Physical and human causes of climate changePhysical causes of climate change
Climate change is lasting change in long term weather patterns over a significant period of time. Climate change has positive and negative impacts and physical and human causes.
Physical causes of global warming and cooling include:
Volcanic eruptions - large amounts of volcanic dust in the atmosphere shield the Earth from the sun, lowering the global temperature. For example, the eruption of Mount Pinatubo in 1991 caused a dip in global temperatures
Milankovich’s Theory refers to differences in the tilt of the Earth in relation to the Sun. Every 41,000 years, there is a change in the tilt of the Earth’s axis. A greater tilt means more sunlight in Polar Regions
Over a 97,000-year cycle, the Earth’s orbit stretches, affecting the amount of energy received
Differences in solar energyThe energy received from the sun. - sunspot activity can increase or decrease global temperatures depending on which part of the sun is concentrating on Earth
Retreating ice caps release additional fresh water leading to changes in oceanic circulation
There has been a reduction in the albedo effect as reflection has decreased, because less snow and ice cover means more land is exposed
Melting permafrost releases large quantities of methane gas from decomposing organic matter. Methane is more than 20 times more effective at trapping heat than CO2. Methane accounts for 20% of the enhanced greenhouse effect
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.
