Forecasting the volcanic ash plume of Iceland's volcano
The eruption of Iceland's volcano with the unpronounceable name, Eyjafjallajökull, has virtually ceased over the past few hours, with ash only reaching up to 6,000 feet (1800 meters), according to the latest advisory from the UK Met Office. Lightning images from UK Met Office show no new lightning strikes from the volcano's plume since midnight local time today. The relatively small amount of ash present at low altitudes will probably not be able to make it all the way to mainland Europe before falling to the surface and dissipating, since 6,000 feet is below the altitude that the strong winds of jet stream blow. Wednesday through Sunday, the volcano emitted a towering cloud of volcanic ash 6 - 11 km (20,000 - 36,000') high in the air from its 1666 meter (5500') high peak. The jet stream blows strongly at that altitude range, which allowed for efficient transport of the ash cloud to mainland Europe.
Figure 1. Lightning lights up the night sky in this photo of Eyjafjallajökull's eruption taken on April 16, 2010. Ash particles colliding together separate electric charge, much as ice particles in a thunderstorm do, leading to spectacular lightning displays. Image credit: Marco, Fulle, Stromboli Online.
Forecasts of the movement of the ash cloud are made using trajectory models, which have a number of uncertainties to consider. Firstly, the amount of ash ejected by the volcano is highly uncertain, since our measurements of this quantity are limited. Secondly, the models must compute how high the ash cloud will rise (plume rise), based on the best available measurements of atmospheric stability. Since upper air-observations are taken just twice daily by a very coarse network of balloon soundings, our knowledge of the stability is rather crude. Finally, the trajectory models use forecast winds from a global model such as the GFS model to predict where the plume may go. The forecast winds from this model do not capture much of the complicated structure of the wind field over Europe, leading to a rather fuzzy approximation of where the ash will go. Nevertheless, these models have in general done a respectable job forecasting where the ash from Eyjafjallajökull will go over the past few days.
Figure 2. Cross section of the atmosphere over time over Paliseau, France, on April 16, 2010, as observed using ground-based lidar. Image taken using a 532nm cross polarization NFOV telescope. Note how the ash layer sinks closer to the ground as time progresses, as gravity makes the ash sink to the ground. There may also be some atmospheric subsidence occurring (downward moving air due to large-scale atmospheric processes.) Image credit: Ray Hoff, World Meteorological Organization's Global Atmosphere Watch's Aerosol Lidar Network (GALION).
For the next few days, these models continue to indicate that northwest winds at the jet stream level will continue to affect Iceland. As a result, Spain, Portugal, and Greece will offer the best locations to fly from. The northwesterly winds are expected to continue for the remainder of the week, thanks to an upper-level trough of low pressure over northern Europe. On Saturday April 24, the ECMWF model predicts that the trough will slide eastwards, and a ridge of high pressure will build over Europe. This will bring upper-level winds out of the southwest to Iceland, directing any volcanic ash northwards over the North Pole. Thus for the remainder of this week, expect continued ash clouds over much of Europe if the volcano resumes significant eruptions. But by next Sunday, the ash over Europe should decline considerably. For the latest one-day forecasts of where the ash cloud is expected to go, consult the UKMET Office. The Rhenish Institute for Environmental Research at the University of Cologne also has some excellent simulations from an atmospheric dispersion model of Eyjafjallajökull's eruption plume. The Norwegian Institute for Air Research runs a computer trajectory model called FLEXPART that has 1-day forecasts showing a cross section of the atmosphere. NOAA's Air Resources Laboratory (ARL) lets you perform your own model run using their HYSPLIT model, going out up to 48 hours, using the GFS model as input.
Figure 3. NASA's Aqua satellite captured this image of the eruption at 1:20 UTC on April 17, 2010. Image credit: NASA Earth Observatory.
Links
An excellent source of links of information on the eruption is available at http://islande2010.mbnet.fr/2010/04/eyjafjallajok ul-links-liens-a-propos-de-leyjafjallajokul/. My post on Thursday discusses the likely non-impact of this eruption on Earth's climate. Finally, we need to be keeping an eye on earthquake activity at the dangerous Katla volcano next to Eyjafjallajökull. If that volcano blows, it could mean dwarf the headaches caused by Eyjafjallajökull.
Jeff Masters
Reader Comments
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U guys realize the "El Nino" is supposed to be the Christ child, and you know what happened to Him.... sure he died.... but a few days later he was back.....
"I'll be back...."
SarahPalinU5A
1. The liberal media wants us to believe a volcano in Iceland is disrupting air travel. Everyone knows Iceland is too cold for volcanoes. 43 minutes ago via web
- more than 35 ft above sea level (or higher, depending on the actual geography)
- steel-reinforced concrete construction with hurricane stress truss tiedowns and minimal windows
- inner "safe room" area with mimimal direct wind impact.
Actually, in FL and along much of the GOM I'd assume the best choices to fit these criteria would be schools. However, if I take our own school-building practices here as an example of what schools might actually be like, I can see where my assumption might not automatically be a correct one.
Cat 5 @ landfall is the one time when u can be sure wind damage will be equally as bad as surge damage.
I simply do not have the words to express how much I enjoyed this...
That's a return rate of about 28 years.
Can anybody else identify other storms with landfall locations in the ATL basin that made landfall as cat 5? [For some reason I'm thinking Janet that hit Belize / Mexico.]
Allen, Gilbert, Mitch, Wilma off the top of my head.
150 Pernts
Off the top of my head....
Of course 2007 Dean in Mexico and Felix in Nicaragua.
Anita - 1977 - Mexico
David - 1979, Dominican Republic
I'll keep thinking.
And those too.
Two very recent ones.
Category 5 Hurricane Dean, Costa Maya, Mexico.
Category 5 Hurricane Felix in Nicaragua
Both 2007
KATRINA PART 2 PHOTO INDEX COVERAGE AREAS
Link
They didnt make landfall as Cat 5's though...
1928 Okeechobee Hurricane
1932 Bahamas Hurricane
1935 Labor Day Hurricane
1947 Fort Lauderdale Hurricane.
Hurricane Janet
Hurricane Beulah
Hurricane Camille
Hurricane Edith
Hurricane Anita
Hurricane David
Hurricane Gilbert
Hurricane Andrew
Hurricane Mitch
Hurricane Dean
Hurricane Felix
All storms that made landfall as a Category 5.
.."U betcha"..
Well..its kinda a trend if ya tink bout it a tad..
..just saying.
This picture always makes me laugh...
No she wasn't a Cat 5 at Cozumel.
I thought Gilbert did....but yeah the others no.
LOL Sorry Bord. Went and got something to eat. Didn't mean to leave you hanging. A guy in Iceland got them from the cam and posted them here. And now the cams are back opened for us. So much for an early night. ;>)
It was a Cat 4 at landfall.
AAAAAGGGGGGHHHHHHH!!!!!!!!
Actually Gilbert may have been a Cat 5 at landfall.
Well Felix, Dean, Gilbert, Anita, David, did make landfalls as Cat 5s.
Very true, I've rambled on here the past few years about how Wilma changed my life forever, at least financially. Coming in from the west coast of Florida, I thought nothing of it. Boy was I wrong.
The "Eyjafjallajökull frá Valahnúk" web-cam has some molten magma erupting, notice in the upper right-hand corner :o).
Is that a serious quote????
Because he's not really a Cat 5 in that picture....far from it. The NHC track says he was at the time but he wasn't lol.
Yeah that is annoying isn't it.
There are more than enough blogs on here for that...thanks.
obviously she doesn't know that Iceland is known as the land of "Fire and Ice"
The previous quote came from a "Sarah Palin U5A", not Sarah Palin.
Link to Palin's Twitter Feed:
Link
I apologize Levi and all the WU Bloggers!
Here it is 372 hours out:
384 hours out it also shows an area of low pressure with 1008MB located around 50 degrees west.
Be that as it may, back to CAT 5 HURRICANES OF THE ATLANTIC..... TWC special for the upcoming season? who knows....
Impact
16 people were reported killed, along with an additional 300 injured. All of this toll occurred in the Bahamas, notably on and around Abaco Island; damage estimates in dollars, however, were not released.[1]
[edit] Bahamas
The storm was very destructive on Abaco Island, where the reported barometric pressure was unofficially below 27.50 inches (931 mbar). On Green Turtle Cay, near Abaco Island, two brick churches were destroyed by the storm and winds were estimated by one resident to have exceeded 200 mph (320 km/h); some of the stone blocks from the churches were reportedly carried a half mile away.
I wonder if this was straight-line damage or embedded vortices...
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