Research led by a Cardiff scientist has confirmed that the level of carbon dioxide in the atmosphere is directly related to climate change.
"We have now established that human activity is causing global warming,” Says Prof. Pearson of Cardiff University’s School of Earth and Ocean Sciences.
The team of experts from Cardiff, Bristol and Texas A&M Universities made the discovery whilst on an expedition to the remote East African village of Stakishari. They extracted hundreds of meters rock containing microfossils of plankton. Using these samples they were able to read the level of carbon dioxide in the atmosphere at a range of times in history.
"We wanted to look at climate change in the past so we could use it as a model for the future," Said Prof. Pearson.
The team’s findings confirmed that atmospheric CO2 started to decline about 34 million years ago, as the ice sheet began to form.
Geologists have long speculated that the formation of the Antarctic ice cap was caused by a gradually diminishing natural greenhouse effect. However, these findings are the first to provide a direct link and therefore confirm the relationship between carbon dioxide and global climate.
Prof. Pearson explained that this new information is particularly alarming when put in the context of today’s atmosphere. CO2 levels fluctuate naturally, which is why the ice caps have a cycle of growth and decline. Scientists have mapped the amount of CO2 in the atmosphere over the last 10,000 years revealing small natural changes - until the start of the industrial revolution, when it rises dramatically.
“The big worry is that this is just the beginning of the process of global warming. If nothing is done the situation looks very serious. We have the ability to stop it but we don't have much of a window of opportunity," Said Prof. Pearson.
The new findings will add to the debate about rising CO2 levels when the UN Climate Conference meets in Copenhagen later this year.