COPENHAGEN – When it comes to global warming, extreme scare stories abound. Al Gore, for example, famously claimed that a whopping six meters (20 feet) of sea-level rise would flood major cities around the world.
Gore’s scientific advisor, Jim Hansen from NASA, has even topped his protégé. Hansen suggests that there will eventually be sea-level rises of 24 meters (80 feet), with a six-meter rise happening just this century. Little wonder that fellow environmentalist Bill McKibben states that “we are engaging in a reckless drive-by drowning of much of the rest of the planet and much of the rest of creation.”
Given all the warnings, here is a slightly inconvenient truth: over the past two years, the global sea level hasn’t increased. It has slightly decreased . Since 1992, satellites orbiting the planet have measured the global sea level every 10 days with an amazing degree of accuracy – 3-4 millimeters (0.2 inches). For two years, sea levels have declined. (All of the data are available at sealevel.colorado.edu.)
This doesn’t mean that global warming is not true. As we emit more CO2, over time the temperature will moderately increase, causing the sea to warm and expand somewhat. Thus, the sea-level rise is expected to pick up again. This is what the United Nations climate panel is telling us; the best models indicate a sea-level rise over this century of 18 to 59 centimeters (7-24 inches), with the typical estimate at 30 centimeters (one foot). This is not terrifying or even particularly scary – 30 centimeters is how much the sea rose over the last 150 years.