The most anticipated papal letter for decades will be published in five languages on Thursday. It will call for an end to the ‘tyrannical’ exploitation of nature by mankind. Could it lead to a step-change in the battle against global warming?Pope Francis will call for an ethical and economic revolution to prevent catastrophic climate change and growing inequality in a letter to the world’s 1.2 billion Catholics on Thursday. In an unprecedented encyclical on the subject of the environment, the pontiff is expected to argue that humanity’s exploitation of the planet’s resources has crossed the Earth’s natural boundaries, and that...