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The Ends of the Earth
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Two books. Earth as a rare body in space and Earth "as we presently know it" as a special place in time. Earth was different in the past and it will be quite different in the future.
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Mars, Earth and Venus, very different neighbors.
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Mars is so cold that carbon dioxide (dry ice) freezes on the winter pole and Venus is so hot that tin and lead would melt on its surface.
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Out of a total lifetime of 12 billion years, the age of plants and animals will last only about a billion years.
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Earth on the cosmic junk heap
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The oceans may be lost "soon" by the moist greenhouse or "later" by a runaway greenhouse warming. If they are lost soon, life may survive on Earth for another 5 billion years or more.
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The ultraviolet glow of hydrogen escaping from the Earth- the ocean is very slowly being lost to space. This picture was taken from the surface of the Moon by the crew of Apollo 16. Sunlight comes from the lower right. |
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The atmosphere viewed from a high altitude balloon. The edge between bright haze and the darker blue is the top of the troposphere at 12 km and the beginning of the stratosphere. Water vapor is transported upwards through the rapidly cooling troposphere, through the cold but constant temperature stratosphere and eventually to the top of the atmosphere where it is split to oxygen that stays and hydrogen that is lost to space.
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The greenhouse effect. Sunlight gets in but part of the outgoing infrared is blocked. (note: This is apparently not the main reason why real greenhouses stay warm.)
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Possible future temperature history of Earth. If the oceans are not lost, Earth will begin a thermal runaway leading to very high surface temperataures. Note the the surface of the moon, with no greenhouse warming, only slightly becomes hotter over times of a few billion years. Greenhouse processes greatly amplify the effects of solar warming. The "dead line" is a generous estimate of the leathal themperature of any reasonable terrestrial organism.
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The sun has been good but soon it constant increase in brightness will cause problems.
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Ocean- the source of life becomes a geuine liability in the light of the aging Sun.
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Gradual brightening of the sun as hydrogen in the sun's core is slowly converted into helium.
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The decline of carbon dioxide over geologic time. (Berner)
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Bad water Death Valley - what the oceans will look like some day.
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Bad water Death Valley
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Salt making ponds in San Francisco bay a proxy for Earth when its oceans nearly gone- lost to space. As the oceans dry, the formerly blue planet Earth will turn pink due to the build up of salt, the rusting of surface iron and the growth of halophyllic (salt loving) bacteria similar to those cauring the red color in the salt ponds.
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The tree of life
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Pruning the tree of life with ever increaseing temperatures. The loss of specific species is shown only for illustration and is not meant to imply the most probable sequence of species extinction.
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The pruned tree with only the highest temperature survivors remaining.
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In a little over 12 billion years after its formation, the Sun will explode, lose nearly half of its mass and form a spectacular "planetary nebula" (an historical misnomer that has nothing to do with planets). Planetary nebula image from Hubble Space Telescope.
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The Ends of the Earth
|
|
Two books. Earth as a rare body in space and Earth "as we presently know it" as a special place in time. Earth was different in the past and it will be quite different in the future.
|
|
Mars, Earth and Venus, very different neighbors.
|
|
Mars is so cold that carbon dioxide (dry ice) freezes on the winter pole and Venus is so hot that tin and lead would melt on its surface.
|
|
Out of a total lifetime of 12 billion years, the age of plants and animals will last only about a billion years.
|
|
Earth on the cosmic junk heap
|
|
The oceans may be lost "soon" by the moist greenhouse or "later" by a runaway greenhouse warming. If they are lost soon, life may survive on Earth for another 5 billion years or more.
|
|
The ultraviolet glow of hydrogen escaping from the Earth- the ocean is very slowly being lost to space. This picture was taken from the surface of the Moon by the crew of Apollo 16. Sunlight comes from the lower right. |
|
The atmosphere viewed from a high altitude balloon. The edge between bright haze and the darker blue is the top of the troposphere at 12 km and the beginning of the stratosphere. Water vapor is transported upwards through the rapidly cooling troposphere, through the cold but constant temperature stratosphere and eventually to the top of the atmosphere where it is split to oxygen that stays and hydrogen that is lost to space.
|
|
The greenhouse effect. Sunlight gets in but part of the outgoing infrared is blocked. (note: This is apparently not the main reason why real greenhouses stay warm.)
|
|
Possible future temperature history of Earth. If the oceans are not lost, Earth will begin a thermal runaway leading to very high surface temperataures. Note the the surface of the moon, with no greenhouse warming, only slightly becomes hotter over times of a few billion years. Greenhouse processes greatly amplify the effects of solar warming. The "dead line" is a generous estimate of the leathal themperature of any reasonable terrestrial organism.
|
|
The sun has been good but soon it constant increase in brightness will cause problems.
|
|
Ocean- the source of life becomes a geuine liability in the light of the aging Sun.
|
|
Gradual brightening of the sun as hydrogen in the sun's core is slowly converted into helium.
|
|
The decline of carbon dioxide over geologic time. (Berner)
|
|
Bad water Death Valley - what the oceans will look like some day.
|
|
Bad water Death Valley
|
|
Salt making ponds in San Francisco bay a proxy for Earth when its oceans nearly gone- lost to space. As the oceans dry, the formerly blue planet Earth will turn pink due to the build up of salt, the rusting of surface iron and the growth of halophyllic (salt loving) bacteria similar to those cauring the red color in the salt ponds.
|
|
The tree of life
|
|
Pruning the tree of life with ever increaseing temperatures. The loss of specific species is shown only for illustration and is not meant to imply the most probable sequence of species extinction.
|
|
The pruned tree with only the highest temperature survivors remaining.
|
|
In a little over 12 billion years after its formation, the Sun will explode, lose nearly half of its mass and form a spectacular "planetary nebula" (an historical misnomer that has nothing to do with planets). Planetary nebula image from Hubble Space Telescope.
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