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The Anthropocene


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A presentation on the paper, "The Anthropocene: Conceptual and historical perspectives" by Steffen et. al.

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The Anthropocene

  1. 1. The Anthropocene Conceptual and historical perspectives Will Steffen, Jacques Grinevald, Paul Crutzen, John McNeill Philosophical Transactions of the Royal Society A (2011) 369, 842-867
  2. 2. Journey through history – evolution of anthropocene Attempt to answer (with statistics and graphs) - Can human activity really be significant enough to drive the Earth into a new geological epoch? Argument about what the logical start date for this new epoch should be = advent of Industrial Revolution around 1800? Recent trends of the 21st century abstract Paper = case for formal recognition of “Anthropocene” as a new epoch in Earth history Concept of anthropocene; emergence of anthropocene discourse
  3. 3. i.Ozone hole = anthropogenic cause ii.Changes in the carbon cycle, biogeochemical or element cycles (nitrogen, phosphorus, sulphur, etc.), hydrological cycle = all anthropogenic cause iii.6th major extinction event in Earth history will thence be – anthropogenic cause Earth is now moving out of its current Holocene epoch Human activity is largely responsible, making humankind a global geological force in its own right The term is still informal The “Anthropocene” Anthropos (Greek) = human Anthropogenic causes catalysing drastic environmental changes, rivalling even the very forces of Nature –
  4. 4. Anthropogenic transformation of the biosphere into the “noösphere”/ “anthroposphere”. (Suess, E. La Face de la Terre. French publication. Paris, early 1920s. Last volume) Noösphere – based on Greek ‘noos’ (= mind) – a postulated sphere or stage of evolutionary development dominated by consciousness, the mind and interpersonal relationships. Prophesying the inception of “Anthrocene” (Revkin, C.A. 1992. Global Warming) Proposal of the “Anthropozoic era” (a noted Italian geologist and Catholic priest) Talks of “technosphere” and the more recent “industrial metabolism” The “psychozoic era” – the era of reason (Vernadsky, V. Carbon and living matter in the earth’s crust. Geochemistry. 28, p. 66) Influence of consciousness and collective human reason upon geochemical processes Man acting as Homo sapiens faber : i.Exerting influence on elements necessary for technology and creation of civilized forms of life ii.Modifying natural ecosystems to gain advantage precursors
  5. 5. Few million years ago – humans modifying (but never fully transforming) natural ecosystems to gain advantage or help in hunting and food gathering Started with Homo erectus learning to control and manipulate fire Humans with the largest brain-to-body ratio -> accumulation of knowledge and social learning -> complex civilizations -> increased power to manipulate environment First pre-industrial significant human use of coal (fossil fuel) – [Song Dynasty, 960-1279, China] The Great Acceleration – the post-World War II worldwide industrialization, techno-scientific development, nuclear arms race, population explosion, rapid economic growth … A Journey through history – Evolution of the Anthropocene
  6. 6. “…In thousands of years, when, seen from the distance, only the broad lines of the present age will still be visible, our wars and our revolutions will count for little, even supposing they are remembered at all; but the steam engine, and the procession of inventions of every kind that accompanied it, will perhaps be spoken of as we speak of the bronze or the chipped-stone of pre-historic times: it will serve to define an age.” Bergson, H. 1907. L’Evolution Créatrice
  7. 7. The early Anthropocene hypothesis Two pre-industrial events heralding the beginning of anthropocene – i.Extinction of Pliestocene megafauna – close correlation between the timing of the extinction and the arrival of humans ii.Neolithic Revolution (advent of agriculture) – emitting enough CO2 and CH4 to prevent the initiation of the next ice age Early forest clearing reversed the downward trend in CO2 concentration. Earth is currently in an unusually long interglacial period and is not due to enter another ice age for at least 10,000 years (without any increases in greenhouse gas emissions). Recent analysis – the early Anthropocene hypothesis does not seem plausible; does not have widespread support
  8. 8. Industrial Revolution [origin in Great Britain in 1700s or thermo-industrial revolution of 19th century Western civilization] – end of agriculture as the most dominant human activity i.A world dominated by a growing energy bottleneck (Earth's energy sources tightly constrained in magnitude and location) ii.Discovery (and exploitation) of fossil fuels shattered the bottleneck iii.Haber-Bosch process synthesizing reactive nitrogen compounds from unreactive nitrogen in the atmosphere – creating fertilizer out of air iv.Conversion of natural ecosystems – large dams diverting water from rivers The start of something new – the Anthropocene begins
  9. 9. 1800 – 2000: Human population grew from 1 billion to 6 billion Energy use grew about 40-fold Economic production grew 50-fold Therefore, submission for the start date – 1800 AD could reasonably be chosen as the beginning of the Anthropocene.
  10. 10. Post-World War II trajectory: oExplosions in mobility – Automobile, Aeroplane oGlobalisation, global economy – mines and plantations oNew international institutions oNeo-liberal economic principles, open trade and capital flows, market economy oSpectrum of new technologies oPartnerships among government, industry and academia The Great Acceleration: Onset delayed by a half-century or so, interrupted by the two World Wars and the Great Depression. The Great Acceleration (1945 – 2000+)
  11. 11. Earth system clearly outside the envelope of Holocene variability •Population increased from 3 to 6 billion in just 50 years •Economic activity increased 15-fold in those 50 years •Widespread abandonment of the farm and village for city life – over half the human population (3 billion) living in urban areas •Human-dominated landscapes •Global environmental problems neglected – Rise in greenhouse gas concentrations, dramatic increase in reactive nitrogen, episodes of acid rain, CO2 concentrations increase by an astounding 58 ppm. World is likely entering its 6th great extinction event and the first caused by a biological species.
  12. 12. •Developing countries account for 20% of total emissions (since 1751) but contain about 80% of the world’s population. •World’s poorest countries (with a combined population of ~ 800 million) have contributed less than 1% of cumulative CO2 emissions (since Industrial Revolution) •Over 90% of growth in coal use = China (largest emitter of CO2) and India (third-largest emitter) •Potential resource constraints – i.Peak oil – the maximum rate of production of oil in a particular area, aware that it is a finite resource and subject to depletion = diminishing petroleum supplies ii.Peak phosphorus – increase in population will eventually peak phosphorus demand = deteriorating food security 21st Century Anthropocene
  13. 13. •Genetics and Molecular biology - accelerating drive to not only understand molecular and genetic basis of life, but to synthesize life itself Craig Venter (mapping the human genome) Miller & Urey (synthesizing complex organic molecules from simple inorganic molecules in the primitive Earth atmosphere) •Failure to slow the recent decline in Earth’s biodiversity – decline in vertebrates population, forest cover, condition of coral reefs
  14. 14. •Growing awareness of human impact on environment •Attempts at global governance (UNFCCC, CBD, etc.) •Irreversibility – loss of species can’t be reversed if society after the fact decides they might be valuable/worth preserving •Magnified equity issues (wealthy countries that pollute vs poorest countries that suffer) •Complexity of the Earth system functioning problematic for policymakers •Innovative approaches Active adaptive management Multi-level and polycentric governance systems Steffen et al – Humanity now entering Stage 3 of Anthropocene
  15. 15. oBuild early warning systems for change oEnhance prediction of the Earth system behaviour oEnhance capacity to assimilate new information to analyse, interpret, and model complex system dynamics. oGeo-engineering – artificially adding aerosols into the stratosphere (adverse environmental side-effects? – Snowpiercer) oCalculations indicate a delay by several decades in the recovery of ozone hole (Tilmes et al.) oGrowing uptake of CO2 will lead to acidification of the upper ocean waters (oceans = naturals CO2 sinks), which in turn will lead to dissolution of calcifying organisms oSulphur particle concentration in the stratosphere will change precipitation regimes around the world, affecting global hydrological cycle Looking to the future… the Anthropocene ensues
  16. 16. 1.Antithesis of geo-engineering – the planetary boundaries concept •-based on returning the Earth system to the Holocene domain •-defines the ‘safe operating space’ for humanity with respect to the Earth system 1.Climate scepticism – the denial of contemporary climate change and/or its human cause 2.Cognitive dissonance – when facts that challenge a deeply held belief are presented, the believer clings more strongly to his/her beliefs 3.Concept of the Anthropocene threatens the viability of contemporary civilization (and perhaps even the future existence of our species) On a Concluding Note: Public perception
  17. 17. Thank you. Bedashree Choudhury M.Sc. WSG 14109MWS