Causes of climate change

Natural factors:
- Orbital changes: the Earth’s orbit is elliptical, and its axis is tilted, which changes the amount of the Sun’s energy reaching the Earth’s surface.
- Volcanic activity: volcanic eruptions release substantial amounts of sulphur dioxide, which blocks sunlight and temporarily reduces global temperatures.
- Solar output: the Sun’s energy output changes in an 11-year cycle. Increased sunspots lead to higher global temperatures.
Human factors:
- Burning fossil fuels: burning coal, oil, and gas releases CO2, accounting for 50% of greenhouse gas emissions.
- Agriculture: farming livestock and growing crops like rice produce methane, contributing to 20% of greenhouse gas emissions.
- Deforestation: felling trees for agriculture or logging increases CO2 levels because there are limited trees to absorb CO2 through photosynthesis.
- Industrial processes: manufacturing and chemical production release greenhouse gases like CO2, methane, and nitrous oxide.

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