The emission of carbon dioxide caused by burning fossil fuels is considered to be one of the biggest ecological threats of our world. As a result, global warming of up to 5°C is postulated, with consequences such as melting the north and south poles or expansion of deserts, leading to gigantic flooding or famines of unparalleled proportions. On the other hands climate experts have predicted until recently a new ice area, and Hollywood has taken up that scenario in the movie The Day After Tomorrow. Undoubtedly, climate forecasts belong to the most difficult tasks given the many parameters that have to be taken into account, something we all experience on a daily basis, or do you trust your local weather forecasts?
The prediction of future global warming on earth is based on measurements of a temperature rise since the industrialization in the early 20th century that obviously correlates with a continuous increase of the concentration of carbon dioxide due to the burning of fossil fuels.
Carbon dioxide has been labeled as the greenhouse gas number one, and with the ratification of the Kyoto protocol its reduction has become one of the most important tasks in the world. Nevertheless, the effects of carbon dioxide on our climate are not as clear-cut as often depicted in the public. Especially the physical and chemical basics of the green house effect, which are generally ignored in public discussions, do not make it easy to agree with the predicted dramatic effects on our climate, ranging from drastic temperature rises with dire consequences for coastal regions to an irreversible climate catastrophe for the world within the next 13 years.
About half of the sunlight that falls on earth reaches the ground (Figure1) right, click for enlargement), from where it is thrown back in part as infrared light - what we feel as heat -, which spans a range of wavelengths from 1 to 40 µm (µm = micrometer = one millionth of a meter).
Some gases - so called greenhouse gases - in the atmosphere have the ability to absorb infrared light and this way hold back heat, resulting in a temperature rise on earth.
1)Source: UNEP - United Nation Environment Programme
