Loss of Albedo - The white ice of the North and South poles reflects a lot of the sun's energy back out to space. When the sea melts, it is replaced with darker coloured water which absorbs more of the sun's energy and warms up.
The clouds of ash sent into the atmosphere by a volcanic eruption can cool the earth by blocking out the sun's energy. The volcanic eruptions in 1815 were so large that 1816 is known as the year without a summer.
Natural causes of climate change
Loss of Albedo
Reduction in volcano activity
The sun's activity varies between active and quiet over an eleven year cycle. These changes in activity can affect the climate down on Earth.
Changes in activity on the sun
Man-made causes of climate change
Oil, Coal and gas are burned to make electricity but this creates large amounts of CO2 in the atmosphere. This can come from making electricity or from factories.
Burning fossil fuels
Transport in general really. Cars, trains, planes and ships all burn fuel. When the fuel is burned, it creates greenhouse gases which add to the greenhouse effect.
In forests around the world (mostly rainforests), farmers are burning trees down to clear the land to create farmland. When the trees are burnt, this creates carbon dioxide in the atmosphere. Trees also breathe in carbon dioxide and breathe out oxygen so reducing the trees has an additional affect.
Burning trees to create farmland
Millions of sheep and cattle and pigs are kept on farms around the world to feed the world's population. These animals release lots of methane naturally, creating 13% of all greenhouse gases.
Remember - The greenhouse effect is not all bad, we actually need it to make Earth warm enough to live on. The problem is we have too much of it, it is increasing rapidly and shows no signs of slowing down.
Source: New Scientist
Definition of climate change
Climate Change or Global Warming?
Climate change refers to a significant and lasting change in the patterns of weather. Recently it has focused on changes in average temperatures and average rainfall caused by increased CO2 in the atmosphere.
Definition of global warming
An increase in average annual temperatures when measured on a global scale. Natural causes include a decrease in volcano activity and the loss of albedo due to shriking ice. Man-made causes include deforestation and a rise in greenhouse gases.
The ten warmest years in history have occured during the last 13.
What causes climate change?
In order of size:
Water vapour H2O
carbon dioxide CO2
Nitrous Oxide N2O
The greenhouse effect is a naturally occuring phenomenon that helps life to exist on Earth. The problem is that recently it has been strengthening and increasing rapidly in recent years. It shows no sign of slowing down or reversing back to previous norms.
What are the main greenhouse gases?
Climate change is caused by the greenhouse effect. Some chemicals in the air help to trap the sun's energy down on Earth. These chemicals are increasing and so the Earth is getting hotter.
To put it simply:
Is about the earth getting hotter.
Is about the changes which will take place as a result of global warming. It looks at what the changes are and where will they take place?
Average annual temperature 1880-2006