Page added on August 2, 2017
The transition that generated the Anthropocene is related to a discontinuity in the energy dissipation rate of the ecosystem. This discontinuity appeared when the ecosystem (more exactly, the “homo sapiens” species) learned how to dissipate the energy potential of the carbon compounds stored in the earth’s crust, mainly in the form of crude oil, natural gas, and coal). These compounds had slowly accumulated as the result of the sedimentation of organic matter mainly over the Phanerozoic era, that is over a timescale of the order of hundreds of millions of years (Raupach and Canadell 2010). The rate of energy dissipation of this fossil potential, at present, can be estimated in terms of the “primary energy” use per unit time at the input of the human economic system. In 2013, this amount corresponded to ca. 18 TW (IEA 2015). Of this power, about 86 % (or ca. 15 TW) were produced by the combustion of fossil carbon compounds.
The thermal energy directly produced by combustion is just a trigger for other, more important effects that have created the Anthropocene. Among these, we may list as the dispersion of large amounts of heavy metals and radioactive isotopes in the ecosphere, the extended paving of large surface areas by inorganic compounds (Schneider et al. 2009), the destruction of a large fraction of the continental shelf surface by the practice known as “bottom trawling” (Zalasiewicz et al. 2011), and more. The most important indirect effect on the ecosystem of the combustion of fossil carbon is the emission of greenhouse gases as combustion products, mainly carbon dioxide, CO2, (Stocker et al. 2013). The thermal forcing generated by CO2 alone can be calculated as approximately 900 TW, or about 1 % of the solar radiative effect (Zhang and Caldeira 2015), hence a nonnegligible effect that generates an already detectable greenhouse warming of the atmosphere. This warming, together with other effects such as oceanic acidification, has the potential of deeply changing the ecosystem in the same way as, in ancient times, LIPs have generated mass extinctions (Wignall 2005; Bond and Wignall 2014).
Burning fossil fuels generate the exergy needed to create industrial structures which, in turn, are used to extract more fossil fuels and burn them. In this sense, the human industrial system can be seen as a metabolic system, akin to biological ones (Malhi 2014). The structures of this nonbiological metabolic system can be examined in light of concepts such as “net energy” (Odum 1973) defined as the exergy generated by the transduction of an energy stock into another form of energy stock. A similar concept is the “energy return for energy invested” (EROI or EROEI), first defined in 1986 (Hall et al. 1986) [see also (Hall et al. 2014)]. EROEI is defined as the ratio of the exergy obtained by means of a certain dissipation structure to the amount of exergy necessary to create and maintain the structure. If the EROEI associated with a dissipation process is larger than one, the excess can be used to replicate the process in new structures. On a large scale, this process can create the complex system that we call the “industrial society.” The growth of the human civilization as we know it today, and the whole Anthropocene, can be seen as the effect of the relatively large EROEI, of the order of 20–30 and perhaps more, associated with the combustion of fossil carbon compounds (Lambert et al. 2014).
However, we should also take into account that fossil carbon is not the only energy potential available to the human industrial system. Fissile nuclei (such as uranium and thorium) can also generate potentials that can be dissipated. However, this potential is limited in extent and cannot be reformed by Earth-based processes. Barring radical new developments, depletion of mineral uranium and thorium is expected to prevent this process from playing an important role in the future (Zittel et al. 2013). Nuclear fusion of light nuclei may also be considered but, so far, there is no evidence that the potential associated with the fusion of deuterium nuclei can generate an EROEI sufficient to maintain an industrial civilization, or even to maintain itself. Other potentials exist at the earth’s surface in the form of geothermal energy (Davies and Davies 2010) and tidal energy (Munk and Wunsch 1998); both are, however, limited in extent and unlikely to be able to provide the same flow of exergy generated today by fossil carbon compounds.
There remains the possibility of processing the flow of solar energy at the earth surface that, as mentioned earlier on, is large [89,000 TW (Tsao et al. 2006) or 87,000 TW (Szargut 2003)]. Note also that the atmospheric circulation generated by the sun’s irradiation produces some 1000 TW of kinetic energy (Tsao et al. 2006). These flows are orders of magnitude larger than the flow of primary energy associated with the Anthropocene (ca. 17 TW). Of course, as discussed earlier on, the capability of a transduction system to create complex structures depends on the EROEI of the process. This EROEI is difficult to evaluate with certainty, because of the continuous evolution of the technologies. We can say that all the recent studies on photovoltaic systems report EROEIs larger than one for the production of electric power by means of photovoltaic devices (Rydh and Sandén 2005; Richards and Watt 2007; Weißbach et al. 2013; Bekkelund 2013; Carbajales-Dale et al. 2015; Bhandari et al. 2015) even though some studies report smaller values than the average reported ones (Prieto and Hall 2011). In most cases, the EROEI of PV systems seems to be smaller than that of fossil burning systems, but, in some cases, it is reported to be larger (Raugei et al. 2012), with even larger values being reported for CSP (Montgomery 2009; Chu 2011). Overall, values of the EROEI of the order of 5–10 for direct transduction of solar energy can be considered as reasonable estimates (Green and Emery 2010). Even larger values of the EROEI are reported for wind energy plants (Kubiszewski et al. 2010). These values may increase as the result of technological developments, but also decline facing the progressive occupation of the best sites for the plants and to the increasing energy costs related to the depletion of the minerals needed to build the plants.
The current photovoltaic technology may use, but do not necessarily need, rare elements that could face near-term exhaustion problems (García-Olivares et al. 2012). Photovoltaic cells are manufactured using mainly silicon and aluminum, both common elements in the earth’s crust. So there do not appear to exist fundamental barriers to “close the cycle” and to use the exergy generated by human-made solar-powered devices (in particular PV systems) to recycle the systems for a very long time.
Various estimates exist on the ultimate limits of energy generation from photovoltaic systems. The “technical potential” in terms of solar energy production in the USA alone is estimated as more than 150 TW (Lopez et al. 2012). According to the data reported in (Liu et al. 2009), about 1/5 of the area of the Sahara desert (2 million square km) could generate around 50 TW at an overall PV panel area conversion efficiency of 10 %. Summing up similar fractions of the areas of major deserts, PV plants (or CSP ones) could generate around 500–1000 TW, possibly more than that, without significantly impacting on agricultural land. The contribution of wind energy has been estimated to be no more than 1 TW (de Castro et al. 2011) in some assumptions that have been criticized in (Garcia-Olivares 2016) Other calculations indicate that wind could generate as much as about 80 TW, (Jacobson and Archer 2012), or somewhat smaller values (Miller et al. 2011). Overall, these values are much larger than those associated with the combustion of fossil fuels, with the added advantage that renewables such as PV and wind produce higher quality energy in the form of electric power.
From these data, we can conclude that the transduction of the solar energy flow by means of inorganic devices could represent a future new metabolic “revolution” of the kind described by (Szathmáry and Smith 1995). (Lenton and Watson 2011) that could bootstrap the ecosphere to a new and higher level of transduction. It is too early to say if such a transition is possible, but, if it were to take place at its maximum potential, its effects could lead to transformations larger than those associated with the Anthropocene as it is currently understood. These effects are hard to predict at present, but they may involve changes in the planetary albedo, in the weather patterns, and in the general management of the land surface. Overall, the effect might be considered as a new geological transition.
As these effects would be mainly associated with solid-state devices (PV cells), perhaps we need a different term than “Anthropocene” to describe this new phase of the earth’s history. The term “Stereocene” (the age of solid-state devices) could be suitable to describe a new stage of the earth system in which humans could have access to truly gigantic amounts of useful energy, without necessarily perturbing the ecosystem in the highly destructive ways that have been the consequence of the use of fossil fuels during the past few centuries.
9 Comments on "What Future for the Anthropocene?"
Plantagenet on Wed, 2nd Aug 2017 11:48 am
The anthropocene is about to end with a mass extinction event.
Cheers!
Apneaman on Wed, 2nd Aug 2017 1:10 pm
The Earth’s Battery Is Running Low
We’ve drained our planet’s stored energy, scientists say, with no rechargeable plug in sight.
https://thetyee.ca/Opinion/2015/08/10/Earth-Battery-Running-Low/
Apneaman on Wed, 2nd Aug 2017 1:45 pm
Miami Is Totally Underwater Right Now Thanks to Tropical Storm Emily
http://www.miaminewtimes.com/news/miami-beach-flooding-due-to-tropical-storm-emily-9542759
Miami just had its hottest month on record
Miami’s scorching summer is only the beginning
http://www.salon.com/2017/08/01/miami-just-had-its-hottest-month-on-record_partner/
Why Did Miami Beach’s Multimillion-Dollar Anti-Flood Pumps Fail?
http://www.miaminewtimes.com/news/miami-beach-floods-from-tropical-storm-emily-overwhelm-sea-level-rise-pumps-9543575
jawagord on Wed, 2nd Aug 2017 4:04 pm
Or maybe swamp land should be left swamp land? Nature trying to reclaim its own should not be a surprise.
“Miami Beach…in 1915…Much of the interior land mass at that time was a tangled jungle of mangroves. Clearing it, deepening the channels and water bodies, and eliminating native growth almost everywhere in favor of landfill for development, was expensive….Collins had begun work on a 2½-mile-long wooden bridge, the world’s longest wooden bridge at the time, to connect the island to the mainland. When funds ran dry and construction work stalled, Indianapolis millionaire and recent Miami transplant Fisher intervened, providing the financing needed to complete the bridge the following year in return for a land swap deal…..and others created much of Miami Beach as landfill by dredging Biscayne Bay; this man-made territory includes Star, Palm, and Hibiscus Islands, the Sunset Islands, much of Normandy Isle, and all of the Venetian Islands except Belle Isle. The Miami Beach peninsula became an island in April 1925 when Haulover Cut was opened, connecting the ocean to the bay, north of present-day Bal Harbour. The great 1926 Miami hurricane put an end to this prosperous era of the Florida Boom…”
https://en.wikipedia.org/wiki/Miami_Beach,_Florida
boat on Wed, 2nd Aug 2017 4:41 pm
ape,
Water around Miami is expected to rise 7 inches in 10 years, 16 inches in 20 years. Is that report correct.
MASTERMIND on Wed, 2nd Aug 2017 7:07 pm
Saudi Aramco CEO believes oil shortage coming despite U.S. shale boom
http://www.foxbusiness.com/markets/2017/07/10/saudi-aramco-ceo-believes-oil-shortage-coming-despite-u-s-shale-boom.html
http://imgur.com/a/EwG3T
http://imgur.com/a/edw7Q
bobinget on Wed, 2nd Aug 2017 8:33 pm
WASHINGTON — President Trump, searching for a reason to keep the United States in Afghanistan after 16 years of war, has latched on to a prospect that tantalized previous administrations: Afghanistan’s vast mineral wealth, which his advisers and Afghan officials have told him could be profitably extracted by Western companies.
Mr. Trump has discussed the country’s mineral deposits with President Ashraf Ghani, who promoted mining as an economic opportunity in one of their first conversations. Mr. Trump, who is deeply skeptical about sending more American troops to Afghanistan, has suggested that this could be one justification for the United States to stay engaged in the country.
To explore the possibilities, the White House is considering sending an envoy to Afghanistan to meet with mining officials. Last week, as the White House fell into an increasingly fractious debate over Afghanistan policy, three of Mr. Trump’s senior aides met with a chemical executive, Michael N. Silver, to discuss the potential for extracting rare-earth minerals. Mr. Silver’s firm, American Elements, specializes in these minerals, which are used in a range of high-tech products.
Stephen A. Feinberg, a billionaire financier who is informally advising Mr. Trump on Afghanistan, is also looking into ways to exploit the country’s minerals, according to a person who has briefed him. Mr. Feinberg owns a large military contracting firm, DynCorp International, which could play a role in guarding mines — a major concern, given that some of Afghanistan’s richest deposits are in areas controlled by the Taliban.
In 2010, American officials estimated that Afghanistan had untapped mineral deposits worth nearly $1 trillion, an estimate that was widely disputed at the time and has certainly fallen since, given the eroding price of commodities. But the $1 trillion figure is circulating again inside the White House, according to officials, who said it had caught the attention of Mr. Trump.
DerHundistlos on Thu, 3rd Aug 2017 4:56 am
bobinget-
We were fed the exact same irrational justification with Iraq. The Bush administration originally projected the invasion would generate a surplus due to Iraqi oil. Instead, the current estimate of the total cost of the intervention is in the $3 trillion range.
Perhaps it’s too much of an intelectual stretch for Trump to make the connection.
Sissyfuss on Thu, 3rd Aug 2017 7:35 am
Derhund, a womans self respect is too much of an intellectual stretch for President Bullsh!t.