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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Climate Hustle


Dana Nuccitelli is an environmental scientist at a private environmental consulting firm in the Sacramento, California area. He has a Bachelor's Degree in astrophysics from the University of California at Berkeley, and a Master's Degree in physics from the University of California at Davis.

Dana has been researching climate science, economics, and solutions since 2006, and has contributed to Skeptical Science since September, 2010.  He also blogs at The Guardian, and is the author of Climatology versus Pseudoscience.  He has published climate-related papers on various subjects, from the build-up of heat in the Earth's climate system to the expert consensus on human-caused global warming.

Follow him on Twitter.


Nuccitelli, D., Way, R., Painting, R., Church, J., & Cook, J. (2012). Comment on ocean heat content and Earth's radiation imbalance. II. Relation to climate shifts. Physics Letters A.

Cook, J., Nuccitelli, D., Green, S.A., Richardson, M., Winkler, B., Painting, R., Way, R., Jacobs, P., & Skuce, A. (2013). Quantifying the consensus on anthropogenic global warming in the scientific literature. Environmental Research Letters, 8(2), 024024+. 

Cook, J., Oreskes, N., Doran, P. T., Anderegg, W. R., Verheggen, B., Maibach, E. W., Carlton, J. S., Lewandowsky, S., Skuce, A. G., Green, S. A., & Nuccitelli, D. (2016). Consensus on consensus: a synthesis of consensus estimates on human-caused global warming. Environmental Research Letters, 11(4), 048002.

Cook, J., Nuccitelli, D., Skuce, A., Way, R., Jacobs, P., Painting, R., Honeycutt, R., Green, S.A. (2014). Reply to Comment on ‘Quantifying the consensus on anthropogenic global warming in the scientific literature: a Reanalysis’. Energy Policy. DOI: 10.1016/j.enpol.2014.06.002

Nuccitelli, D. A., Abraham, J. P., Benestad, R. E., & Mandia, S. A. (2013). Comment on: Akasofu, S.-I. On the Present Halting of Global Warming. Climate 2013, 1, 4–11. Climate, 1(2), 76-83.

Abraham, J., Cook, J., Fasullo, J., Jacobs, P., Mandia, S., & Nuccitelli, D. (2014). Review of the consensus and asymmetric quality of research on human-induced climate changeCosmopolis2014(1), 3-18.

Benestad, R. E., Hygen, H. O., Dorland, R. V., Cook, J., & Nuccitelli, D. (2013). Agnotology: learning from mistakes. Earth System Dynamics Discussions, 4(1), 451-505.

Nuccitelli, D., Richter, M. J., & McCall, B. J. (2005). A search for interstellar carbon-60. In IAU Symposium (Vol. 235, p. 236P).

Encrenaz, T., Bézard, B., Greathouse, T., Holmes, S., Richter, M., Nuccitelli, D., & Forget, F. et al. (2006, February). Ground-based high-resolution IR spectroscopy of Mars: H2O and H2O2 mapping, search for CH4, and determination of CO2 isotopic ratios. In Second Workshop on Mars Atmosphere Modelling and Observations, held February.


Recent blog posts

'The atmosphere is being radicalized' by climate change

Posted on 24 October 2016 by dana1981 &

Climate change’s impacts on extreme weather and society are becoming increasingly clear and undeniable. While we are making progress in solving the problem, we’re still moving too slowly, and one of the two political parties governing the world’s strongest superpower continues to deny the science. This led astrophysicist Katie Mack to make the following suggestion, related to a common refrain from Donald Trump and Republican Party leaders:

Maybe governments will actually listen if we stop saying "extreme weather" & "climate change" & just say the atmosphere is being radicalized

Global warming intensified Hurricane Matthew

Hurricane Matthew set a number of records. Its record-breaking rainfall and storm surge caused historic flooding and destructive winds along the coasts of Florida, Georgia, the Carolinas, and Virginia. Hillary Clinton touched upon the science linking global warming and hurricane impacts in a recent speech in Florida:



No longer taken seriously, we're seeing the last gasp of climate denial groups

Posted on 19 October 2016 by dana1981 &

The Global Warming Policy Foundation (GWPF) is an anti-climate policy advocacy group in the UK that often releases misleading scientific “reports.” The group also hosts annual lectures, and this year, they booked a room at the Royal Society. Many members of the Royal Society expressed concern that the GWPF would exploit the organization’s credibility, and asked that the event be cancelled

The Royal Society’s governing council met and decided to allow the event to proceed, for fear that cancellation would give it “an unwarranted higher profile.” As a spokesperson for the Royal Society told DeSmog UK:

The evidence shows us that the earth is warming and that recent warming is largely caused by human activities. Once that is accepted, there is scope for debate on the policy responses and that is the area that the GWPF claims to be interested in.

If the GWPF uses this opportunity to misrepresent the scientific evidence it would undermine the legitimacy of its views on policy responses to climate change.

The lecture was delivered by writer Matt Ridley, and predictably, as is the norm for Ridley, the first three-quarters of his talk indeed misrepresented the scientific evidence. While Ridley doesn’t deny the most basic aspects of human-caused global warming, he is a self-prescribed “lukewarmer;” a group that falls into the category of Stage 3 climate denial.

Ridley’s lecture is a 5,600-word Gish Gallop that would require a novel to fully debunk. However, he condensed his main arguments into four key points that are easily refuted:

Why do I think the risk from global warming is being exaggerated? For four principal reasons.

1. All environmental predictions of doom always are;
2. the models have been consistently wrong for more than 30 years;
3. the best evidence indicates that climate sensitivity is relatively low;
4. the climate science establishment has a vested interest in alarm.

We’ve solved previous environmental problems, so let’s not solve global warming?

Ridley’s first argument against the dangers of global warming is incredibly ironic. He claims that we have nothing to worry about because previous “environmental predictions of gloom” were wrong. But the reason his cited predictions of danger didn’t come to fruition, in most cases, is because we took action to stop them.



Pew survey: Republicans are rejecting reality on climate change

Posted on 6 October 2016 by dana1981 &

Climate scientists have 95% confidence that humans are the main cause of global warming over the past six decades. Their best estimate attributes 100% of global warming since 1950 to human activities90 to 100% of climate scientists and their research agree on this. Human-caused global warming is as settled as science gets.

Yet most Americans don’t realize it. Moreover, the more conservative a person’s ideology, the less likely they are to accept this scientific reality or to trust the scientific experts.

According to a new Pew Research Center poll, just 48% of Americans realize that the Earth is warming mostly due to human activity. Highlighting a vast partisan reality gap, 79% of liberal Democrats and just 15% of conservative Republicans answer the question correctly.

Science knowledge matters for Democrats, but not Republicans

Among social scientists, there’s an ongoing debate about whether facts can change peoples’ minds on scientific issues that have become politically polarized, like climate change. There’s some evidence that when conservatives have more scientific knowledge, it just gives them more tools to use in rejecting the scientific information that conflicts with their ideological beliefs.

Pew asked a variety of general science questions to test the correlation between scientific knowledge and acceptance of human-caused global warming. Overall, Democrats and Republicans got the same average score on these scientific questions, although liberal Democrats and conservative Republicans scored better than moderates in both parties. When it came to understanding that humans are causing global warming, Pew found that scientific knowledge makes a huge difference among Democrats, and no difference among Republicans.


However, previous research has shown that conservatives with climate-specific knowledge are more likely to accept climate realities.

For Democrats, ideology isn’t a factor because the main solutions to the problem (e.g. regulations and pollution taxes) don’t conflict with their ideological beliefs. Thus scientific knowledge determines whether they understand that humans are causing global warming. For three-quarters of American conservatives, their ideology prevents them from accepting that reality, regardless of their scientific literacy.



DOE charts show why climate doom and gloom isn't needed

Posted on 4 October 2016 by dana1981 &

A new report from the US Department of Energy paints a bright picture for our prospects to cut carbon pollution and prevent the most dangerous levels of climate change. The report looked at recent changes in costs and deployment of five key clean energy technologies: wind, residential solar, utility-scale solar, batteries, and LED bulbs. For each technology, costs fell between 41% and 94% from 2008 to 2015.


Cost reductions in five key clean technologies since 2008. Illustration: US Department of Energy

Good news for doom and gloom environmentalists 

Many who understand the realities and dangers of human-caused global warming are afraid that we’ll fail to avoid catastrophic climate change. Among this group, even positive climate stories are often viewed through a lens of pessimism, and we often see stories about the likelihood that we’ll miss climate targets.

However, it’s important to acknowledge the progress that’s being made, and retain a sense of hope and optimism that we can still avoid the worst climate consequences. This new DOE report highlights the fact that clean energy technology is quickly moving in the right direction, toward lower costs and higher deployment.



New MIT app: check if your car meets climate targets

Posted on 28 September 2016 by dana1981 &

In a new study published in the journal Environmental Science & Technology, with an accompanying app for the public, scientists at MIT compare the carbon pollution from today’s cars to the international 2°C climate target. In order to meet that target, overall emissions need to decline dramatically over the coming decades.

The MIT team compared emissions from 125 electric, hybrid, and gasoline cars to the levels we need to achieve from the transportation sector in 2030, 2040, and 2050 to stay below 2°C global warming. They also looked at the cost efficiency of each car, including vehicle, fuel, and maintenance costs. The bottom line:

Although the average carbon intensity of vehicles sold in 2014 exceeds the climate target for 2030 by more than 50%, we find that most hybrid and battery electric vehicles available today meet this target. By 2050, only electric vehicles supplied with almost completely carbon-free electric power are expected to meet climate-policy targets.


Cost-carbon space for light-duty vehicles, assuming a 14 year lifetime, 12,100 miles driven annually, and an 8% discount rate. Data points show the most popular internal-combustion-engine vehicles (black), hybrid electric vehicles (pink), plug-in hybrid electric vehicles (red), and battery electric vehicles (yellow) in 2014, as well as one of the first fully commercial fuel-cell vehicles (blue). Illustration: Miotti et al. (2016), Environmental Science & Technology.

The MIT app allows consumers to check how their own vehicles – or cars they’re considering purchasing – stack up on the carbon emissions and cost curves. As co-author Jessika Trancik noted,

One goal of the work is to translate climate mitigation scenarios to the level of individual decision-makers who will ultimately be the ones to decide whether or not a clean energy transition occurs (in a market economy, at least). In the case of transportation, private citizens are key decision-makers.

How can electric cars already be the cheapest?



New study undercuts favorite climate myth ‘more CO2 is good for plants’

Posted on 19 September 2016 by dana1981 &

A new study by scientists at Stanford University, published in the Proceedings of the National Academy of Sciences, tested whether hotter temperatures and higher carbon dioxide levels that we’ll see post-2050 will benefit the kinds of plants that live in California grasslands. They found that carbon dioxide at higher levels than today (400 ppm) did not significantly change plant growth, while higher temperatures had a negative effect.

The oversimplified myth of ‘CO2 is plant food’

Those who benefit from the status quo of burning copious amounts of fossil fuels love to argue that more carbon dioxide in the atmosphere will benefit plant life. It’s a favorite claim of climate contrarians like Matt Ridley and Rupert Murdoch.

World growing greener with increased carbon. Thirty years of satellite evidence. Forests growing faster and thicker.

It seems like a great counter-argument to the fact that carbon dioxide is a dangerous pollutant – a fact that contrarians often dispute. However, reality is far more complicated than the oversimplification of ‘CO2 is plant food.’ Unlike in the controlled environment of a greenhouse, the increasing greenhouse effect on Earth causes temperatures to rise and the climate to change in various ways that can be bad for plant life. We can’t control all the other variables the way we can in a greenhouse.



Trump and the Republican Party are doing Big Oil's bidding

Posted on 14 September 2016 by dana1981 &

Trump hires advisers with fossil fuel ties

Last month, Donald Trump added Brooke Rollins and Kathleen Hartnett-White to his economic advisory council. Rollins is president and CEO of the Texas Public Policy Foundation (TPPF), while Hartnett-White has worked for the TPPF and the CO2 Coalition (formerly the George C. Marshall Institute), all of which are part of the “web of denial” receiving funding from the fossil fuel industry.

Hartnett-White told POLITICO in an interview that rather than listen to the conclusions of the world’s foremost climate science experts as summarized in the IPCC reports, she favors a commission that would develop an “alternative scientific methodology” and would include the voices of the less than 3% of climate scientists who reject the consensus on human-caused global warming. 

She believes “the sun had a powerful role” in global warming. However, the sun has had an overall cooling effect on global temperatures over the past 60 years, as the IPCC reports have shown. She also loves fossil fuels and seems entirely opposed renewable energy and efforts to cut carbon pollution.



BBC climate coverage is evolving, but too slowly

Posted on 12 September 2016 by dana1981 &

For years, the BBC has been criticised for the false balance of its climate change coverage. And for years, the BBC has apparently been doing “ongoing work” to fix it. So far, however, this ‘reform’ has been more like a triumph of the middling. Yes, the BBC may broadcast less outright misinformation, but as a scientist and a citizen, I still feel let down by its continually careless handling of climate denial - most recently two weeks ago. This nod to mediocrity is a disservice to science, to public trust, and to the biggest news story in the world. And it is a huge, missed opportunity.

As a young PhD graduate working on climate change solutions, I am confronted daily by a world where the warnings of science are undercut by Fox ‘News’ and its ilk. It is a very different world to the trustworthy BBC broadcasts of David Attenborough and the Royal Institution Christmas Lectures that I grew up with, which helped inspire me to become a scientist. But as a recent BBC News segment by Science Editor David Shukman sadly reminded me, those worlds can too easily collide.

Shukman’s broadcast was an interesting one. An important perspective on the “political battle over the future of fuel” in the swing state of Ohio, and its implications for U.S. energy policy. I transcribed it here. It was all pretty benign until, halfway through, something in Shukman’s narration caught my ear (emphasis mine):

The problem with coal comes when you burn it. It releases carbon dioxide, which is blamed for global warming. Donald Trump saysthat isn’t a problem. But Hillary Clinton says it is, and she’s offering a greener future instead ...

While the debate rages over whether climate change is a threat or not

Shukman’s accompanying BBC blog post beats the same drum, outlining the candidates’ “starkly different visions of global warming”:

The Democratic Party contender says she believes in the science of climate change. By contrast, the Republican candidate talks down the threat of rising temperatures.

As harmless as they sound, words like “blamed”, “debate”, and “believe” - without careful context - are the currency of public confusion. “Who, exactly, blames carbon dioxide for global warming?” we are forced to wonder. Clinton? Liberals? Scientists? And who disagrees? Trump? Other politicians? Some scientists too? Most importantly, who’s right in this blame game?

For the record, carbon dioxide is not “blamed” for global warming - it “causes” it. That is the unequivocal scientific consensus the world over.



Conservative media bias is inflating American climate denial and polarization

Posted on 6 September 2016 by dana1981 &

A new study by a team of sociologists at Oklahoma State University has found political polarization on climate change is growing in the United States. Today’s Republicans are less likely than they were a decade ago to accept that the effects of global warming have begun, that humans are responsible, and that there is a scientific consensus on these questions. Democrats and independents are slightly more likely to answer these questions correctly today than a decade ago.

congress enviro scores

Global warming views by party controlling for education and era. Illustration: Dunlap et al. (2016)

Climate change is now more polarizing in the US than abortion or gay marriage. At the same time, climate denial has become the norm among Republican policymakers, as they’ve grown increasingly anti-environment. As the study notes:

What was once a modest tendency for Congressional Republicans to be less pro-environmental than their Democratic counterparts has become a chasm—with Republicans taking near-unanimous anti-environmental stances on relevant legislation in recent years, especially 2015.

congress LCV scores

League of Conservation Voters’ environmental voting scores U.S. Congress – by chamber and party. Photograph: Dunlap et al. (2016).



California has urged President Obama and Congress to tax carbon pollution

Posted on 29 August 2016 by dana1981 &

Last week, the California state senate passed Assembly Joint Resolution 43, urging the federal government to pass a revenue-neutral carbon tax:

WHEREAS, A national carbon tax would make the United States a leader in mitigating climate change and the advancing clean energy technologies of the 21st Century, and would incentivize other countries to enact similar carbon taxes, thereby reducing global carbon dioxide emissions without the need for complex international agreements; now, therefore, be it Resolved by the Assembly and the Senate of the State of California, jointly, That the Legislature hereby urges the United States Congress to enact, without delay, a tax on carbon-based fossil fuels; and be it further Resolved ... That all tax revenue should be returned to middle- and low-income Americans to protect them from the impact of rising prices due to the tax

Copies of the Resolution were sent to President Obama, Vice President Biden, House Speaker Ryan, Senate Majority Leader McConnell, and to all members of Congress representing California. The document specifically calls for the type of revenue-neutral carbon tax advocated by the grassroots organization Citizens’ Climate Lobby. Studies have shown that a rising carbon tax with all revenue returned to taxpayers would have a modestly beneficial impact on the economy, while cutting carbon pollution at faster rates than current policies.

California exerts its climate leadership

California has become the US leader in tackling global warming. 10 years ago, the state passed the Global Warming Solutions Act, requiring that its greenhouse gas emissions in 2020 be no higher than 1990 levels. California achieved that goal in 2010, 10 years early, and is among the lowest per-capita carbon polluting states

On the same day last week, the state legislature also passed a bill expanding the Global Warming Solutions Act, requiring a 40% cut in California’s carbon pollution from 1990 levels by 2030. In other words, California isn’t just calling on the federal government to take action on climate change; the state is leading the way.

It remains to be seen whether any climate legislation can survive in the current toxic partisan political climate of Washington DC. However, a revenue-neutral carbon tax has the best chance due to its bipartisan appeal. Its requirement that carbon polluters pay for the costs of their pollution appeals to the political left, while its free market, small government approach appeals to the political right. 

Revenue-neutral carbon tax is hard to dislike

By returning 100% of the taxed revenue to American households, the policy blunts the rising costs of energy produced by burning fossil fuels. In fact, studies project that a majority of Americans would receive a rebate larger than their increase in energy bills; only those who use the most fossil fuel energy would see costs rise more than the rebate.



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