Drilling for Insight in Antarctica
The Scientific Consensus: We’re Altering an Ages-Old Climate Pattern
Julian Yu-Chung Chen in front of two 30" Apple Cinema Displays and a MacPro running Corelyzer, displaying high resolution core image along with sensor data plots.
“What we’re seeing from the body of results of climate research worldwide,” says Levy, “is that if you go back in time some five million years you will see a period when the earth was 2-3 degrees warmer than it is today. That was a natural occurrence, with no impact from humans. Looking at the natural cyclicity, we should be heading into a glacial period, starting to cool again. Instead, the earth is warming.” Many scientists see a clear correlation between today’s rising temperatures and human activity.
“We know that atmospheric carbon dioxide levels during past natural warm cycles were about 300 parts per million (PPM),” says Levy. “But we’re currently pushing the CO2 level up to 380 or 400 PPM, which is unprecedented over the last 400,000 to 500,000 years, even all the way back some 15 million years ago. Some models predict that CO2 may rise to 900 PPM over the next one to two hundred years. And if that does cause warming, we would expect to see Earth begin to behave as it did naturally thirty five million years ago when ice sheets first formed on Antarctica. The difference is that human activity appears to be contributing to climate warming.”
Findings from the 2006-2007 ANDRILL expedition indicate one thing clearly: projected warming of the earth’s climate will likely impact the current stable state of the Ross Ice Shelf. If as part of the current warming trend, the Ross Ice Shelf collapses – a distinct possibility – that could mean the loss of the West Antarctic Ice Sheet. And that, says Levy, could mean a sea level rise of up to 20 feet. The loss of the sea ice and the ice shelf, and the related impact on the formation of the cold, dense water beneath them will have a profound effect on the way oceans circulate and affect climate.
How soon and how quickly could all this happen? Nobody knows. But ANDRILL, and the many other studies that are part of the International Polar Year, may ultimately tell us much more about it.
