Atural Causes of Climate Change
atural causes of Climate Change
The Earth’s orbit changes a small amount once every 100,000 years. These are known as Milankovitch cycles
The amount of energy radiated from the sun changes over a 11-year cycle
Volcanic eruptions pump ash dust into the atmosphere causing a cooling effect
Large asteroid collisions can cause cooling as the material blocks out the Sun.
Asteroids hitting the Earth can cause huge fires which will release massive amounts of CO2 which will result in a warming effect.
Ocean current changes can cause cooling and warming.
Past Climate Change – The Little Ice Age
The Mini Ice Age was a colder period in northern Europe starting in the 15th century and lasting to the mid 19th century.
It had various negative impacts on people;
Crops did not grow well which meant people had to go hungry because there was less productivity and food.
The winters were very cold and the summers were very short.
It was most likely to be caused by natural changes, not humans because there was not enough people or industry to cause it. It could have been caused by:
Fewer sunspots
Volcanic ash in the atmosphere
We can retrieve this kind of information from diaries, newspapers and paintings from the time. Also by looking at tree rings in old trees can tell us what the climate was like. The tree rings in old trees are thinner during cold years.
During the Ice Age, Megafauna (big animals typically weighing over 40kg such as the woolly mammoth, giant beaver and sabre-toothed tiger) had evolved during the Ice Age.
Once the Ice Age had ended, temperatures rose 5oC in 10,000 years
The Megafauna couldn’t adapt to this change to a warmer climate and subsequently became extinct. Hunting by early humans could also be a factor in their extinction.
Present and Future Climate Change
Most people agree that humans are causing climate change through the production of various greenhouse gases.
The rise