The Anthropocene is Not Formally a Geological Epoch  ̶  So, What is It?

David P. Turner / April 3, 2024

A surprising outcome emerged from the March meeting of the Subcommission on Quaternary Stratigraphy (within the International Union of Geological Sciences).  The surprise came in the form of a vote regarding the official status of the Anthropocene concept, with a majority of the subcommission members voting against a proposal to identify the Anthropocene as a new geological epoch.

The term Anthropocene was originally inspired by the observation that the impacts of the human enterprise on Earth’s environment  ̶  notably a rise in the atmospheric CO2 concentration  ̶  have begun to rival those of the background geologic forces.  Since divisions of the geologic time scale are generally associated with major changes in the global environment, naming a new epoch was a reasonable suggestion.

The formal proposal to do so came from the multidisciplinary Anthropocene Working Group (AWG), which has deliberated on the issue for the last 14 years.  The AWG proposal specified that the Anthropocene be named a new epoch, with a beginning point in the early 1950s.  Its stratigraphic marker was to be a layer of chemical residues from post-World War II nuclear weapons testing. 

The Vote

The vote against designating the Anthropocene as a new Epoch was a surprise because the proposal had been made with a strong scientific foundation and had a lot of support.  The decision against the proposal was not because the Anthropocene is geologically insignificant, but rather because the Anthropocene concept is highly significant to many disciplines besides geology.  In the last 20 years, the concept has received widespread attention in both academia and popular media.  Indeed, the term has taken on a life of its own, a life outside the staid world of Quaternary Stratigraphy.

The term Anthropocene has come to signify a rupture in human history  ̶  the end of a time when the biophysical environment was mostly a background to the march of human progress.  The rupture is evident from a suite of global indicators, ranging from oil consumption to the rate of deforestation, that all began rising dramatically in the last 100 years.  The word Anthropocene now has broad cultural significance; it implies that humanity has acquired a new responsibility to self-regulate, or face its own demise from a self-induced inhospitable environment. 

The negative vote within the subcommission was also based on a more technical issue about whether, considering that humans have been altering the environment at many scales for many thousands of years, the beginning of the Anthropocene Epoch could be narrowed down to the early 1950s.

An alternative proposal, with considerable cross-disciplinary support, is to designate the Anthropocene a geologic “event”.  This term is used in the geosciences to reference a wide variety of Earth system changes or transformations.  Designating something as an event does not require the kind of formal approval process associated with designating an epoch.

The Scope of the Anthropocene Event

Despite this quasi-downgrade to Event status, the Anthropocene has really just begun and will ultimately have a massive impact on the Earth system.  The Anthropocene Event, as we will call it here, will eventually push the global mean temperature up 2-3 oC or more, a range associated with the early Pliocene Epoch 3-5 million years ago (Figure 1).  Because of human influences on the atmosphere, Earth may well miss its next scheduled glacial period (as prescribed by the Milankovitch solar forcings).  

The graphic is a time series plot going back 5 million years ago showing the trend in global mean temperature.

Figure 1.  The geologic record of global mean temperature, with projections to 2100.  The x-axis units differ by panel.  The graphic is adapted from work by Glen Fergus.

What is also quite extraordinary is that the Anthropocene Event is concurrent with the origin of a whole new Earth system sphere – the technosphere.  This term refers to the accumulation of human artifacts  ̶  including buildings, transportation networks, and communication infrastructure  ̶  that now cloaks the surface of the Earth.

From an Earth system science perspective, the parts of the Earth system are its spheres, i.e. the lithosphere, atmosphere, hydrosphere, cryosphere and biosphere interact with each other over geological time to determine the state and dynamics of the Earth system.

The biosphere (defined by geochemists as the sum of all life on Earth) is of particular interest here.  The biosphere did not exist early in Earth’s history, but after the origin of life and its proliferation around the planet, the impacts of the biosphere on Earth’s energy flow and chemical cycling became profound (e.g. the oxygenation of the atmosphere).

Now the technosphere, a product of human history, has joined the biosphere as an active force on the surface of the planet.  Like the biosphere, it has mass and uses energy to maintain itself and grow.  It has become a significant factor in the global biogeochemical cycles.  Unlike the biosphere, the technosphere has not been around long enough to become well integrated with the rest of the Earth system, e.g. it largely does not recycle its own waste

During the Anthropocene Event, the technosphere could be destroyed or self-destruct by various mechanisms, or could come into a stable state of sorts with the rest of the Earth system, in which case it might last quite a long while. 

The Role of the Anthropocene Event in Cultural Evolution

Transition to global sustainability will require the emergence and evolution of a global culture, i.e. a globally shared set of beliefs and practices.  The Anthropocene Event is a concept that can help anchor a robust integration of human history and Earth history.

Transdisciplinary investigations covering a wide range of issues associated with managing the human enterprise on Earth  ̶  including  aspects of the social sciences, humanities, and biophysical sciences  ̶  may hinge on having this shared reference point. 

The Right Call

In light of the need for broadly unifying concepts related to global environmental change, I think the geologists made the right call.  The Anthropocene has become a politically potent idea and deserves the widest possible attention in the domains of scholarship, education, entertainment, and advocacy.

This post was featured on the Millennium Alliance for Humanity and the Biosphere (MAHB) web site.

Extreme Weather Events, Social Tipping Points, and a Step-Change in Climate Change Mitigation

David P. Turner / August 12, 2023

Figure 1.  Annual additions of coal-fired electricity generation in recent years. Image Credit.

The rash of extreme weather events and associated impacts on humans around the world in recent years (especially 2023) is setting the stage for radical societal changes at the local and global scale with respect to climate change mitigation efforts.  One recognizable step-change in that direction would be a planet-wide cessation in the issuing of permits to build new coal-fired power plants.

Extreme weather events (droughts, heat waves, fires, and floods) are very much in the news recently everywhere on the planet.  Within the scientific community, these events are understood as part of normal weather variability, but also as attributable in part to on-going anthropogenic climate warming.  This year (2023) is proving to be especially prone to extreme weather events because of an extra boost of warming associated with an El Nino event

Globally, climate scientists suggest that 85% of people have suffered from extreme weather events that are partially attributed to climate change.

Social science research has shown that people respond markedly to their personal experience with weather events.  In the U.S., polls (2022) find that 71% of Americans say their community has experienced an extreme weather event in the last 12 months and 80% of those respondents believe climate change contributed at least in some measure to the cause.  In China and India, recent polls suggest strong awareness about the climate change issue and support for governmental mitigation policies. 

Admittedly, awareness of the issue is much lower elsewhere.  Some countries in Sub-Saharan Africa have relatively high proportions of inhabitants that have “never heard of” climate change. 

Nevertheless, billions of people around the world are making the connection between their personal experience of an extreme weather event and climate change.  Perhaps a new level of political support for mitigation efforts will emerge?

The concept of tipping points is common in the climate change literature, i.e. that distinct large-scale processes such as the melting of the Greenland ice sheet eventually reach a point where strong positive (amplifying) feedbacks are engaged and the process becomes irreversible (on a human timescale).  The concept has also begun to be applied to changes in social systems.  Given widespread changes in personal views about climate change, and perhaps appropriate societal interventions, particular societies and ultimately the global society may tip into a strong climate change mitigation stance.

A clear step-change in the global climate change mitigation effort would be a planet-wide cessation of permits for building new coal-fired electricity generating plants.  Coal emissions contribute about 40% to global fossil fuel emissions.

Tremendous momentum has already built up in that direction based on anti-coal environmentalism and the improving cost differential between coal power and other energy sources (primarily natural gas and renewables).  The U.S. and E.U. do not formally prohibit new coal plants but few have been built in recent years.

The World Bank, the International Monetary Fund, and China’s Belt and Road Initiative are no longer supporting construction of new coal-burning facilities and many countries have made commitments in their Nationally Determined Contribution statements that will require reduction in the burning of coal.

Remarkably, India has recently announced consideration of a policy to prohibit planning of new coal-fired plants for at least the next 5 years.

China is still permitting and building about 2 coal-fired power plants per week.  It is no doubt a big ask for China to adopt a no-new-coal-plants policy.  However, the country is suffering significantly from extreme weather events, from the negative effects of air pollution from coal combustion, and from the interaction of the those two factors.  And China leads the world in production of renewable energy. 

The autocratic style government in China is not conducive to bottom-up social tipping dynamics, but how the Zero-Covid policy was dropped is an interesting case study in social change.  Rumblings within the bureaucracy and multi-city protests appear to have influenced Xi Jinping to make the radical policy shift.  Given its massive contribution to the global total of new coal plants coming on line (Figure 1), if China stopped issuing building permits, the battle would be nearly won.

Two caveats to ending coal-fired power plant construction should be considered.  First is that the global demand for electricity will likely increase in the future because of 1) growth in the global population and increased per capita energy use in the developing world, 2) increasing demand from the conversion to electricity powered vehicles, and 3) wide application of AI technology.  To generate that energy from non-coal sources will be challenging but feasible.  The second consideration is the possibility of Carbon Capture and Storage, i.e. continuing to burn coal but capturing the associated CO2 emissions and sequestering them belowground.  This technological fix sounds good in theory but thus far decades of research and pilot studies do not support that it can be economically implemented at scale.

Across all of humanity, cultural differences tend to build silos around each society – especially differences in language, religion, and degree of technological development.  That isolation has diminished over the course of human development to this point, and with the advent of the Anthropocene we can begin to see humanity as a unified whole and as capable of working collaboratively  on global environmental change issues.

When the world does achieve consensus on ending the construction of new coal power plants, it will be a step-change in the global climate change mitigation effort.  It will also signal a step towards the emergence of a collective humanity, an indication that “we” can agree on, and implement, a path to a sustainable future on Earth.

Commentary on “The Letter: Laudato Si Film”, and “Laudato Si” (the encyclical)

David P. Turner / January 23, 2023

Pope Francis issued an encyclical (Laudato Si) in 2015 about “care for our common home”.  The document discussed a wide range of global environmental change topics, notably climate change and loss of biodiversity.  It aimed to provide a moral rationale for simultaneously addressing the issues of global environmental change and human inequity.  The encyclical runs to nearly 200 pages and is not a light read.  Perhaps to make its message more accessible, the Vatican recently produced and released (October 12, 2022) a related video (The Letter: Laudato Si Film), clocking in at 81 minutes.

The encyclical was released just prior to the United Nations Framework Convention on Climate Change COP21 meeting that was held in Paris.  The product of that meeting was The Paris Agreement, which is widely perceived as a significant step towards mitigating global climate change.  Considering that there are 1.3 billion Catholics who ostensibly consider the pope infallible, the encyclical may well have strengthened global political will to seriously address the climate change issue.

The film is a very different vehicle from the encyclical, leaving behind the encyclical’s more controversial aspects (discussed below) and presenting an engaging narrative about global change with good visuals and music.  The premise of the film is that the Pope invites a set of 5 people from widely different backgrounds to Rome for a “dialogue” about the encyclical.

The five participants included the following.

1.  A poor black man from Senegal who is considering an attempt to migrate to the EU because of the deteriorating environment in his home country.  He represents the billion or so people expected to be displaced by climate change this century.

2.  An indigenous man from Brazil whose forest homeland in the Amazon Basin is under siege.  He represents forest dwellers throughout the tropical zone who are losing their homes to rampant deforestation.

3.  A young woman from India.  She represents the voice of a younger generation who will be forced to deal with the massive environmental change problems caused by their elders (intergenerational inequity).

4.  A man and a woman from the U.S. who are scientists working on monitoring and understanding coral reef decline.  They represent the community of research scientists trying to understand climate change impacts and what to do about them.

Each participant is shown in their home environment receiving a letter of invitation from the Pope.  The film then documents their experiences in Rome, including discussions amongst themselves and with the pope.

The film was engaging and had a positive message about the need for solidarity across all humanity in the face of threats from climate change and loss of biodiversity.

However, I did have some concerns.

First was that the film seemed to be more about the victims of global environmental change (both human and nonhuman) than about the solutions.  The participants were certainly sincere, and helped put a human face on the challenges ahead; but little was said about the personal changes and the political realities involved in transitioning to global sustainability.

Second was the emphasis on climate change as the sole driving force in the current surge of migration.  Climate change is indeed driving international migration but a host of other factors are of equal or greater importance, including civil war, overuse of local natural resources, and gross defects in local governance.  If indeed a billion people will potentially be displaced by climate change in this century, they can’t all migrate.  Alternatives to migration include foreign aid for adaptation, and aid to improve local educational opportunities that would help train citizens for local economic activity and help limit population growth (the fertility rate in Senegal is 4.3 births per woman).

Third was that the film may point viewers towards reading the actual encyclical, which has inspired much more commentary  ̶  both positive and negative  ̶  than the film.

The proclamations of the pope usually do not draw much attention from the scientific community, but in the case of the Laudato Si encyclical, the science of global environmental change is front and center.

As I started reading the encyclical, I was surprised because the tone sounded as if it were written by an environmental science policy analyst rather than a religious leader (apparently there was a ghost writer).  The scientific causes of climate change and biodiversity loss were reasonably explained, and it was refreshing to see the “dominion” over the Earth given to humanity by God presented more in terms of responsibility to conserve environmental quality than as a license to exploit limitless natural resources.  The intrinsic value of all species, independent of their utility to humans, was recognized.  When the text veered into explaining the Christian belief system (e.g. the Holy Trinity), it lost cogency from an Earth system science perspective.

The encyclical was well received by scientific authorities in some cases, perhaps because the Pope broadened the usual rationales for caring about climate change and biodiversity loss to include the moral dimension.  Wealth-based inequity (relatively wealthy people have caused most of the greenhouse gas emissions but it is relatively poor people who will suffer the greatest impacts) and intergenerational inequity (recent generations have caused most of the greenhouse gas emissions but future generations will suffer the greatest impacts of climate change) are  clearly moral issues.

Critiques of the encyclical have referred to its limited regard for the full suite of dimensions (technical, political, and economic) needed to address global environmental change.  The encyclical comes across as hostile to the “technocratic paradigm”, suggesting some technofixes will induce more problems than they solve.  There is much emphasis on reducing excess consumption.  Realistically though, there must be a revolutionary change in technology towards renewable energy and complete product recycling.  Likewise, beyond calling for a stronger climate change treaty (as the Pope did), we must have stronger institutions of global environmental governance, and new economic policies that prioritize sustainability.

The section of the encyclical about population control was especially provocative.  The pope took issue with calls for limiting population growth for the sake of the environment, a position  consistent with formal Catholic doctrine against contraception.  This view rings false, however, because of the contradiction between saying that Earth’s natural resources are limited (as stated several times in the encyclical) and that all humans deserve a decent quality of life (which inevitably consumes natural resources), while at the same time maintaining that high rates of population growth in developing countries are not an issue.  In contrast, the recent World Scientists’ Warning of a Climate Emergency 2022  called for “stabilizing and gradually reducing the human population by providing education and rights for girls and women”.  Ehrlich and Harte also point out that unchecked population pressure on food supply and natural resources pushes development into ever more vulnerable ecosystems, and fosters ever more inegalitarian forms of government.

Pope Francis deserves credit for bringing attention to the moral questions raised by anthropogenically-driven global environmental change.  Our contemporary materialistic and instrumental value system has proven to be unsustainable and should indeed be influenced by values based on respect for the natural environment, as well as values derived from human solidarity.  The Laudato Si encyclical and film (along with associated praise and critique) are contributing in a positive way to the ongoing process of cultural evolution, which has now begun to operate at the global scale.

More Blows to Humanity’s Self-image

heliocentric universe
Cellarius’s chart (1661) illustrating a heliocentric model of the universe, as proposed by Nicolaus Copernicus.  Image Credit.

David P. Turner / October 2, 2022

Copernicus, Darwin, and Freud are credited with delivering major blows to humanity’s self-image. They didn’t do it on their own of course, but their ideas were notably illuminating.  Here, I revisit their insights and discuss two additional blows of that type rendered in more recent years.  Awareness of the human limitations implied by these blows may help save us from our present environmental predicament.

Copernicus (1473 -1543) established that – contrary to Church dogma – Earth rotated on its axis and revolved around the sun.  Humans could no longer maintain that we are living at the center of the universe.  The scientific discipline of astronomy has gone on to reveal how remarkably tiny this planet really is in the context of an immense universe.  Knowing that we live on a small planet points to biophysical limits on our current demands for natural resources.

Darwin (1809 – 1882) elucidated the theory of biological evolution, and the corresponding fact that Homo sapiens originated the same way every other animal species on this planet did through natural processes.  We were no longer a special creation of an omnipotent, benevolent god who dictates our aspirations and values.  Ironically, though, humanity is coming to have a kind of dominion over the Earth even without the hand of god.

Freud (1856 – 1939) suggested that unconscious processes within our brains have a substantial influence on our thoughts and emotions.  He turned out to be wrong in many respects, but his primary insight had merit.  We are not even in full control of our own minds.  Contemporary cognitive science aims to understand (1) the function (adaptive significance) of specific mental processes, (2) the representations and algorithms by which those processes are implemented, and (3) the underlying neurobiological mechanisms.  Insights along those lines may help modify our destructive impulses.

The two recent blows to our self-image come from a biologist and an atmospheric chemist.

In the 1970s, Harvard professor E.O. Wilson (1929 – 2021) fostered the development of the new discipline of sociobiology – the study of animal social behavior.  He applied its concepts to Homo sapiens, as well as to ants (his favorite object of study).  What he asserted (albeit in the face of raging controversy) is that humans have significant genetic influences on our thinking and behavior.  Our capacity for altruism (self-sacrifice) and jealousy are notable example of traits which evolution has likely shaped.  As with the first three blows, this realization forces us to question our spontaneous motivations and actions (e.g. our acquisitiveness).

The fifth blow is truly aimed at the whole of humanity.  Around 2000, atmospheric chemist Paul Crutzen (1933 – 2021) helped consolidate a wide array of observations by Earth System Scientists concerning the baleful influences of humanity on the biosphere and the global environment.  He suggested that we have entered a new geologic epoch – the Anthropocene. 

In the scientific Anthropocene narrative, humanity has become the equivalent of a geologic force; we are now capable of significantly altering the global biogeochemical cycles.  This shocking realization and consequent shift in worldview have been characterized as the “second Copernican revolution”.

Unfortunately, we are altering the global environment in a way that may ultimately be self-destructive (e.g. by inducing rapid global climate change).  Our self-image must therefore include the conclusion that we are an existential threat to ourselves.

Recognition of the Anthropocene epoch places a new responsibility on each of us as individuals, and a new responsibility on our species as a whole, to begin managing ourselves – and to some degree begin managing the Earth system in support of global sustainability.

The prescription for better integration of the human enterprise (the technosphere) with the Earth system requires that humanity become aware of itself as a social entity, having agency at the global scale, before it can learn to self-regulate and reintegrate with the Earth system.  Awareness of the five blows covered here introduces an element of humility to this project of understanding ourselves as a planetary phenomenon.

Peak Technosphere Mass and Global Sustainability

David P. Turner / June 21, 2022

The technosphere is a component of the contemporary Earth system.  Like the biosphere  ̶  also an Earth system component  ̶  the technosphere has a mass, requires a steady input of materials, and utilizes a throughput of energy.

Technosphere mass is composed of all human-made objects, including the mass of buildings, transportation networks, and communication infrastructure.  That mass has built up over centuries, and is still accumulating at the rate of 3-5% per year.

The material inputs to the technosphere (besides fossil fuels) include food, water, wood, and minerals.  These inputs are derived from the geosphere, hydrosphere, and biosphere  ̶  often with destructive consequences.  Upward trends in consumption of these inputs are associated with an upward trend in global Gross Domestic Product of about 3% per year.

The energy that drives technosphere metabolism comes mostly from fossil fuels (80%).  Global fossil fuel consumption was increasing at a rate of about 5% per year (2009 2019) until the recent dip associated with the Covid-19 pandemic.

The growing impact of the technosphere on the Earth system has been widely documented by the scientific community (IPCC, IPBES) and scenarios for a sustainable high technology global civilization require that technosphere mass, inputs, and use of fossil fuels peak as soon as possible.  If the peaks are left to occur spontaneously, the outcome may well be a collapse of civilization driven by the stress of global environmental change, rather than a soft landing at a state of global sustainability.

Peak Technosphere Mass

Earth system scientists have estimated both current technosphere mass (in use) and the current biosphere mass (i.e. including all microbes and multicellular organisms).  Coincidentally, those numbers are of approximately the same magnitude (about 1018 g).  However, technosphere mass is increasing substantially each year, while the multi-century trend in biosphere mass and diversity is towards a diminished and depauperate state.  The technosphere is essentially now growing at the expense of the biosphere

There are a few cases at the national scale where peak technosphere mass has been reached, albeit not specifically by design.  In Japan, the number of automobiles is close to its peak and the length of pipelines and high-speed rail are not increasing.  Ninety-two percent of the population is urban.  Total energy use is declining.  These trends can be traced to a high level of development and a declining population. 

A low birth rate and a low level of immigration account for the decreasing population.  As a case study, Japan points to the role of population size in stabilization of technosphere mass.  Per capita technosphere mass is relatively high, but is not rising because the country is already highly developed.  Hence, technosphere mass at the national scale has likely peaked.  By 2050, population is projected to decline about 25% from its peak, which may allow for a decrease in national technosphere mass.

China is an interesting case at the other extreme of technosphere mass dynamics, with vast on-going growth of its technosphere mass.  Despite a low birth rate, China’s population is still growing (slowly).  More importantly, per capita wealth is increasing.  Consequently, the number of people owning modern housing and an automobile is rising rapidly.  The government is also making huge investments in infrastructure – notably in power plants and high-speed rail.

Humans do sometimes place limits on technosphere mass expansion  ̶  as in the urban growth boundaries around cites in the state of Oregon (USA), and in areas of land and ocean that are in a protected status (e.g. wilderness areas in the U.S.).  Idealized prescriptions for future land use include 30 X 30 and 50 X 50.  These values refer to 30 percent of Earth’s surface dedicated to biosphere conservation by 2030, and 50% by 2050.  Seventeen percent of land and ten percent of ocean are in a protected status at present.

These conservation goals are consistent with the strong global trend towards urbanization.  Over half of humanity now lives in an urban setting, a proportion that is projected to rise to 66% by 2050.  The key benefits of urbanization with respect to technosphere mass are that 1) it potentially frees up rural land for inclusion in biosphere protection zones, 2) the per capita technosphere mass of urban dwellers is less than that of equally wealthy rural dwellers (e.g. living in multiple unit buildings as opposed to living in dispersed separate building, and using public transportation rather than everyone owning an automobile), and 3) birth rates decline as people urbanize, which speeds the global demographic transition.

Peak technosphere mass will occur sometime after peak global population.  That assumes global per capita technosphere mass will also peak eventually, which brings up the fraught issue of wealth inequality.  Individual wealth is equivalent in some ways to individual technosphere mass (e.g. owning a yacht vs. owing a row boat).  Given that there are biophysical limits to human demands on the Earth system, the nearly 8 billion people on the planet cannot all live like billionaires.  From a humanist perspective, a wealth distribution that brings standards of living for everyone up to a modest level is desirable.  That worthy principle is the guiding light for significant philanthropic efforts and should figure into policies related to taxation of income and wealth.  Whether to explicitly attempt to reduce the ecological footprint of the wealthy is a related, and highly contested, question.

An estimate of technosphere mass that includes landfills, and other cases of human-made objects not in use, is much larger that the 1018g estimate of technosphere mass in use.  Indeed, geoscientists looking for a depositional signal for the Anthropocene are considering discarded plastic as a marker.  It will take a concerted effort to decrease material flows into landfills before we will see a peak in unused technosphere mass.

Peak Technosphere Input of Material Resources

Humans already appropriate around 25% of terrestrial net primary production, and divert 54% of available fresh water flows.  Mining geosphere minerals for input to the technosphere covers approximately 57,000 km2 globally.

The concept of the Great Acceleration captures the problem of exponentially rising technosphere demands on the Earth system.  It refers to the period since 1950 during which many metrics of human impact on the global environment have risen sharply (Figure 1).  Obviously, those trends cannot continue.  Humanity must bend those usage curves and redesign the technosphere to maintain itself sustainably. 

Figure 1. The Great Acceleration refers to the period after 1950 when impacts of the technosphere on the global environment grew rapidly.  Image Credit: Adapted from Welcome to the Anthropocene.

Some metrics, like wild fish consumption, have already peaked but that is because the resource itself has been degraded.  Future increases in fish consumption will have to come from cultured sources.

Many rivers around the world are already fully utilized (and then some), e.g. the Colorado River Basin in Southwestern United States.  Policies like tearing out lawns in Las Vegas to save water portend the future.

Global wood consumption increases several percent per year and is projected to continue doing so for decades.  Much of current industrial roundwood production is from natural forests, sometimes in association with deforestation.  Forest sector models suggest that high yield plantations in the tropical zone could supply most of the projected global demand for industrial wood, thus reducing pressure on natural forests.

Resource use efficiency can be increased by extending product lifetimes (e.g. automobiles), boosting rates of recycling (e.g. paper), and improvement in design (e.g. more efficient solar panels).  Again, these changes must be made along with the stabilization of population if we are to end continuing growth of technosphere demand for natural resources.

Peak Technosphere Consumption of Fossil Fuels

An abrupt decline in carbon emissions from fossil fuel combustion in 2020 was induced by the COVID-19 pandemic, hinting at the possibility that 2019 was inadvertently the year of peak fossil fuel emissions

In 2021, fossil fuel emissions roared back to about the level of 2019.  Emissions in 2022 will likely be impacted significantly by the war in Ukraine, possibly reducing global emissions since moves to avoid purchasing Russian gas, oil, and coal are driving up prices for fossil fuels.  Certainly, there is increased political support in the EU and elsewhere for rapid transition from fossil fuels to renewable energy sources.  Technological constraints will slow the pace of that conversion, and emissions will continue to increase in many countries outside the EU (especially China and India).  Thus, the actual peak year for global fossil fuel emissions is uncertain.

The faster that fossil fuel-based energy is replaced by renewable energy sources, the better chance of avoiding a climate change catastrophe.  Multiple policy rationales, beside reducing carbon dioxide emissions, support the goal of a global renewable energy revolution.

Note that total energy consumption need not decline within the context of global sustainability if the energy sources are renewable.  Projected peak global energy use – with accounting for increasing efficiency, population growth, and the curing cases of energy poverty – is on the order of current global energy use.

Conclusion

The sprawling mass of the technosphere, its demands on natural resources, and its flood of chemicals and solid waste into the global environment, have begun to diminish the biosphere and threaten human welfare on a massive scale.  Humanity must begin to work as a collective to redesign technosphere metabolism such that it conforms to the biophysical limits of the Earth system.

Planetary Citizenship

David P. Turner / March 7, 2021

The developmental task of building a personal identity is becoming ever more complicated.  While some aspects of identity come with birth, others are adopted over the course of maturation.  Increasingly, each person has multiple identities that are managed in a complex psychological juggling act.

Citizenship − generally defined in terms of loyalty to the society within a specified area − is a key component of personal identity.  National citizenship most readily comes to mind, but the term is also used at other levels of organization.  Members of a tribe, residents concerned about watershed protection, and neighbors attending to local quality of life all qualify as citizens.

The concept of citizenship at the planetary scale is rather new, in part because our global governance infrastructure (environmental, geopolitical, and economic) is rudimentary.  However, if there is to be a purposeful (teleological) attempt to mitigate and adapt to global environmental change, we residents of Earth must become planetary citizens.

The impetus to identify as a planetary citizen typically comes from growing awareness of planetary scale environmental threats to human welfare.  The result is a commitment to rein in the human enterprise (the technosphere) and work towards global sustainability

Earth system scientists generally reject the Gaian notion that the planet is in some way self-regulating or purposeful.  But if humanity indeed manages to join together and intentionally reverse the trend of rising greenhouse gas concentrations and mass extinction, the Earth system as a whole (Gaia 2.0) would in a sense gain purpose.

Embrace of planetary citizenship is a pushback against unbridled individualism.  In the widely held neoliberal belief system, individuals are viewed most fundamentally as autonomous consumers who live in a biophysical environment that is a limitless source of materials and energy as well as a limitless sink for wastes.  In fact, the human impact on the global environment is a summation of the resource demands from the 7.8 billion people who now inhabit the planet.  The cumulative impact of humanity has clearly begun to induce changes in the Earth system that endanger both developing and developed nations. 

Rights and Responsibilities

Planetary citizens have rights, in principle.  As noted though, the global governance forums for establishing those rights are weak.  In the realm of environmental quality, a planetary citizen certainly should have a right to an unpolluted environment. 

Correspondingly, a planetary citizen’s responsibilities include understanding their own resource use footprint, and endeavoring to control it (e.g., having fewer children).  Understanding the environmental impacts of their society and advocating in support of conservation-oriented governmental policies and actions (e.g., by voting) is also essential.

Because global change is happening so quickly and persistently, a commitment to lifelong learning about local and global environmental change is a foundation of planetary citizenship.

Identifying with any collective evokes a tension between personal autonomy and obligations to the greater good.  Thus, the addition of planetary citizenship to personal identity creates psychological demands.  Mental health requires that those new demands (e.g., pressure for less consumerism and more altruism) be calibrated to individual circumstances and to the state of the world.

Collective Intelligence

Possibilities for the emergence of collective intelligence and agency among planetary citizens at various scales have grown rapidly as the Internet has evolved.  Besides the general sense of a global brain emerging from the mass of online communication, various online groups now specifically address global environmental change issues, e.g. the MIT Center for Collective Intelligence sponsors a crowdsourced web site aimed at finding solutions to climate change.  

Civil society organizations like 350.org, Millennium Alliance for Humanity and the Biosphere, and Wikipedia are testaments to the power of collective intelligence among planetary citizens.  Participation of planetary citizens in self-organized groups of activists creates a sense of agency, which can be hard to find when a person confronts the enormity of global environmental change on their own.  What is glaringly missing is a planetary forum for global environmental governance, something like the proposed World Environment Organization.

Global Citizenship

It is worth making a distinction between planetary citizenship and global citizenship.  Both concepts are relevant to building global sustainability, with planetary citizenship more focused on the biophysical environment and global citizenship more concerned with human relationships. The global perspective is fundamentally political.

Global Citizenship is often discussed in the context of Global Citizenship Education (GCE).  GEC theory commonly calls for “recognizing the interconnectedness of life, respecting cultural diversity and human rights, advocating global social justice, empathizing with suffering people around the world, seeing the world as others see it and feeling a sense of moral responsibility for planet Earth”.

Traditional GCE theory may be oriented around experiential learning by way of immersive experiences in other cultures, often including volunteer work.  However, persistent concerns that the relationship of visitor to host replicates the colonial model of dominance have led to more critically oriented versions of GCE theory.  Here, the emphasis is on examining injustices and power differentials among social groups and evaluating effective means to foster greater equity. 

The thrust of the global citizenship concept tends towards differentiating the parts of humanity and fulfilling the obligation to address injustices of all kinds; the thrust of planetary citizenship is on humanity as a collective entity playing a role in Earth system dynamics.  A comprehensive approach to teaching global citizenship would emphasize both  aspects and even transcend them.

Pedagogy

Since identity as a planetary citizen is a choice, the question of how education can be designed to foster that choice is significant.

The idealized outcome of education for planetary citizenship is a human being who understands the impacts of the technosphere on the Earth system and has a willingness to engage in building global sustainability (Go Greta Thunberg!).  These individuals would share a sense of all humans having a common destiny.

Two disciplines are particularly relevant. 

The field of Big History covers the history of the universe leading to the current Earth system.  It juxtaposes cosmic evolution, biological evolution, and cultural evolution to give perspective on how humanity has become aware of itself and come to endanger itself.  A recently developed free online course in Big History aimed at middle school and high school students nicely introduces the subject.  My own text, The Green Marble, and my blog posts such as A Positive Narrative for the Anthropocene, examine Big History at a level suitable for undergraduate and graduate students.

The field of environmental sociology is likewise important.  It explores interactions of social systems with ecosystems at multiple spatial scales.  The concept of a socioecological system, composed of a specific ecosystem and all the relevant stakeholders, is a core object of study.  Nobel prize winning economist Elinor Ostrom helped elucidate the optimal structural and functional properties of socioecological systems at various scales.

Conclusion

Identifying as a planetary citizen means seeking to understand humanity’s environmental predicament and trying to do something about it.  An important benefit from this commitment is the acquisition of a sense of agency regarding global environmental change.  The aggregate effect of planetary citizenship across multiple levels of organization (individual, civil society, nation, global) will be purposeful change at the planetary scale.

Can Humanity be a “We”?

David P. Turner / February 16, 2020

The peer-reviewed literature and the popular media today abound with concern about human-induced global environmental change.  Articles often argue that global scale problems require global scale solutions: humanity is causing the problem and “we” must rapidly implement solutions.  Environmental psychologists have found that people who sympathize with or identify with a group are energized to support its cause.  Can a majority of human beings identify with humanity in a way that motivates collective change towards global sustainability?      

Let’s consider several key constraining factors and unifying factors relevant to making humanity a “we” with respect to global environmental change.

Constraining Factors

Notable sociopolitical factors that impede global solidarity include the following.

1.  Climate Injustice among Nations 

In the process of their development, the most developed countries burned through a vast amount of fossil fuel and harvested a large proportion of their primary forests, hence causing most of the observed rise in atmospheric CO2 concentration.  But these countries are now asking the developing countries to share equally in the effort to curtail global fossil fuel emissions and deforestation to prevent further climate change.  At the same time, the impacts of climate change will tend to fall most heavily on the developing countries because of their lower capacity for adaptation.  The developing countries are pushing back on the basis of fairness, e.g. the outcome of the Kyoto protocol (albeit now obsolete) was that only the developed countries made commitments to reduce greenhouse gas emissions.

2. Rising Nationalism

Economists generally agree that economic globalization has spurred the global economy and helped lift hundreds of millions of people out of extreme poverty.  However, globalization of the labor market beginning around 1990 has also meant a large transfer of manufacturing from the developed to the developing world – and with it many jobs.

Likewise, immigration is helping millions of people a year find a better life by leaving behind political corruption, resource scarcity, and environmental disasters. 

Unfortunately, one effect of economic globalization and mass immigration has been political backlash within developed countries in the form of populism and nationalism.  Hypersensitivity to loss of national sovereignty is not conducive to international agreements to address global environmental change issues.

3.  Climate Science Skeptics

Although the global scientific community is broadly in consensus about the human causes of climate warming and other global environmental change problems, the rest of the world is more divided.  Most people in the U.S. accept that the global climate is changing, but only about half accept the scientific consensus that climate warming is caused by human actions.  Sources of skepticism about climate science include religious beliefs and vested interests. 

4.  Economic Inequality

Wealth inequality, both within nations and among them, is a pervasive feature of the global economy.  The rich end of the wealth distribution contributes to the vested interests problem as just noted.  At the poor end of the wealth distribution, the hierarchy of needs discourages concern for the environment; solidarity with the fight against climate change is a luxury when you are starving.

These four constraining factors are deeply rooted and are only the head of a list that would also include competition for limited natural resources and geopolitical conflict.  It is daunting to think about overcoming these obstacles to a “we” that includes all of humanity.  There are substantive ongoing research and applied efforts (not documented here) to overcome them, but in a general way let’s consider some equally significant factors that may help foster a global “we”.

Unifying Factors

The following rather disparate set of factors supply some hope for human unification under the banner of environmental concern.

1.  Our Genetic Heritage

Humans are social creatures.  Sociobiologists, such as Harvard Professor E.O. Wilson, have argued that many of our social impulses are genetically based.  We have an instinctual propensity to identify with a particular social group, and to draw a distinction between that group (us) and outsiders (them).  The average ingroup size during the hunter/gatherer phase of human evolution, which largely shaped our social instincts, is believed to have been about 30 people.  Remarkably, the size of the social group that humans identify with has vastly expanded over historical time − from the level of tribe, to the level of village, empire, and the modern nation-state.  Conceivably, that capacity could be extended to the global scale:  we might all eventually consider ourselves citizens of a planetary civilization.

The historical expansion of social group size was driven in part by military considerations  − the need to have a larger army than your neighbor.  Obviously, this rationale breaks down at the global scale, but a distinct possibility for inspiring global solidarity is the looming threat of global environmental change. 

Note that being a citizen of the world does not require rejecting one’s local or national culture.  Multiple sources of identity could include being an autonomous individual, being a member of various ingroups, and being a member of humanity in its entirety.

2.  The Advance of Earth System Science

A conspicuous general trend favorable to achieving a collective sense of responsibility for managing human impacts on the Earth system is growth in our scientific understanding of the Earth system.  From studies of the geologic record, scientists know that Earth’s climate has varied widely, from cool “snowball” Earth phases to relatively warm “hothouse” Earth phases.  Greenhouse gas concentrations have consistently been an important driver of global climate change, which gives scientists confidence that as greenhouse gas concentrations rise, Earth’s climate will warm. 

The scientific community also has expansive monitoring networks that reveal the exponentially rising curves for metrics such as the atmospheric CO2 concentration.  Earth system models that simulate Earth’s future show the dangers of Business-as-Usual scenarios of resource use, as well as the benefits of specific mitigation measures.  At the request of the United Nations, the global scientific community periodically assembles the most recent research about climate change, the prospects for mitigation (i.e. reduction of greenhouse gas concentrations), and the possibilities for adaptation. 

If improved understanding of the human environmental predicament can filter down to the global billions, we might hope for a strengthening support for collective action.

3.  The Evolution of the Technosphere

The technosphere is a new global-scale part of the Earth system.  It joins the pre-existing geosphere, atmosphere, hydrosphere, and biosphere.  However, just as the evolution of the biosphere was a major disturbance to the early Earth system, the evolution of the technosphere is proving to be disruptive to the contemporary Earth system.  

Around 2.3 billion years ago, cyanobacteria evolved that could split water molecules (H2O) in the process of photosynthesis.  The resulting oxygen (O2) began to accumulate in the atmosphere, radically changing atmospheric chemistry.  Oxygen was toxic to many existing life forms, but eventually micro-organisms capable of using oxygen in the process of respiration evolved, which in time led to the evolution of multicellular organisms (and eventually to us). 

In the case of technosphere evolution, a process that emits excessive amounts of CO2 (combustion of fossil fuels) has arisen, which is altering the global climate and ocean chemistry in a way than may be toxic to many existing life forms.  One potential solution is that the technosphere can further evolve (by way of cultural evolution) to subsist on renewable energy rather than combustion of fossil fuels, thus moderating its influence on the atmosphere, hydrosphere, and biosphere.

A characteristic feature of technosphere evolution is ever more elaborate means of transportation and telecommunications.  These capabilities – especially the on-going buildout of the Internet – allow for increased integration across the technosphere and tighter coupling of the technosphere with the rest of the Earth system.  Sharing results of environmental monitoring in its many dimensions over the telecommunications network can help with creating and maintaining sustainable natural resource management schemes.   

Through the popular news and social media, nearly everyone in the world can learn about events such as regional droughts and catastrophic forest fires that are associated with climate change.  It is thus becoming easier to have a common frame of reference among all humans about the state of the planet.

There is not yet anything like a global consciousness that coordinates across the whole technosphere.  However, the Internet is facilitating the emergence of a global brain type entity.  One indication of what the nascent global brain is thinking about is the relative frequencies of different search terms on Google.  Interestingly, in the algorithms that determine the response to search engine queries, a high frequency of previous usage for a relevant web site makes that site more likely to reach the top of the response list.  That process is evocative of learning, i.e. reinforcement through repetition.  Similarly, the Amygdala Project monitors Twitter hashtags.  They are classified according to emotional tone, and a running visual summation gives a sense of the collective emotional state (of the Twitterers).  Advances in artificial intelligence and quantum computing may soon improve the module in the global brain that simulates the future of the Earth system.

4.  The Expanding Domain of Human Moral Concern

In “The Slow Creation of Humanity”, psychologist Sam McFarland recounts the history of the human rights movement.  Writer H.G. Wells, humanitarian Eleanor Roosevelt, and others have helped develop the rationale and legal basis for including all human beings in our “circles of compassion” (Einstein’s term).  The concept of rights has now begun to be legally extended to Nature (in Ecuador) and specifically to Earth (in Bolivia).  Since protecting the rights of Earth (e.g. to be free of pollution) clearly requires that humans work collectively, we come to an incentive for global human solidarity.

Again, these four unifying factors are only the start of a list that might also include global improvements in education, as well as growth in the activities of global non-governmental environmental organizations. 

Conclusions

The field of Earth system science is producing an increasingly clear understanding of the human predicament with respect to global environmental change.  Scientist know what is happening to the global environment, what is likely to happen in the future under Business-as-Usual assumptions, and to some degree, what must change to avert an environmental catastrophe.

The process of changing the trajectory of the Earth system cannot be done unilaterally.  From the top down, an important step will be genesis or reform of the institutions of global governance – including institutions concerned with the political, economic, and environmental dimensions of governance.  This is a task for a generation of researchers, political leaders, and diplomats.  From the bottom up, individuals must be brought around as adults, and brought up as children, to adopt an identity that includes global citizenship and associated responsibilities for the global environment.  This is a task for a generation of educators, religious leaders, and business leaders.

If “we” human dwellers on Earth don’t gain a collective identity and begin to better manage the course of technosphere evolution, then we may no longer thrive on this planet.

Recommended Audio/Video, Mother Earth, Neil Young