Guardian: The eruption of the Eyjafjallajokull volcano is unlikely to have any significant impact on climate but has caused a small fall in carbon emissions, experts say. Although large eruptions such as Mount Pinatubo in 1991 can spew out enough material to shade and cool the planet, recent activity in Iceland is very small in comparison. The ash cloud has not reached the high atmosphere, where it would have the most effect, and it contains little sulphur, which forms reflective droplets of …