Mitigation of volcanic hazards using satellite- and ground-based radar
Submitting Institution
University of ReadingUnit of Assessment
Earth Systems and Environmental SciencesSummary Impact Type
EnvironmentalResearch Subject Area(s)
Physical Sciences: Astronomical and Space Sciences
Earth Sciences: Atmospheric Sciences
Engineering: Geomatic Engineering
Summary of the impact
Researchers at the University of Reading have developed and implemented
ground and satellite-based techniques that improve the monitoring of
impending volcanic eruptions and their aftermath. Our systems have been
mainly used in collaboration with the Montserrat Volcano Observatory (MVO)
and the local government civil protection committee on Montserrat. In July
2008 the early rescinding of a precautionary evacuation was made possible
by these techniques, thereby minimising disruption and lost economic
revenue. The deployment of a permanent, operational ground-based
instrument on Montserrat provides a capability that will reassure
inhabitants and the island's commercial sector of future timely warnings,
thereby enhancing their quality of life and allowing companies to return
to the island.
Underpinning research
The University of Reading (UoR) has a long-standing programme of work to
develop new methods of measuring the dynamism of volcanic activity and
incorporating these measurements into models that can be used to mitigate
the resultant hazards (such as Pyroflow2 for simulating the
paths of pyroclastic flows from the Soufriere Hills Volcano on
Montserrat). As part of this we have helped pioneer the practice of using
radars (on the ground and in space) to monitor the state of active
volcanoes, particularly those that are frequently obscured by cloud. The
ground-based radars were developed in collaboration with the University of
St Andrews (UoSA) and Lancaster University (LU) and the space-based radar
techniques with DLR (German Aerospace Center), Astrium (Europe's largest
space company) and ESA (European Space Agency). Prof. G. Wadge has been
with the Unit from 1985 to the present day. Wadge led the work at UoR with
contributions from PhD students H. Odbert (2004-8) and A. Toombs (2007-11)
(supervised by Wadge) and technical staff in the Unit.
The research comprised two complementary strands.
1. A ground-based millimetre-wave radar/radiometer, the All-weather
Volcano Topography Imaging Sensor (AVTIS) was proposed, built, tested and
deployed in a ten-year programme that began in 2000. This was funded by a
series of grants from NERC with Wadge as PI. AVTIS was specifically
designed for lava dome volcanoes such as the Soufrière Hills Volcano on
Montserrat. In conjunction with MVO, we demonstrated that AVTIS provided
data on the topography and temperature of the growing lava dome
independent of weather conditions, and provided changing hazard
information on timescales of hours to weeks.3,4,5 A second
generation of fixed and roving ground-based versions of AVTIS, was also
conceived, built, installed and tested by the Unit, in conjunction with
MVO. By 2011, a fixed AVTIS instrument provided continuous, 24-hour data
from the volcano and has been used operationally by MVO since. AVTIS is
the only such instrument in operation worldwide.
2. The application of space-borne synthetic aperture radar (SAR) for
volcano monitoring was developed over the last two decades. The Unit
played a significant role in this by helping to apply radar interferometry
to measure subtle ground motions on volcanoes (including the first mobile
ground-receiving station on Montserrat in 2000) and in using radar
intensity changes to monitor the emplacement of pyroclastic flows
(high-speed flows of hot ash, rock fragments and gas) and lava flows. In
the early 2000's Wadge helped design satellite missions in conjunction
with ESA and Astrium specifically for volcano monitoring. The Unit has
pioneered the use on volcanoes of very high resolution radar intensity
data from the TerraSAR-X satellite and in 2009-10 demonstrated for the
case of Montserrat how the location of explosive vents and recently
emplaced pyroclastic flows can be readily tracked in inaccessible and
cloud-covered areas 1,5, and in 2010-11 how the motion of lava
flows in Papua New Guinea could be tracked. 6 The high spatial
resolution and temporal frequency of these new datasets opens up a
valuable source of information on the dynamics of on- going explosive and
effusive volcanic activity that is of direct operational value to
observatory scientists responsible for making hazard forecasts.
March-April 2006 provided a valuable demonstration of the value of the
radar measurements. AVTIS measurements of the lava dome showed that an
increase in the rate of lava extrusion was occurring 4. This
was not detected by other MVO instruments until two days later. Thus AVTIS
effectively provided a 2-day improvement in early warning of an increased
level of hazard. This additional warning has been an important gain in
terms of planning emergency procedures.
1. Wadge, G. (2009) Satellites offer crucial data for volcano safety. http://bit.ly/1dFiNHa. For more
information about this source see http://www.scidev.net/en/content/what-we-do/
References to the research
Publications
The numbers of citations to each journal paper are given, as found using
ISI Web of Knowledge in October 2013. Another metric of the quality and
originality of the research is the fact that, following tests, the
ground-based radars and satellite information was put into operational use
by MVO and that the new systems are unique, being the only such
operational system in the world. The three main references for evaluating
research quality are marked with an asterisk.
Selected Research Funding
NER/A/S/2001/01001 (NERC, Standard, £282k) Measuring and modelling the
collapse of volcanic domes. (2002-2005) Wadge (PI), Pinkerton (Lancaster),
Smith (St Andrews).
NE/D00859X/1 (NERC, Urgency, £12k) Measuring the growth of the new lava
dome at Soufriere Hills Volcano, Montserrat. (Oct-Nov 2005) Wadge (PI),
Pinkerton (Lancaster), Smith (St Andrews).
NE/D001734/1 (NERC, Urgency, £37k) A time series of measurements of magma
flux at the lava dome of Soufriere Hills Volcano, Montserrat. (Mar-Apr
2006) Wadge (PI), Pinkerton (Lancaster), Smith (St Andrews).
NE/EO15352/1 (NERC, Standard, £368k) Measuring incipient lava dome
collapse. (2007-2011). Wadge (PI), Pinkerton (Lancaster), Smith (St
Andrews).
MVO contributed approximately £50K over ten years in the form of
laboratory use, staff time and helicopter flights for testing our radar
system.
Satellite data grants were made by DLR (German Space Agency) to the UoR,
together with MVO and Rabaul Volcano Observatory (Papua New Guinea):
GEO-0436 (DLR, TerraSAR-X, 40 images) Mapping morphological and
structural changes on a lava dome as a precursor to surface activity,
Soufriere Hills Volcano, Montserrat. (2008-2010) Wadge (PI).
GEO-0879 (DLR, TerraSAR-X, 22 images) Measurement of the rate of growth
of Bagana Volcano. (2010-2011) Wadge (PI).
Details of the impact
The eruption that began on Montserrat in 1995, and continues to date, has
resulted in 19 deaths (all in 1997), the emigration of two thirds of the
population and an estimated £1bn in economic costs 7, mainly
borne by the UK government.
Over this 18-year period, the scientific, governmental and social
responses to the volcano have evolved. At the start of the eruption there
was no observatory on the island, but now the MVO has a custom-built home
and a sophisticated network of monitoring instruments, that now includes
the radars developed by UoR, and warning procedures. The activity at the
volcano has waxed and waned, but one constant is that the main threat to
life has been from pyroclastic flows produced by collapses of the lava
dome that can grow for years on end. The short-term threat from these
flows largely changes depending on how fast the dome is growing (the
faster the more dangerous) and in which direction (the remaining populated
areas lie to the north and west of the volcano). MVO faced a major problem
in assessing these two hazard factors operationally: the lava dome at the
top of the Soufriere Hills Volcano is often covered in cloud, sometimes
for weeks on end. The Unit recognised the significance of this at an early
stage. Satellite radar data, that were of sufficiently high resolution to
play a useful role, were available only infrequently and under very
limited access. By 2000, the Unit had identified that some type of
ground-based, cloud-penetrating radar was required that could be focused
on the most dangerous parts of the lava dome. The development of AVTIS in
conjunction with MVO followed from that need.13 The development
to a second- generation operational version of this entirely new class of
instrument took ten years.
The ability to demonstrate an impact with AVTIS and with the
high-resolution civilian satellite radars (TerraSAR-X) has varied
depending on the state of activity at the volcano and the state of
development of the instruments.
A well-documented example of impact comes from July-August 2008. After
several days of earthquakes, a major explosion occurred on 29 July
depositing ash on inhabited areas of Montserrat. Unfortunately, cloud
covered the upper part of the volcano and MVO initiated an evacuation of
part of the island closest to the volcano until the state of the volcanic
dome could be determined, and asked for help from us to do this. AVTIS was
under development in the UK at that time, so we used satellite radar data
instead. Wadge invoked the International Charter on Space & Major
Disasters8,9 via the UK Cabinet Office on MVO's behalf. This
Charter gives privileged access to satellite remote sensing instruments
(radars mainly in this case) owned by all the major space agencies across
the world, to immediately focus on the crisis (Montserrat in this case)
and provide free data. In association with the British Geological Survey
these data were interrogated by us.15. The TerraSAR-X data
proved the most valuable and within 3 days of the explosion we were able
to provide MVO with clear evidence that the explosion had produced a new
vent but that this vent had not destabilised the dome as had been feared.
MVO reported this to the civil authorities on Montserrat and the
evacuation was revoked. It took another 10 days before the cloud lifted
sufficiently to confirm radar observations. This early "all-clear" was
welcomed by the evacuated inhabitants and boosted confidence in the
technique and the public's confidence in MVO. It also demonstrated the
UK's continued commitment to international disaster response and in
particular the application of space technology to this domain. It was
always the intention of this work to effectively transfer the technology
to MVO. As of 2011 both the space-borne and the ground-based radar
techniques are a routine part of MVO operations. No event has yet tested
the eruption early- warning capability but the deployment of a permanent,
operational instrument on Montserrat shows that the system provides a
capability for more advanced and timely warnings than was available during
the last major eruption in 2010.
The main beneficiaries of the impact are the people and the businesses of
Montserrat. In 2008 the government's Disaster Management Coordination
Agency (DMCA) deployed a radio-based early warning system to disseminate
information on the risk posed by the volcano to everybody in the areas at
risk.11 The island's population is estimated to be just over
5000 and is now growing by about 400 p.a. but has yet to recover to the
over 12000 estimated before the 1995 eruption.12 Prior to
then, the island had an export economy based on agriculture, clothing,
electronic parts, tourism, building sand and plants, with a GDP of £30m.
After the eruption GDP is now at about £15m and the DFID support for
2012/3 was £15m, which finances roughly half of all expenditure.12
It is very difficult to put a figure on the monetary impact of our
research because there has been no official audit of the impact of the
eruption from the Government of Montserrat and our work is, rightly, bound
up in the operations of MVO. The economic benefits in avoiding false
alarms and in the ability to generate earlier safe all-clears are
considerable as evacuations cause relocation costs and emergency
provisions costs and the commercial activities in affected areas to cease.
Since 1997 there have been no deaths due to the volcano. The constant
effort at MVO to forecast impending hazards and judge local risks has been
helped by our work both to avoid tragedies and engender justified
confidence in public safety. As noted in a report10 financed by
the European Commission (EuropeAid Cooperation Office) "The Montserrat
Volcano Observatory provides the Government with an organisation for
managing this [volcanic] environmental hazard, and ensuring the continuing
safety of the island's inhabitants." The importance of the volcano early
warning capability is stressed in the Montserrat Sustainable Development
Plan.16
Social science studies in relation to Montserrat show the advances in
monitoring and prediction have led to an improved quality of life for many
inhabitants, given they now have the knowledge that they will receive
reliable early warnings of a major eruption and will not be subject to
unnecessary evacuations: for example in 2004 57% of respondents felt that
"the scientists have shown in the long-term that their advice has been
justified".17 Most residents are relieved that the volcano is
monitored and MVO can initiate better warnings and there is better
acceptance of the need for forced evacuations. However, building the
required trust and a working co-operation between scientists, local
government and inhabitants has not been straightforward. There is now
considerable local awareness of the uncertainty inherent in the science
and appreciation that it helps avoid the unpopular decisions giving long,
and apparently unnecessary, evacuations before the new systems were in
place.18,19
The techniques we have developed have, to date, been mainly applied to
Montserrat. However, their use is now being extended to Latin America and
Papua New Guinea. We have run workshops to explain our techniques in Costa
Rica (October 2012), Ecuador and Colombia (June 2013). In these cases, the
impact on local inhabitants and commerce is yet to occur; however, the
existence and proven capabilities of the techniques developed by the Unit
are beginning to have an impact on local policy and planning in each case,
as knowledge of them and their potential application is spread.
Background information:
7. Clay. E., et al. (1999) An Evaluation of HMG's Response to the
Montserrat Volcanic Emergency. Evaluation Report EV635, December 1999.
DfID, 94 Victoria St, London SW1 5JL. http://www.dfid.gov.uk/Documents/publications1/evaluation/ev635.pdf.
8. http://bit.ly/17ANT3A(On the
invoking of International Charter for Space and Major Disasters)
9. NERC COMET report: http://comet.nerc.ac.uk/current_research_soufriere.html
10. Overseas countries and territories environmental profile, Part 2 -
Detailed Report, Section A - Caribbean region, (prepared by J.Pearse and
H. Berends) European Commission (EuropeAid Cooperation Office), 2007 http://bit.ly/1axtug7
11. Public Early Warning System (EWS) Case Studies: Volcanic Alerts http://bit.ly/18QhG1X
12. International Monetary Fund Country Report No. 12/9 United Kingdom:
Montserrat: British Overseas Territory, January 2012. http://www.imf.org/external/pubs/ft/scr/2012/cr1209.pdf
Sources to corroborate the impact
13. Assessment of the hazards and risks associated with the Soufriere Hills
volcano, Montserrat, 3rd Report of the Scientific Advisory
Committee on Montserrat Volcanic Activity, MVO, http://www.mvo.ms/resources/downloads/summary/45-sac-3/906-sac3technical
(also available from www.nerc-essc.ac.uk/~gw/www_data/SAC10-TR.doc).
14. Radar imaging of the volcano dome detailed in the monthly reports by the
Smithsonian Institution, National Museum of Natural History, Global
Volcanism Program, Soufrière Hills. http://bit.ly/HDj8yk
(search on "radar")
15. Charter final operation report, Charter ID 213, Volcanic eruption of 29th
July 2008 on the island of Montserrat, G. Ager et al., Report no:
CR/08/179. British Geological Survey (Keyworth) (Available upon request)
16. Journey to Sustainable Prosperity. Montserrat Sustainable Development
Plan 2008 - 2020, Ministry of Economic Development and Trade, Government
of Montserrat, 2010 http://www.gov.ms/publications/SDP_MONTSERRAT.pdf
(see table: Environmental and disaster management medium-term objective 4:
"Develop a comprehensive disaster management framework" and 3.4.4, 3.4.5
and 3.4.5 in particular)
17. Haynes, K., Barclay, J., & Pidgeon, N. (2008). Whose reality counts?
Factors affecting the perception of volcanic risk. J. Volcanol.
Geotherm. Res., 172(3), 259-272., doi:
10.1016/j.volgeores.2007.12.012.
18. Donovan, A.R. et al. (2013) Co-production of an institution: Montserrat
Volcano Observatory and social dependence on science. Science and
Public Policy, 40, 171-186, doi: 101093/scipol/scs078.
19. Donovan A.R. et al. (2012) Contested boundaries: Delineating the "safe
zone" on Montserrat, Applied Geography, 35, 508-514. doi:
10.1016/j.appgeog.2012.10.003.
20. Testimonial letter from the Director, Montserrat Volcano Observatory.
Available upon request.