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The Faustian Bargain

By Andrew Glikson
Created 12/01/2009 - 00:06

Dr Andrew Glikson [0]is an earth and paleo-climate research scientist at the Australian National University. This is his second article for Webdiary (the first was Dangerous climate change: Lessons from the recent history of the atmosphere [0]). References for this article can be found here [0].

THE FAUSTIAN BARGAIN
How a carbon-emitting atom-splitting species threatens to turn a planet into a radioactive
3 to 6 degrees c high sea level world

 

The sensitivity of the Earth’s atmosphere to anthropogenic carbon gases has been underestimated. As the orgy of burning carbon products of 400 million of biological evolution continues unabated, pushed by business, advertisers and consumption-promoting governments, global warming proceeds at a pace faster than projected by the IPCC (Houghton et al., 2001; Rahmstorf, 2007), tracking toward likely climate tipping points. The science fiction-like specter of global warming precludes many from discriminating between the climate and the weather. A well financed denial syndrome frustrates 11th hour attempts at mitigation. Governments, caught between the climate and fossil fuel interests, debate woefully inadequate carbon emission targets (Garnaut, 2008) unlikely to stabilize the rise of temperature, migration of climate zones, sea level and storm intensities (Anderson and Bowes, 2008). Politicians don’t get it, failing to understand they cannot argue with the atmosphere and the oceans. Only a global strategy aimed at immediate deep cuts of carbon gas emissions, innovation of technology for CO2-sequestration and down-draw to levels below 350 ppm (Hansen et al., 2008), albedo enhancement over polar regions and fast tracked reforestation campaigns may be capable of mitigating the worst consequences of runaway global warming. As times goes on, in an increasingly stressed world, the possibility of a nuclear conflagration of hair-trigger missile fleets, by accident or design, becomes a probability. Hapless populations are faced with a non-choice between a greenhouse summer and/or a nuclear winter. Will the powers to be, always willing to use $trillions to bomb peasants in remote corners of the globe (in the name of freedom and democracy), or rescue corrupt bankers, be willing to take all the measures needed to protect the young, future generations and nature?

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“The sleep of reason produces monsters”
Francisco Goya

 

The climate crisis

By contrast to the frozen surface of Mars (0.006 bar; -140oC to +20oC) and the greenhouse atmosphere of Venus (92 bars; 467oC), the Earth’s atmosphere (1 bar)) buffers a surface temperature range of -89oC to +57.7oC through the absorption/ emission effect of infrared radiation by greenhouse gas (GHG) molecules (H2O, CO2, CH4, N2O), allowing liquid water at the surface and thereby life. Had GHG been absent the Earth surface would have been several tens of degrees colder.

Primary energy sources of the atmosphere and oceans are derived from solar radiation, terrestrial heat flow, volcanism and hydrothermal activity, reinforced or mitigated by feedback effects from the hydrosphere, cryosphere and biosphere. These processes include changes in CO2 solubility in the oceans, drying or flourishing vegetation and the activity of animals. Ocean currents and winds controlled by temperature gradients, salinity and continent-ocean-mountain patterns redistribute the primary and feedback energy forcing effects. During glacial eras the polar continental ice sheets and sea ice provide powerful feedback effects through an increase or decrease in albedo and the exposure or closure of heat absorbing ocean surface areas. Clouds increase the albedo as well as act as a greenhouse warming medium. Short term rises in aerosols (volcanic eruptions, dust storms) affect the Earth’s albedo.

Since 1750 carbon emission from human industry and land clearing resulted in the rise of CO2 levels by ~38%, triggering atmospheric energy rise of +1.6 W/m2, methane levels by 150% (+0.45 W/m2), and N2O +0.15 W/m2 (IPCC, 2007), a rate of increase unrecorded in the recent history of Earth (Figs 1-4). The total energy rise of the climate system during 1961-2003 represents a near-3 fold acceleration of global warming. Increased evaporation due to surface warming results in higher atmospheric water vapor content and precipitation, often associated with cyclones, over tropical and subtropical zones.

By contrast mid-latitude zones are drying up due to polar-ward migration of climate zones by near-400 km (Hansen et al. 2007, 2008), the Murray-Darling being an example. Increased atmospheric CO2 levels result in ocean acidification due to an increase in the role of carbonic acid, decreasing the pH by 0.1, with effects on marine fauna and coral reefs such as the Great Barrier Reef.

Changes associated with the 20th century GHG rise include rise in solar insolation (+0.06 – 0.30 W/m2) during the first half of the 20th century (Solanki, 2002, 2004), albedo rise due to sulphur aerosols released by carbon burning (-0.5 W/m2), cloud formation (-0.7 W/m2) due to rising temperatures and land clearing (-0.2 W/m2).

The relation between GHG and temperature is calibrated by the parameter of Climate Sensitivity, estimated with a mean value of 3oC per doubling of CO2 levels. The rise of CO2 from 280 to 387 ppm since the 19th century corresponds to temperature rise of ~1.1oC, above the measured mean global temperature rise of ~0.8 oC, though carbon cycle feedbacks and ice melt-water interaction push this value further upward.

The critical role of CO2 and CH4 in governing past climates is demonstrated by correlations of palaeobotanical evidence (plant stomata pore density), glacial sediments and carbon mass balance calculations (Berner, 2004; Beerling and Berner, 2005; Royer, 2006; Royer et al., 2004, 2007; Ruddiman, 2003). Ice core records of the last 740,000 years leave little doubt regarding the role of CO2 and CH4 during the glacial-interglacial Milankovic cycles and Dansgaard-Oeschger (D-O) ~1470 years-long cycles (Ganopolski amd Rahmstorf, 2001) during the last ice age.

The emission of over 305 Gigatons of Carbon since the industrial revolution resulted in conditions not known since the last interglacial termination 124,000 years-ago and are tracking toward conditions analogous to the mid-Pliocene (~3.0 Ma) when CO2 levels reached ~400 ppm, temperatures rose by 2-3oC relative to the 20th century and sea level rose by 25+/-12 metres (Dowsett et al., 2005; Haywood et al., 2005; Zachos et al., 2001; Gingerich, 2006).

 

Figure 1. Northern hemisphere temperature reconstructions 700AD – 2008, based on multiple proxies (tree rings, coral reefs, pollen, cave deposits, ice cores, oxygen isotopes) compared with sunspot plot. (AR4-IPCC-2007 Fig. TS-20) correlated with the 1600 – 2000 sun spot activity plot of Solanki, 2002. Note (1) close correlation of the “little medieval winter” with low sun spot activity; (2) peak mid- 20th century sun spot activity (0.4 Watt/m2 higher than 1900); (3) decline in sun spot activity from the mid-20th century, decoupled from a rise of temperature anomalies by another 0.5oC).

Figure 2. Global temperature trends 1850 – 2008 (IPCC-2007-Fig. TS.6) and correlated sun spot radiative levels. (1) (Top) Patterns of linear global temperature trends over the period 1979 to 2005 estimated at the surface (left), and for the troposphere from satellite records (right). (2) Annual global mean temperatures (black dots) with linear fits to the data. The left hand axis shows temperature anomalies relative to the 1961 to 1990 average and the right hand axis shows estimated actual temperatures. Linear trends are shown for the last 25 (yellow), 50 (orange), 100 (purple) and 150 years (red). The smooth blue curve shows decadal variations. (3) Variations in the energy level of sun spot cycle (+/- 0.2 Watt/m2) during 1975 – 2008.

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Climate impasse developments through the late 20th century and the early 21st century include:

A. Atmospheric CO2 rates, rising to 2.2 ppm/yr in 2007, exceed 1850-1970 rates by factors of ~4 to 5, two orders of magnitude higher than mean CO2 rise rates of the last glacial termination (~0.014 ppm/yr).

B. A rise of mean global temperature of more than 0.8oC since 1850 and 0.6 oC since 1975-6. Mean temperature rise rates of 0.016C/year during 1970 - 2007 were about an order of magnitude faster than during 1850-1970 (0.0017C) and during the last glacial termination.

C. As indicated by paleotemperature studies (δ18O and δD - deuterium) studies of Greenland ice cores (Broecker, 2000; Braun et al., 2005) the atmosphere is amenable to abrupt climate changes and tipping points. Thus the last termination (14.7 – 11.7 kyr) displays extreme temperature changes on the scale of several degrees C in a few years (Steffensen et al., 2008) to decade scale (Alley, 2003; Kobashi et al., 2008), testifying to an extreme sensitivity of the atmosphere and the possibility of climate impasse tipping points (Fig. 5).

D. The rise of mean Arctic and sub-Arctic temperatures in 2005-2008 by near +4oC relative to mean 1951 – 1980 values (Fig. 4). Polar ice caps, commonly referred to as the “canary in the coal mine”, offer a sensitive parameter for global temperature changes, which they exceed by about a factor of X2.

E. Arctic Sea ice melt rates of ~5.4% per-decade since 1980, increasing to >10% per year during 2006-2007 (National Snow and Ice Data Centre [NSIDC], 2008) have surpassed the IPCC estimates.

F. West Antarctica warming and ice melt rates >10% per decade, culminating in mid-winter ice shelf breakdown (Wilkins ice shelf; June, 2008, NSIDC, 2008).

G. Advanced melt of the Greenland ice sheet of 0.6% per-year between 1979 and 2002 (Steffen and Huff, 2002; Frederick et al., 2006)

H. Slow-down of the North Atlantic thermohaline conveyor belt and down-welling water columns (NASA, 2004; Bryden et al., 2005), with attendant danger of its cessation analogous to conditions ~8.2 kyr ago (Alley et al., 1997, 2003).

I. Temperature projections for the North Atlantic Ocean (Keenlyside et al., 2008) may reflect the effect of Greenland ice melt waters, which may lead to transient cooling similar to events recorded in ice cores at ~12,900 – 11,700 (Steffensen et al., 2008) and ~8200 years-ago.

J. Increased frequency and intensification of categories 4 and 5 hurricanes (Webster et al., 2005). An overall increase in the intensity of extreme weather events, i.e. cyclones, floods and fires associated with high summer temperatures.

K. Mean sea level rise rate of ~0.32 cm/yr during 1988-2007 more than doubled relative to the mean ~0.14 cm/yr rate of 1973-1988 and three times those of 1850-1970 (Rahmstorf, 2006). In so far as doubling of sea level rise rates continues at this rate through the 21st century, they may approach rates similar to those of the last glacial termination (1.3 – 1.6 cm/yr) before mid-century, with sea level rise by several metres toward the end of the century as estimated by Hansen et al (2007).

L. Polar-ward migration of climate zones associated with the contraction of the Antarctic wind vortex, resulting in increase in temperature and decrease in rainfall in much of southern Australia, in particular the southwest and the southeast.

M. Increased frequency of the El-Nino events of the ENSO cycle, resulting in increased draughts in northeast Australia, India and parts of east Africa.

N. Methane (CH4), which after ~20 years has X23 times the greenhouse warming effect of CO2, rose by 10 ppb during 2007 (http://web.mit.edu/newsoffice /2008/techtalk53-7.pdf), exceeding the 1850-1970 rise rate (c. 5.4 ppb/yr) and orders of magnitude faster relative to the last glacial termination. Methane deposits vulnerable to small temperature rise reside in permafrost (~900 billion ton Carbon - GtC), high latitude peat lands (~400 GtC), tropical peat lands (~100 GtC), vegetation (~650 GtC) and methane hydrates and clathrates in the ocean and ocean floor sediments (> 16,000 GtC). These exceed the atmospheric level of carbon (~750 GtC), carbon emissions to date (~305 GtC) and known economic carbon reserves (>>4000 GtC). Elevated methane release from Arctic Sea sediments and sub-Arctic permafrost were recently recorded (Walter et al., 2006; Rigby, 2008).

Large scale release of methane is considered the trigger for the Paleocene-Eocene mass extinction at 55 Ma (Wing, 2003; Sluijs et al., 2007). Release of CO2 and methane associated with volcanic and impact events constituted a major factor associated with at least four of the five mass extinction of species, including the Permian-Triassic (~251 Ma), end-Triassic (~200 Ma), end-Jurassic (~145 Ma) and end-Cretaceous (~65 Ma) (Glikson, 2005, 2008).

Figure 3. Global mean radiative forcing since 1750 (AR4-2007 Fig. TS.5). Global mean radiative forcings (RF) and their 90% confidence intervals in 2005 for various agents and mechanisms. Columns on the right-hand side specify best estimates and confidence intervals (RF values); typical geographical extent of the forcing (Spatial scale); and level of scientific understanding (LOSU).

Figure 4. Global temperature anomalies in 2005, 2007 and 2008 in degrees C relative to 1951-1980 (Hansen et al., 2008)

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B. The denial syndrome

For the last 20 years or so, through numerous public presentations, articles published in economic and social journals (but rarely in the peer-reviewed scientific literature), extensive media exposure and intense political lobbying, so-called climate change “skeptics”, many of whom affiliated with right-wing groups and fossil fuel corporations, have attempted, continue to deny the reality of climate change, or interpret global warming in terms of natural processes, or claim it is beneficial.

Climate “skeptics”, more suitably referred to as denialists, attempt to advance their cause in two principal ways: (1) present outdated or imaginary technical arguments; (2) claim conspiracy on the part of climate science research organizations and climate scientists, to whom the often refer in derogatory ad-hominem terms.

Using terms such as “alarmism”, denialists do not appear to recognize the professional and ethical responsibility of scientists to alert society to dangers, whether of natural or anthropogenic origin, such as looming epidemics, ultraviolet and cosmic radiation, smoking-related cancer, ozone depletion or the climate impasse.

Many of the denialists have been supported by fossil fuel interests. On 4.11.2006, Bob Ward, Senior Manager, Policy Communication, British Royal Society, addressed to a major oil company, stating, among other: “… I am writing to express my disappointment at the inaccurate and misleading view of the science of climate change that these documents present .… leaves readers with such an inaccurate and misleading impression of the evidence on the causes of climate change that is documented in the scientific literature… My analysis indicates that (your company) provided more that $2.9 million to organizations in the United States which misinformed the public about climate change through their websites.

One example is the film “The Great Global Warming Swindle”, screened by the Australian Broadcasting Corporation on 12 July, and which does not display temperatures records since the 1980s onward, omitting the critical evidence for greenhouse-driven climate change during the last 30 years when temperatures rose by ~0.6oC whereas solar radiation oscillated at +/-0.2 Watt/m2.

Denialists repeatedly attack what they call “science by consensus”. However, science, a self-correcting method, advances by trial and error. A consensus emerges when most scientists become convinced by the evidence and arguments for a new theory. Dedicated scientists will keep accumulating evidence and advance arguments which, if convincing, will tilt the balance. However, had it not been for the peer reviewed scientific literature, science would have drowned in a flood of uncontrolled claims, some true and many false.

There is no evidence the denialists are conducting any climate change research. Instead, they are searching for errors, real or imaginary, in the work of climate scientists whose professional integrity they keep attacking. In this respect denialists may be compared with creationists who, for the particular end of denying the relation between humans and the primates, choose to dismiss Darwinian evolutionary theory as a whole.

But attempts at denial of the reality of the climate impasse have already resulted in a delay of efforts at mitigation by almost 20 years. In the words of Hamilton (2008): “But if … skeptics were successful in stopping policies to cut emissions and the IPCC projections turn out to be correct, then environmental catastrophe will follow and millions of people will die. Do they lose sleep over this? Do they worry about how their grandchildren will see them? Or are they so consumed by their crusade that they know they will never be proven wrong?

Most arguments made by climate change deniers can be shown to be false:

1. A common argument relates to historical and geological warm periods, suggesting the current global warming is of natural rather than anthropogenic origin. However, studies of historical temperatures based ice cores, tree rings, corals, pollen, cave deposits, sediments and other proxies (Fig. 1) indicate late 20th to early 21st century mean temperatures exceed those of the Medieval Warm Period (1000 – 1150AD) by 0.5oC. Another argument is that the current warming represents a recovery from the “little ice age” (1600 – 1700AD), a period related to a near-cessation of sun spot activity (Fig. 1). However, sunspot activity has peaked by the mid-20th century, whereas temperatures continue to rise by ~0.6oC.

2. References by denialists to past natural climate changes, including the Emian (124,000 years-ago) when temperatures exceeded 20thc century levels by ~1oC, or the mid-Pliocene (3 Ma) when temperatures were + 2 to 3oC higher, miss the point. It is no more warranted to artificially raise atmospheric temperatures than, for example, destroy the ozone layer or lower the pH of the ocean just because such changes have taken place in the past!

3. Denialists often attribute global warming to an increase in solar radiation. An increase in sunspot activity toward the mid-20th century is correlated with a rise in insolation by about 0.06 – 0.30 Watt/m2, with a mean of 0.12 Watt/m2, an order of magnitude lower than caused by GHG radiative forcing of ~1.6 Watt/m2 (Fig. 3). Concomitant rise in insolation, the effect of aerosols and rising GHG during ~1950 – 1975 partly masked the GHG effect, which is clearly decoupled from the solar effect from about 1975 (Fig. 2). Warming of the upper troposphere, cooling of the upper atmosphere (in part related to ozone depletion), surface warming during winters and nights are consistent with GHG effects rather than solar effects.

4. As it has been suggested cosmic ray activity helps nucleate low-level clouds (Svensmark, 2007), some denialists invoked low cosmic rays to account for global warming. As an inverse relation occurs between peak sun spot activity and cosmic ray activity, this implies an increase in solar radiation parallel with global warming, but such increase has not been recorded from the mid-20th century (Solanki, 2002, 2004). Claims of correlations between paleo-temperature variations based on δ18O and cosmic ray effects read from meteorites (Shaviv and Veizer, 2003) have been refuted by Rahmstorf et al. (2004), who showed the data have been de-trended.

5. In the absence of a common extraterrestrial cause, claims by some denialists as if Earth shares climate changes with Mars and Venus remain unsupported.

6. Another argument by denialists relates to an apparent lack of a top-tropospheric “hot spot” (TTHS) (Singer and Douglass, 2004), an expected consequence of global warming. However, the TTHS has been in fact identified (http://www.realclimate.org/index.php/archives/2008/05/tropical-tropopshere-ii/.)(see [1]http://www.abc.net.au/%20unleashed/stories/ [2] s2323407.htm).

7. A common argument by denialists is a concentration of climate measurements around cities and conurbations. This argument, which may have had some validity during the earliest days of measurements, is negated by the global distribution of ground measurements, weather balloon measurements and satellite-based measurements over the world’s continents, oceans and polar regions. Hansen et al. (2001) estimate the effect of urban heat sources at ~0.1oC (http://earthobservatory.nasa.gov/%20Features/ [3]GISS.Temperature/ printall.php)

8. Referring to annual to multi-annual mean temperature oscillations related to the ENSO cycle (El-Nino 1998, 2002, 2007; La-Nina 2000, 2003, 2006, 2008), denialists claim the Earth has been cooling since 2002. As shown by global temperature trends (Fig. 3) the decline in the mean rate of temperature rise during 2000 – 2007 relative to 1975 – 2000 correlates with the effects of lower sun spot activity, and in 2003 and 2006 with the La-Nina. In so far as ice sheet melting may result in retardation of the Gulf Stream, a lull in warming, or even cooling of the North Atlantic Ocean, may be expected as a stage in global climate impasse, possibly reflected by projection of Keenlyside et al. (2008). The critical manifestation of global warming comes from the poles, where mean temperatures have increased by up to 4oC.

9. Denialists often criticize computer models, betraying a misunderstanding of their nature which, as in other field in science, constitute tools used to test matches between direct measurements, calculations and intepretations. More than 20 independently developed climate models are consistent with directly observed trends when the effect of GHG forcing is included in the calculations.

10. Claims CO2 increases are beneficial as plant food overlook the drying/burning consequences of the extensive droughts associated with polar-ward migration of climate zones, in particular in mid-latitudes, as in the Murray-Darling Basin. Some crops which may grow faster under elevated temperature also need water, an increasingly scarce commodity in these latitudes. Where precipitation increases due to expansion of the tropics, it is often associated with devastating tropical cyclones. In so far as some agricultural advantages may arise in northern latitudes from thawing of sub-Arctic permafrost, they are more than negated by the release of methane from the permafrost as a powerful feedback effect of global warming. Rising sea levels threaten vast coastal, delta and low river agricultural zones, the habitat and granary for many hundreds of millions people in southeast and southern Asia, northwestern Europe and northeast America, with social and economic consequences which defy contemplation. Not least, ocean acidification and the decline of marine fauna, coral reefs and fisheries, threaten the demise of Earth’s marine environments and a major food source for humanity.

In so far as the scientific method depends on examination of evidence from a range of perspectives, those who describe themselves as climate change skeptics, failing to conduct research, appear to act as advocates of an assumption inconsistent with direct measurements and basic principles of climate science.

Given only minor oscillations in solar radiation and cosmic ray activity from the last quarter of the 20th century, the climate change denial syndrome fails to demonstrate a natural cause for global warming, the highest since the Emian (124,000 years-ago), at CO2 and temperature rise rates one to two orders of magnitude faster than the last glacial termination and currently tracking toward conditions analogous to the mid-Pliocene (~3 million years-ago).

It would prove a huge relief, to say the least, had the specter of dangerous climate impasse been shown to be false or, at least, a purely natural process to which civilization needs to mitigate and adapt. Thus Hamilton (2008) states: “The truth is that if any of the skeptics - especially those who do have some claim to expertise in the area - were to undertake a study that cast genuine doubt on the global warming hypothesis and it could pass the tests of professional scrutiny, it would cause a sensation. If it were confirmed, we could all utter an enormous sigh of relief and shower those responsible with prizes and accolades.” Unfortunately this is not the case.

If and when climate change denialists are prepared to visit parts of the Earth severely affected by global warming, and read the voluminous peer reviewed literature in science journals, perhaps they will realize the gravity of the consequences of their misreading of climate science, before it is too late.

Figure 5. Abrupt climate change events during 14,740 – 11.660 years-ago recorded in Greenland ice core (Steffensen et al., 2008). Age determinations are based on ice varve counting and paleo-temperatures on δD (deuterium) analysis. Low temperatures between ~12,900 and ~11,700 years ago correspond to the Youngest dryas period when large scale melting of Laurentian and Fennoscandian ice sheets resulted in abrupt cooling of the North Atlantic region, demonstrating sharp tipping points and an extreme vulnerability of the atmosphere, ocean and cryosphere to warming and cooling feedback processes.


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