The smaller the tilt the smaller the temperature difference between winter and

The smaller the tilt the smaller the temperature

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The smaller the tilt, the smaller the temperature difference between winter and summer . A reduced seasonal contrast could promote the growth of ice sheets. Winters would be warmer, bringing more snowfall, because the capacity of the air to contain moisture increases with temperature. Summer temperatures would be cooler, meaning less snow would melt. The result would be the growth of ice sheets. This cycle is too slow to bring about the climate change we have observed since the Industrial Revolution began in 1850 AD.
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3) Precession (Earth wobbling on its axis) Precession refers to a change in where Earth’s axis points . The Earth wobbles slowly as it spins on its axis. Presently the axis points toward the North Pole (Polaris). About 14,000 AD the axis will point toward the bright star, Vega. About 28,000 AD Polaris will once again become the North Star. In about 12,000 years, when the axis is tilted toward Vega, the orbital positons at which the winter and summer solstices occur will be reversed. a) the Northern Hemisphere will experience winter at aphelion (when Earth is farthest from the Sun). b) the Northern Hemisphere will experience summer at perihelion (when Earth is closest to the Sun). The result: summers will be warmer in the Northern Hemisphere and winters colder.
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Precession changes the orientation of hemispheres and land masses to the Sun . Precession occurs over a cycle of 26,000 years. This is too long a period to cause the warmer temperatures we have observed since 1850 AD .
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Milankovitch Cycles Summary Studies have found that major variations in climate over the past several hundred thousand years were closely associated with changes in the geometry of Earth’s orbit . Cycles of climate change were shown to correspond closely with the periods of obliquity, precession, and orbital eccentricity . These studies strongly stated that changes in the Earth’s orbital geometry are the fundamental cause of the succession of Quaternary Ice Ages. These same studies also predicted a cooler climate and extensive glaciation in the Northern Hemisphere over the next 20,000 years, not taking into account human influenced changes.
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Solar Variability and Climate No major long-term variations in the total intensity of solar radiation have yet been measured outside the atmosphere . Scientific evidence has shown no significant correlation between solar activity and climate . Furthermore, no connection between solar variations and weather has yet been well established. Some propose explanations based on sunspot cycles: a) for sunspots and temperatures b) for sunspots and drought Neither have proved to be substantiated by scientific evidence. The sunspot cycle produces a 0.1% variation in solar energy reaching the Earth, and is counted out as a cause for present climate change. Solar variability is dismissed by scientists as a factor in climate change.
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Climate Change Encompasses: 1) global warming 2) changes in annual precipitation 3) increased weather variability 4) changes in ocean currents 5) biosphere impacts 6) geographic impacts
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Climate Change Summary (Global Temperatures)
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