The industrial age has seen carbon dioxide concentrations in the atmosphere increase to levels never before seen on earth. The culprit for these enormous increases is the burning of fossil fuels (see Fig. 1). So how will this dramatic change of in the composition of the atmosphere effect our planet? The media likes to focus on the negatives, such as the greenhouse effect and global warming, but recent research has shown there are some positive outcomes, namely a phenomena known as "carbon fertilization". This paper aims to compare these positive and negative outcomes and determine whether one will outweigh the other.
To better understand issues relating to carbon dioxide in the atmosphere, it is necessary to be familiar with the carbon cycle. Carbon exists on the earth in many different forms - as carbon dioxide in the atmosphere, deposits of coal, oil or gas, or in living organisms. Carbon enters the biotic world primarily through a process known as photosynthesis, which will be explained fully later on. It returns to the atmosphere through respiration, decay and burning. A unique process known as ice-core research has allowed scientist to accurately estimate levels of gases in the atmosphere for nearly the last 1 million years. Put simply, ice-core research involves drilling deep into the glacial ice in places such as Greenland and Antarctica and analysing the air trapped in the ice. This research shows that carbon dioxide concentration in the atmosphere has remained relatively constant up until about 300 years ago. Since CO2 measurements started in the late 19th century, CO2 levels have risen 20% (Kimball, 2001). The huge increased burning of fossil fuels has seen carbon being taken out of its solid state of oil and coal and transformed into its gaseous state as carbon dioxide. Mans interruption to the carbon cycle has put the system out of balance. The environment simply cannot cycle through this huge amount of CO2 quickly enough, and this results in increasing concentrations of CO2 in the atmosphere.
