In An Inconvenient Truth (pp. 280-281), Al Gore enthused about a Science magazine study by Princeton economists Robert Socolow and Stephen Pacala. The study concluded that, “Humanity already possesses the fundamental scientific, technical, and industrial know how to solve the carbon and climate problems for the next half century.” Gore claimed the policies Socolow and Pacala recommend, “all of which are based on already-existing, affordable technologies,” could reduce emissions below 1970s levels.

But Gore could not know the solutions are “affordable,” because the authors did not attempt to estimate costs. The study basically shows that if political leaders can somehow coerce everybody to use less energy and adopt low- or zero-carbon energy technologies regardless of cost, they can significantly reduce emissions by 2054. We needed Princeton professors to tell us that?

If An Inconvenient Truth were a balanced presentation rather than a CGI-embellished lawyer’s brief, Gore would have mentioned that Socolow and Pacala’s (S&P) study was a response to an earlier analysis, also published in Science, by New York University Prof. Martin Hoffert and 17 colleagues.

Hoffert et al. found that all existing energy technologies “have severe deficiencies that limit their ability to stabilize global climate.” They specificially took issue with the UN IPCC’s claim that “known technological options” could stabilize atmospheric carbon dioxide (CO2) levels at 550 parts per million (ppm) or even 450 ppm over the next 100 years. Noting that world energy demand could triple by 2050, they found that zero-carbon technologies that can produce 100 to 300% of present world power consumption “do not exist operationally or as pilot plants.” Bottom line: “CO2 is a combustion byproduct vital to how civilization is powered; it cannot be regulated away.” They concluded that it is not possible to stabilize atmospheric CO2 concentrations and meet global energy needs “without drastic technological breakthroughs.”

I review this ancient history because Environmental Research Letters just published a study ‘updating’ (i.e. rebutting) the S&P analysis. The lead author is UC Irvine Prof. Steven Davis. One of three other co-authors is Martin Hoffert.

S&P estimated that seven ”stabilization wedges” could limit atmospheric CO2 concentrations to 500 ppm by 2054. The Davis team estimates it will take 19 and possibly 31 wedges to solve the climate ‘problem.’ In other words, the challenge is much more difficult than S&P believed.

But what, you may be wondering, is a “stabilization wedge”?

S&P depicted mankind’s emission trajectory on a graph. They estimated that if emissions could be held constant at 2004 levels, then atmospheric concentrations could be stabilized at 500 ppm in 2054. The area on the graph representing the growing gap between 2004 emissions and the projected increase in emissions over the next 50 years forms a triangle. S&P divide the triangle into seven wedges, each representing 1 gigaton of carbon (1 GtC) emissions in 2054 and 25 GtC in cumulative emissions over 50 years. Mankind could solve the climate ‘problem,’ S&P reasoned, by scaling up seven low- and zero-carbon technologies to the point where each avoids a cumulative 25 GtC by 2054.

Easier said than done! One of S&P’s strategies to achieve a stabilization wedge is to add double the current global nuclear capacity to replace coal-based electricity. However, although once predicted to be “too cheap to meter,” nuclear power is still not viable without subsidies and is not competitive with gas-fired electricity. The environmental movement, moreover, remains staunchly “no nukes,” and is unlikely to rethink its ideology in the post-Fukushima political climate.

Another strategy is to deploy carbon capture and storage (CCS) technology at coal power plants. Despite billions of dollars in government R&D support, no commercial-scale CCS coal power plant has been built. None today could operate without hefty subsidies. If hit with a carbon tax or a CO2 emissions standard, most utilities would find it cheaper to build new natural gas power plants than to build new coal plants with CCS.

A third S&P strategy is to increase wind capacity by 50 times relative to the mid-2000s, for a total of 2 million large windmills. The word boondoggle leaps to mind. If wind energy is such a great buy for consumers, why do 29 states have to mandate it? If it’s truly ’sustainable,’ why did the American Wind Energy Association (AWEA) assert that, despite enjoying government-guaranteed markets in more than half the states, the industry would crash unless Congress ponied up another $12.1 billion in special tax breaks?

Another strategy is to increase ethanol production 50 times. Subsequent research indicates that land conversions induced by ethanol production emit more CO2 than the petroleum displaced by ethanol consumption. Besides, even if ethanol were a low-carbon fuel, the scale up proposed – biomass plantations covering “an area equal to about one-sixth of the world’s cropland” – would intensify the already perilous fuel vs. food tradeoff and decimate millions of acres of forest and other wildlife habitat.

In the new study, “Rethinking Wedges,” Davis et al. note that since S&P was published in 2004, ”annual emissions have increased and their growth rate has accelerated, so that more than seven wedges would now be necessary to stabilize emissions.” More importantly, stabilizing emissions at current levels for 50 years would not be enough to limit CO2 concentrations to 500 ppm and, thus, avoid ‘dangerous anthropogenic interference,’ defined by climate negotiators as a warming of 2°C or more.*

So what would “solve the carbon and climate problem,” according to Davis et al.? You guessed it — “sharply reducing CO2 emissions over the next 50 years,” indeed, deploying enough wedges to achieve “near-zero emissions.” They estimate:

Given the current emissions trajectory, eliminating emissions over 50 years would require 19 wedges: 9 to stabilize emissions and an additional 10 to completely phase-out emissions. And if historical, background rates of decarbonization falter, 12 ‘hidden’ wedges will also be necessary, bringing the total to a staggering 31 wedges.

Figure explanation (from Davis et al. 2013): Idealization of future CO2 emissions under the business-as-usual SRES A2 marker scenario. Future emissions are divided into hidden (sometimes called ‘virtual’) wedges (brown) of emissions avoided by expected decreases in the carbon intensity of GDP by ~1% per year, stabilization wedges (green) of emissions avoided through mitigation efforts that hold emissions constant at 9.8 GtC y beginning in 2010, phase-out wedges (purple) of emissions avoided through complete transition of technologies and practices that emit CO2 to the atmosphere to ones that do not, and allowed emissions (blue). Wedges expand linearly from 0 to 1 GtC y from 2010 to 2060. The total avoided emissions per wedge is 25 GtC, such that altogether the hidden, stabilization and phase-out wedges represent 775 GtC of cumulative emissions.

What it means is that you can’t get there from here without fundamental technology breakthroughs — exactly what Hoffert et al. concluded in 2002. Over the next four decades the world will need multiple terawatts (trillions of watts) of new energy. None of the existing zero-carbon energies is up to the challenge:

CCS has not yet been commercially deployed at any centralized power plant; the existing nuclear industry, based on reactor designs more than a half-century old and facing renewed public concerns of safety, is in a period of retrenchment, not expansion; and existing solar, wind, biomass, and energy storage systems are not yet mature enough to provide affordable baseload power at terawatt scale. Each of these technologies must be further developed if they are to be deployed at scale and at costs competitive with fossil energy.

Filling up 31 wedges will require “deploying tens of terawatts of carbon-free energy in the next few decades.” That will entail “a fundamental and disruptive overhaul of the global energy system.” In short, “Current technologies and systems cannot provide the amounts of carbon-free energy needed soon enough or affordably enough to achieve this transformation.”

Davis et al. recommend an “aggressive set of policies” to “support energy technology innovation across all stages of research, development, demonstration, and commercialization.”

But if existing zero-carbon technologies cannot affordably be scaled up to meet current and projected global energy needs, how likely is it that technologies either not yet invented or as yet prohibitively expensive can affordably replace the world’s fossil-fuel infrastructure? And aren’t there significant risks to public health and welfare from policies “aggressive” enough to implement a “disruptive overhaul” of the energy infrastructure that supports the lives and livelihoods of billions of human beings? Rethinking Wedges is a mix of realism and wishful thinking, environmental precaution and regulatory recklessness.

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

* Here Davis et al. follow the self-anointed ‘scientific consensus.’ For an alternative assessment of climate sensitivity (how much warming results from a given increase in CO2 concentrations), see Chip Knappenberger’s Lower Climate Sensitivity Estimates: Good News, Another Lower Climate Sensitivity Estimate (with Pat Michaels), and Climate Sensitivity Going Down. For an alternative assessment of climate change impacts, see Indur Goklany’s Trapped Between the Falling Sky and the Rising Seas: The Imagined Terrors of the Impacts of Climate Change.

No — or, more precisely, not  yet — conclude R.M. Hirsch and K.R. Ryberg of the U.S. Geological Survey in a recent study published in Hydrological Sciences Journal.

“One of the anticipated hydrological impacts of increases in greenhouse gas concentrations in the atmosphere is an increase in the magnitude of floods,” note Hirsch and Ryberg. Righto! Google “global warming” and “flood predictions,” and you’ll find more than 2.7 million sites where this hypothesis is affirmed or at least discussed. The researchers explain:

Greenhouse gases change the energy balance of the atmosphere and lead to atmospheric warming, which increases the water-holding capacity of the atmosphere, which in turn, potentially changes the amount of precipitable water.

Sounds plausible, but all weather is local or regional, and a lot more goes into making weather than average global temperature.  In addition, all flooding is local or regional, and a lot more goes into determining flood risk than local or regional weather patterns.

As Hirsch and Ryberg point out, “human influences associated with large numbers of very small impoundments and changes in land use also could play a role in changing flood magnitude,” and “at time scales on the order of a century it is difficult to make a quantitative assessment of the changes in these factors over time.”

That, however, did not stop good ol’ Al Gore from claiming that global warming is responsible for a decade-by-decade increase in the number of large floods around the world (An Inconvenient Truth, p. 106). Gore’s source was a chart from the Millennium Ecosystem Assessment (Figure 16.5, p. 448):

The chart does appear to show significant decadal increases in the number of floods. However, what the chart actually measures is the number of “damaging” floods, and whether or not a flood is classified as “damaging” is influenced by socio-economic and even political factors. As the MEA report explains:

Only events that are classified as disasters are reported in this database. (An event is classified as a disaster if it meets at least one of the following criteria: 10 or more people reported killed; 100 or more people reported affected; international assistance was called; or a state of emergency was declared . . .

Obviously, the database is going to be skewed towards more events in later decades simply because of better reporting, more declared states of emergency, and more calls for international assistance. As the MEA report observes, “although the number has been increasing, the actual reporting and recording of floods have also increased since 1940, due to the improvements in telecommunications and improved coverage of global information.”

The MEA report also identifies several non-climatic factors that influence flood damage risk: wetlands loss and deforestation, changes in engineering practices, irrigation, urbanization, and, perhaps most importantly, population growth and economic development in flood plains.

In short, teasing out a greenhouse warming “signal” from flood damages influenced by both natural climate variability and a host of societal factors is a daunting task. Yet Gore treats flood damage data as unambiguous evidence of a warming-ravaged planet.

Okay, let’s get back to the USGS scientists. Hirsch and Ryberg acknowledge they cannot entirely filter out “reservoir storage, urban development, or other human activities in the watersheds” without narrowing their study “almost entirely to very small watersheds, typically in remote and often mountainous areas.” As a reasonable compromise, they examined flood data from “200 streamgauges operated by the US Geological Survey (USGS) in the coterminous USA, of at least 85 years length through water year 2008, from basins with little or no reservoir storage or urban development (less than 150 persons per square kilometre in 2000).”

What did they find? From the paper’s abstract:

In none of the four regions [Northeast, Southeast, Northwest, Southwest] defined in this study is there strong statistical evidence for flood magnitudes increasing with increasing GMCO2 [global mean carbon dioxide concentration]. One region, the southwest, shows a statistically significant negative relationship between GMOC2 and flood magnitudes.

For further reading, the Center for the Study of Carbon Dioxide and Global Change summarizes the results of 21 peer-reviewed studies on flooding and climate variability in North America. The Center concludes:

Taken together, the research described in this Summary suggests that, if anything, North American flooding tends to become both less frequent and less severe when the planet warms, although there have been some exceptions to this general rule.  Hence, although there could also be exceptions to this rule in the case of future warming, on average, we would expect that any further warming of the globe would tend to further reduce both the frequency and severity of flooding in North America, which, of course, is just the opposite of what the world’s climate alarmists continue to claim would occur.

Last month, the Bureau of Ocean Energy Management, Regulation, and Enforcement (BOEMRE) suspended wildlife biologist Charles Monnett, who is being investigated by the Department of Interior’s (DOI’s) inspector general (IG). Monnett is the lead author of a 2006 study (linking loss of Arctic sea ice to the first documented finding of drowned polar bears.  The paper helped galvanize support for DOI’s listing of the bear as a threatened species under the Endangered Species Act. Al Gore touted the study in An Inconvenient Truth.

Public Employees for Environmental Responsibility (PEER) condemned the IG investigation as a “witch hunt” (Greenwire, Aug. 10, 2011, subscription required). Last week, the Center for Biological Diversity (CBD) and Greenpeace sent a letter to DOI Secretary Ken Salazar accusing BOEMRE of trying to muzzle scientists whose research may impede the granting of permits to drill for oil and gas in the bear’s Arctic habitat.

The transcript of the IG’s February 23, 2011 interrogation of Monnett shows that the IG “sent agents with no scientific training to ask decidedly unscientific questions about bizarre allegations relating to the polar bear paper,” CBD and Greenpeace contend. I can’t help but agree. What’s going on?

DOI officials say the investigation has nothing to do with drilling permits or the scientific integrity of Monnett’s research. As Greenwire reported last week:

BOEMRE spokeswoman Melissa Schwartz in an email said that the investigation has nothing to do with drilling. “There is absolutely no connection between any aspect of our review and approval of Shell’s Exploration Plan and Dr. Charles Monnett,” she said. “As we stated last week, the agency placed Dr. Monnett on administrative leave for reasons having nothing to do with scientific integrity, his 2006 journal article, or issues related to permitting. Any suggestions or speculation to the contrary are wrong.”

According to yesterday’s Greenwire, “a leaked memo to Monnett from the IG referenced possible procurement violations related to an ongoing study at the University of Alberta called Populations and Source of Recruitment in Polar Bears: Movement Ecology in the Beaufort Sea.”

But during the Feb. 23 interrogation, the IG agents do not discuss procurement issues. Rather, they claim to be investigating “allegations of scientific misconduct,” which one agent describes as “basically, uh, wrong numbers, uh miscalculations” (p. 83). Most of the questions relate to the polar bear study — the Monnett team’s observational M.O., their data, and assumptions.

I see no signs of scientific misconduct in Monnett’s study, and the Feb. 23 interview brought none to light. Monnett and his team observed four drowned bears after an abrupt wind storm, three within the “transect” surveyed by their aircraft. Since the transect covers one-nineth (11%) of the total study area (640 square kilometers), the team concluded it is “likely that many other bears also drowned but were not seen.” How many? Well, 9 x 3 = 27.

This is the source of Al Gore’s claim, in An Inconvenient Truth (p. 146), that “A new scientific study shows that, for the first time, polar bears have been drowning in significant numbers.” Gore, naturally, indulges in rhetorical license. ”Shows” suggests empirical proof. Monnett’s team made clear that a “likely” body count of 27 drowned bears depends on the assumption that the transect they surveyed was typical of the larger study area. “Have been drowning” suggests an ongoing process. Monnett’s team observed four drowned bears on one day in September 2004. 

Surely it was inevitable that zealots like Gore would ignore the qualifications and exaggerate the certainity and magnitude of the drowning polar bear problem. Maybe Monnett hoped this would happen. Nonetheless, it is not scientific misconduct to present research that politicians and activists exploit for their own agendas. This was in fact the first recorded observation of drowned polar bears. It coincided with the biggest decline in polar sea ice coverage during the study period (1979-2004). It was worth reporting in a scientific study, and scientists are supposed to draw properly caveated inferences from what they observe.

Could BOEMRE or DOI’s IG be a hotbed of climate change skeptics or a cabal of “drill baby drill” advocates out to punish Monnett for his influential polar bear study? I have no idea. This much is abundantly clear:

• The IG agents’ claim to be investigating “allegations of scientific misconduct” flatly contradicts the DOI spokesperson’s claim that the investigation has “nothing to do with scientific integrity.”
• The IG agents in the Feb. 23 interview bumble and stumble over basic algebra and utterly fail to reveal evidence of scientific misconduct.
• If the transcript is indicative of the larger IG investigation, we may infer that Monnett is “likely” a target of political harassment.
• If that proves to be the case, climate change skeptics, many of whom have been on the receiving end of threats and bullying, should roundly condemn the abuse.

Al Gore’s film An Inconvenient Truth bombarded audiences with image after image of hurricanes, tornadoes, floods, forest fires, and drought, creating the impression of a world in climate chaos. Gore blamed the alleged upsurge in extreme weather on global warming, that is, mankind’s sins of emission. One of Gore’s mighty pieces of evidence was a dramatic increase in insurance payments for weather-related damages. As he writes in his best-selling book of the same title:

Over the last three decades, insurance companies have seen a 15-fold increase in the amount of money paid to victims of extreme weather. Hurricanes, floods, drought, tornadoes, wildfires and other natural disasters have caused these losses [An Inconvenient Truth, p. 101].

Gore presented a chart similar to this one:

Seeing is believing, right? The problem, of course, is not merely that correlation (warmer weather/bigger losses) does not prove causation. More importantly, the economic data depicted in the chart have not been adjusted (“normalized”) to offset increases in population, wealth, and the consumer price index.

Consider this fact: More people today live in just two Florida counties, Dade and Broward, than lived in all 109 coastal counties from Texas to Virginia in 1930. Florida’s population grew by more than 17.5% in the past decade alone and today is 48% larger than in 1980. There’s tons more stuff in harm’s way than there used to be. No wonder damages are bigger than in the good old days!

Most studies that “normalize” economic loss data find no evidence of a trend towards more violent or destructive weather. Here, for example, is a chart from a study on normalized hurricane damages by Pielke, Jr et al. 2008:

Figure description: U.S. hurricane damages, 1900-2005, if all hurricane strikes had hit the same locations but with year 2005 population, wealth, and consumer price index.

A study published earlier this year in the Bulletin of the American Meteorological Society (Bouwer, L.M. 2011. Have disaster losses increased due to anthropogenic climate change?) examines 22 previous studies on the oft-asserted link between climate change and weather-related damages.

Here’s what the researcher, Laurens M. Bouwer of the Institute for Environmental Studies in the Netherlands, found:

All 22 studies show that increases in exposure and wealth are by far the most important drivers for growing disaster losses. Most studies show that disaster losses have remained constant after normalization, including losses from earthquakes (see Vranes and Pielke 2009). Studies that did find increases after normalization did not fully correct for wealth and population increases, or they identified other sources of exposure increases or vulnerability changes or changing environmental conditions. No study identified changes in extreme weather due to anthropogenic climate change as the main driver for any remaining trend.

Bouwer concludes:

The studies show no trends in losses, corrected for changes (increases) in population and capital at risk, that could be attributed to anthropogenic climate change. Therefore, it can be concluded that anthropogenic climate change so far has not had a significant impact on losses from natural disasters.

CO2Science.Org has an excellent review of the Bouwer study. On a related issue, World Climate Report reviews a recent study finding no long-term increase in the number of Atlantic tropical storms and hurricanes over the past 130 years. The apparent increase in storm frequency turns out to be an artifact of the data, that is, a product of the increase in spatial coverage and accuracy of hurricane monitoring systems.