-Bunked by Nuccitelli et al. (2012) just days earlier. Nevertheless, Rose and Curry Doubled Down on their Global Warming Denial via the common denial practice of cherrypicking, which we also debunked.
The denialist use of myth of course did not stop there; it was most recently repeated by Christopher Monckton, and we were forced to give Monckton and Co. a lesson about what "global warming" is.

Gish Gallops Galore

The 'global warming stopped' myth was also repeated in The Latest Pre-Bunked Denialist Letter in Lieu of Real Science and a previous Denialist Plea for Climate Change Inaction, along with a great many other myths in true Gish Gallop fashion.  We also debunked a Gish Gallop from former Greenpeace figure Patrick Moore, and two by Bob Carter and Ian Plimer (published in the same week!), as well as Matt Ridley's nonsense in WIRED magazine.  Another Gish Gallop letter by some former NASA employees was also published and debunked, as were Fritz Vahrenholt's Gish Gallop interview in Der SpiegelJohn Christy's congressional testimony myths, and Lindzen's London Illusions.
Clearly publishing massive quantities of misinformation in the mainstream media remains the climate contrarians' favorite way to dispute mainstream climate science, whereas their efforts to publish real scientific research through the standard peer-review method remain quite infrequent.

Curry's Uncertainty Ewok

Interestingly, by far the most widely-read Skeptical Science post of 2012 was in regards to Judith Curry's Certainty Monster vs. The Uncertainty Ewok, debunking the myth that there is too much uncertainty about human-caused global warming to take action. Gunnar also examined how Curry has misused the Italian Flag approach in evaluating climate uncertainty.

Watts Up With Misinformation

We also critiqued the fundamental flaws in Anthony Watts' draft paper, which wrongly attempted to argue that contrary to Watts' own prior research, the surface temperature record is significantly influenced by the urban heat island effect. There has been no word about that draft paper since we exposed its flaws. That didn't stop Watts from going on PBS False Balance Hour and claiming the surface temperature record is unreliable, amongst other myths.

Big Year for The Escalator

After its creation in late 2011The Escalator became Skeptical Science's most popular myth debunking tool.  Speaking of PBS, The Escalator was featured in the program Climate of Doubt.  It was most recently used on the floor of the US Senate in an excellent speech by Senator Sheldon Whitehouse.
The Escalator has also undergone several revisions, the latest of which will be announced in a blog post in the near future. In addition to being used in a great many of Skeptical Science's own myth debunkings, The Escalator was used by many other websites and news outlets. We also created Vanishing Arctic Sea Ice: Going Up the Down Escalator. All of Skeptical Science's animated graphics are free for reuse, and available on our Animations page.

Sandy and Sea Ice Myths Debunked

As noted above, we also debunked the myth that climate change did not impact Hurricane Sandy in WSJ, Sandy, and Global Warming - Asking the Right Questions.  We also debunked the myth that summer Arctic Storm caused the Record Sea Ice Minimum.

IPCC Temperature Projections On the Money, Contrarians Not So Much

While we recently saw that the IPCC has been remarkably accurate in projecting global surface temperature changes, we also saw that John McLean's prediction was remarkably wrong, and his fellow climate contrarians have not performed very well either.
Predictions Comparison
Figure 5: IPCC temperature projections (red, pink, orange, green) and contrarian projections (blue and purple) vs. observed surface temperature changes (average of NASA GISS, NOAA NCDC, and HadCRUT4; black and red) for 1990 through 2012.

Climate Change Linked to Extreme Weather

While certain climate contrarians tried to muddy the waters linking climate change to extreme weather, we showed that the scientific literature has found a clear link between human-caused global warming and the frequency and/or intensity of many types of extreme weather.

Human-Caused CO2 Increase Cleudo

In Climate Change Cluedo: Anthropogenic CO2, we went step-by-step through the evidence that shows why it's settled science that humans have caused the increase in the amount of CO2 in the Earth's atmosphere.

The Climate Problem, and Solving it

"If we continue forward on our current path, catastrophe is not just a possible outcome, it is the most probable outcome.  And an intelligent risk management approach would involve taking steps to prevent a catastrophic scenario if it were a mere possibility, let alone the most probable outcome."
Despite the the lack of progress at the Doha international climate conference, there is some Hopeful News.  Many countries and regions took steps to implement greenhouse gas emissions reductions policies in 2012, including Mexico, Australia, California, Japan, South Korea, China, and Québec. Although we're running out of time, it's not yet too late to avert a climate crisis, and although international negotiations continue to progress far too slowly, that is not preventing many countries and regions from acting. 
We must continue this progress in 2013 to get our greenhouse gas emissions under control as soon as possible. We at Skeptical Science will continue our efforts to aide in that goal by communicating climate science and debunking myths in the coming year. 
The good news is that climate realists appear to have surpassed climate denialists in terms of communication, as the Climategate debacle has not been repeated in the past three years. Instead, new myths have been rapidly debunked before they've spread through the media into the public awareness, and mainstream media willingness to cover the climate issue appears to be on the rise.  We must continue and accelerate this progress, raising public awareness of the climate threat in 2013, and putting pressure on leaders to take serious steps to solve the problem.

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