"The recent cold wave hitting the northern hemisphere has led some to ask, “What ever happened to global warming?” Al Gore might have been trying to convince you that scientists believe the Earth is heating up, but it appears that mother nature doesn’t agree. Even though the extremely cold weather does not really demonstrate anything about long-term climate change, real science shows that we may, in fact, be on the verge of a new, global ice age.
"To the best of scientific knowledge, climate change is driven by changes in the orbital relationship of the Earth to the Sun, which affect the amount of solar radiation reaching the high northern regions. There are three major cycles that could affect the Earth’s climate.
"First, the wobble of the spinning Earth, called the precession of the equinox, is combined with the rotation of the orbit as a whole, to create a cycle where, every 21,000 years, the north pole of the Earth points in such a way that Summer in the northern hemisphere is happening when the Earth is farthest in its orbit from the Sun. This is the situation today. Second, the angle of inclination of the Earth’s axis, or obliquity varies over 40,000 years from about 22 to 25 degrees. And, third, the elliptical orbit itself changes shape, getting more or less circular, over a period of between 100 and 400 thousand years.
"The first suggestion that climate was driven by astrophysical sources, was proposed in 1830 by English astronomer John Herschel. Later, American scientist Louis Agassiz suggested that the yearly advance and retreat of Alpine glaciers might have a much longer cycle, and could periodically form continental ice sheets, causing hitherto unexplained geological formations. Today, we call these periods of widespread glaciation ice ages.
"The modern version of the astronomical theory was due to Vladimir Koeppen. He and his son-in-law, Alfred Wegener studied how the amount of solar radiation hitting the Earth could change as the superposition of the three major orbital cycles - precession, obliquity, and ellipticity - reinforced or canceled one another. In 1920, Koeppen collaborated with Serbian mathematician Milutin Milankovitch to make precise mathematical calculations of the combined effect of the three cycles. Today, his results suggest a 10,000 year cycle of glaciation.
"A northern hemisphere glaciation might begin if the Earth is in such a configuration, where the ellipticity of the orbit is at its maximum, while its axis pointed toward the sun at its farthest orbital position. Glaciers typically grow and advance during the winter months, destroying everything in their path, depressing the ground under their enormous weight. During the Summer, they naturally melt and recede, or calve pieces into the oceans.
"However, if the Summer is not warm enough, because of the configuration of the Earth in its orbit, the glaciers won’t recede back to their earlier position, but will begin advancing, year upon year. More and more of the Earth’s water will become locked into them, lowering the levels of the oceans, as their bulk engulfs more and more of the Northern hemisphere. Eventually, they would again reach as far down as Chicago, pushing the wreckage of Montreal and Copenhagen down to lower latitudes. When they finally melt thousands of years later, they would cause massive, canyon-forming floods, wiping out the civilization that might be left on the ice age coasts.
"So, if you’re in a panic, trying to reduce your carbon emissions, breathe easy. We are living in a dynamic universe. Climate change is a much more complicated process than you once imagined."