and this cloud also killed hundreds of thousands more in europe, according to john grattan. ow could an eruption in iceland affect people across such a vast area so far away? grattan: how on earth can these gases be concentrated sufficiently that you can taste them and smell them that they will burn your eyes over a thousand miles away? narrator: the answer to that lies not with laki's eruption, but with the weather. during the last week of june 1783 high pressure sweeps over northwest europe, bringing fine summer weather. but it also allows something foul high in the atmosphere to sink downwards. that's where the volcanic gases are. now they are being sucked down dragged down to the earth's surface, and it's like a blowtorch devastating the environment below it. narrator: the high pressure acts like a vast funnel. air spiraling down from the upper atmosphere brings with it laki's poisonous gases. if we were standing here in 1783, the view behind us would have disappeared. what we would see instead would be a blue haze across the landscape. the color green would disappear bec