Earth Day 2020

Earth Day 2020 and Global Solidarity

David P. Turner / April 19, 2020

Earth Day in 2020 is the 50th Anniversary for this annual gathering of our global tribe.  Historically, it has been an opportunity to note declines in environmental quality and to envision a sustainable relationship of humanity to the rest of the Earth system.

This year, in addition to the usual concerns about issues like climate change and ocean acidification, Earth Day is accompanied by concern about the specter of the COVID-19 pandemic.  A glance at the geographic distribution of this virus is the latest reminder that interactions with the biosphere, in this case the microbial component, can link all humans in powerful ways. 

Environmental issues that were on the front burner when Senator Gaylord Nelson initiated Earth Day in 1970 were mostly local − polluted rivers, polluted air, and degraded land cover.  These issues were addressed to a significant degree in the U.S. by passage of the Clean Water Act (1972), the Clean Air Act (1970), and the Endangered Species Act (1973).  These were national level successes inspired by environmental activism.

Awareness of global environmental change in 1970 was only dimly informed by geophysical observations such as the slow rise in the atmospheric CO2 concentration.  But by the 1980s, climate scientists began a drumbeat of testimony to governments and the media that the environmental pollution issue extended to the global scale and might eventually threaten all of humanity. 

The United Nations has functioned as a forum for international deliberations about global environmental change issues, and the signing of the Montreal Protocol on Substances that Deplete the Ozone Layer in 1987 hinted at the possibilities for global solidarity with respect to the environment.

To help matters, economic globalization in the 1990s began uniting the world in new ways.  Huge flows in goods and services across borders fueled a truly global economy.  The level of communication required to support the global economy was based on the rapidly evolving Internet.  It provided the foundation for a global transportation/telecommunications infrastructure that now envelops the planet.

A political backlash to economic and cultural globalization has recently brought to power leaders like Donald Trump (U.S.) and Jair Bolsonaro (Brazil).  Their inclination is much more towards nationalism than towards global solidarity on environmental issues.

However, humanity is indeed united – in fear of climate change and coronavirus pandemics if nothing else.

Each year, the growing incidence of extreme weather events associated with anthropogenic climate change negatively impinges on the quality of life of a vast number of people around the planet.  This year, billions of us are locked down in one form or another to slow the spread of a virus that likely emerged from trafficking in wild animals.  In a mythopoetic sense, it is as if Earth was responding to the depredations imposed upon it by our species.

Philosopher Isabelle Stengers refers to the “intrusion” of Gaia (the Earth system) upon human history.  The message from Gaia is that she is no longer just a background for the infinite expansion of the human enterprise (the technosphere). 

Humanity can reply to Gaia with ad hoc measures like building sea walls for protection from sea level rise.  Or we can get organized and develop a framework for global environmental governance.

There are many impediments to becoming a global “we” that will work collectively on global environmental change issues.  Nevertheless, the incentives for doing so are arriving hard and fast.  The diminishment of the wild animal trade in China in response to COVID-19, and the unintended reduction of greenhouse gas emissions globally associated with efforts to slow the spread of COVID-19, signal that radical change is possible. 

Fitting testaments to an emerging global solidarity about environmental issues would be eradication of commercial exploitation of wild land animals everywhere in the world, and stronger national commitments to reduce greenhouse gas emissions relative to current obligations under the Paris Climate Agreement. 

Both initiatives of course face strong cultural and political headwinds.  But Earth Day, as one of the largest recurring secular celebrations in the world, is an opportunity to think anew.

Recommended audio/video:
One World (Not Three), The Police
https://www.youtube.com/watch?v=N0U-IaURsGM

Ocean Photosynthesis May Be Decreasing

My previous blog post noted that global land photosynthesis is clearly increasing in recent decades.  However, when we turn to the ocean, the story is different (albeit more ambiguous).

About half of global photosynthesis takes place in the ocean.  Much of the resulting biomass production (net primary production) is consumed, thus supporting a food web that includes large marine animals like fish and whales.  Billions of people eat wild caught ocean fish each day as a source of protein.

Photosynthesis in the ocean is frequently constrained by nutrient availability.  Hence, areas where photosynthesis is high are often where upwelling brings nutrient-rich deep water to the surface, or runoff from the land includes nutrients. 

Earth system scientists now monitor global ocean photosynthesis using a combination of satellite remote sensing, direct measurements, and modeling.  As always with global scale processes, there is significant uncertainty about the estimates and some regions show increasing net primary production (NPP) while other regions show decreases.  Various studies have reached differing conclusions about trends in the global total, but a recent study suggested that ocean NPP is in decline (1998 – 2015).

Figure 1.  Trend in ocean primary production.  Estimates are based on a biogeochemical model (coupled to a full ocean model) that assimilates ocean color satellite data. 

Oceanographers are beginning to get an understanding of what is driving the decline.

A key factor appears to be reduced delivery of nutrients to the ocean’s surface.  The causes are related to global warming, a process driven by rising concentrations of greenhouse gases in the atmosphere. 

An important mechanism that is slowing delivery of nutrients to the surface ocean is an increase in stratification associated with the general warming of ocean surface waters.  A cap of warm water tends to reduce vertical mixing, which in turn reduces recharge of surface nutrients from deeper waters where much decomposition and nutrient release takes place.

Figure 2.  Trend in ocean mixed layer depth.  Estimates are based on a global physical three-dimensional model of the ocean driven by geophysical observations.

Another process related to nutrient supply involves the cycling of water from the surface to the deep ocean and back to the surface (the thermohaline circulation).  The descending arm of this Earth-girdling loop of ocean circulation is based on warm water brought north by the Gulf Stream.  That water cools, densifies, and sinks in the North Atlantic Ocean and eventually returns to the surface elsewhere bringing with it nutrients from the deep ocean.  Recent measurements suggest a weakening of that descending arm cause by a freshening of North Atlantic waters driven mostly by melting of the Greenland ice cap.

A decline in ocean photosynthesis − the base of the ocean food chain − likely translates into lower fish production.  Fisheries all over the planet are already under stress from many factors, not least of which is overharvesting.  Ocean warming causes decline of coral (a source of NPP), ocean acidification reduces NPP of calcifying plankton, decreases in ocean oxygen from reduced mixing and excess nutrient runoff (coastal dead zones) force fish to migrate, and toxic waste inputs (including macro-, micro-, and nano- plastics) reduce feeding efficiency.  After decades of fish harvest increases, the global catch peaked in the 1990s.  Model-based projections of ocean animal biomass suggest continuing declines with further ocean warming.

Despite the immensity of the ocean, human impacts on it are piling up.  A new narrative about ocean management is needed.

We (as a part of the technosphere) cannot directly change ocean circulation in an attempt to restore declining primary production and fish production.  We can only slow the emissions of greenhouse gases, which would slow global warming and its associated impacts on ocean mixing and circulation.  Stabilizing, then reducing, the atmospheric CO2 concentration would also slow ocean acidification.

The time is now to support leaders who understand the realities of global environmental change and are committed to working domestically and internationally to implement policies that change the current trajectory of the Earth system.

The Icarus Scenario


Jacob Peter Gowy’s The Flight of Icarus (1635–1637), courtesy of Prado Museum

David P. Turner / February 26, 2020

The future invades the present much more so in recent times than was the case in previous generations.  That’s because the global human enterprise (the technosphere) has initiated an era of global climate change – with potentially catastrophic impacts on future generations.  Thus, humans must now worry more about the future than might otherwise be the case.  While we still have time, humanity must alter course – we must redesign the technosphere.

Earth system scientists have a responsibility to discern coming changes to the Earth system as clearly as possible, and to evaluate potential mitigation strategies.  The time horizon of these scenarios for global change are commonly on the order of a century, or perhaps several centuries.  But examining scenarios that play out over hundreds to thousands of years is also necessary.

In the course of writing a book about global environmental change, I developed a rather dystopian long-timeframe Earth system scenario.  I call it the Icarus Scenario.  This story of Earth’s future is based on emerging Earth system science knowledge about past episodes of drastic global change over the course of geologic history.  On multiple occasions, tectonic movements have initiated periods of massive greenhouse gas emissions (sound familiar?) that led to strong global warming, followed by major alterations in ocean circulation and chemistry, as well as profound changes in the biosphere (including mass extinction events in some cases). 

Humanity might now be initiating the next iteration of that sequence, and the Icarus myth seems an appropriate referent.  Icarus was the figure from Greek mythology who, with his father, constructed wings of feathers and wax.  His father warned him not to fly too close to the sun for fear of melting the wax, but Icarus got carried away with the joy of flight.  He indeed flew too close to the sun, his wings disintegrated, and he crashed to his death on the ground.

A contemporary version of this myth might be manifest as the on-going build-out of the technosphere (with associated greenhouse gas emissions), warnings by scientists about the possibility of overheating the planet, continued fossil-fuel-based technosphere growth driven by an exuberant market economy, and global warming sufficient to push the Earth system through a series of tipping points that catastrophically warm the planet.  Recent geophysical observations suggest the risk of initiating that sequence is increasing.

We can’t of course know the future.  But there are several compelling reasons why we as a global collective should grapple with the Icarus Scenario.

It is likely that the wealthiest people in the world will be able to largely insulate themselves from impacts of climate change over the next generation or so.  Consequently, supporting societal investment in mitigation climate change (e.g. the Green New Deal) may not be a high priority.  However, if their legacy will amount to nothing in a somewhat longer perspective, they might pitch in more vigorously (thanks Jeff Bezos!).

The Icarus Scenario also strengthens the rationale for investing in climate change mitigation as soon as possible to reduce the possibility of passing a threshold and being unable to reverse the trajectory of the Earth system towards catastrophic warming.  The precautionary principle is more readily invoked as the magnitude of a threat increases, and the Icarus Scenario is the ultimate threat.

Being an inveterate optimist, I also formulated in my book a long-term Earth system scenario in which the technosphere builds a sustainable relationship with the rest of the Earth system.  My Noösphere Scenario (pronounced like noah-sphere) assumes cultural evolution towards a high technology global civilization that self-regulates to avoid overheating the planet and consuming the biosphere.  The root word nous refers to mind – Earth becomes a planet organized by collective thought.

Growth of the Technosphere

David P. Turner / January 28, 2020

The growth of the technosphere is changing the Earth system, pushing it towards a state that may be inimical to future human civilization [1].  As technosphere capital − e.g. in the form of buildings, machines, and electronic devices – is increasing, biosphere capital −in the form of wild organisms and intact ecosystems − is decreasing [2].

Figure 1.  Decline in freshwater, marine and terrestrial populations of vertebrates.  Adapted from Ripple et al. 2015 [3].

The growth of the technosphere has tremendous momentum and we must ask if it can be shaped and regulated into something that is sustainable, i.e. able to co-exist with the rest of the Earth system over the long term.

Figure 2.  Earth system indicator trends 1750-2010.  Adapted from Steffen et al. 2015 [4].

Why is the technosphere growing so vigorously?  Let’s consider three quite different factors. 

1.  The most general driver of technosphere growth is what systems ecologist Howard Odum called the “maximum power principle”.  It states: “During self-organization, system designs develop and prevail that maximize power intake, energy transformation, and those uses that reinforce production and efficiency” [5].   Self-organization is a widely observed phenomenon, extending from the funnel of water formed in a draining bathtub, to inorganic chemical reactions that create arresting geometric designs, to giant termite mounds, and indeed, to cities [6].  Given Earth’s vast reservoirs of fossil fuel energy, and a selection regime that rewards growth, the technosphere will indeed tend to increase energy consumption, matter throughput, and complexity. 

2.  Underlying much of the momentum of technosphere growth is the global market economy.  Capitalism is essentially the operating system of the technosphere.  Corporations, the state, and workers are compelled to expand the economy and hence the technosphere [7]. 

The market economy rewards increasing efficiencies in production (to reduce costs) and often the route to greater efficiently and greater economies of scale is by investment in technology.  Technical progress is now the expected norm and investments in research and development are a part of corporate culture and national agendas.  Economists refer to the “treadmill of production” in which “competition, profitability, and the quest for market share has contributed to an acceleration of human impact on the environment” [8].  Economic globalization has geographically extended the market economy to the whole world.

3.  Historically, war has been one of the biggest drivers of technological expansion.  In the Parable of the Tribes, historian Andrew Schmookler describes the sustained pressure on societies to conquer or be conquered [9].  Technology advances certainly help in winning wars and national governments invest heavily in research and application of technologies for war.  The Internet began with U.S. Defense Department funding to build a communications infrastructure that was hardened against nuclear attack.

Humanity has of course benefited broadly as the technosphere expanded.  Billions of people now have standards of living rivaling those of royalty a few hundred years ago.  The proportion of the global population living in poverty continues to decline.

But even before the use of the term technosphere, scientists and philosophers had begun to question whether technology was always a benevolent force.  The concept of “autonomous technology” suggests that the growth and elaboration of technology can escape human control [10, 11].  The possibilities for a nuclear holocaust or a greenhouse gas driven climate change catastrophe are indicative of technology-mediated global threats. 

What can be done?

The maximum power principle does promote energy throughput, but there is plenty of scope for insuring that technosphere energy prioritizes renewable energy.  Carbon taxes may be the simplest approach to rapidly driving down fossil fuel combustion.  Comprehensive recycling, based on a circular economy, will help constrain the mass throughput of the technosphere.  Finishing the global demographic transition [12] will reduce future demand for natural resources.

Capitalism will not go away but could undergo a Reformation.  That means more corporate responsibility, better governmental oversight of corporate behavior, and increased attention by consumer to the environmental footprint of their consumption.

The global incidence of physical war is decreasing, which will help slow the growth of the technosphere.  Wars are often based on the threat of an enemy, but humanity may become more unified based on the common threat of global environmental change.  The Paris Accord is suggestive of the possibilities.

Implications

The trajectory of the technosphere is towards limitless growth.  However, we live on a planet – there are indeed limits to the natural resources upon which the technosphere depends.  Humans are only a part of the technosphere, thus cannot truly control it (13).  But they can certainly shape it .  Likewise, the technosphere is only part of the Earth system, thus cannot fully control the Earth system: quite possibly, the Earth system will respond to the environmental impacts of the technosphere with changes that suppress the technosphere and associated human welfare.  Improved understanding of technosphere growth in the context of the rest of the Earth system is clearly warranted.

1.  Steffen, W., et al., Trajectories of the Earth System in the Anthropocene. Proceedings of the National Academy of Sciences of the United States of America, 2018. 115(33): p. 8252-8259.

2.  Diaz, S., et al., Pervasive human-driven decline of life on Earth points to the need for transformative change. Science, 2019. 366(6471): p. 1327-+.

3.  Ripple, W.J., et al., World Scientists’ Warning to Humanity: A Second Notice. Bioscience, 2017. 67(12): p. 1026-1028.

4.  Steffen, W., et al., The trajectory of the Anthropocene: The Great Acceleration. The Anthropocene Review, 2015. 2: p. 81-98.

5.  Odum, H.T., Self-Organization and Maximum Empower, in Maximum Power: The Ideas and Applications of H.T. Odum. 1995, Colorado University Press: Boulder CO.  See Hall review.

6.  Prigogine, I. and I. Stengers, Order out of Chaos. 1984: Bantam.

7.  Curran, D., The Treadmill of Production and the Positional Economy of Consumption. Canadian Review of Sociology-Revue Canadienne De Sociologie, 2017. 54(1): p. 28-47.

8.  Hooks, G. and C.L. Smith, Treadmills of production and destruction – Threats to the environment posed by militarism. Organization & Environment, 2005. 18(1): p. 19-37.

9.  Schmookler, A.B., The Parable of the Tribes: The Problem of Power in Social Evolution, Second Edition 1994: Suny Press. 426.

10.  Winner, L., Autonomous Technology: Technics-out-of-Control as a Theme of Political Thought. 1978: The M.I.T. Press. 402.

11.  Kelly, K., Out of Control: The New Biology of Machines, Social Systems, & the Economic World. 1995: Basic Books.

12.  Bongaarts, J., Human population growth and the demographic transition. Philosophical Transactions of the Royal Society B-Biological Sciences, 2009. 364(1532): p. 2985-2990.

13.  Haff, P.,  Humans and technology in the Anthropocene: Six rules. 2014. The Anthropocene Review:126-136.

The Second Revival of Gaia

January 11, 2020/David P. Turner

Gaia was originally a figure from Greek mythology: the mother goddess who gave birth to the sky, the mountains, and the sea.  Gaia was adopted by the Romans when they conquered the Mediterranean basin, but her myth was largely abandoned with the ascendency of Christianity by the third century CE.

The first revival of Gaia was a product of the nascent Earth system science community in the 1970s.  Atmospheric chemist James Lovelock was impressed by the finding of geologists that life had persisted on Earth for over 3 billion years despite a 25% increase in the strength of solar radiation (associated with an aging sun), and numerous catastrophic collisions with asteroids.  He also understood that the chemistry of the atmosphere − which provides oxygen for animal respiration, protection from toxic solar UV-B radiation, and influences the global climate − was maintained by the metabolism of the biosphere. 

These observations led him to suggest that the Earth as a whole was in a sense homeostatic, it was able to maintain certain life enhancing properties in the face of significant perturbations.    

In casting around for a name to give this organism-like version of the planet, he was inspired by author William Golding to revive the term Gaia.  Lovelock and microbiologist Lynn Margulis went on to write many influential peer-reviewed papers, and later books, on Gaia.

By the 1990s, the question of what regulated the functioning of the Earth system had become of more than academic interest.  Earth system scientists had observed that the Earth system was changing and begun to worry about possible impacts of those changes on the human enterprise.  Concentrations of greenhouse gases were rising, stratospheric ozone was declining, and a wave of extinctions was sweeping the planet. 

Geoscientists were initially intrigued by the Gaia Hypothesis about planetary homeostasis, hoping perhaps that Gaian homeostasis might save us from ourselves.  But by around 2000 they had largely rejected Gaia as an entity.  Many of the feedbacks in the Earth system (see my Teleological Feedback blog) were positive (amplifying climate change) rather than negative (damping), hence not contributing to homeostasis.

The second revival of Gaia came predominantly from scholars in the humanities.  Historians typically begin human history about 10,000 years ago when humans adopted an agricultural way of life.  However, the discovery that humans have recently begun to alter the global environment on a geologic scale changes everything (as activist Naomi Klein says).  The Earth system is no longer a benevolent background state that will provide a growing humanity with unlimited resources.  Earth has a Gaian history that is now imposed upon by human history.  The new field of Big History aims to juxtapose the geologic and anthropocentric time frames.

Historians needed a term to evoke an Earth system that in a sense has its own agency, and scholars like science historian Bruno Latour and philosopher Isabelle Stengers settled on Gaia.  They emphasized Gaia not as a nurturing mother, but rather a force that will smack humanity down if the current trajectory of global environmental change continues.

In a recent hybrid interpretation, geoscientist Tim Lenton and humanities scholar Bruno Latour have dubbed the newly revived Gaia as Gaia 2.0.  This version refers to an Earth system on which a sentient species has evolved and begun to alter the planet but has collectively taken on the project of developing an advanced technological civilization (a technosphere) that will live on the planet sustainably.  That means comprehensive renewable energy, nearly closed material cycling, conservation of biodiversity to support the background metabolism of Gaia 1.0, implementation of multiple strategies to moderate climate change, and forms of governance that facilitate self-regulation at multiple scales.

Gaia 2.0 is the combination of the pre-human Gaian Earth system and the recently emergent technosphere.

The Teleological Feedback

January 6, 2020/David P. Turner

Earth system scientists commonly refer to feedbacks in the climate system. 

A feedback loop within a system means that a change in one part or component of the system induces a change in another component that either amplifies (positive feedback) or dampens (negative feedback) the initial change. 

The classic positive feedback related to global climate change and the Earth system is that warming of the global climate caused by increasing greenhouse gas concentrations in the atmosphere results in reduction in snow cover and sea ice, which causes less reflectance of solar radiation, and hence more absorption of solar radiation by Earth’s surface, and more warming.  A potential negative feedback is if warming increases evaporation, which causes more clouds, which reflect more solar radiation, and hence cool the climate.  Most of the feedbacks in the climate system are positive.

By burning fossil fuels and pushing up the atmospheric CO2 concentration, humanity is unintentionally warming the global climate and inducing multiple climate system feedbacks.

A big question is whether humanity can collectively begin to purposefully impact the Earth system in the form of a negative feedback to climate change, i.e. begin to slow down the rise in greenhouse gas concentrations and even begin to draw down those concentrations.  This willful action would be a teleological feedback to our unintended warming of the Earth system by way of greenhouse gas emissions.

Teleological feedback. The segmented line indicates the potential for a deliberate societal influence on the Earth system.

A disturbing paradox about current climate change is that by increasing the atmospheric CO2 concentration, humanity has shown that we are the equivalent of a geological force.  But humanity thus far is not organized enough to purposefully shape the Earth system. 

What we don’t have is much political will to reduce greenhouse gas emissions, nor the right international institutions to manage a global scale response. 

Political will comes from lots of sources, but maybe the most likely source is that as more and more people experience extreme weather events, sea level rise, and the other impacts of climate change, they will support mitigation efforts (e.g. a carbon tax).  Australia in 2020 appears to be a test case for this proposition.

Also, we might hope for political leaders who understand the situation and are committed to doing something about it.

Regarding global environmental governance, the size and strength of relevant international institutions are incommensurate with the challenge of global environmental change.  At the very least, a stronger United Nations Environmental Program or a new U.N. World Environmental Organization is needed.

Recommended Reading

Lenton, T. 2016. Earth System Science: A very short introduction. Oxford University Press.

Recommended Audio/Video

Joni Mitchell, They Paved Paradise

Discovery of the Technosphere

Earth System Science Discovery of the Technosphere

January 5, 2020/David P. Turner

The field of Earth System Science is a relatively young and is still working out how best to characterize Earth’s parts.  A key difficulty is with including the human dimension in a comprehensive description of the contemporary Earth system.  Earth scientists like to think in terms of the Earthly spheres and their interactions, e.g. the geosphere, atmosphere, hydrosphere, and biosphere.  By way of its industrial might, the global human enterprise recently has begun to exert an influence on the Earth system that is the equivalent to one of these spheres – effectively we have become a “geologic force”.  One proposal for characterizing this newly evolved global scale presence is to call it the “technosphere”.

To gain an appreciation for the meaning of technosphere, it helps to draw an analogy to the term biosphere.  We consider the biosphere to consist of all life on Earth.  It lives on energy, mostly in the form of solar radiation that is converted to biomass by photosynthesis, and it has a throughput or cycling of mass, mostly in the form of carbon and essential nutrients.

The Earth system existed before the origin of life and the evolution of the biosphere.  But once in place, the biosphere began exerting a strong influence on the chemistry of the atmosphere and the ocean, as well as on the global climate. 

Likewise, the technosphere is a globe-girdling network of artifacts −including all machines, buildings, and electronic devices – that lives on energy, mostly derived from fossil fuels, and has a throughput of mass (food, fiber, minerals).  The technosphere is growing rather irrepressibly, and like the biosphere before it, has begun to alter the global climate.

In a systems-oriented worldview, we try to differentiate parts and wholes, and to understand their relationship.  Generally, a part does not control the whole.  Thus, a critical feature of the technosphere is that humans are only a part of it, and correspondingly humanity cannot fully control it.  The technosphere is said to have agency, its own agenda.  It thrives on ever greater flows of energy and mass, which is not surprising when you realize that capitalism is its operating system.

Now that Earth system science has “discovered” the technosphere, we can study its structure, properties, dynamics, and how it interacts with the rest of the Earth system.  An awareness that we serve the technosphere as much as it serves us may help us redesign and rebuild it in a way that makes a human-occupied Earth system more sustainable.

Recommended Reading

Earth’s ‘technosphere’ now weighs 30 trillion tons

Zalasiewicz, J., et al. 2017. Scale and diversity of the physical technosphere: A geological perspective. Anthropocene Review. 4:9-22.

Will Steffen , Katherine Richardson, Johan Rockström, Hans Joachim Schellnhuber, Opha Pauline Dube, Sébastien Dutreuil, Timothy M. Lenton and Jane Lubchenco. 2020. The emergence and evolution of Earth System Science. Nature Reviews, Earth and Environment, January 2020).

Haff, P. 2014. Humans and technology in the Anthropocene: Six rules. Anthropocene Review. 1:126-136.

Recommended Video

Daily world air traffic

Daily world air traffic

Posted by The EARTH on Friday, May 12, 2017

Recommended Audio/Video

Bruce Cockburn, If a Tree Falls