Botany is being brought into play in the effort to understand and respond to climate change. Global warming is climate change that is producing a dramatic rise in temperatures around the Earth. Carbon dioxide, methane, and nitrous oxide are naturally in Earth's atmosphere in small amounts; however, they act as greenhouse gases by absorbing some of the long wave radiation that is radiated from the Earth back into outer space.
Sunlight is mostly shorter-wave radiation. Although the layers of the upper atmosphere block some, the portion that strikes the surface of the Earth warms both the oceans and the Earth's surface. However, the polar ice caps and the alpine glaciers of the world reflect much of this radiation. That which heats up the rocks of deserts, or the concrete and brick buildings of urban areas, or even the masses of greenery in forests is absorbed, in part, and returned as a part of cooling as long-wave infrared radiation. Most radiated heat returns to outer space. However, some is retained by the greenhouse gases and radiated back to the surface of the Earth.
The greenhouse gas phenomenon is natural. Without it, Earth would be much colder, by 54 or more degrees F (30 or more degrees C), and would very likely be a block of ice. What is of great concern at the present is that humans are causing global warming. The term anthropogenic is used to describe the human emissions of greenhouse gases, mainly carbon dioxide, that are causing a rise in global temperatures, the melting of the ice caps and the alpine glaciers, and a change in wind patterns that bring rain.
Was this article helpful?