Aurora and Ash

19 Aug 2011

NASAs Goddard Space Flight Centre spokesman Tony Phillips says the STEREO spacecraft in combination with new data processing techniques has succeeded in tracking a solar storm from its origin in the Sun's corona to impact with the Earth, resolving a 40 year controversy on the structures of space weather. There is a video that can be watched at which shows a CME event swelling into an enormous wall of plasma and then washing over the Earth. CMEs are clouds of solar plasma and create aurora and radiation storms (see also which has the same video.

Meanwhile, University of Leeds research on ash clouds from Icelandic volcanoes say that such clouds impact western Europe on average every 56 years (see ). A paper in Geology (August) analyses how many ash clouds may have occurred over the last 7000 years - but with the caveat this is a conservative estimate (once in 56 years). It could be somewhat higher as he used evidence of microscopic ash layers in lakes and peat bogs in Britain, Ireland, Germany, Scandinavia and the Faeroes, augmented by historical documentation. The 56 year frequency is an average - as they were found to occur at intervals as short as 6 years and as long as 100 + years. All in all it amounts to an awful lot of Icelandic volcanoes - and they are only the ones in which the ash fell on western Europe.