In 2020, net greenhouse gas (GHG) emissions in the United Kingdom (UK) were a little over 400 million tonnes (Mt) carbon dioxide equivalent (CO2e), of which about 320 Mt was carbon dioxide (CO2). The government estimates that emissions increased by 6% in 2021 with the easing of COVID-19 restrictions, about half of the increase being due to the extra road transport. The UK has emitted about 3% of the world total human caused CO2, although the population is less than 1%.