View source for Why energy usage serves as a good general estimate of carbon emissions

[[File:Emissions-by-sector-–-pie-charts.png|thumb]]
* The vast majority of [[energy]] comes from [[fossil fuels]].
* Until technology improves, renewables & nuclear are in very limited supply.
* Until technology improves, most road vehicles burn gasoline or diesel.
* Most goods are not manufactured in places with lots of renewables.
* Fossil fuels are responsible for most of the world's greenhouse gas emissions.

<small>Thus,</small><br />
When it comes to [[climate change]], [[energy]] usage is the main issue.

<small>Side note:</small><br />
When it comes to [[habitat loss]], [[land]] usage is the main issue {{light|(even though the CO<sub>2</sub> emissions involved are more moderate)}}.
{{minor|[[Food]] agriculture is the worst offender here, even though it uses only about 2% of the world's energy.}}