The chart shows factors that influence climate change, glaciation and hemispheric reversals.
Earth's elliptical orbit around the Sun and the degree of tilt of Earth's axis in its path around the Sun, are factors that must be considered when discussing climate change. In the cycle of Earth’s Great Year the line off the North Pole axis (extending toward Polaris) scribes a complete circle in the heavens about every 25,800 years. A complete cycle takes between 25,000 and 28,000 years, depending on the amount of Earth's wobble. One cycle is “Earth’s Great Year” (also called a "Platonic Year.") Climate and atmospheric changes appear to become more acute toward the end and beginning of a new year.
This is evident when considering the sea and air temperatures of the last decade.
Solar radiation is another factor in climate change and ice melt. Summer solar radiation varies in the two hemispheres due to cycles in the Earth's tilt and the elliptical orbit. The factors affecting the relationship between changes in the Earth's tilt and orbit and climate changes are very complex and not fully understood.
Alarmists and those profiting from the global warming “crisis” stress the melting of the Artic glacial ice but conveniently fail to point out that the snow caps on South America highest mountains and the glacial mass in Antarctic are growing. Here is the latest science report:
An International Polar Year aerogeophysical investigation of the high interior of East Antarctica reveals widespread freeze-on that drives significant mass redistribution at the bottom of the ice sheet. While surface accumulation of snow remains the primary mechanism for ice sheet growth, beneath Dome A 24% of the base by area is frozen-on ice. In some places, up to half the ice thickness has been added from below. These ice packages result from conductive cooling of water ponded near the Gamburtsev Subglacial Mountain ridges and supercooling of water forced up steep valley walls. Persistent freeze-on thickens the ice column, alters basal ice rheology and fabric and upwarps the overlying ice sheet, including the oldest atmospheric climate archive, and drives flow behavior not captured in present models. (Source: Science Magazine)
The rise and fall of ice ages is caused by changes in the Earth's orbit around the Sun due to the influence of the other planets. These changes are slight and can be triggered by events like the earthquake and tsunami recently experienced in Japan.
The earliest ice ages came about every 41,000. Later ones came every 100,000 years. Scientists do not know what caused the change from 40,000 to 100,000 years, but they have noticed that the 100,000 year cycle aligns with periods of Earth’s more-elliptical orbits. Earth's orbit around the sun changes shape every 100,000 years, becoming either more round or more elliptical. The shape of the orbit is known as its "eccentricity." The 41,000-year cycle of the tilt of Earth’s axis is related. The original research correlating climate, glaciation and orbit and was done by University of California (Santa Barbara) geologist Lorraine Lisiecki.
Lisiecki believes that climate change involves complicated interactions between different parts of the climate system and three orbital systems: 1) eccentricity of Earth’s orbit; 2) tilt of Earth’s axis; and 3) precession or change in the orientation of the rotation axis.
It appears that ancient astronomers were aware of axial precession. This is evident from the study of monuments in southern Africa and in Egypt. In his book The Great Pyramid Decoded, E. Raymond Capt says, “the most precise alignment of the Dragon Star and the Great Pyramid occurred on the Vernal Equinox of the year 2141 B.C.”
An imaginary line extending from the Earth’s North Pole axis into the heavens points to Polaris. In the cycle of Earth’s Great Year (also called the Platonic year) the line off the North Pole scribes a complete circle in the heavens over about 25,800 years.
They were also aware of lunisolar precession. Many of the ancient observatories, including Stonehenge, accurately record the 18.6-year cycle of the moon. In this cycle, every solar eclipse repeats itself at a different place on the earth every 18.6 years. It also creates an 18.6-year wave in the precession called “nutation.”
The term “general precession” applies to two gravitational factors: planetary precession and lunisolar precession. Planetary precession is due to the small angle between the gravitational force of the other planets on Earth and its orbital plane (the ecliptic), causing the plane of the ecliptic to shift slightly relative to inertial space. Lunisolar precession is about 500 times larger than planetary precession. Other planets also cause a slight movement of Earth's axis in inertial space.
Precession has an effect on hydrological cycles in the hemispheres. These cycles appear to reverse at times. Evapotranspiration, the movement of water from the land to the atmosphere, increased to about 1 inch/6.2 millimeters per year from 1982 to 1998. However, when the Earth completed its axial precession in the summer of 1998, evapotranspiration slowed dramatically and stopped in some parts of the world. Areas that began to dry include southeast Africa, much of Australia, central India, large areas of South America, and parts of Indonesia. At the same time, parts of Pakistan and Australia, and areas of the Sahal such as central Niger, experienced flooding from excessive seasonal rains. The same is true for parts of North America.
Related reading: The Bi-polar Seesaw; South American Glaciers Growing; Genesis and Climate Change; Climate Cycles and Noah's Flood; Two Environmentalists Knock Heads; Lower Solar Irradiance, Higher Atmospheric Temps?