200 likes | 653 Views
All You Wanted To Know About The Gaia Theory. Pietro Paolo Bertagnolio 23 January 2008 Proseminar Presentation Techniques. Gaia is NOT (only) a goddess. FACTS: Chemical Disequilibrium, Time Records, Daisyworld. HYPOTHESIS: “ The Earth System actively
E N D
All You Wanted To Know About The Gaia Theory Pietro Paolo Bertagnolio 23 January 2008 Proseminar Presentation Techniques
Gaia is NOT (only) a goddess. FACTS: Chemical Disequilibrium, Time Records, Daisyworld HYPOTHESIS: “The Earth System actively (Gaia Hypothesis) self-regulates.” PARADIGM: “The Earth is like (Gaia Theory)a livingbeing.” RESEARCH: Feedback loops, (Geophysiology) Self-regulation mechanisms All You Wanted To Know About Gaia
The History of Gaia • 1785: James Hutton (the “father of geology”) the Earth as a superorganism. • 1927: Vladimir Vernadsky the biosphere drives geological evolution. • 1966: Lynn Margulis the cells are communities of once-independent microorganisms (endosymbiosis) • 1979: James Lovelock“Gaia: A new look at life on Earth”. All You Wanted To Know About Gaia
Living planets, dead planets From Lovelock (1990) All You Wanted To Know About Gaia
Defined boundary: Atmosphere Constant properties: Oxygen conc. Ocean salinity Surface temperature Defined boundary: Membrane Constant properties: pH Osmotic pressure Ionic charge What do they have in common? HOMEOSTASIS All You Wanted To Know About Gaia
Homeostasis and Daisyworld From Olbers (2001) All You Wanted To Know About Gaia
Homeostasis and Daisyworld From Lenton (1998) All You Wanted To Know About Gaia
Homeostasis and Earth From Lovelock (1990) O2 and CH4 are produced by bacterial metabolism. Could these be the Earth’s “daisies”? All You Wanted To Know About Gaia
Definition of Paradigm Scientists develop problems, theories, models and experiments in a given frame, called paradigm. At the core of each paradigm there is often an analogy. Thomas S. Kuhn (1922 - 1996) From Kuhn (1962) All You Wanted To Know About Gaia
Examples of Paradigm (1) ≈ The universe is like Earth-centered spheres Sun-centered spheres an infinite space All You Wanted To Know About Gaia
Examples of Paradigm (2) ≈ is like microscopic particles Light microscopic waves a quantum wavefunction All You Wanted To Know About Gaia
Gaia as a paradigm ≈ The Earth system is like an electronic circuit a living being All You Wanted To Know About Gaia
DMS cycle: Main characters Clouds Phytoplankton Dimethylsulfide (DMS) Dimethylsulfonio propionate All You Wanted To Know About Gaia
DMS cycle: CLAW From Charlson et al. (1987) All You Wanted To Know About Gaia
DMS cycle: Anti-CLAW From Charlson et al. (1987) All You Wanted To Know About Gaia
Summary • Lovelock speculates that the Earth system could have some self-regulating mechanisms. (Gaia hypothesis) • This leads to investigate the Earth system as it was a living organism. (Geophysiological paradigm) • New research has been stimulated by this new way to look at the Earth. (DMS cycle - CLAW hypothesis) All You Wanted To Know About Gaia
That‘s all, folks! References: • Charlson, R. J., Lovelock, J. E., Andreae, M. O., and Warren, S. G., (1987), Oceanic phytoplankton, atmospheric sulphur, cloud albedo and climate. Nature 326, 655-661. • Kuhn, T. S. (1968), The structure of scientific revolutions, University of Chicago Press. • Lenton, T. M. (1998), Gaia and natural selection, Nature 394, 439-447. • Lovelock, J. E. (1990),The Ages of Gaia, Bantam Books. • Olbers, D. (2001), A gallery of simple models from climate physics, Stochastic Climate Models, Progress in Probability, 49, 3-36. All You Wanted To Know About Gaia