US President Barack Obama made a last pledge on the environment in his eighth and final State of the Union address on 13 January.
Obama has been a staunch advocate for the environment since taking office, placing an emphasis on climate change and the threat it poses to the future of the human race, and indeed the planet.
Environmental issues have been a historically unpopular topic in the US. Despite that, Obama entered presidential office in 2009 with the help of green pledges. In 2015 he also made a notable, emotional impression around the signing of the Paris Climate Agreement.
He has made various environmental achievements in the US during his presidency - including the finalisation of the Clean Energy Plan, blocking the Keystone XL pipeline plans, and banning Arctic drilling,
Perhaps most notably in his final State of the Union address, Obama gave thanks to much of the nation for helping in the push for a greener America, whilst unabashedly scorning climate change skeptics.