Global Warming: Causes and Effects

Global warming, agree Professor James J. McCarthy, Dr. Paul Epstein, and journalist Ross Gelbspan, is an undeniable reality with acute consequences for environment, health, and economy.
Three distinguished panelists presented evidence for causes and effects of global warming at the AMP 167 seminar “Climate Change and Global Energy Futures” on Wednesday, October 14 at McCollum 101. James J. McCarthy, Professor of Oceanography at Harvard and former Chair of the Intergovernmental Panel on Climate Change, started off by outlining the geothermal evidence for warming, as well as the geological consequences of warming.

The Greenhouse Effect is occurring on our planet said Professor McCarthy, as a result of our having put more “insulation in the attic” via heat-trapping gases such as carbon dioxide, methane, and nitrous oxide. There is “no debate” in the scientific community, he said, that global warming is a real change and is linked to these greenhouse gases – especially carbon dioxide, which has a 100 year lifespan in the atmosphere – because carbon dioxide levels and global temperature undulate at the same pace and magnitude over time.

It is hard to point to one factor as the sole reason for global warming, explained Professor McCarthy, but “if you combine all of the anthropogenic effects, you can” and reliably reconstruct the 140 year surface temperature pattern, it reveals that four of the warmest years on record have all occurred within the last six years. Moreover, as climatological data shows, the rate at which the earth is currently warming has been the fastest among any 100 year period recorded.

These changes have had clearly observable effects on the globe, said Professor McCarthy, as well as consequences for energy harvest. The polar ice caps and Arctic tundra are melting, he showed in a series of slides, leaving wide spaces of water where there was once solid ice. This means, McCarthy warned, that ice platforms that were once strong enough to hold petroleum oil rigs are no longer able to support the heavy machinery, or worse, are no longer there at all. Although current projections hold that it is unlikely to happen, said McCarthy as he concluded his remarks, if the ice atop Greenland melted entirely, sea levels around the world would rise ten meters.

Professor McCarthy was followed by Dr. Paul Epstein, from the Center for Health and the Global Environment at Harvard Medical School, who described the health and economic effects of global warming. He started by outlining the systemic shifts in climate that have altered weather patterns and intensified disease spread. Climate change, human contributions, biosystemic effects, and extreme weather, he said, are contributing to worrisome findings like the 1991 case of cholera among the plankton in Peru – a story picked up by the Wall Street Journal for its potentially deleterious effects on shrimp fishing, tourism, trade, and travel.

“We have to understand hurricanes in Florida, and …the heat waves in Europe as integral [functions]” linked to the rapid rise in the rate of carbon dioxide growth, exhorted Dr. Epstein. The drought in the Western regions has been the worst in 500 years, he emphasized, and heavy rain events are up 20 percent in the same period. “These are facts,not models.” Dr. Epstein pronounced. So also, he added, was the spread of mosquito-borne and rodent-borne diseases, and the marked increase in respiratory ailments such as asthma over the last decade, both realities supported by global warming-induced weather pattern fluctuation and environmental change (e.g. Common allergen ragweed multiplies under increased carbon dioxide conditions.)

The kicker, said Dr. Epstein, is that the sum total of these systemic changes in climate, weather, and environment causes surprises like wildfires, crop failures, and deaths that severely burden economies around the world. In particular, he emphasized, the insurance industry would be hit increasingly hard if current patterns held: Insurance losses due to weather accounted for $4 billion per annum in the 1980s, but ballooned to $60 billion in 2003. Moreover, Dr. Epstein warned, “Things are happening so fast that we don’t know what will happen.”

The panel concluded its prepared presentation with Ross Gelbspan, whose recent book Boiling Point caps off his longtime journalistic and editorial focus on global warming and describes the possible remedies that can be found in political, business, and even journalistic spheres. Mr. Gelbspan led into his remarks with the pronouncement that although we face threats such as terrorism and a “trick-or-treat economy” today, “climate change is the issue that will swamp all other issues” in the coming years. If current
geo-political systems are left unchecked, he said, climate issues would eventually “tear holes in the global economy.”

There is “virtually no debate on this issue outside of the United States,” said Mr. Gelbspan, arguing that a 60 to 80 percent reduction in the use of fossil fuels is necessary to rein in the speed of global warming. Holland, for example, has committed to an 80 percent reduction of greenhouse gas emissions over the next forty years, and the British and the Germans have made similar commitments. The United States, on the other hand, continues to subsidize $20 billion in fossil fuel use.

Mr. Gelbspan proposed that the United States adopt the “elegant” G8 proposal, whose goal is to reduce emissions by 60 to 80 percent, by shifting subsidies to wean the national economy away from fossil fuel use, by supplying means of renewable energy production to developing nations, and by instating a carbon tax of 0.25 cents per dollar, among other remedies. It would not be difficult to regulate these activities, claimed Mr. Gelbspan. Energy trading is already monitored by banks, so administering a carbon tax would not require the extension to bureaucratic structures, and greenhouse gases such as sulfur dioxide come from “2,000 smokestacks in the Midwest,” he said.

Such changes are necessary, said Mr. Gelbspan, to avert a disastrous collision with “nature’s deadline” that could cause climate change to “bankrupt the economy” by the year 2065. Furthermore, he said, the changes carry economic boons like millions of new jobs in new markets and in existing ones, both domestic and abroad. Developing countries, Mr. Gelbspan noted, would be particularly helped: “Economists tell us that every dollar invested in energy in developing countries produces way more jobs and way more wealth than a dollar invested in any other sector.” Renewable energy production would enable developing nations to build their economies without the dual threats of prohibitive costs and emissions caps associated with fossil fuel use, he concluded.

All changes are within industrial reach, said Mr. Gelbspan, but need to be regulated centrally. He cited unnamed oil industry executives as willing to participate in the crossover to renewable energy, but only if a central regulator stepped in to guide the market through the political instability. Gelbspan also alluded to recommendations he had made to Middle Eastern oil producing nations to build infrastructure for hydroelectric power production as a hedge against the day when their fossil fuels run out. A well-managed and equitable energy production capability for the world, he ended by saying, would serve as the critical underpinning for global peace as well.