by William Logan

Created on: October 06, 2009   Last Updated: October 07, 2009

A recent poll by the Pew Research Center found that 96.4 per cent of all climate scientists and 82 per cent of all scientists believe that anthropogenic carbon dioxide is causing global warming. For all practical purposes, every bit of new research data indicates that this is true, and that is happening faster and more dramatically than has been expected, even as recently as the 2007 IPCC report. Remarkably, 54 per cent of all Americans still believe that the issue is undecided, even among scientists.

In the most basic of terms, energy from the sun arrives as short wavelength radiation. It is absorbed by the Earth and reradiated as longer wavelength, ultraviolet radiation. In the process, greenhouse gasses (water vapor, carbon dioxide, methane, and others) absorb some of the escaping radiation and trap it in the atmosphere, causing the atmosphere to heat up, much like the glass walls of a greenhouse.

This phenomenon was originally described in scientific literature over 100 years ago and has been confirmed countless times. It is accepted scientific principle and not the subject of debate. Without the greenhouse effect, the planet would be some 70 degrees colder. By comparison, a 7 degree drop in aggregate temperatures caused the ice age.

Venus, the planet closest to Earth, has an atmosphere that is almost exclusively made up of greenhouse gasses, and atmospheric temperatures exceed 900 degrees as a result.

The Earths ecosphere has evolved over the millennia to accommodate an atmospheric concentration of carbon dioxide of about 180 ppm. Unfortunately, levels have risen sharply since the burning of fossil fuels began, reaching about 380 ppm, about 27% higher than any time in the last 650,000.

The particular carbon isotopes present are consistent with the burning of fossil fuels and not consistent with volcanic activity or oceanic outgassing. We are essentially wrapping a heat emitting body in an extra layer of insulation and appearing puzzled that it heats up.

Measurements of aggregate temperatures consistently show a steadily warming planet. Temperatures fluctuate over short time spans due to a variety of factors like dispersed aerosols from pollution or volcanoes, decadal oceanic shifts, and La Nina or El Nino events.

Despite these short term anomalies, the temperature trends are very steadily upward and reports that the warming has stopped or reversed are simply inaccurate. The recent increase in the rate of warming has led to the "hockey stick" description

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