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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Yes, but they are a component that is always there in the Caribbean no matter what. The only two components that are needed for a pre-season storm in the Caribbean are the existence of a tropical disturbance and favorable upper-level conditions. It is then, upper-level atmospheric conditions, which really determine whether we can get a pre-season storm.
Know what you mean. lol So are a lot of other people as per here. Maybe I'll not wait up until Iceland dawn tonight though and actually get some sleep. ;>)
You should invest and either purchase or manufacture yourself a 1/4" steel plate shelter, with Kevlar plastic windows, along with a ventilation shaft.
You can tow it to a safe location, drill fasteners into a concrete foundation, that will essentially guarantee your safety.
I get the first 'RIP' call of the year.
RIP El Nino!!
Even if there were steel cross-members inside to buttress the walls, what good would it be against missiles flying in 155-180MPH winds.
If a large piece of plywood was pushed through the center of a trunk of mature Palm tree, what would that piece of plywood do to 18 gauge steel?
It was a thought. But the flag-pole idea is not a real good idea.
compared to 2010, 1998 had quite an El niño, so we are already transitioning to La niña, well first comes neutral
yeah sorry for the stupid question, haven't been paying attention to the weather lately :S
Ok, where did you get that picture? Tell me, tell me, tell me, I am "fiending" over here!!
"I am El Nino!!! I can not die!!!!"
This one is still working pretty good. By the way, your Icelandic is pretty good.
Link
I see your point too. It is definitely cause for concern for an early start.
Not every building used as a hurricane shelter will survive a CAT 5 storm. You would need to be either in a concrete parking garage or in a steel reinforced concrete structure of some type.
Dude...if you get to that degree of desperation...you're already dead...
In the meantime, Wednesday through Fri/Sat should be warm but with low humidity in the wake of a front that'll quickly come through Tues night/Wed morning. That front will only be a dewpoint depressor(maximum temps will actually be slightly warmer behind the front).
The vulcano's name is Eyjafjalla, and it is under a glacier ;-)
I don't have Firefox, but I didn't even know they had a translator for Icelandic. It is a very complex language.
What doesn't make sense? If that's your only option...then you're out of options...somebody's gonna be collecting on your life insurance...
Awesome damage most likely done by the 20' storm surge.
got the iceland cams to work with this link got vala up you can see lava and lightening go to full screen look to the mid screen far right
er..the Surge there at the West End of the Hwy 90 Bridge in Waveland was 30 feet.
..just saying.
A Weather Underground 16 part series about Hurricane Katrina, by Margie Kieper.
Hurricane Katrina of 2005 produced the highest storm surge ever recorded on the U.S. coast--an astonishing 27.8 feet at Pass Christian, Mississippi. This bested the previous U.S. record of 22.8 feet, which also occurred at Pass Christian, during 1969's Hurricane Camille. According to the NHC Katrina final report (PDF File), Hurricane Katrina brought a surge of 24 - 28 feet to a 20-mile stretch of Mississippi coast. Fully 90 miles of coast from eastern Louisiana to Alabama received a storm surge characteristic of a Category 3 hurricane. The colossal damage that resulted has been documented by blogger Margie Kieper during a series of blog posts that ran in the summer of 2006. The contents are reproduced here, and consist of an introduction explaining why the surge was so large, and 16 parts exploring the damage done to each stretch of the Gulf Coast ravaged by Hurricane Katrina in 2005.
Lub da Glass tile..used to do that with my Dad
MSLP yayyy
as long as you're not challenging me to a 'bravery' contest...
We had several violated during Francis and Jeanne.. they were public schools and they had to move the people to a different wing during the storms. I don't think many structures are actually geared for a full bore cat five.. I saw what happened in Andrew and was shocked and awed. With that as my benchmark, I have concluded that there simply aren't many structures in Martin County Florida that would survive intact... and not only do I not live in one, but I am pretty sure I don't have access to one either. A shelter may be a better bet, but it's not a guarantee.
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...."
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