There are both natural and human sources of carbon dioxide emissions (CO2). Natural sources are an important part of a self-sustaining and functioning ecosystem and come from living things like animals and plants that release CO2 when they respire (i.e. breathing in oxygen and exhaling CO2). Human sources are the problem and come primarily from the burning of fossil fuels such as coal, oil and natural gas, as well as mass deforestation.
Human sources of carbon dioxide emissions have upset the natural balance that existed for many thousands of years before the influence of humans, because natural carbon sinks (such as the ocean, soil and plants) remove around the same quantity of carbon dioxide from the atmosphere as is produced by natural sources. This natural process had kept carbon dioxide levels balanced and in a safe range, but human sources of emissions have upset the natural balance by adding extra carbon dioxide to the atmosphere without removing the same amount.
Given carbon dioxide is a greenhouse gas that traps heat from the sun to warm our oceans and atmosphere; it plays a critical role in enabling life on this planet, keeping Earth at a liveable global temperature. The issue is that human-induced changes in the concentrations of carbon dioxide in our atmosphere — driven primarily by the burning of fossil fuels to produce electricity, or to heat and cool buildings, or to power machines — is changing the amount of heat that is trapped, causing dangerous global warming and climate change.
Global warming and climate change is dangerous in that it threatens the livelihood of our planet, animals, humans, and ultimately, life as we know it. Symptoms include melting of the polar ice caps, the rising of sea levels, the disturbance of animals’ natural habitats, animal extinction, extreme weather events, water and food shortages, and other negative side effects that are dangerous to the planet, to human and animal life, and to our future.
The planet's average surface temperature has already risen about 1.14°C since the late 19th century and most of the warming has occurred in the past 40 years, with six of the warmest years on record taking place since 2014. In order to avoid the worst impacts of climate change, the Intergovernmental Panel on Climate Change (IPCC) released a report stating we must reduce carbon emissions to the point where we hold global warming to no more than an additional 1.5 °C.
As humans, every aspect of our life is reliant on the natural environment. This includes the food we eat, the air we breathe, the water we drink, the clothes we wear and the products that are made and sold to create jobs and drive the economy. A healthy and stable climate is our most precious natural resource, and so as a global community, we must take our carbon footprint extremely seriously if we are to have a chance of achieving the 1.5 °C target.