Tropic of Chaos_ Climate Change and the New Geography of Violence - Christian Parenti [2]
The IPCC has been attacked by climate-change denialists as alarmist and wrong because of several minor errors in its 2007 Fourth Assessment Report. Addressing these did not, however, change the report’s overall conclusions. In fact, because the IPCC operates on the basis of consensus, its conclusions are quite conservative, and its reports lag years behind the latest scientific developments. The IPCC represents the lowest common denominator of fully accepted conclusions from the scientific mainstream.
The IPCC has concluded that civilization’s dependence on burning fossil fuels has boosted atmospheric concentrations of carbon dioxide (CO2) from around 280 parts per million (ppm) before the Industrial Revolution to 390 ppm today. Analyses of ancient ice cores show 390 ppm to be the highest atmospheric concentration of CO2 during the last 10,000 years.2
Atmospheric CO2 functions like the glass in a greenhouse, allowing the sun’s heat in but preventing much of it from radiating back out to space. We need atmospheric CO2—without it, Earth would be an ice-cold, lifeless rock. However, over the last 150 years we have been loading the sky with far too much CO2‚ and the planet is heating up.
As the Pew Center on Global Climate Change explains, “The Earth’s average surface temperature has increased by 1.4°F (0.8°C) since the early years of the 20th century. The 11 warmest years on record (since 1850) have all occurred in the past 13 years. The five warmest years to date are 2005, 1998, 2002, 2003, 2007.”3
Less than 1°C warmer over a hundred years may not sound like much, but scientists believe it is enough to begin disrupting the climate system’s equilibrium. The negative-feedback loops that keep Earth’s climate stable are increasingly giving way to destabilizing positive-feedback loops, in which departures from the norm build on themselves instead of diminishing over time. The Greenlanad and Antarctic ice sheets—which reflect large amounts of solar radiation back into space and regulate the flow of ocean currents—are melting at rates much faster than climate scientists had predicted even a few years ago. The loss of reflective ice means more solar radiation is absorbed, and the world heats faster. Polar ice is melting rapidly, disgorging billions of gallons of fresh water, which alters the chemistry and currents of the oceans and, adding volume, threatens to raise sea levels by up to a meter over this century.4
The Social Challenge
Climate change is happening faster than initially predicted, and its impacts are already upon us in the form of more extreme weather events, desertification, ocean acidification, melting glaciers, and incrementally rising sea levels. The scientists who construct the computer models that analyze climate data believe that even if we stop dumping greenhouse gases into the atmosphere, CO2 levels are already so high that we are locked into a significant increase in global temperatures. Disruptive climate change is a certainty even if we make the economic shift away from fossil fuels.
Incipient climate change is already starting to express itself in the realm of politics. Extreme weather events and off-kilter weather patterns are causing more humanitarian crises and fueling civil wars. The United Nations has estimated that all but one of its emergency appeals for humanitarian aid in 2007 were climate related. Already climate change adversely affects 300 million people per year, killing 300,000 of them. By 2030—as floods, droughts, forest fires, and new diseases grow worse—as many as 500,000 people per year could be killed by climate change, and the economic cost of these disruptions could reach $600 billion annually.5
Rising sea levels will be one of the greatest stresses. In 2007, the IPCC projected that sea levels could rise by an average of 7 to 23 inches during this century. These numbers were soon amended, and scientists now believe sea levels will rise by an average