The Anthropocene
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Transcript of The Anthropocene
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
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
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 –
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
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
“…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
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
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
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.
Post-World War II trajectory:
o Explosions in mobility – Automobile, Aeroplane o Globalisation, global economy – mines and plantations o New international institutions o Neo-liberal economic principles, open trade and capital flows, market economy o Spectrum of new technologies o Partnerships 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+)
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.
• 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
• 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
• 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
o Build early warning systems for change o Enhance prediction of the Earth system behaviour o Enhance capacity to assimilate new information to analyse, interpret, and model
complex system dynamics. o Geo-engineering – artificially adding aerosols into the stratosphere (adverse
environmental side-effects? – Snowpiercer) o Calculations indicate a delay by several decades in the recovery of ozone hole
(Tilmes et al.) o Growing 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 o Sulphur particle concentration in the stratosphere will change precipitation
regimes around the world, affecting global hydrological cycle
Looking to the future… the Anthropocene ensues
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
Thank you.
Bedashree Choudhury M.Sc. WSG 14109MWS