Greenhouse Gas Is Ramping Up Fast

Larry O'Hanlon, Discovery News


Nov. 30, 2006 — The latest real-world measurements of carbon dioxide levels in Earth's atmosphere show that it's increasing at breakneck speed, despite some preliminary efforts in some parts of the world to rein in fossil fuel burning — the main source of the surplus greenhouse gas.

The new data reported in Tasmania last week shows there were 7.9 billion tons of carbon emitted in 2005 and that the 1 percent per year carbon dioxide concentration increase rate of the 1990s has already jumped to 2.5 percent per year. These numbers all point to a worst-case scenario greenhouse effect and global warming.

"There is an agreement between emissions and concentrations," said atmospheric researcher Mike Raupach of Australia's Commonwealth Scientific and Industrial Research Organization (CSIRO).

The data, as well as other data on rising global temperatures and sea level rise, are reaching the point where they can be used to check the models.

"People are now able to do comparisons between the way aspects of climate change are playing out and how the models predicted," said Raupach.

The documented rise in carbon levels was revealed as the U.S. Supreme Court considers whether or not the Environmental Protection Agency should regulate carbon dioxide emissions. Currently, carbon dioxide and other heat-trapping pollutants have not been classified as pollutants by the federal agency.

The new data could add some urgency to the Supreme Court's arguments.

Six climate scenarios were modeled in the late 1990s for the Intergovernmental Panel on Climate Change's 2000 report. The IPCC scenarios range from a world that vigorously curtails its fossil fuel addiction, to one in which greenhouse gas emissions continue to grow unchecked.

"The emissions are tracking the two uppermost of those scenarios," said Raupach. "That’s not good."

Like carbon dioxide, sea level rise had been projected in 1995 to climb between 0.04 to 0.12 inches (1 and 3 millimeters) per year because of global warming melting mountain glaciers, high-latitude ice and the thermal expansion of water in warmer oceans.

Now it appears that sea level is rising at 3 millimeters (0.12 inches) per year – again, a scenario on the wrong end of where we’d like to be, Raupach said.

Greenhouse gas researchers in the United States have come to the same conclusions.

"Carbon dioxide is now rising 2 parts per million per year," said Pieter Tans, senior scientist and head of greenhouse gas monitoring at the U.S. National Oceanic and Atmospheric Administration’s Earth System Research Laboratory in Colorado. "In the 1980s it was 1.4 parts per million and in the 1950 and 60s it was 0.7 parts per million per year."

Tans' team uses air data from the almost five-decade old Mauna Loa station in Hawaii, which has proven to be an accurate representation of concentrations worldwide.

"Then you look at total (carbon dioxide) emissions," Tans told Discovery News. "Two billion tons of carbon per year in the 1950 and 60s and now it’s above seven billion tons."

The non-stop growth in carbon emissions from fossil fuel burning, plus the fact that it takes centuries to get the carbon out of the atmosphere, make it imperative that we act immediately to lower greenhouse gas emissions, Tans argued.

"What we are doing (with fossil fuel burning) has a cumulative effect," said Tans.