The word “apocalypse” may sound overstretched but is not misused in relation to climate change. The Earth’s atmosphere is only favourable to life, human and other, because of a delicate balance of forces whose equilibrium could easily become unstable. “Apocalypse” comes from the last book of the New Testament, attributed to the mystic John of Patmos, sometimes also called the Book of Revelations. In an allegory full of extraordinary visions, of which the Four Horsemen of the Apocalypse are the best known, it describes how the world might end. This is a good time to update those equine prophets of doom.

Those horsemen represented the four principal dangers to life on Earth at the time St John was writing; the equivalents now would be somewhat similar: war, plague, and famine plus the fire and flood brought on by runaway climate change. War stands for all forms of human conflict and violence, not just state-on-state aggression but terrorism, racism, sectarianism and persecution, and the mass migration of people as a consequence. The refugees crossing the English Channel in small boats and the migrants trapped – disgracefully – between Poland and Belarus, are victims of conflict and oppression. Their plight is invariably made worse by political leaders who see them as pawns in a game rather than as human beings longing for the chance of a better life for themselves and their children.