Humanity’s emissions of greenhouse gases have caused rapid global warming at a rate unprecedented in at least the past 2,000 years. Rapid global warming has been accompanied by increases in the frequency and intensity of heat extremes over most land regions in the past 70 years.
While human activities cause emissions of a number of greenhouse gases, carbon dioxide (CO₂) stands out as the leading culprit. This is because of its relatively long atmospheric lifetime and because human activities cause much higher emissions of CO₂ than other greenhouse gases.
To avoid reaching unsafe global temperatures, climate scientists have concluded we can’t prevent continued global warming without reaching a state of net zero CO₂ emissions.
