Oct 25, 2009

Global Warming Evidence: 20th Century Warming Superseded Natural Variation for Past 200,000 Years

We've always heard global warming skeptics ask for more temperature. But now, new evidence proofs global warming exists by logging temperature for 200,000 years! 

A recent study disputes the claim of global warming skeptics that the current rise in temperatures is explained by natural climatic variation.The credit goes to geologists from ScienceDaily, who have discovered sediments of insects and algae in a Canadian Arctic lake which are dramatically different from samples retrieved from previous warming intervals.

Skeptics point out that Earth’s natural temperature swings, moving from warm to cool, every few centuries because of tilts in the earth’s axis. Consequently, these skeptics claim, global warming is a hoax. However, the new sediment sample offers preserved climate data about the last 200,000 as opposed to 10,000 years for samples collected by scientists so far, which allows for more and accurate comparisons over the planet’s history.

The UB study shows that up until the 1950s, the varying ecology of the lake (rise and fall in temperature) was concurrent with variations during previous warming periods over 200,000 years, but soon after the mid of last century, ‘things really changed’, says Jason P. Briner, who led the research at UB.

During the last few decades, however, the ecosystem ‘is different from those seen during any of the past warm intervals’, indicating the effects of extreme carbon emissions, thus providing further evidence that global warming is a real phenomenon.

The Arctic sheet was formed 10,000 years ago, during the Ice Age, therefore climate data from that era gets preserved in earth’s sediments in glaciers. This lake was unique in the sense that glaciers did not ‘erode’ previous data.

The study, led by geologists in University at Buffalo (UB), was revealed in a paper titled, Recent changes in a remote Arctic lake are unique within the past 200,000 years, published by Proceedings of the National Academy of Sciences.

The research simply highlights the gravity of the situation a couple of months ahead of the UN Climate Change Conference in Copenhagen. 

SourcesScience Daily, US Geological Survey, ABC News
Home Page