Evidences of Global Warming

 

- Glaciers have been gradually retreating over the last 200 years and are smaller now than ever before

- The seas north of Canada are usually frozen over everything northern winter and only partly break up over the summer

- Large coral reefs in the Caribbean are now permanently bleached. This happens when the water is too warm and the coral expels the  algae that give it colour

- The ice sheet in Greenland is getting thinner

- The number of alpine plant species found growing in the mountains in Germany has fallen, suggesting that it is now too warm for them to grow
 

More compelling evidence has come from the ice of Antarctica. Scientists collect ice cores from Antarctica by drilling into the ice. The deeper you go into the ice, the older the ice is, as new snow falls on top each year. When the snow falls, air bubbles are trapped in the ice. Analysis of these trapped gases reveals the amount of carbon dioxide in the atmosphere throughout history. So far scientists have drilled down 3.27 kilometres producing data about carbon dioxide levels going back roughly 900 000 years.