As I mentioned in my previous post on this subject, Icelanders have been subject to high levels of sulphur dioxide from the Holuhraun eruption. The Met Office now predicts which areas of Iceland will be most subjected to the gas, but there have been times when it has supposed to be prevalent in East Iceland yet the gas has been detected in Reykjavik. Today, the gas is supposed to be tangible virtually all over the country, depending on the time of day.
The country has now bought more measuring gauges, 25 of which are supposed to be portable. But, in a situation where high levels of SO2 are expected to cover large areas of the country on the same day, these gauges need to be able to fly to keep up with the pollution! This is the forecast for the weekend:
Today (Saturday) gas pollution can be expected in the western part of Iceland.
Tomorrow (Sunday) the pollution will move to the southeastern part of Iceland.
There has not been much coverage of what high SO2 levels means if the eruption continues for a long time, as is expected, although precautions are publicized when high levels are expected in a particular area – in Höfn in East Iceland a few days ago, levels exceeded 6000 micrograms pr cubic metre, which is extremely high – and the Public Health people have a table of health effects on their website.
Update 27 September: Since I wrote this two days ago, the level of SO2 in East Iceland rocketed up to 21,000 micrograms per cubic metre. Yikes. And it could potentially increase even more.
I went to the lecture by Thorsteinn Johannsson from the Environment Agency earlier this evening. Various things came to light. One was that there are still large areas of Iceland where measuring gauges/meters do not exist. Another fact I discovered was that the small portable meters are by no means accurate. They measure 3oo, 600, 900 micrograms per cubic metre, and so nothing under 250 micrograms per cubic metre. And thirdly: it’s a good thing this is happening in winter, not summer, as then the effects on vegetation might be worse (but this eruption might well last into next summer, so be warned). On the other hand, measurements of H2S from the Hellisheidi geothermal plant show increased levels of the gas over winter, partly because of temperature inversions, and so the same may apply to SO2 as well.