Results 231 to 240 of about 519,289 (290)

Evolution of the atmosphere

Proceedings of the Geologists' Association, 1998
Planetary atmospheres depend fundamentally upon their geochemical inventory, temperature and the ability of their gravitational field to retain gases. In the case of Earth and other inner planets, early outgassing released mainly carbon dioxide and water vapour. The secondary veneer of comets and meteorites added further volatiles.
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Venus: Atmospheric Evolution

2013
This chapter discusses the greenhouse effect and climate evolution using Venus as an example. Venus mostly has an Earth-like inventory of volatile gases—the basic ingredients of atmospheres and oceans—but with one glaring exception: water. Earth's ocean is 300 times as massive as its atmosphere.
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Atmospheric chemistry: the evolution of our atmosphere

Journal of Photochemistry and Photobiology A: Chemistry, 1992
Abstract Earth's atmosphere is a disequilibrium mixture of oxidizable materials in the presence of large amounts of oxygen. The entropy reduction is brought about by living organisms using photochemical energy from the Sun. Almost all the oxygen in the atmosphere is derived from photosynthesis; inorganic photochemistry can produce only 10 −9 of the ...
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Evolution of the atmosphere and oceans

Nature, 1986
The residence times of most constituents of the atmosphere and oceans are small fractions of the age of the Earth and, in general, their rate of output has been nearly equal to their rate of input. We are disturbing a number of these dynamic equilibria quite severely. The mineralogy of marine evaporites rules out drastic changes in the composition of
H D, Holland, B, Lazar, M, McCaffrey
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EVOLUTION OF EARTH'S ATMOSPHERE

2003
Although the planets Mercury, Venus, Earth, and Mars have masses within a single order of magnitude range, they possess atmospheres with extremely different properties (Table 1). These bodies may have initially possessed primordial atmospheres of solar composition whose dominant light gases (hydrogen and helium) were lost to space and replaced by ...
E.J. Gaidos, Y.L. Yung
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Evolution, atmospheric oxygen, and complex disease

Physiological Genomics, 2007
If evolution is an accurate statement of our biology, then disease must be tightly associated with its patterns. We considered selection for more optimal capacity for energy transfer as the most general pattern of evolution. From this, we propose that the etiology of complex disease is linked tightly to the evolutionary transition to cellular ...
Lauren Gerard, Koch, Steven L, Britton
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EVOLUTION OF ATMOSPHERIC OXYGEN

2003
Abundant free oxygen in the atmosphere distinguishes our planet from all others in the solar system. Earth’s oxygen-rich atmosphere is a direct result of life. The current atmosphere contains (by volume) 78.09% N2, 20.95% O2, 0.93% Ar, 0.036% CO2, and additional trace gases.
Catling, DC, Zahnle, K
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Evolution of Earth’s Atmosphere

2012
Earth’s atmosphere has a central role in keeping the environmental conditions on Earth suitable for life. When considering the evolution of the composition of the atmosphere, attention should be paid specifically to greenhouse gases and oxygen. The most important greenhouse gases are water vapor, carbon dioxide and methane.
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The evolution of the prebiotic atmosphere

Origins of Life, 1984
One-dimensional radiative convective and photochemical models are used to estimate the vertical temperature structure and composition of the earth's prebiotic atmosphere. Greatly enhanced CO2 levels (100-1000 times present) are required to keep the mean surface temperature above freezing in the face of decreased solar luminosity during the earth's ...
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Formation and Evolution of Titan’s Atmosphere

Space Science Reviews, 2005
The origin and evolution of Titan’s enigmatic atmosphere is reviewed. Starting with the present-day volatile inventory, the question of what was the original composition on Titan and how a satellite of similar size to other Galilean moons managed to acquire and hold on to the required material is discussed.
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