Marlo Lewis

Post image for Gasoline or Ethanol: Which Is More Polluting?



Adding ethanol to gasoline makes it cleaner and reduces air pollution, right? So biofuel lobbyists would have us believe. However, a study published in Proceedings of the National Academy of Sciences (PNAS) comes to the opposite conclusion.

Lead author Jason Hill of the University of Minnesota Department of Bioproducts and Biosystem Engineering summarized key findings of the study at a recent House Science Committee hearing. To determine which is cleaner, gasoline or ethanol, researchers must “compare these fuels over their full life cycle.” Hill explains:

That is, we need to consider the damage caused by producing them in addition to using them. For gasoline, the life cycle includes extracting and refining crude oil, and distributing and combusting the gasoline itself. The life cycle of corn ethanol includes growing and fermenting grain, and distilling, distributing, and combusting the ethanol itself.

Although combustion emissions from ethanol are lower than those of gasoline, production emissions from ethanol are higher. So much so that on a life-cycle basis, ethanol is the larger source of five different air pollutants: primary fine particulate matter (PM2.5), nitrogen oxides (NOx), amonia (NH3), volatile organic compounds (VOCs), and sulfur oxides (SOx).

Ethanol vs Gasoline, Jason Hill, House Science, July 2015









Those results are an additional reason EPA should resist pressure from biofuel lobbyists to increase Renewable Fuel Standard (RFS2) blending targets for 2014-2016. As Hill cautions: [click to continue…]

Post image for EPA’s Power Sector Carbon Rules: Are They Legal?


EPA’s final “Carbon Pollution Standards” rule, released today, requires new coal-fired power plants to meet a standard of 1,400 pounds of carbon dioxide per megawatt hour (1,400 lbs. CO2/MWh) — less stringent than the 1,100 lbs. CO2/MWh standard in the agency’s Jan. 2014 proposed rule.

Under §111 of the Clean Air Act, performance standards are to reflect the “best system of emission reduction” (BSER) that has been “adequately demonstrated,” taking “cost” into account.

EPA says the final standard “better represents the requirement that the BSER be implementable at reasonable cost.” That’s a face-saving way of saying the agency’s original proposal would not have survived judicial review.

Although not as blatantly unreasonable, the rule remains fatally flawed. [click to continue…]

President Obama has not yet unveiled EPA’s final “Clean Power Plan” rule, but EPA has posted six so-called fact sheets. A few whoppers and rhetorical tricks in the preview “fact sheet” jump out at me.

Much of it is devoted to preaching the message that climate change endangers public health and welfare:

2014 was the hottest year in recorded history, and 14 of the 15 warmest years on record have all occurred in the first 15 years of this century. Recorded temperatures in the first half of 2015 were also warmer than normal. 

Not so fast. If 2014 was the warmest year, it was so by 0.02ºC — one-fifth of the 0.1ºC margin of error in surface temperature records. Accordingly, NOAA assigned 2014 a 48% probability of being the warmest year; NASA, a 38% probability.


Based on more reliable satellite data, 2014 was the 3rd or 6th warmest year in the record.

NASA NOAA Slide on UAH RSS Troposphere Temps

Besides, what really matters in assessing climate change risk is how fast the planet is warming compared to the forecasts on which scary-sounding climate impact scenarios are based. Here’s the big picture you won’t see in EPA’s “fact sheets”:

Christy Models vs Observations 1979 - Mar. 2015, Figure 1






In the latest (UAH V.6) version of the University of Alabama in Huntsville satellite record, the lower atmosphere warming rate of the past 36 years is 0.114ºC/decade — about the same rate the IPCC projects in its most aggressive emission-reduction scenario (RCP2.6). Is this a great atmosphere, or what?*

Christy UAH V. 6 Figure 3




[click to continue…]

Post image for Hearing Shines Light on Social Cost of Carbon Sophistry



Four witnesses testified on “the Obama administration’s Social Cost of Carbon” at a House Resources Committee hearing last week. Today’s post highlights key points from the testimonies of Cato Institute scientist Patrick Michaels and Heritage Foundation economist Kevin Dayaratna.

SCC Basics

First some background. The social cost of carbon (SCC) is the present discounted value of cumulative damages allegedly inflicted on society by an incremental metric ton of carbon dioxide (CO2) emissions over a period of decades to centuries.

Discernible in neither meteorological nor economic data, carbon’s social cost exists in the virtual world of “integrated assessment models” (IAMs) — computer programs that combine speculative climatology with speculative economics. By fidding with non-validated climate parameters, made-up damage functions, and below-market discount rates, SCC analysts can get almost any result they desire.

What they typically desire is to make fossil fuels look unaffordable no matter how cheap, and renewables look like a bargain at any price. However curious as an academic exercise, when used to make or influence public policy, SCC analysis is computer-aided sophistry.

The Obama administration’s Interagency Working Group (IWG) on the social cost of carbon uses three IAMs — DICEFUND, and PAGE — to estimate SCC values. EPA and the Department of Energy routinely incorporate SCC estimates into the cost-benefit analyses they use to justify their regulatory proposals. The White House now requires all federal agencies to incorporate SCC estimates in environmental impact reviews under the National Environmental Policy Act (NEPA).

Agencies have an incentive to periodically increase SCC estimates to make their regulations look more beneficial. For example, the IWG’s 2013 technical support document (TSD) increased the SCC values of the group’s 2010 TSD by roughly 60%.

In other words, in just four short years, climate change somehow got 60% worse and CO2 reductions 60% more valuable. Yet during that period, climate models increasingly overestimated global warming, and multiple datasets still showed no clear link between climate change and the frequency and strength of storms, droughts, and floods. Your tax dollars at work!

Earlier this month, the IWG published its response to comments (RTC) on the 2013 TSD. The IWG made minor technical corrections in how it runs the DICE and PAGE models but did not accept any of the substantive corrections recommended in 150 significant comment letters.

With that as context, let’s turn to the testimonies. [click to continue…]

Post image for EPA’s Climate Action Flimflam Report, Part 2


As explained previously on this blog, EPA’s report on the U.S. domestic benefits of aggressive “global action” to combat climate change is flamflam.

To recap, EPA estimates that by 2100, unchecked global warming will kill 57,000 Americans by intensifying air pollution and 12,000 Americans by intensifying heat waves. The agency also claims “significant global action” to limit future warming to 3.6ºF (2ºC) would avert those deaths.

EPA’s ‘methodology’ is GIGO from top to bottom.

To begin with, EPA assumes unchecked warming will add 9ºF to average global temperatures by 2100. That implies a warming rate of 1.058ºF/decade during the next 85 years. The actual warming rate over the past 36 years is 0.205ºF (0.114ºC)/decade, according to the latest University of Alabama in Hunstville (UAH) satellite dataset — less than one-fifth the rate in EPA’s projection.

EPA then models the impact of that implausible 9ºF warming on current U.S. air pollutant emissions, even though emissions and concentrations have declined, decade-by-decade, since 1980. All significant domestic air pollution sources will likely be gone long before 2100.

As for heat-related mortality, EPA bizarrely assumes that in 2100, 49 major U.S. cities either have the same adaptive capabilities they do today (12,000 fatalities), or at best have the adaptive capabilities of present-day Dallas (6,500 fatalities). Yet Centers for Disease Control data indicate that heat stress currently kills fewer than 650 Americans per year, and heat-related mortality rates in U.S. cities have declined, decade-by-decade since the 1960s. The most reasonable expectation is that such progress will continue.

Today’s post takes another look at EPA’s 9ºF warming projection. Turns out, EPA’s so-called business-as-usual scenario is actually a high-end emissions scenario. [click to continue…]

Post image for Dueling Opinion Polls: Is Climate Change the Top Global Concern — or Lowest?


A Pew Research Center survey of 45,435 respondents finds that “publics in 19 of 40 nations surveyed cite climate change as their biggest worry, making it the most widespread concern of any issue included in the survey.” Climate change ranks particularly high “in Latin America and Africa, where majorities in most countries say they are very concerned about this issue.”

Pew Survey Global Concerns July 2015








The survey, conducted during March 25-May 27, asks respondents whether they are “very concerned,” “somewhat concerned,” “not too concerned,” or “not at all concerned” about climate change, global economic instability, the Islamic Militant Group in Iraq and Syria (ISIS), Iran’s nuclear program, Cyber attacks on governments, banks, or corporations, Tensions between Russia and its neighbors, and Territorial disputes between China and its neighbors.

But this just in, reported Friday on WattsUpWithThat. The United Nations “My World” Initiative, a global survey of citizens from all countries with votes totaling 7,679,273, finds that climate change “is dead last in the list of concerns queried.” [click to continue…]

Post image for Is Carbon Capture and Storage a ‘System of Emission Reduction’?



Picture in your mind a house of cards or a row of dominoes. Pull out the base card and the structure collapses. Knock over the first domino and the rest fall down. Either image is a suitable metaphor for President Obama’s climate policy agenda.

EPA’s so-called Carbon Pollution Standards rule for new fossil-fuel power plants is the first domino in the row, the base of a multi-tiered greenhouse of cards.

The rule would establish “partial” carbon capture and storage (CCS) as the “adequately-demonstrated” (commercially-viable) “best system of emission reduction” (BSER) for new coal-fired power plants.

The jerry-built logic works like this.

  1. The Carbon Pollution rule is the legal prerequisite for EPA’s carbon dioxide (CO2) performance standards for existing power plants, the so-called Clean Power Plan.
  2. The Clean Power Plan, in turn, is the core component of the President’s emission-reduction pledge — the U.S. Government’s “Intended Nationally Determined Contribution” or INDC — in UN-sponsored negotiations aimed at adopting a new climate treaty at the December COP 21 conference in Paris.
  3. Finally, the President hopes the new climate pact, which he will not submit to the Senate for a vote on ratification, will focus international pressure on the next president and Congress to honor the U.S. INDC, thereby locking in the Carbon Pollution and Clean Power rules as legacy policies.

Each link in the chain has severe structural weaknesses. Using a non-ratified treaty to dictate U.S. domestic policy raises profound separation of powers concerns. The Clean Power Plan is unlawful on at least 10 separate counts. Evidence mounts that CCS technology is not adequately demonstrated because it is unaffordable absent lavish subsidies — hence the Carbon Pollution rule would not survive judicial review.

The point I want to emphasize in today’s post is that in actual commercial practice, CCS would increase net CO2 emissions. Thus what EPA is proposing is not even a system of emission reduction, much less the “best system of emission reduction” required by the Clean Air Act. [click to continue…]

Post image for Climate Change and Health: What Does the Gray Lady Say?


In a recent article, New York Times reporter Sabrina Tavernise asks: “Is climate change a serious threat to human health?” To my surprise, this was not a rhetorical question but the opener for an inquiry assessing the balance of evidence.

Tavernise even suggests that a recent White House report exaggerates climate change health effects to “build support” for the President’s domestic and international climate policy agenda.

As summarized by Tavernise, the report predicts that “Asthma will worsen, heat-related deaths will rise, and the number and traveling range of insects carrying diseases once confined to the tropics will increase.” But, she comments, those “bullet points convey a certainty that many scientists say does not yet exist.”

For one thing, some health effects attributed to climate change may actually be due to social factors:

For example, scientists note that global travel and trade, not climate change, brought the first cases of chikungunya, a mosquito-borne tropical disease, to Florida.

Sometimes even when climate change may affect health, it is difficult to quantify how important a factor it is. For example, Lyme disease is spreading into Canada — a development apparently linked to climate change because warmer weather lengthens tick breeding seasons. “But,” Tavernise points out, “Lyme disease is also an example of just how difficult it is to draw broad conclusions about how climate change affects health.”

The disease is also moving south, with large sections of Virginia and parts of North Carolina now inundated with ticks that carry the disease. But that pattern appears to have little to do with climate.

Dr. C. Ben Beard, associate director for climate change at the Centers for Disease Control and Prevention, said reforestation in the eastern United States and the expanding populations of deer and people appear to be factors.

What’s more, wealth and technology can greatly diminish climate-related health risks:

A study comparing Laredo, Tex., and a city just across the border in Mexico found the incidence of dengue fever was far higher in Mexico, even though the mosquitoes that carry it were more abundant in Texas. Researchers attributed the Texan advantage to economics — air conditioning and windows that shut — not climate.

Tavernise also notes that, despite global warming, heat-related deaths in the United States are not increasing:

Temperatures may be rising, but overall deaths from heat are not, in part because the march of progress has helped people adapt — air conditioning is more ubiquitous, for example, and the treatment of heart disease, a major risk for heat-related mortality, has improved.

In fact, U.S. heat mortality risk is declining:

A recent review of heat mortality in the United States found that the rate of heat-related deaths declined by more than half from 1987 to 2005. (For more on this topic, see these previous posts.)

Tavernise even seems to recognize some additional warming may have net health benefits because far more people die from extreme cold than extreme heat:

A study in The Lancet in May analyzed 74 million deaths from 1985 to 2012 in more than 10 countries, including the United States, and found that about 8 percent of the deaths had been caused by abnormal temperatures. Of those, the rate of death from cold — more than 7 percent — far outnumbered that from heat, about 0.42 percent. [click to continue…]

Post image for If You Only Read One Commentary on the Papal Encyclical . . .


The recent Papal Encyclical on “care of our common home” calls for “changes of lifestyle, production and consumption, in order to combat [global] warming,” and drastic reductions in greenhouse gas emissions, based on the assessment that fossil-fueled economies are “unsustainable” and “can only precipitate catastrophes.”

If that assessment were correct, population would be smaller today, and worse off, than in previous decades and centuries. The exact opposite is the case, observes economist Indur Goklany in a concise, by-the-numbers, rebuttal. The world’s population “is at a record level,” and human well-being “is at or near its peak by virtually every objective broad measure.”

The chart below shows a strong long-term correlation between carbon dioxide (CO2) emissions and increases in population, life expectancy, and per capita income — the best overall indicators of human health and well-being.

Goklany Population Income Life Expectancy Carbon Emissions July 2015





Those correlations are causal, not accidental.

The improvements in human well-being have been enabled directly or indirectly through the use of fossil fuels or fossil-fuel powered technologies and economic growth. This is because every human activity — whether it is growing crops, cooking food, building a home, making and transporting goods, delivering services, using electrical equipment for any purpose, studying under a light or going on holiday — depends directly or indirectly on the availability of energy (see below) and, in today’s world, energy is virtually synonymous with fossil fuels; they supply 82% of global energy used. [click to continue…]

Post image for PNAS Study Implicitly Confirms Climate Treaty Threatens Developing Country Economies


A study published this week in Proceedings of the National Academy of Sciences (PNAS) frets that the “carbonization” of energy resulting from the “renaissance of coal” in developing countries could render “ambitious” emission stabilization goals “infeasible.” Gee, really — who’da thunk it?

Although the main takeaway conclusion is obvious, the study provides lots of information about the factors (population, GDP per capita, energy intensity of GDP, carbon intensity of energy) driving global and regional emission trends.

As illustrated in the chart below, the big drivers of emissions growth, especially in recent years, are increases in GDP per capita, primary energy consumption, and the carbon intensity of energy. Population growth is not a significant factor. Decreasing energy intensity of production has worked to restrain emissions growth.

Kaya identity factors 1971 to present









The authors recognize that coal consumption in developing countries is strongly correlated with high rates of economic growth. Moreover, they find that the upsurge in consumption since 2000 is due to coal’s competitive price in global markets rather than domestic resource availability.

In summary, in recent years non-OECD countries have relied increasingly on coal to meet their energy needs. The poorer a country is and the higher its rate of economic growth, the stronger is this effect. Both effects become more pronounced over time, suggesting that increasing coal use is a general trend among poor, fast-growing countries and is not restricted to a few specific countries. These results confirm the hypothesis of a global renaissance of coal. This conclusion is strengthened by the fact that excluding China and India from the regression hardly affects the results (see SI Appendix for details), indicating that these two countries are not driving the results but rather are representative for the global sample. . . .This renaissance of coal has even accelerated in the last decade; this acceleration can be explained by the low prices of coal relative to other energy sources.

PNAS undoubtedly published the study because the results spell danger for the COP 21 climate treaty conference in Paris. In the authors’ words:

Our results raise the more general question of the role of developing countries in climate-change mitigation. Developing economies now account for such a large share of global energy use that the trend toward higher carbon intensity in these countries cancels out the effect of decreasing carbon intensities in industrialized countries. If the future economic convergence of poor countries is fueled to a major extent by coal, i.e., if current trends continue, ambitious mitigation targets likely will become infeasible.

The same conclusion implies, of course, that ambitious stabilization goals could make developing country efforts to eradicate poverty infeasible. Isn’t that the more important concern and issue? [click to continue…]