Natural Causes Of Climate Change

Question 1

What are the 3 natural causes of climate change?(SOV)

Answer 1

Solar output
Orbital changes
Volcanic activity

Question 2

What is solar output

Answer 2

• Sun spots can affect the amount of heat the sun gives off
• Sun spots are dark patches on the surface of the sun which makes it give of more heat
• The Sunspot cycle changes from a minimum to a maximum over a period of 11 years.

Question 3

What is the evidence that sun spots cause the climate to change?

Answer 3

Very few sunspots were observed during a cool period between 14th to 18th century. ‘The little ice age’

Question 4

How does Volcanic activity cause climate to change?

Answer 4

Short Term impact - volcanic ash blocks out sun, reducing temperatures

Long term impact - fine droplets of sulphuric acid ( sulphuric dioxide + water vapor) act like tiny mirrors reflecting solar radiation.

Question 5

What is a volcanic winter?

Answer 5

Cooling of temperatures from a volcano

Question 6

What is some evidence that volcanic activity affects climate change?

Answer 6

Eruption of Mount Tambora 1815

          - Most powerful eruption in 1600 years 
          - global temp fell by 0.4 - 0.7 degrees c
          - harvests failed - food shortages - famine caused 200k deaths

Question 7

What are the orbital changes that affect climate change?

Answer 7

3 Milankovitch cycles

       - Eccentricity
       - Axial Tilt
       - Precession

Question 8

What is eccentricity?

Answer 8

The path of the Earth’s orbit changes from circular to elliptical every 100,000 years.

Question 9

What is axial tilt

Answer 9

• Every 41,000 years the Earths tilt on the axis changes from 21.3 - 24.5 degrees.
• This causes the equator to move.

Question 10

What is Precession?

Answer 10

• The wobble of the earth.
• A complete wobble cycle takes 26,000 years
• Affects Norway - very long nights or days