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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., 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

Two-faced Exxon: the misinformation campaign against its own scientists

Posted on 25 November 2015 by dana1981 &

Investigative journalism by Inside Climate News (ICN) into Exxon’s internal documents revealed that the company was at the forefront of climate research, warning of the dangers posed by human-caused global warming from the late-1970s to the late-1980s. As Harvard climate historian Naomi Oreskes noted,

But Exxon was sending a different message, even though its own evidence contradicted its public claim that the science was highly uncertain and no one really knew whether the climate was changing or, if it was changing, what was causing it … Journalists and scientists have identified more than 30 different organizations funded by the company that have worked to undermine the scientific message and prevent policy action to control greenhouse gas emissions.

Exxon has responded to the ICN allegations by pointing out that over the past three decades, the company’s scientists have continued to publish peer-reviewed climate research.

Our scientists have contributed climate research and related policy analysis to more than 50 papers in peer-reviewed publications – all out in the open. They’ve participated in the United Nations Intergovernmental Panel on Climate Change since its inception – in 1988 – and were involved in the National Academy of Sciences review of the third U.S. National Climate Assessment Report.

Finally, I’ll note that we have long – and publicly – supported a revenue-neutral carbon tax as the most effective, transparent, and efficient way for governments to send a signal to consumers and the economy to reduce the use of carbon-based fuels.

While the ICN investigation focused on Exxon’s internal reports, Exxon’s spokesman pointed to the peer-reviewed scientific research published by the company’s scientists between 1983 and 2014 – 53 papers in all.

Exxon scientists’ 100% global warming consensus

I reviewed all 53 of the papers referenced by Exxon’s spokesman, and they indeed consist of high-quality scientific research. Most of them implicitly or explicitly endorsed the expert consensus on human-caused global warming; none minimized or rejected it. This means that there is a 100% consensus on human-caused global warming among Exxon’s peer-reviewed climate science research – even higher than the 97% consensus in the rest of the peer-reviewed literature.

Of the 53 papers, 45 were co-authored by Haroon Kheshgi. I spoke to several climate scientists who worked with him and all agree, Kheshgi is a top-notch climate scientist, for example having constructively contributed to the first IPCC reports that identified a human influence on global warming. 

Katharine Hayhoe, one of TIME magazine’s 100 most influential people, did a summer internship with Kheshgi at one of Exxon’s facilities as part of her masters’ thesis research, and subsequently co-authored a number of papers with him. Hayhoe described her experience with Kheshgi and Exxon,

Haroon himself is an outstanding scientist - careful, detailed, methodical, and committed to doing good science, just as we all are. In my experience with Exxon and with Haroon, I never met a scientist who expressed any opinions counter to those prevalent in the academic community.

Much of Exxon’s early research in the 1980s dealt with climate modeling, for example projecting that the planet’s surface temperatures would warm 3–6°C above pre-industrial levels by the year 2100. Their research has often discussed the dangers associated with this degree of global warming, and many studies published by Exxon scientists investigated the possibility of mitigating climate change by sequestering carbon in the deep ocean.

The peer-reviewed research published by Exxon’s climate scientists was entirely in line with the expert consensus that humans are causing potentially dangerous global warming, and that we need to explore ways to mitigate the associated risks.

Exxon funded climate denial misinformation campaign

While Exxon’s own scientists and research were 100% aligned with the expert consensus on human-caused global warming, the company simultaneously funded a campaign to manufacture doubt about that scientific consensus. 

A new study published in the Proceedings of the National Academies of Science found that groups with funding from corporations like Exxon have been particularly effective at polarizing and misinforming the public on climate change. Since 1998, Exxon has given over $31 million to organizations and individuals blocking solutions to climate change and spreading misinformation to the public.

Exxon Knew

What #ExxonKnew vs what #ExxonDid. Illustration: John Cook,



2015 shatters the temperature record as global warming speeds back up

Posted on 18 November 2015 by dana1981 &

With just a month and a half left in 2015, it’s clear this year will be by far the hottest on record, easily beating the previous record set just last year. The temporary slowdown in the warming of global surface temperatures (alsomisnamed the “pause”) has ended, as each of the past four years has been hotter than the one before.

El Niño is one reason 2015 has been such an incredibly hot year. During El Niño events, hot water is transported from the deep ocean layers to the surface. Over the past 15 years, we’ve experienced more La Niñas than El Niños, which helped temporarily slow the warming of global surface temperatures.

That changed in 2015, which has seen the third-largest surface temperature warming influence from an El Niño event on record (behind 1998 and 1987). The chart below breaks down global surface temperature data into years with El Niño, La Niña, neutral, and volcanic eruption temperature influences. Click here for additional details and a larger version.

ENSO temps GIF

NOAA global surface temperature data (1966–2015) broken into El Niño (red), La Niña (blue), neutral (black), and volcanic eruption (orange) years with linear trends for each category. Created by Dana Nuccitelli.



Scientists warned the US president about global warming 50 years ago today

Posted on 5 November 2015 by dana1981 &

Fifty years ago today, as the American Association for the Advancement of Science highlighted, US president Lyndon Johnson’s science advisory committee sent him a report entitled Restoring the Quality of Our Environment. The introduction to the report noted:

Pollutants have altered on a global scale the carbon dioxide content of the air and the lead concentrations in ocean waters and human populations.

The report included a section on atmospheric carbon dioxide and climate change, written by prominent climate scientists Roger Revelle, Wallace Broecker, Charles Keeling, Harmon Craig, and J Smagorisnky. Reviewing the document today, one can’t help but be struck by how well these scientists understood the mechanisms of Earth’s climate change 50 years ago.

The report noted that within a few years, climate models would be able to reasonably project future global surface temperature changes. In 1974, one of its authors, Wallace Broecker did just that in a paper titled Climatic Change: Are We on the Brink of a Pronounced Global Warming?.

You can read the details about this paper and Broecker’s modeling here and in my book Climatology versus Pseudoscience. His model only included the effects of carbon dioxide and his best estimates of natural climate cycles. It didn’t include the warming effects of other greenhouse gases, or the cooling effects of human aerosol pollution, but fortunately for Broecker those two effects have roughly canceled each other out over the past 40 years.

Broecker’s model predicted the global warming anticipated by 2015 both from carbon pollution alone, and when including his best estimate of natural climate cycles. In the figure below, the carbon-caused warming is shown in blue, and in combination with natural cycles (which Broecker turns out not to have represented very accurately) in green, as compared to the observed global surface temperatures from NOAA in red. As you can see, the climate model predictions from over 40 years ago turned out to be remarkably accurate.

Broecker prediction

Wallace Broecker’s 1974 climate model global warming predictions vs NOAA observations. Created by Dana Nuccitelli.



Global warming could be more devastating for the economy than we thought

Posted on 27 October 2015 by dana1981 &

new study published in Nature by scientists at Stanford and UC Berkeley has made waves for its finding that thus far we have dramatically underestimated the damage human-caused climate change will do to the global economy.

By looking at data from 160 countries across the 50-year period from 1960 to 2010, the authors found that an average local temperature of 13°C (55°F) is economically optimal, particularly for agricultural productivity. That temperature roughly reflects the current climate in many wealthy countries like the USA, Japan, France, and China.

If regional temperatures are cooler, then warming benefits the local economy, but past that peak temperature, warming reduces economic productivity. The robustness of this result is particularly interesting. The study found that it held true for both rich and poor countries, and that the relationship held for both the 1960–1989 and 1990–2010 time frames.

Fig 1

Global relationship between annual average temperature and change in log gross domestic product (GDP) per capita during 1960–2010 with 90% confidence interval, broken down by poor and rich countries, agricultural and non-agricultural GDP, and time frames (1960–1989 and 1990–2010). Source: Burke et al. (2015), Nature.



Carbon pollution: the good, the bad, the ugly, and the denial

Posted on 21 October 2015 by dana1981 &

The anti-climate policy ‘fact blurring’ advocacy group Global Warming Policy Foundation (GWPF) recently published a report on ‘the good news’ about rising carbon dioxide, written by Indur Goklany. Goklany has a background in electrical engineering and has been a US delegate to the IPCC. He has also in the pastreceived $1,000 per month from the Heartland Institute and had two books published by the Cato Institute, among other affiliations with fossil fuel-funded think tanks.

Goklany’s affiliation with and funding from these think tanks is relevant due to the nature of the GWPF report, which essentially argues that carbon pollution is the best thing since sliced bread. 

The bad outweighs the good

Professor Colin Prentice, expert in climate change impacts on the biosphere at Imperial College London, put together a nice summary of what the report gets right and wrong. While the GWPF report is correct that there are some benefits from rising carbon dioxide levels, as Prentice notes,

The good news should not blind us to the negative implications of continued unabated climate change, and the multidecadal lead times required for policies to have any discernible effect on CO2 and climate. These are the reasons propelling international pressure for long-term carbon neutrality, and nothing that Goklany says in his report invalidates them.

In short, the report selectively considers only the evidence that supports its argument that carbon pollution is terrific. The report also argues against a strawman, portraying its opponents as claiming that there are no benefits associated with global warming. In reality, climate scientists and economists consider all climate change impacts, both good and bad, in their overall assessments. Unfortunately the bad consequences far outweigh the good, as even the GWPF’s own economic advisor Richard Tol has concluded. As climate scientist Richard Betts noted,

Assessments of the impacts of climate change on ecosystems and crops do include CO2 effects as well as physical climate effects, and while there are uncertainties in both, current understanding suggests that CO2 effects on photosynthesis will tail off while the impacts of climate change itself continue. The harms may well outweigh the benefits, especially when we remember that sea level rise is an inevitable consequence of a warming world. There are no good reasons to assume that that the effect of CO2 on plants is some sort of “get out of jail free” card.

‘CO2 is plant food’ is an oversimplification

The GWPF report mostly focuses on what’s sometimes called ‘global greening,’ associated with carbon dioxide fertilization of plants. It’s essentially the ‘CO2 is plant food’ oversimplification, tackled by Professor Sarah Green in the Denial101x lecture below.

 Sarah Green Denial101x lecture on climate change agricultural impacts.

In short, if all else is equal, higher carbon dioxide is generally better for plant growth. The problem is that when atmospheric carbon dioxide levels rise in the real world, we can’t hold everything else constant the way we can in a greenhouse. Temperatures rise, and the resulting extreme heat can have severely detrimental impacts on plant growth, particularly for certain crops like maize. That rise in temperatures also amplifies droughts, the increase of water vapor in the atmosphere intensifies floods, and so on.

To evaluate the impact of rising carbon dioxide and the associated climate changes on crop yields, all these factors need to be considered. While rising carbon dioxide may have benefited agricultural productivity so far, most studies project a decline in crop yields starting in 2030, and climate change poses many other dangerous risks, as summarized in the latest IPCC report.

IPCC crop yields

Summary of projected changes in crop yields, due to climate change over the 21st century. Source: IPCC Fifth Assessment Report, Working Group II.



Propaganda trumps journalism in conservative media climate reporting

Posted on 15 October 2015 by dana1981 &

Isoprene: it’s a gas that helps aerosols form in the atmosphere. It’s relevant to climate change because aerosols help clouds form, which can have cooling (by reflecting sunlight) or warming (by trapping heat) effects, depending on the type of cloud. Aerosols also cause cooling by directly scattering sunlight.

Past field measurements indicated that the oceans were releasing less isoprene than climate model simulations suggested they should. A new study found that previously unidentified reactions in the sea surface microlayer might represent a significant source of isoprene that could reconcile the discrepancy between measurements and models. In fact, climate models may even be underestimating the amount of isoprene released from the oceans.

Not relevant to global warming

What are the implications of this study for recent global temperature changes? As co-author Dr. Christian George told Carbon Brief,

Our study is a new brick that should help understanding our complex world, by providing new knowledge on air-sea exchanges, but it definitively does not question climate change, it just helps us understand its impact.

There is no question that the global climate will become warmer. The question is just how much, how fast and how the effects will change our lives.

Professor Piers Forster explained why suggestions that this study have significant climate change implications are wrong for several reasons. The primary reason is that changes in global temperature would only be caused by changes in natural isoprene emissions. As Forster noted,

The natural aerosol cooling could be 100 times bigger than our current estimate, but it would make no difference to climate change as it would stay more-or-less constant with time.

Marine isoprene releases could only cause global warming or cooling if the level of the emissions were to change. However, this paper merely suggests that the overall level of isoprene emissions is higher than previously thought, not that the levels are changing. And in fact the study indicates that climate model simulations might be more accurate on ocean isoprene emissions than previously believed.

Conservative media outlets choose propaganda over journalism

However, several conservative media outlets falsely claimed that the study had uncovered a “global cooling process.” Writing for Breitbart, James Delingpole claimed that the paper “may pose a serious threat to man-made global warming theory.” The Register and Express both claimed that temperatures have been stable for 15 years (they’ve actually risen by about 0.2°C during that time), and that this paper could explain that fictional temperature stability.

The problem lies in the fact that unlike Carbon Brief, whose reporters discussed the study and its implications with two climate scientists including one of the study authors, these conservative media outlets tried to interpret its meaning on their own. This led to mischaracterizations of the paper that Professor Forster described as “quite crazy.”

All of these conservative media pieces misrepresenting the paper shared another characteristic. Each revealed its bias by wishfully suggesting the international climate negotiations that will soon be held in Paris could be undermined by the study’s findings.

Rather than contact the study’s authors or any other climate scientists, the Express and Breitbart quoted Benny Peiser, a social anthropologist, climate fake expert, and director of the anti-climate policy Global Warming Policy Foundation (GWPF). The UK government’s Charity Commission ruled last year that the GWPF was blurring fact and comment on climate change, lacked neutrality, and promoted a contrarian position on the subject.

In essence, The Register, Express, and Breitbart seemed more interested in promoting a specific political cause – undermining efforts to implement climate policies – than in getting the facts right. And presenting misleading information to promote a political agenda is the very definition of propaganda.

Ironically, Delingpole accused Carbon Brief of being an “eco-propaganda website,” even though it was Carbon Brief that ensured factual accuracy by discussing the study and its implications with one of the study’s authors and a second climate scientist. Worse yet, Delingpole implied that Professor Forster is “stupid, dishonest, and semi-literate,” among other insults, for having the temerity to point out the factual inaccuracies in the Breitbart propaganda piece. This is the same James Delingpole who told Sir Paul Nurse in a climate conversation on BBC (a conversation in which Delingpole complained he was “intellectually raped”),

It is not my job to sit down and read peer-reviewed papers, because I simply haven’t got the time, I haven’t got scientific expertise. What I rely on is people who have got the time and expertise to do it … I am an interpreter of interpretations.

 Climate conversation between Sir Paul Nurse and James Delingpole on BBC.



The Republican Party stands alone in climate denial

Posted on 5 October 2015 by dana1981 &

A paper published in the journal Politics and Policy by Sondre Båtstrand at the University of Bergen in Norway compared the climate positions of conservative political parties around the world. Båtstrand examined the platforms or manifestos of the conservative parties from the USA, UK, Norway, Sweden, Spain, Canada, New Zealand, Australia, and Germany. He found that the US Republican Party stands alone in its rejection of the need to tackle climate change and efforts to become the party of climate supervillains.

Republicans would be fringe in any other country

As Jonathan Chait wrote of Republican presidential candidate Jeb Bush’s proposals to eliminate all significant American national climate policies,

In any other democracy in the world, a Jeb Bush would be an isolated loon, operating outside the major parties, perhaps carrying on at conferences with fellow cranks, but having no prospects of seeing his vision carried out in government. But the United States is different. Here in America, ideas like Bush’s fit comfortably within one of the two major political parties. Indeed, the greatest barrier to Bush claiming his party’s nomination is the quite possibly justified sense that he is too sober and moderate to suit the GOP.

So, what’s different about the United States? One factor is the immensely profitable and politically influential fossil fuel industry. However, Canada and Australia serve as useful analogues. With Australian coal reserves and Canadian tar sands, fossil fuels account for a larger share of both countries’ economies. Nevertheless, Båtstrand noted,

The [Republican] party seems to treat climate change as a non-issue ... this appears to be consistent with the U.S. national context as a country with large reserves of coal.



Is the fossil fuel industry, like the tobacco industry, guilty of racketeering?

Posted on 29 September 2015 by dana1981 &

ExxonMobil has become infamous for its secretive anti-climate science campaign, having spent $30 million funding groups denying the scientific evidence and consensus on human-caused global warming.

Last week, after an eight-month investigation, InsideClimate News revealed that from the late-1970s to the mid-1980s, scientists at Exxon were in fact at the cutting edge of climate science research.

Exxon documents show that top corporate managers were aware of their scientists’ early conclusions about carbon dioxide’s impact on the climate. They reveal that scientists warned management that policy changes to address climate change might affect profitability. After a decade of frank internal discussions on global warming and conducting unbiased studies on it, Exxon changed direction in 1989 and spent more than 20 years discrediting the research its own scientists had once confirmed.

In an internal September 1982 document, Exxon scientists summarized the expert consensus on human-caused global warming, and the consistency of their own research with that expert consensus.

The consensus is that a doubling of atmospheric CO2 from its pre-industrial revolution value would result in an average global temperature rise of (3.0 ± 1.5)°C … There is unanimous agreement in the scientific community that a temperature increase of this magnitude would bring about significant changes in the earth’s climate, including rainfall distribution and alterations in the biosphere … the results of our research are in accord with the scientific consensus on the effect of increased atmospheric CO2 on climate.

It’s ironic that 33 years ago, the world’s largest oil company accepted and concurred with the scientific consensus on human-caused global warming thatmany people continue to deny to this day.

In another internal company document in November 1982, Exxon scientists illustrated the rapid global warming they expected to occur over the following century due to rising carbon pollution from burning fossil fuels. A year earlier, Exxon scientists were discussing the distinct possibility that the consequences of climate change could become catastrophic in the near future.

exxon temp projections

Exxon’s 1982 projections of how human carbon pollution would cause global temperatures to rise.



Celebrated NASA planet hunter shifts his sights back to climate change on Earth

Posted on 24 September 2015 by dana1981 &

William Borucki has had an amazing scientific career. One of his first jobs was at NASA Ames Research Center, where he worked on the Apollo moon missions, including helping to develop the heat shield for the space shuttle. After the successful moon landings, Borucki shifted to NASA’s Theoretical Studies Branch in the 1970s, where he developed models of the Earth’s atmosphere to predict the effects of nitric oxides and chlorofluoromethanes on the ozone layer. Both were determined to contribute to the problem of ozone depletion and the hole in the ozone layer.

In the 1980s, Borucki began advocating the development of a space mission that could detect Earth-size planets. He published a paper in 1984 showing that a photometer 1,000 times more precise than any in existence could detect Earth-size planets. Undeterred by rejections of four proposals in the 1990s for a planet-finding mission, Borucki was ultimately appointed Principle Investigator in 2001 for NASA’s new Keppler Mission to discover these planets. During its four years of its operation, the Kepler Mission discovered over 4,600 planetary candidates, confirmed more than 1,000 as planets, and made numerous contributions to stellar astrophysics.

For his work in conceiving and leading the Kepler Mission, Borucki was awarded the Shaw Prize in astronomy. He decided to donate a portion of the award to the Union of Concerned Scientists (UCS) to support the organization’s work in addressing climate change, explaining,



Republicans are becoming the party of climate supervillains

Posted on 14 September 2015 by dana1981 &

As Politico recently reported in a news story that seems better suited for bad a Hollywood movie script, Republican Party leaders are actively trying to sabotage the critical international climate negotiations that will happen in Paris at the end of this year.

Top Republican lawmakers are planning a wide-ranging offensive — including outreach to foreign officials by Senate Majority Leader Mitch McConnell’s office — to undermine President Barack Obama’s hopes of reaching an international climate change agreement that would cement his environmental legacy.

Republican Party leaders have often argued that the United States shouldn’t take action to curb its carbon pollution unless China and other countries do as well.

Climate Desk mash-up of Republican leaders calling for China and other countries to cut their carbon pollution.

Now these countries are working to reach an international agreement in which all cut their carbon pollution, and Republican leaders are trying to undermine it. It’s as though they’re just looking for excuses to prevent the United States from reducing its fossil fuel consumption. As Jonathan Chait wrote,

In any case, the old conservative line, with its explicit or implicit promise that international agreement to reduce emissions might justify domestic emissions cuts, has suddenly become inoperative. The speed at which Republicans have changed from insisting other countries would never reduce their greenhouse-gas emissions to warning other countries not to do so — without a peep of protest from within the party or the conservative movement — says everything you need to know about the party’s stance on climate change.



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