Vanderbilt Law Review

First Page



In 1958, Charles David Keeling began measuring the concentration of carbon dioxide (C02) in the atmosphere, at a site 11,000 feet above sea level near the top of Mauna Loa on the "big island" of Hawaii. The time series of monthly averages, the "Keeling Curve," is the iconic figure of climate change (see Figure 1). The curve oscillates and rises. The annual oscillations (whose details are seen in the Figure's inset) are the consequences of the seasonal breathing of the northern-hemisphere forests, which remove C02 from the atmosphere during their growing season and return C02 to the atmosphere as their leaves decay on the forest floor in winter. The steady rise--on average today, about 0.5% per year-is due primarily to the burning of fossil fuels. Indeed, the average rise would be twice as fast if all of the C02 released during fossil-fuel burning stayed in the atmosphere. Roughly half of the C02 emissions from burning fossil fuels stay in the atmosphere, one quarter go into the ocean (making it more acidic), and one quarter enter forests that, despite deforestation, are growing bigger.'