1. Production and usage of carbon dioxide: an equilibrium Human beings and animals produce carbon dioxide when they exhale. Plants use carbon dioxide for their photosynthesis. They produce O2 and starch. The air in the atmosphere consists of mainly Nitrogen and oxygen. Carbondioxid can only be found in very low concentrations. Natural cycle, an equilibrium Presentation by Thomas Seilnacht. Translation C. Uphues

2. The natural greenhouse effect Solar radiation (short waves) enters the atmosphere. The solar radiation is absorbed by the Earth‘s surface and warms it. Thus short wave radiation is transformed to long wave radiation (infrared) which results in warmth. Atmosphere is warmer, Earth liveable. Water molecules are a greenhouse gas as well. Greenhouse gases absorb and re-emit the infrared radiation.

3. The human-caused greenhouse effect Fires, combustions produce CO 2 Water and CO 2 are produced. Short wave radiation changed to long wave infrared radiation. The radiation is absorbed. Atmosphere becomes warmer. Distribution of greenhouse gases Solar radiation enters the atmosphere The warming radiation remains in the atmosphere