Global warming is real, and this is a retelling of an “inconvenient truth.” Global warming refers to the increase in average temperature of Earth’s near-surface air and oceans during the 20th century and, more ominously, its projected continuation.
What has happened up to now is irrefutable. Measurements coupled with sophisticated analysis to glean trends from random daily and seasonal variations indicate that the global temperature increased 0.74 degree Celsius (1.3 Fahrenheit) between the start and end of the 20th century; the last decade was the warmest on record.
But is the trend continuing for the next 100 years? And, is it human-caused or part of the natural cycle that has existed since the Earth formed 4.5 billion years ago? Yes and yes.
Less than 1 degree temperature rise per century seems innocuous enough. But a couple of more degrees and ice in the Arctic and Antarctica melts, sea level rises, coastal cities disappear, and desertification spreads. Even if the looming catastrophe were not human- caused, the only species capable of slowing the trend should aggressively tackle the problem, whatever the sacrifice.
Scientists employ the laws of nature as they understand them; by solving resulting dynamical equations, the future can be predicted.
Predictions are made statistically; for example, if current trends continue, there is a 25 percent probability that warming over the next 25 years will exceed 2 degrees C. Certainty is replaced by likelihood.
Dismissing the science because of its inability to provide certainty but rather likelihood is playing Russian roulette with the health and prosperity of future generations.
The sudden change in the rate of global warming correlates strongly with the increased release into the atmosphere of human-caused carbon dioxide and, to a lesser extent, other greenhouse gases such as nitrous oxide and chlorofluorocarbons.
For the foreseeable future, man needs to conserve energy, seek alternatives to fossil fuel, control population growth, and provide sustainable balance to our delicate ecosystem.
Mohamed Gad-el-Hak is a professor of mechanical engineering at Virginia Commonwealth University. He wrote this for The Free Lance-Star in Fredericksburg, Va.
