Global warming may be a reality, but the debate over what causes the warming and what to do about it is nowhere near over, according to a story in the latest issue of Chemical&Engineering News (C&EN) that surveyed climate scientists on both sides of the argument.

While both global warming "believers" and "skeptics" agree on some basics of climate change, for example, that average global temperatures have risen since 1850, with most of the warming occurring since the 1970s, the cordial agreement stops there, writes author Stephen K. Ritter. "At the heart of the global warming debate is whether warming is directly the result of increasing anthropogenic CO2 levels, or if it is simply part of Earth's natural climatic variation."

Most climate scientists maintain that man-made global warming is happening, the article states. This majority opinion has been disseminated in peer-reviewed reports over the past 20 years by the Intergovernmental Panel on Climate Change (IPCC), an entity established by the United Nations and the World Meteorological Organization.

Climatologist Michael Hulme of the University of East Anglia, in England, told Ritter that the scientific evidence backing the basic idea of human activity changing the global climate system is now overwhelming, even if scientific predictions for future climate change are still shrouded in uncertainty.

"It is vital that we understand the many valid reasons for disagreeing about global warming and climate change," Hulme says in the article. "We must recognize that they are rooted in different political, national, organizational, religious, and intellectual cultures –– our different ways of seeing the world.

"But we must not hide behind the dangerously false premise that consensus science leads to consensus politics," Hulme adds. "In the end, politics will always trump science. Making constructive use of the idea of climate change means that we need better politics, not merely better science."

However, global-warming skeptics argue that there is still a lot of guesswork in how scientists come to their conclusions. They take exception to the notion that there is a "consensus" agreement on the science –– that the science is settled and devastating man-made global warming is a foregone conclusion.

"The only contentious aspect of the IPCC assessment is attribution –– what is the cause of global warming and climate change," says atmospheric physicist S. Fred Singer, who is president of the Science&Environmental Policy Project, a public policy institute based in Arlington, Va. "We have looked at every bit of data that IPCC has brought forth, and we see no credible evidence for human-caused global warming. None."

In response to the latest IPCC report, Singer and other scientists formed the Nongovernmental International Panel on Climate Change (NIPCC). NIPCC is an international coalition of scientists convened to provide a "second opinion" on the scientific evidence available on the causes and consequences of climate change.

Citation: Stephen K. Ritter, 'Global Warming And Climate Change', Chemical&Engineering News, 2009; 87 (51): 11-21