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Impacts of climate change

Climate change is causing global temperatures to increase and average sea levels to rise.

Watch this video to find out how climate change is affecting rising sea levels in the Solomon Islands.

Causes of climate change

Temperature variations are caused by a combination of physical and human factors.

Physical causes

Physical causes of global warming and cooling include:

Variations in solar energy

  • result in the Sun emitting less energy. This reduces the global temperature.
  • raise global temperatures.

The Little Ice Age of 1650鈥1850 may have been caused by a decrease in solar activity

Milankovitch cycles

  • The Earth's orbit round the Sun varies in shape. Global temperature increases and decreases depending on close the planet is to the Sun.
  • The tilt of the Earth changes. More tilt means warmer summers and colder winters, less tilt has the opposite effect.
  • The Earth wobbles on its axis. This can change the timing of seasons and affect how big the range in temperature between high and low is.

Volcanic eruptions

  • Large quantities of in the atmosphere shield the Earth from incoming , lowering the global temperature.
  • Volcanic eruptions can cause warmer winters

Changing oceanic circulation

Changing can affect climate patterns and temperatures around the globe.

El Ni帽o is a current of warm water flowing from Australia to South America just below the Equator. It affects both Australia and North America. La Ni帽a affects Asia, South America and North America.
  • brings warmer, wetter weather to the eastern Pacific and can result in colder winters in the UK
  • brings cooler, drier weather to the eastern Pacific and can lead to more tropical storms developing in the North Atlantic.

Melting permafrost

Melting releases large quantities of gas. This adds to the natural greenhouse effect, increasing global temperatures.

All these physical causes of global temperature change have always existed and have been responsible for the alternating heating and cooling cycles of the Earth's temperature.

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