Are Recent Cyclones More Evidence Of Global Warming?

Dear EarthTalk: Are the recent cyclones and droughts in Australia and elsewhere more evidence of global warming?

—Billy Howard Los Angeles, CA

Scientists can’t blame individual storms or droughts on climate change, but many believe that human-induced global warming is increasing the severity and frequency of such weather “anomalies.” Indeed, on February 2, 2007 scientists with the Intergovernmental Panel on Climate Change (IPCC) released a long-awaited 21-page report confirming “with 90 percent certainty” that increases in man-made greenhouse gases since the mid-20th century are raising the planet’s temperature and destabilizing the climate.

Besides hurricanes like Katrina that have affected the northern hemisphere, a number of high-impact tropical cyclones and typhoons have occurred around the world in just the last few years, with Australia’s mammoth Cyclone Larry topping the list in terms of intensity. That March 2006 storm battered the northern Queensland coast with 180 mile-per-hour winds, causing hundreds of millions of dollars in property damage and virtually wiping out Australia’s banana crop. Thanks to Australia’s top-notch weather forecasting and emergency preparedness, however, unlike Katrina, Larry claimed no human lives.

Meanwhile, higher global temperatures have at least worsened if not outright caused drought conditions around the world, and Australia has been no exception. A 2003 report by the Australia chapter of the World Wildlife Fund found global warming to be a key factor in the severity of the country’s 2002 drought, one of four especially harsh droughts in just the last 50 years. The 2002 drought, which many scientists consider to be still in effect, was particularly memorable as Australians endured higher daytime temperatures than had ever been recorded during any March-November winter season. Besides causing countless bush fires in the Australian Outback, the drought has led to a significant drop in agricultural production, causing hundreds of millions of dollars in economic losses, according to government data.

An original 1997 signatory to the landmark Kyoto Protocol calling for reduced greenhouse gas emissions, Australia’s government nevertheless has refused to ratify and adhere to the terms of the treaty. Prime Minister John Howard has taken a position similar to that of U.S. President George W. Bush, who considers the terms of Kyoto bad for industry.

But just because Australia hasn’t ratified Kyoto doesn’t mean it has refused to acknowledge the potential environmental impacts of global warming. The country has pledged $300 million over three years to implement various strategies to reduce greenhouse gas emissions. It has also signed onto the Asia-Pacific Partnership on Clean Development and Climate, an agreement with India, Japan, China, South Korea and the U.S. to develop technology that helps reduce greenhouse gas emissions. Whether such an agreement has enough teeth to take a bite out of global warming is anybody’s guess, but it and other endeavors to fight global warming will undoubtedly pick up momentum with the release of the landmark IPPC report.

CONTACTS: World Wildlife Fund Australia drought report; Intergovernmental Panel on Climate Change, ; Asia-Pacific Partnership on Clean Development and Climate