Physical causes of climate change

Question 1

Milankovitch Cycles

Answer 1

Changes in the Earth’s orbit and tilt alters the amount of energy the Earth receives from the sun.

Changes in the Earth’s tilt happen every 41,000 years and a greater tilt towards the sun means more sunlight for polar regions.

The Earth’s orbit changes from being circular to elliptical in cycles of 97,000 years.

Question 2

sunspots

Answer 2

Global temperatures can be raised by peaks of sunspot activity which tend to happen in cycles of 11 years.

When the sun is more active, the Earth receives more solar energy which causes the temperature to increase.

Question 3

oceanic circulation

Answer 3

Retreating ice caps release additional fresh water into oceans which can lead to changes in oceanic circulation.

This can lead to changes in the distribution of heat around the planet.

Question 4

Volcanic eruptions

Answer 4

After volcanic eruptions, large amounts of dust and droplets of sulphur may reflect the sun’s rays, lowering the Earth’s temperature.