November 13, 2010

Gaia

To the ancient Greeks, Gaia, offspring of Chaos, was

the broad-chested personification of Mother Earth.

Gaia is 4.5 billion years old, and, to our knowledge, is the

only astral body in our universe capable of sustaining life.

Uni-cellular micro-organisms first appeared 3.4 billion years ago,

multi-cellular organisms much later, 700 million years ago.

Mammals appeared 65 million years ago, and 1.5 million years

ago, Homo erectus achieved the ability to light and control fire.

Homo sapiens appeared 175,000 years ago, and by 10,000 years

ago, was replacing forests with agricultural monocultures.

. . .

The sun, 4.6 billion years old, warms at it ages, and since life

began, has increased its energy output to Gaia by 25 percent.

It seems, therefore, that in order to have continued being

hospitable to life, Gaia must have controlled her climate.

Indeed, science has now shown definitely that Gaia’s

ecosystem as a whole (the Earth System), regulates its climate.

As living organisms, surface rocks, ocean and atmosphere

co-evolve, they are affected by, and in turn, affect the climate.

This interaction with climate has a specific direction – the

maintenance of conditions optimum for life as it then exists.

Within a wide range of intensity in solar radiation, natural

selection favors those organisms which steady Gaia’s climate.

Imagine Daisyworld.

Daisyworld is a flat planet with an ecosystem which consists of

two daisy species, one black and the other white, both evolving

by natural selection in Darwinian fashion. The planet is

illuminated by a sun, and its surface temperature is determined

by how much of the radiant heat from the sun is absorbed,

and how much of it is reflected back into space. The amount

of heat absorbed or reflected is proportional to the area

covered by the black and the white daisies, respectively.

Both types of daisies start growing at 41 degrees Fahrenheit,

grow best at 72.5 degrees, and stop growing above 104 degrees.

This model system regulates its own temperature. Starting

from a cold planet, increasing solar radiation produces first the

growth of black daisies, their darkness enabling them to absorb

more heat than their white competitors. They spread, thereby

increasing the planet’s temperature toward daisies’ optimum

level. Further increasing solar radiation kills black daisies and

favors white ones, their light color enabling them to reflect

heat, thereby lowering the planet’s temperature toward

daisies’ optimum level. Further increasing solar radiation kills

all daisies. The planet, as a self-regulating organism, dies.

. . .

Maintaining a steady concentration of carbon dioxide in the

atmosphere, is a major way by which Gaia regulates her climate.

Humans have been raising this concentration since they started using fire

and felling forests. The transgressions were small and Gaia compensated.

In the past 200 years, however, the amount and rate of human-

induced emissions have far exceeded Gaia’s ability to compensate.

Since the Industrial Revolution, human actions have caused the injection

into the atmosphere of 1,835 billion metric tons of carbon dioxide.

In just one year, 2008, anthropogenic CO₂ emissions were 36 billion tons,

a 27 percent increase over emissions in 1990 – just 18 years earlier.

Gaia has never tolerated species which de-stabilize her climate.

She herself will survive, albeit hotter, and with a diminished biosphere.

Natural selection is set to cull our species mercilessly.

References

Principal Reference:

Lovelock, James. 2009. The vanishing face of Gaia – a final warning. New York, N.Y.: Perseus/Basic Books.

P. 163 (The sun has warmed by at least 25 percent since life began 3.4 billion years ago); P. 164 (For about 2 or 3 billion years from its start, the biota – that is, all forms of life on Earth – were micro-organisms. Only in the last 500 to 900 million years have multi-cellular organisms played a part in the evolution of our planet); Pp. 171-173 (Daisyworld – the model of an emergent system in which climate and organisms are tightly coupled and evolve together); P. 179 (The goal of self-regulation is the maintenance of habitability); P. 180 (A look at the Earth’s climate history tells us that in hot states, Gaia can still self-regulate and survive with a diminished biosphere); P. 181 (Species that improve habitability flourish and those that foul the environment are set back or go extinct); P. 247 (The resilience of Gaia to perturbation would be reduced on a hot Earth, and a rebirth of twentieth-century civilization would then be a major perturbation);

Pp. 254-255 (The Gaia Hypothesis: Life on Earth actively keeps the surface conditions always favorable for whatever is the contemporary ensemble of organisms. The Gaia Theory: The Earth is a self-regulating system made up of the totality of organisms, the surface rocks, the ocean and the atmosphere tightly coupled as an evolving system. The goal of the system is the regulation of surface conditions so as always to be as favorable for contemporary life as possible).

Other References:

Allen, Myles, David Frame, Chris Huntingford, Chris Jones, Jason Lowe, Malte Meinshausen and Nicolai Meinshausen, 2009. “Warming caused by cumulative Carbon Emissions towards the trillionth Tonne.” Nature. Letter. Volume 458, April 30.

http://www.nature.com/nature/journal/v458/n7242/full/nature08019.html. Accessed November 14, 2010.

“Total anthropogenic emissions of one trillion tonnes of carbon (3.67 trillion tonnes of CO₂), about half of which has already been emitted since industrialization began, results in a most likely peak carbon dioxide-induced warming of 2 degrees Celsius above pre-industrial temperatures, with a 5-95 percent confidence interval of 1.3-3.9 degrees Celsius.”

I deduce, therefore, that since industrialization, a total of (1,000 / 2) x 3.67 = 1,835 billion tons of carbon dioxide have been emitted into the atmosphere from anthropogenic sources.

Hall, Francoise,

2005. “Ask the Mosquitoes.” (Poem). March 19 (13 pages, unpublished). (See Wilson 1992/1999).

Wikipedia, 2010,

“Age of the Earth.”

http://en.wikipedia.org/wiki. Updated November 11, 2010. Accessed November 13, 2010.

The age of the Earth is 4.54 billion years.

“Carbon dioxide in Earth’s Atmosphere.”

http://en.wikipedia.org/wiki. Updated October 28, 2010. Accessed November 13, 2010.

“In 2008, 8.67 Gigatons of carbon (31.8 Gigatons of CO₂), were released from fossil fuels worldwide, compared to 6.14 Gigatons in 1990. In addition, land use change contributed 1.20 Gigatons in 2008, compared to 1.64 Gigatons in 1990.”

Therefore, in 1990, anthropogenic emissions totaled

(6.14 + 1.64) x 3.67 = 28.56 billion tons (Gigatons) of CO₂, and,

in 2008, totaled

(8.67 + 1.20) x 3.67 = 36.23 billion tons (Gigatons).

The percentage increase is [(36.23 – 28.56) / 28.56] x 100 = 26.86 percent.

“Gaia (Mythology)”

http://en.wikipedia.org/wiki. Updated November 10, 2010. Accessed November 13, 2010.

“History of Agriculture.”

http://en.wikipedia.org/wiki. Updated November 14, 2010. Accessed November 14, 2010.

Agriculture was developed at least 10,000 years ago.

“Homo erectus.”

http://en.wikipedia.org/wiki. Updated November 9, 2010. Accessed November 14, 2010.

Homo erectus, a hominid species now extinct, lived from about 1.8 to 1.3 million years ago. The controlled use of fire dates back to 1.5 million years ago.

“The Sun.”

http://en.wikipedia.org/wiki. Updated November 12, 2010. Accessed November 14, 2010.

The Sun was formed about 4.57 billion years ago.

“Timeline of human Evolution.”

http://en.wikipedia.org/wiki. Updated November 14, 2010. Accessed November 14, 2010.

Homo sapiens appeared from 195,000 to 160,000 years ago.

Wilson, Edward. 1992/1999. The diversity of life. New York, N.Y.: W. W. Norton.

Summarized in Francoise Hall, 2005. “Ask the Mosquitoes.” (Poem). March 19 (13 pages, unpublished).

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