The words on everyone’s lips when it comes to carbon are greenhouse gas and global warming.
Aside from CO2, methane is also a greenhouse gas – that is, it has the potential to increase the Earth’s average temperature. Greenhouse gases are responsible for the Earth being about 33 degrees Celsius warmer than it would be without them. The issue arises when the otherwise slow, natural development of global weather patterns is significantly speeded up by the burning of fossil fuels. The receding of the North Pole ice (from the yellow line):
A seemingly small increase of several degrees Celsius can have vast effects on the Earth’s crop plants, insect pests and wild plants and animals.
For example, the life cycle of many insect pests is tightly regulated by temperature. A very finely tuned heating up or cooling down triggers development and reproduction. The result of warming is a faster life cycle which means that instead of one generation arising yearly, there might be two or three generations arising yearly instead. This poses problems for the protection of crop plants.
Another example is the redistribution of wild animals. Changes in temperature cause migrations towards the poles of the Earth, and increased desertification at the equator. Pollen in North America has been shown to become increasingly allergenic:
The susceptibility of various parts of the world to be desertificated has also been projected: