Tag Archives: tipping points

The Technosphere is Melting the Cryosphere

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Iceberg in Lilliehöökfjord, Svalbard.  Image credit: Hannes Grobe, CC BY-SA 4.0

David P. Turner / February 1, 2021

Earth system scientists think of planet Earth as composed of multiple interacting spheres.  The cryosphere is a term given to the totality of frozen water on Earth – including snow, ice, glaciers, polar ice caps, sea ice, and permafrost.

The cryosphere has a significant effect on the global climate because snow and ice largely reflect solar radiation, hence cooling the planet.

Unfortunately, the cryosphere is melting.  That loss of snow and ice is providing a significant positive (amplifying) feedback to anthropogenically induced global warming.

Over the course of Earth’s geological history, the cryosphere has existed as everything from nearly 100% coverage of the planetary surface around 700 Mya (million years ago) i.e. snowball Earth (Figure 1) to virtually disappearing during the Hothouse Earth period (about 50 Mya).

Figure 1. Snowball Earth.  The planet was nearly covered in snow and ice around 700 million years ago.  Image Credit: NASA.

The multiple glacial-interglacial cycles over the last several million years were initiated by changes in sun/earth geometry (the Milankovitch cycles), but strengthened by changes in snow/ice reflectance along with changes in greenhouse gas concentrations.

Figure 2.  Ice cover (black) shifted markedly between the glacial and interglacial periods over the last 3 million years.  Image credit:  Hannes Grobe CC Attribution 3.0

The culprit in the current melting of the cryosphere is something new to the Earth system – the technosphere.  This recently evolved sphere consists of the totality of the human enterprise on Earth, including its myriad physical objects and material flows.

By way of fossil fuel combustion, the technosphere is driving up the concentrations of greenhouse gases in the atmosphere and correspondingly, warming the global climate.  That new heat is causing reduced snow cover, receding glaciers, melting of ice caps, and loss of sea ice.  By various anthropogenically driven mechanisms, the cryosphere is also said to be “darkening” and hence melting quicker because more solar radiation is absorbed.

Projections by Earth system models of cryosphere condition over the next decades, centuries, and millennia suggest it will significantly wane if not disappear.

Besides the positive feedback to climate change by way of reflectance effects (and release of greenhouse gases from permafrost melting), the diminishment of the cryosphere will have profound impacts on the technosphere.

  1.  The circulation of water through the hydrosphere on land is regulated in many cases by accumulation of snow and ice on mountains.  That water is subsequently released throughout the year, thus providing stable stream flows for downstream irrigated agriculture and urban use. 
  2. The melting of glaciers and the polar ice caps will drive up sea level.  If all such ice is melted (over the course of hundreds to thousands of years), sea level is projected to rise 68 m.  The magnitude of sea level rise projected over the next 100 years for intermediate emissions scenarios is on the order of one meter.
  3. It remains controversial, but reduction of snow and ice cover may alter the behavior of the jet stream and could induce more extreme weather events in mid- to high latitudes of the northern hemisphere.

Efforts to reduce greenhouse gas emissions will certainly slow the erosion of the cryosphere and should be made.  The precautionary principle suggests we avoid passing tipping points associated with melting of the Greenland ice cap and the Antarctic ice cap.  However, the momentum of environmental change is strongly in that direction.

Once these ice caps are gone, there is a hysteresis effect such that the ice does not return with a simple reversion to the current climate (e.g. by an engineered drawdown of the CO2 concentration).

The planet is headed towards a warmer, largely ice free, condition.  The biosphere has been there before.  The technosphere has not.  Humanity will be challenged to develop adequate adaptive strategies.

Recommended Video: What is the Cryosphere │How it Affects Climate Change

The Icarus Scenario

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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.

Recommended Audio: Epilogue from Everest motion picture (Dario Marianelli)

Growth of the Technosphere

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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.