Overview

In the 1970s and 1980s climate experts started to worry about the measured increase in the carbon dioxide content of the atmosphere. On the basis of the known principle of the greenhouse effect, it could be expected that the temperature on the earth would rise. It seemed likely that the change was the result of the sharp increase in the use of fossil fuels (coal, mineral oil and natural gas). In 1988, under the auspices of the United Nations (UN), the Intergovernmental Panel on Climate Change (IPCC) was set up with the object of interpreting and reporting on developments in climate research around the world. These reports were intended to serve as advice for the participating governments. The main task was to examine whether there was indeed any question of climate change and in particular of global warming. If that were to be the case, international agreements might be needed to limit the use of fossil fuels.

The principle of the greenhouse effect is as follows. The earth is heated by solar radiation. This penetrates the earth s atmosphere and warms the earth s surface. The surface of the earth reaches a certain temperature, and incoming radiation is compensated by outgoing radiation. The atmosphere plays an important role in this interchange, because it retains a portion of the outgoing heat radiation. As a result, the average surface temperature of the earth has a pleasant value of around 15 C. Incidentally, this is not caused by the air itself, but mainly by the...