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GEOPHYSIOLOGY: FROM PASTEUR AND HUTTON VIA
VERNADSKY, REDFIELD TO LOVELOCK.
2) THE BIOSPHERE, CLIMATE STABILISATION, LOVELOCK AND
DAISYWORLD
A) HISTORY OF THE DEVELOPMENT OF THE CONCEPT OF GLOBAL
PHYSIOLOGY
1600 - Giordano Bruno – suggested extraterrestrial life Brought to the
Campo de' Fiori, a central Roman market square, his tongue in a gag,
hung upside-down naked and burned at the stake, on February 17, 1600.
At his trial, he said: "Perhaps you, my judges, pronounce this sentence
against me with greater fear than I receive it.
1785 – James Hutton saw the earth as a
self-regulating system. An abstract of
Hutton's Theory was first read at meetings
of the Royal Society of Edinburgh on 7
March 1785 and 4 April 1785. It was then
published in Volume I of the Transactions of the Royal
Society of Edinburgh, 1788.
1899 Swiss geologists Eduard Seuss introduces term
Biosphere (Ger. Biosphäre)
1926 - Biosphere - Vladimir Ivanovich
Vernadsky (1863-1945) develops the
concept: The biosphere is a stable, complex, adaptive, evolving life system
with the potential of operating in the right conditions as the major
geological force transforming a planet's crust and as the source of sufficient
free energy to power the start-up of a technosphere
Noosphere - Literally defined as "Sphere of Intelligence." Vernadsky
defined "a new state of the biosphere termed noosphere in which mankind
as a whole would become a new and a powerful geological entity able to
transform the planet." The outcome is has not been as optimistic as
Varnadsky’s idealistic prescriptions.
1934 – Redfield’s first paper addressing on the control of N and P in the oceans
1945 - Vernadsky’s article in American Scientist vol. 33; pp. 1-12 : The Biosphere
and the Noosphere
1946 - George Bush born in New Haven, Connecticut
1958 – Redfield’s paper on the homeostatic control of N and P and the link to oxygen
in the oceans
1972 – Gaia: the word invented by Lovelock, following a suggestion by William
Golding, his neighbour and author of Lord of the Flies. Gaia Theory - a theory
originated by James Hutton but popularised by Lovelock - views the Earth as a
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physiological system that is, in a sense, alive, at least to the extent that the climate and
chemical composition of the surface are self-regulated at a state favourable for life.
1974 - Formal statement of the Gaia Hypothesis and the control of the Atmosphere by
Lovelock and Margulis
1983 - Daisyworld published by Watson and Lovelock
1998 - Vernadsky’s “Biosphere” translated into English
B) INTERACTIONS BETWEEN THE
BIOSPHERE/LITHOSPHERE/NOOSPHERE
Lithosphere
C
l i m a t e Biosphere
Noosphere or
Technosphere
C
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C) WARMING PLANET PUZZLE
Theperature (C)
Temperature timecourses due to a warning Sun
40
40
20
20
0
0
-20
-20
-40
-40
-60
-60
-4
-3
-2
-1
Warming sun greenhouse effect - end
15C
Warming sun greenhouse effect -start
0C
Life temperature
Warming sun - no
greenhouse effect
0
9
Time (10 years)
30
300
20
200
Warming sun - greenhouse
effect -start 0C
Life temperature
10
Carbon dioxide
100
0
0
-4
-3
-2
-1
0
Relative quantity
30
300
UV
20
200
Carbon dioxide
Oxygen
10
100
0
0
-4
-3
-2
Time (109 years)
-1
0
Ozone
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D) MECHANISMS FOR CO2 DRAWDOWN
1) Weathering
e.g. CaAl2Si2O8+ CO2 +3H2O = Ca2+ + 2HCO3- + Al2Si2O5(OH)4
2) Photosynthesis
CO2 + H2O = CH2O + O2
Both probably occur but the chemical reaction is far slower than the biological.
Chemical weathering essentially transfers CO2 from the atmosphere to the oceans.
The biological reaction puts O2 into the atmosphere which will generate ozone, which
will cut down the UV reaching the surface. The combined effect of the
photosynthetic reaction will be a cooling of the surface of the planet and a reduction
in UV – both contributing to the improvement of the terrestrial system for
colonisation. The deposition of organic C in the sediments give rise to oil (and later
coal) deposits – which gave the basis for the industrial revolution in the mid-1700s
CO2
CO2 + H2O
O2 + [CH2O]
Microbial foodweb
O2
CO2 + H2O
O2 + [CH2O]
Microbial & metazoan
foodweb
[CH2O]
Oil &
Coal
However, the biological system only works if there is accumulation of organic
material – that is large faecal and similar particles are produced – i.e. the evolution of
the metazoa.
E) GAIA HYPOTHESIS (Lovelock J. E. and Margulis, L. 1974 Atmospheric
homeotatsis by and for the biosphere: the Gaia hypothesis. Tellus 26 1-9)
In “GAIA, A New Look at Life on Earth”, published in 1979, Lovelock defines the
Gaia Hypothesis: “This postulates that the physical and chemical condition of the
surface of the Earth, of the atmosphere, and of the oceans has been and is actively
made fit and comfortable by the presence of life itself. This is in contrast to the
conventional wisdom which held that life adapted to the planetary conditions as it and
they evolved their separate ways
For some reason Redfield’s then existing work was not taken as an example of Gaia
and the first example of a Gaian mechanism was the so called CLAW DMS
hypothesis for cloud formation put forward by Charlston et al in 1987 (Nature 1987
326 655-661)
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E) DAISYWORLD (Watson, A. J and Lovelock, J E. 1983, Biological homeostasis
of the global environment: the parable of Daisyworld. Tellus 35B 284-289)
This came out of a need to put some substance to the Gaia hypothesis.
The model considers the temperature on flat planet heated by a warming sun. The
surface of the planet is grey and it’s albedo is 0.5, i.e. it reflects 50% of incident
radiation. The heating of the planet is followed over in increase in solar luminosity
form 0.6 to 1.8, which results in a temperature rise from -5 to 70ºC
The growth of all three types of daisies have a identical temperature response, that
cardinal points are growth begins at 5ºC, ceases at 40ºC, the optimum growth
temperature (22.5ºC) is placed symmetrically between the two, see figure
Grey daisies
Black daisies
White daisies
The Temperature Consequence of the Varying Albedos of the Daisies
It is populated with black and/or white daisies which have albedos of 0.25 and 0.75
respectively. The former, as they absorb more heat, warm the local environment, the
latter cool it, relative to the non-occupied areas. The planet has also been populated
by grey daisies which have the same albebo and the planet’s surface and although
they grow they do not have any effect on the albedo of the course of the temperature
rise
The growth of the daisies themselves is affected by temperature (see below)and this
provides feeback
Temperature/growth Response of the Daisies
Optimum temperature = 22.5C
Relative growth rate
1
0.75
0.5
0.25
0
0
10
20
30
Temperature
40
50
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% Planet Covered
Barren Planet or Planet Populated by Grey Daisies
40
20
0
0.6
0.8
1
1.2
1.4
1.6
1.4
1.6
1.4
1.6
1.4
1.6
Solar Luminosity
Local Temperature
70
50
30
10
-10 0.6
0.8
1
1.2
Solar Luminosity
% Planet Covered
Planet populated by Black Daisies
40
20
0
0.6
+ve feedback
1
1.2
Solar Luminosity
70
Local Temperature
-ve feedback
0.8
50
30
10
-10 0.6
0.8
1
1.2
Solar Luminosity
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% Planet Covered
White Daisies
40
20
0
0.6
0.8
1
1.2
1.4
1.6
1.4
1.6
Solar Luminosity
Population collapses
-ve feedback
Local Temperature
70
50
30
10
-10 0.6
0.8
1
1.2
Solar Luminosity
% Planet Covered
Mixed Black & White Daisies
40
20
0
0.6
0.8
1
1.2
1.4
1.6
1.4
1.6
Solar Luminosity
Population collapses
-ve feedback
+v feedback
Local Temperature
70
50
30
10
-10 0.6
0.8
1
1.2
Solar Luminosity
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70
Local Temperature
Local Temperature
60
40
20
0
0.6
0.8
1
1.2
1.4
1.6
50
30
10
-10 0.6
0.8
Solar Luminosity
Local Temperature
Local Temperature
1.6
70
70
50
30
10
-10 0.6
1
1.2
1.4
Solar Lum inosity
0.8
1
1.2
Solar Luminosity
1.4
1.6
50
30
10
-10 0.6
0.8
1
1.2
Solar Luminosity
1.4
1.6
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Evolutionary & Gaia Lenton T. M. (1998) Gaia and natural selection. Nature 394
439-447
Lovelock proposed that Gaia behaved as a single organism and had evolved to control
the planetary environment to its “comfort”. This was a complete anathema to the
Darwinists (particularly the Oxford evolutionist Richard Dawkins, so-called
“Darwin’s rottweiler”), whose bedrock philosophy lies in evolution by competition, in
their view without competition there can be no evolution. Evolution cannot occur if
there is only one organism. This started off a long, and in the Darwinists’ view,
uncompleted debate.