Natural changes in the sun’s activity or large volcanic eruptions have caused ancient shifts in the Earth’s temperatures and weather patterns, but over the last 200 years, these natural causes have not significantly affected global temperatures. Today, it’s human activities that are causing climate change, primarily due to the burning of fossil fuels like coal, oil, and gas. (IPCC)
Burning fossil fuels creates a blanket of pollution trapping the sun’s heat on Earth and raising global temperatures. (Global warming then leads to other changes like droughts, water scarcity, severe fires, rising sea levels, flooding, melting polar ice, intense storms and declining biodiversity.)
The more of this pollution, such as carbon dioxide (CO2), accumulates in the atmosphere, the more of the sun’s heat gets trapped, and the warmer it gets on Earth. There is a strong relationship between cumulative CO2 emissions and the increase in global surface temperature. (IPCC)
The amount of CO2 in the atmosphere has been increasing at an unprecedented rate since the Industrial Revolution, when manual labour began to be replaced by machinery fueled by coal, oil and gas. Today, the concentration of CO2 in the atmosphere is about 50 per cent higher than in 1750, far exceeding the natural changes over at least the past 800,000 years. (IPCC)
