Analysing the Global Carbon Cycle; The Interaction of Sources and Sinks

Why analyse the carbon cycle? Carbon is the central building block of all living organisms. On earth, carbon cycles in vast quantities through the atmosphere, biosphere and geosphere interconnected by pathways of exchange that undergo various chemical, physical, geophysical and biological processes. These exchanges are very complex and each process change has an impact on other processes within the cycle and on the total carbon balance. If an organism absorbs more carbon dioxide (CO2) than they emit they are known as a carbon sink. If they emit more CO2 than they absorb they are a carbon source.

Despite some recent press reports to the contrary, the vast majority of scientific evidence demon - strates that global warming is as a result of rising CO2 levels in the atmosphere. CO2 is a prominent greenhouse gas, acting as a blanket to prevent heat leaving the earth’s atmosphere. Research suggests that atmospheric CO2 levels have risen dramatically and at increasing rates in recent history and are now at their highest levels

in at least 650,000 years. Ice core measurements indicate that ambient CO2 was approximately 284ppm (parts per million) back in 1832. This increased to 350ppm in 1988 and is around 389ppm today.

If atmospheric CO2 levels continue to rise global temperatures are expected to also rise. Some reports suggest that a rise in CO2 to 700ppm would increase global temperatures by around 1.5oC, impacting on our

climate, ecology and social economics.

It is widely accepted that man-made activity, by burning fossil fuels, accounts for about 50% of atmospheric CO2. Natural biomass respiration and volcanic activity account for the remainder. Natural carbon sinks such as plant photosynthesis and ocean biota take up about half of this released CO2.

Increased uptake of CO2 by the world’s oceans has its own environmental impact as the seas become more acidic and so potentially damaging the marine life and ecology. There are also questions as to whether the oceans can sustain current CO2 uptake levels due to the effects of the climate change.

The concerns regarding rapidly rising atmospheric CO2 concentrations and its potential impact on future climate is an issue of global, economic and political significance. Much emphasis, therefore, is being placed on CO2 exchange research. Due to the complexities of these flux exchanges, the research draws on expertise from a number of geoscience disciplines requiring a variety of high quality and versatile gas exchange instrumentation. ADC Bioscientific is one of the world leaders in the development and manufacture of this environmental research instrumentation employed in carbon exchange research.