Why cold hard facts of
Until a few years ago
A new report, published today in the science journal, Nature, claims that changes in carbon dioxide levels in the atmosphere led to the creation of the Greenland ice-sheet, further evidence, experts claim, that carbon dioxide changes the nature of our planet.
The 12-month study, funded by the British Antarctic Survey, was led by scientists at
Among them was Dr Alan Haywood, based at the
"Given the issue of global warming and people wanting to know if the ice sheets are going to melt, we wanted to try and understand why the
Three million years ago,
Scientists discovered that the overwhelming cause was a drop in carbon dioxide levels in the atmosphere.
"This is significant because it's the one thing we are changing in the atmosphere at the moment through the generation of greenhouse gases," says Dr Haywood.
"We are not saying in the next 10 or 20 years we expect the
Carbon dioxide levels are now approaching those that existed when
"What these findings tell us clearly and eloquently is that we're playing with the one thing that appears to have the largest impact on the
But given the fact that
"It would cause sea levels to rise by about six metres, which doesn't sound much, but a lot of big cities like
Dr Haywood says that although scientists cannot predict how quickly, or slowly, ice levels will change, they do know what causes this change, and CO2 is a key factor.
"You can't understand how something is going to behave until you know why it's there in the first place. So understanding what caused the ice sheet to form puts us in a much stronger position to say that future CO2 increases will have a significant impact."
However, other research the same team is currently working on suggests that the
But he admits, too, that we are entering uncharted scientific territory. "The rate of CO2 increases we are seeing now are greater than anything we have seen in the geological record by some magnitude."
Which is why Dr Haywood believes the world needs to act sooner, rather than later.
"We need to establish a line that we don't cross even if there are no short-term repercussions.
"Is it ethical for a generation that recognises the dangers to then do nothing? I don't think history would look kindly on that. We have a responsibility to look after our planet and hopefully leave it in an even better condition for future generations."
The next step, he says, is to find out why carbon dioxide levels fell millions of years ago.
"We've found the bullet, now we have to find the smoking gun."