antarctic climate change.pptx

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By Alfie Graham Antarctic

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Page 1: Antarctic climate change.pptx

By Alfie Graham

Antarctic

Page 2: Antarctic climate change.pptx

Causes of climate change in the

Antarctic.

• As greenhouse gases accumulate in the atmosphere, more heat energy from the Earth's surface is intercepted before escaping to space, thereby causing the atmosphere to warm. Also, as climate change develops and increases, our O-zone layer is getting weaker and weaker which is letting in more heat rather then reflecting it back out into space, which will increase temperatures. And the heat will not be able to escape as the greenhouse gases intercept the heat and store the heat, ultimately increasing temperature.

Page 3: Antarctic climate change.pptx

Ice Cores

The beauty of ice cores is that they contain a variety of forms of evidence that can tell us so many different things about the past climate and environment. The evidence is also continuous through time and can be dated with a high degree of precision. Some important types of evidence and information are:* Stable isotope ratios of the oxygen and hydrogen making up layers of ice are used to

reconstruct the air temperature at the time that the snow fell.* Where annual layers of ice can be identified, the thickness of layers indicates the

yearly quantity of snowfall in the past. Which then can indicate to us if it was hotter or colder at that time.

* The concentration of dust preserved in layers of ice gives an indication of how much wind erosion was occurring on continents in the past which is related to both the strength of winds and the levels of vegetation cover over the land in the past.

* Tephra shards and levels of acidity of the ice show when major volcanic eruptions happened in the past.

* Air trapped inside the ice can be analysed for its concentration of carbon dioxide and methane, indicating how concentrations of these greenhouse gases in the atmosphere have fluctuated through time. So this can be used as evidence to show that climate change is getting worse as the ice cores show that the concentration of greenhouse gases is getting higher.

This is a slice of an ice core that has thousands of trapped air bubbles in.

Page 4: Antarctic climate change.pptx

Climate change graphs.

Page 5: Antarctic climate change.pptx

Sea Level + Albedo

*Global sea level rose about 17 centimetres (6.7 inches) in the last century. The rate in the last decade, however, is nearly double that of the last century. This is due to the ice melting in the Antarctic and Artic. Due to the increased heat from the increasing levels of greenhouse gases, the ice is melting at a much faster rate. Also, The snow and ice is usually good at reflecting the sunlight and deflecting some of the heat through the process of Albedo. However, recently due to the increasing temperatures, the ice has melted more, reducing the levels of Albedo, so as there is less snow and ice to reflect the sunlight and its heat, the ice will melt more and more reducing the Albedo levels even more, so it is a viscous cycle.

Page 6: Antarctic climate change.pptx

Extra Information from class.