Emissions by Source: What Sectors Create the Most Emissions?
9 minute read
Updated on Tue Aug 03 2021
Where do greenhouse gas emissions come from?
- By source - where the overall emissions are produced
- By end use - within each source what the emissions are used for
This chapter will look at the source of emissions. The next will explore which end products are most responsible. All of the data on both of these methods for measuring emissions can be summarised in one amazing chart:
The left side of this chart splits emissions into which sector they come from, e.g. energy, agriculture and waste. The right column of the chart shows emissions by end-use activities. This helps us understand the emissions released in the making of specific products and activities.
Which sector produces the most emissions?
Without including emissions from energy use, farming and land use change accounts for 14.8% of emissions (if we include emissions from energy use, this number is even higher!). This makes farming and land use change the next biggest source of greenhouse gas emissions after energy.
Actually all of these processes release greenhouse gases into the atmosphere!
This sector also includes emissions from land use changes. Trees and healthy soils tend to absorb more CO₂ from the atmosphere than they release. They are what's known as carbon sinks. But when forests are cleared for farms, roads and buildings, the carbon that is stored in them is released back into the atmosphere.
The next sector after agriculture is industry, which accounts for 5.9% of emissions. This includes emissions from producing cement, chemicals, and various other materials (like plastics, rubber and human-made fabric).
Waste in landfills, sorting wastewater and treating human sewage all produce greenhouse gases, especially methane and nitrous oxide. The largest source of these comes from landfilling of solid waste, including food waste.
So, we’ve seen which sectors release the most greenhouse gases. Now let’s look at which end uses/activities are responsible for these emissions.Next Chapter