The eruption of Eyjafjallajokull in Iceland could mean some good news for those of us concerned with understanding the science of climate change.
As volcanoes go, this is small stuff. The last volcano to have a substantial effect on global climate was Mount Pinatubo which erupted in the Philippines in 1991. Volcanoes affect global climate largely because the sulfur gases that they emit oxidize in the atmosphere to form sulfate aerosols (fine particulate matter), which stay around in the stratosphere for at least 12 months, and act as a strong cooling agent. According to the National Oceanic and Atmospheric Administration (NOAA), Mt. Pinatubo caused global temperatures to dip by about 0.5 degrees Centigrade for a year. The ash, which has been of concern to airline passengers in Europe and many others across the globe recently, generally has only a small and local effect on climate –it tends to fall to earth in a matter of weeks.