An automated volcanic ash dispersion model was developed to forecast the transport and deposition of volcanic ash. The model was verified using remote sensing data, ground-based measurements, and airborne samples. Further work aims to improve the model through better characterization of ash properties from additional data collection and source term modeling. An international collaboration was also formed to integrate earth observation satellites, ash detection networks, and dispersion models to develop an operational volcanic ash prediction system for Ireland and Europe.

1. Development of a
volcanic ash
forecasting model
Damien Martin
28th June 2012
School Institute Name to go here

2. Background
Icelandic volcano Eyjafjallajökull (first started on the 20
March 2010 –
second eruptive phase 15th until 20th April 2010)
The total loss for the airline industry was estimated at US$1.7
billion (IATA)
What made this volcanic activity so disruptive to air travel?
1.The volcano's location is directly under the jet stream.
2.The direction of the jet stream was unusually stable at the time
of the eruption's second phase, maintaining a continuous south
easterly heading
3.The volcano's explosive power was sufficient to inject ash
directly into the Jet Stream
School Institute Name to go here

3. Background
4. The second eruptive phase took place under 200 m
(660 ft) of glacial ice. The resulting melt water flowed back
into the erupting volcano which created two specific
phenomena:
The rapidly vaporising water significantly increased the
eruption's explosive power
The erupting lava cooled very rapidly, which created a cloud
of highly abrasive, glass-rich ash, this caused a large
amount of flights to be cancelled in Ireland.
Typically an encounter
every year- average of ~3
School Institute Name to go here

4. Volcanic Ash Advisory Centre (VAAC)
A Volcanic Ash Advisory Centre (VAAC)
is a group of experts responsible for
coordinating and disseminating
information on atmospheric volcanic ash
clouds that may endanger aviation.
The individual VAACs are run as part of
national weather forecasting
organisations
Met Office London Volcanic Ash
Advisory Centre (VAAC) provides
forecast guidance up to 24 hours
ahead to support decision-making
School Institute Name to go here

5. Regulatory response – London VAAC output
4mg/m3 –no fly zone
2-4mg/m3 – risk assessment required
0.2-2 mg/m3
Calculated at 3 flight levels
‘All concentrations are subject to a
level of uncertainty relative to errors
in the estimations of the eruption
strength’
School Institute Name to go here

6. What is that uncertainty?
Factor of 4-5
uncertainty
Height (km) in this
method!
Log eruption strength (kg/sec)
School Institute Name to go here

7. Motivation
‘ Questions have been raised about the level of sophistication of
the VAAC models used since much ash micro-physical and
chemical evolution processes are typically not present in
VAAC models. The development of an accurate and timely
forecasting model represents an important tool for Irish
government and policy makers in order to respond quickly
and efficiently to the impacts associated with volcanic ash
emissions. A more accurate forecasting may also lessen the
economic impact of such emissions.’
School Institute Name to go here

8. Model description
Three-dimensional on-line climate chemistry/aerosol model called REMOTE
(Regional Model with Tracer Extension)
Model Specifications
•81x 91x19 vertical grid boxes
•0.5 grid resolution (approx. 50 km2)
•6 h input and 3 h output resolution.
•Ash size distribution is constrained by the model to a lognormal Model Domain
distribution
PM10 emission rate data used for the simulations described here have been taken from the
European Monitoring and Evaluation Programme (EMEP, 2011) estimations. These data were
originally based on tephra estimates derived from preliminary thickness data obtained which was
measured on the 17th April at two locations 20 and 50 km east of the volcano.
School Institute Name to go here

9. Model Outputs
Low resolution mobile
standard spatial plot Vertical profile device version
School Institute Name to go here

10. Model
Automation
School Institute Name to go here

11. Verification- remote sensing and in-situ measurements
LIDAR (Light Detection
And Ranging) is an optical
remote sensing
technology that measures
properties of scattered
light to find range and/or
other information of a
distant target.
Plume entered the boundary layer
at 22 UTC 19 April 2010, SO4
increased from 23 UTC.
Ground measurements
with HR-ToF AMS
School Institute Name to go here

12. Model performance?
School Institute Name to go here

13. 20 year climatology study – (1990 – 2010)
Changing meteorological
patterns and increased
rates of deposition over
the winter period.
•Number of total column
execeedances for each of the
prescribed regulatory ash limits.
•Seasonal changes in ash height
profiles and its associated relationship
to exceedance of internationally
recognised flight levels.
•Calculation and tabulation of
regulatory exceedances at a number
of airports.
School Institute Name to go here

14. Irish response
Irish Aviation Authority (IAA)
MACCII project - Europe's Global Monitoring for
Environment and Security initiative
4-node (North-South-East-
West) ash detection network
covering the primary pollution
entry directions around Irish
airspace and airports. Ireland is
ideally positioned to develop,
test and implement a ground-
based remote-sensing ash
detection pilot network due to its
proximity to major Icelandic
volcanic sources
School Institute Name to go here

15. Volcanic Ash Strategic-initiative Team (VAST)
(funded by ESA)
Norwegian Institute for Air Research (NILU), Norway
Finnish Meteorological Institute (FMI), Finland
National University of Ireland Galway (NUIG), Ireland
ZentralAnstalt für Meteorolgie und Geodynamik (ZAMG), Austria
S&TCorp AS, Norway
To investigate satellite retrievals for volcanic ash
To evaluate and improve ash dispersion
To integrate Earth Observation Data and Models
To develop and introduce a volcanic ash prediction system
School Institute Name to go here

16. Satellite retrieval
They can be divided into two main types:
low-earth orbiting satellites in polar
configurations that provide global
coverage with rather limited temporal
coverage (typically twice per day) and
good spatial resolution (~1 km2),
and geosynchronous satellites that
provide very good temporal coverage
(up to 96 per day for some instruments)
but limited spatial coverage (70° total
field of view) and lower spatial
resolution (typically 10 km2).
For the aviation problem, the
geosynchronous satellites are much
better suited because the need for high
temporal resolution outweighs the need
for high spatial resolution.
School Institute Name to go here

17. NUIG component
• Validation of eruption source Information
• Evaluate specific source term models
The efficacy of utilising a one-dimensional volcanic plume model such as
PLUMERIA which incorporates inputs as vent temperature, radius and velocity, and
the effects of water/ice phase changes will be investigated. PLUMERIA outputs
graphs of velocity (from which eruption height is apparent), log density, plume
radius, temperature, and water/ice mass fraction as functions of elevation and
these values can be used to constrain the source term. This approach will then
be evaluated against more typical used empirical considerations of the source term
which may be subject to a high degree of uncertainty
• Validation of satellite retrievals
• Validation of modelling results
• Development of a certification process of ash products
School Institute Name to go here

18. Summary
An automated volcanic ash dispersion model was developed
and verified using both in situ and remote sensing techniques.
Further work has being instigated in order to better
characterise ash by improved modelling techniques and more
in situ measurements.
School Institute Name to go here

19. Acknowledgements
Colin O’Dowd, Harald Berresheim
Remote sensing In- situ measurements Modelling
Giovanni Martucci Darius Ceburnis Liz Coleman
Tomas Grigas Jurgita Ovadnevaite Saji Varghese
Jakub Bialek Robert Flanagan
Ciaran Monaghan Damien Martin
Aditya Vaishya
ICHEC (Alistair McKinstry) and the EPA for funding this
work
School Institute Name to go here