Global Cooling?

Some say the world will end in fire,
Some say in ice.
--Robert Frost

The theory of stellar evolution predicts that in five billion years the sun will become a red giant.

Earth's biosphere will be destroyed as the Sun gets brighter while its hydrogen supply becomes depleted. The extra solar energy will cause the oceans to evaporate to space, causing Earth's atmosphere to become temporarily similar to that of Venus, before its atmosphere also gets driven off into space.

After it burns off the last of its hydrogen, the sun will implode to the size of a planet but keep most of its mass. The dense white dwarf will flicker for billions of years before it winks out in the blackness of space. The earth, if it has not already been incinerated by the red giant, is destined to be a frozen, atmosphere-less husk accompanying its former sun and sister planets on their final dark journey.

Whether or not mankind is the principal cause of the earth’s recent warming trend is a subject for debate, but surely everyone must agree that the effects of solar changes can and will ultimately dwarf any impact that homo sapiens has on earth’s condition.

Some scientists theorize that variations in the earth’s orbit are the primary cause of earth’s cycles of glacier expansion and contraction. They believe that the imminent danger is that of a new ice age, not rising temperatures.

[G]lobal warming always precedes an ice age. That makes the current period of global warming a mere blip that constitutes additional indication of the ice age to come.

"I feel we're on pretty solid ground in interpreting orbit around the sun as the primary driving force behind ice-age glaciation. The relationship is just too clear and consistent to allow reasonable doubt," Dr. Kukla said. "It's either that, or climate drives orbit, and that just doesn't make sense."

I don’t know what or whom to believe, but while our state of knowledge is in flux it’s grating and presumptuous for one side to declare that its point of view is settled science.

I get my religion straight on Sundays, but at least I know when I'm worshipping. © 2007 Stephen Yuen