Climate Change- Physical And Human Causes

Question 1

Volcanic Eruptions

Answer 1

Reflect suns rays, lowering temperature

Mt. Pinatubo eruption in 1991, millions of tonnes of dust, lowering average temperature by 0.5°

Question 2

Retreating ice caps

Answer 2

Additional fresh water, changes in oceanic circulation

Reduction of albedo effect from reduction in reflection as more land exposed

Question 3

Melting permafrost

Answer 3

Methane released by melting permafrost from decomposing matter

Question 4

Milankovitch’s theory

Answer 4

Change in earths tilt every 41000 years
Greater tilt= more sunlight in polar regions

Over 92000 year cycle, earths orbit stretches (from circular to elliptical) which effects how much energy is received

Question 5

Higher demand for electricity

Answer 5

More CO2 released from burning fossil fuels
CO2 traps heat
Fossil fuels have been increasingly used to power factories, generate electricity and to heat homes

Question 6

Increased car ownership

Answer 6

More petrol and diesel required

Cars release nitrous oxides into the atmosphere which adds to global temperatures

Question 7

Increased demand for land in developing countries

Answer 7

Deforestation (especially amazon rainforest)= less CO2 absorbed and more being released from burning

Question 8

Peat bog

Answer 8

Peat bog reclamation causes additional CO2 being released into the atmosphere

Question 9

CFCs

Answer 9

Disused fridges release CFCs when foam insulation inside is shredded
Coolants used in fridges and air conditioning systems created CFCs which are safe in a closed system but can be released if not disposed correctly

Question 10

Rice and Cows

Answer 10

Large quantities of rice grown to feed growing populations (eg india) produces methane
Belching cows are increasing due to global demand for beef- this also adds to methane being produced

Question 11

Nitrous Oxides

Answer 11

Released from vehicle exhausts and power stations, have increased due to consumer/ electrical goods and vehicle use