The Evidence

Evidence from the Cyrosphere

The Artic has reduced in ice by 30% and the thickness has reduced by a half since 1980.

Greenland's land ice is moving down to the sea twice as fast as previously which has a significant effect on the sea level.

Glaciers grow and shrink in response to climate for example Solheim Glacier in Iceland.

Ice core analysis

Where they are analyzing the ice is in Greenland and Antarctica. They measure by drilling down into the ice which is thousand of years old. The layers are the winter snowfall compressed into ice which can be analysed for temperature and the trapped gases (oxygen isotopes) can be analysed for carbon dioxide. The oldest ice core is called Vostok which is 400,000 years old.

Cross dating in trees

Climate conditions influence tree growth, patterns in tree-ring widths and density.In temperate regions where there is a distinct growing season, trees generally produce one ring a year, recording the climate conditions each year. Trees can grow to be hundreds to thousands of years old and can contain annual records of climate for centuries to millennia.