Molten iron raining down like cowpats; ice floes at New Orleans. The weather of 1783 was an extraordinary case of sudden climate change driven by atmospheric gases. ‘Around mid-morning on Pentecost, June 8th of 1783, in clear and calm weather, a black haze of sand appeared to the north of the mountains. The cloud was so extensive that in a short time it had spread over the entire area and so thick that it caused darkness indoors. That night, strong earthquakes and tremors occurred.’ Thus begins the eyewitness account of one of the most remarkable episodes of climate change ever seen. It was written by a Lutheran priest, Jon Steingrimsson, in the Sida district of southern Iceland. At nine o’clock that morning, the earth split open along a 16-mile fissure called the Laki volcano. Over the next eight months, in a series of vast belches, more lava gushed through the fissure than from any volcano in historic times-15 cubic kilometres, enough to bury the whole island of Manhattan to the top of the Rockefeller Centre. Pentecost is the Christian festival celebrating the appearance of the Holy Spirit to the Apostles with the sound, the Bible says, ‘as […]