DETROIT - Scientists disagree on whether global warming is caused by human activity, but the auto industry is not going to get caught sitting on its hands.
Industry speakers at a conference on climate change sponsored by the Engineering Society of Detroit on March 22 took pains to chronicle their efforts to cut emissions of airborne pollutants. The efforts range from helping suppliers cut manufacturing emissions to exploring new powertrains such as hybrids and fuel cells.
'We want to be known as leaders in this, not as followers,' said Gerry Fowler, director of supplier development at General Motors.
Researchers are having trouble directly linking increases in worldwide temperatures to automobiles or other man-made sources. 'Many of the causes of climate change are not too well understood,' said Timothy Kileen, a professor of atmospheric, oceanic and space sciences at the University of Michigan.
Based on the study of rocks and ancient ice samples, scientists know Earth's temperatures have fluctuated widely over the planet's history. Temperatures sometimes have risen or fallen rapidly within a human lifetime. Continental drift, sunspots and minute variations in the Earth's rotation and orbit are all believed to contribute to these changes, Kileen said. 'We expect the climate to be stable, but the answer is that it's not.'
Some scientists believe the rise in average global surface temperatures since 1890 of about 1.8 degrees Fahrenheit is linked to industrialization. But Kileen said that rise 'may not be outside the range of variability within the past 30,000 years.'
Nevertheless, the auto industry is facing mounting pressure to reduce production of the so-called greenhouse gases that cause warming in the atmosphere.
GM's Fowler says his company has created an environmental advisory team of suppliers to develop strategies for reducing the industry's 'environmental footprint.'
But there are limits. Neither Ford nor GM is requiring suppliers to become certified under ISO 14001, an international environmental standard for industry.