Climate change science
The Sun's energy drives the Earth's climate. The amount of energy received by the Earth varies due to changes in the Sun's activity and changes in the Earth's orbit around the Sun.
Annual mean total solar energy varies between the minimum and maximum of the 11-year sunspot cycle by about 0.1 per cent.
During the 20th century, the climatic influence of natural factors probably increased (a warming effect) up to about 1950 due to a period of low volcanism and a small rise in solar radiation.
Since the 1970s, global temperatures have risen significantly. Solar changes account for just a fraction of this recent warming. Rising concentrations of greenhouse gases are responsible for the bulk of the warming experienced in recent decades.
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