volcano

I can't really remember much about how mt st helens affected us..they say we had really cold weather..but i just can't remember..but now they are saying that the new volcano eruption in iceland could mean really cold weather for several years..cold summers, and cold winters..

we had a really cold summer and our coldest winter in 80 years..last summer and the winter before..here in Michigan..so I know how it affected our crops..

we had really good cold weather crops and the things in the greenhouse did OK but not great..but i do remember that my squash, cukes and melons didn't grow at all and the winter squash put on only a few small squash..

so i'm thinking..if they are right on the forcast of the volcano..maybe i need to be thinking "hoop houses" and more cold frames..and definately need to get that greenhouse moved..

any vocano comments or knowledge of how it should affect us would be appreciated.

The Eyjafjallajokull eruption has been pretty small so far.  It is mainly in the news because of the jet stream taking the ash over Europe.  Although, if it ciontinues in earnest the sulfur dioxide could cause a little cooling haze in the region (Scandanavia and Europe).  In 1783 the Laki eruption in Iceland caused problems in Europe, but that eruption was much, much bigger.  It was several times bigger than the 1991 Pinatubo eruption which caused about a 0.5 C cooler year and was much bigger than the current iceland eruption.

In the last year or so there have been eruptions just as big and larger in the Alutians and Kamchatka.  The ash plumes of those eruptions were easy to avoid so didn't make the news.  Add on top of those, the continuous eruptions of Etna, Erebus, Kilauea, and a few others each of which give off thousands of tons of SO2 per day.  And then there are a host of volcanos that have sporadic eruptions.  I would put the current eruption in this category of baseline eruptions that are always occuring and don't affect climate individually.

In the 90's I did volcanology work (measuring gas plumes, collecting samples, and loads of lab work), but couldn't stomach going on for a PhD so I moved on.  It was a lot of fun and these eruptions still pique my interest.  Sometimes we need to be reminded that nature can and will mess with human plans.

There might be some concern, though, if the neighboring larger volcano erupts (Katla).  I was just reading reports that Katla is showing some signs of 'waking.'  Guess we'll see what happens.  I do have plastic row cover for the garden, but need to get the greenhouse plastic to cover my hoop house frame.  Our climate is prone to frosts at any time during the year, even in mid-summer, so even a slight cooling of the atmosphere could have adverse effects here.

Kathleen

    Hmmm... might drive the temps back down for a few years...

Ash is created because the lava is touching glacial and cooling immediately.  Note that Hawaii's volcanos create almost no smoke, except when then they flow to the sea.

Antibubba wrote:
Ash is created because the lava is touching glacial and cooling immediately.  Note that Hawaii's volcanos create almost no smoke, except when then they flow to the sea.

I'm not sure that that is always the case.  There are places here in the West where the ash layers from old eruptions are many feet thick -- we are living on top of at least one such layer.  The ash is so fine it feels and acts like clay, but it really is volcanic ash.  Maybe those eruptions happened during the Ice Age, but some of the volcanoes are far enough south that they wouldn't have likely been covered with ice....

The explosivity of an eruption depends a lot on the chemical composition of the magma.  Except that nearly all magmas will be explosive when they come in contact with water.

Most of those big ash deposits in the western US were explosive because of their chemical composition (high silica; low iron, magnesium) and the magma contained high volatiles (water, CO2, sulfur, chlorine, fluorine).  There is a good chance the iceland eruption will return to being a scoria cone/ lava fountain when the glacier its under melts completely.  One of the report was that the glacier is 1/4 to 1/3 melted. Of course thing can change quickly, a few shifts of the earth and magma and the vent could move to another icy spot...

In previous Icelandic eruptions, the ash sometimes causes short term problems. The ash often contains lots of fluoride, which caused toxicity to sheep who grazed on pastures that got lots of ash.

In general, volcanic ash is a pretty good source of nutrients. Once the initial leaching occurs, they provide several centuries of high fertility.  In far away places like Europe, they might be getting an ounce or two per acre, which won't have a big effect.

very interesting, thanks..i did hear they are worried about the larger volcano next to it erupting too..but so far..so good..we did have friends stranded in europe for an extra week..hope they get home ok..left their 3 yr old with parents here.

The last globally-significant eruption was Pinatubo in the Philippines, back in the 1980s.  It lofted a huge amount of ash very high in the atmosphere, and it cooled the earth by about one degree for a year.  St Helens or Eyjafjallajokull  were minor in comparison.  There might be an effect on weather, but it might be too small to notice.

Sorry, I should have stated that the rapid cooking from ice is one factor.  You all are right about the different compositions of the magma.