Extreme Geohazards

72 Pages·2015·7.94 MB·English

Extreme Geohazards:
Reducing the Disaster Risk
and Increasing Resilience
A Community Science Position Paper
European Science Foundation (ESF) Authors
The European Science Foundation was established • H ans-Peter Plag
in 1974 to provide a common platform for its Member Climate Change and Sea Level Rise Initiative,
Organisations – the main research funding and Old Dominion University, Norfolk, VA, USA
research performing organisations in Europe – to • S ean Brocklebank
advance European research collaboration and School of Economics, University of Edinburgh, UK
explore new directions for research. ESF provides • D eborah Brosnan
valuable services to the scientific and academic One Health Institute, University of California Davis,
communities – such as peer review, evaluation, Davis, CA, USA
career tracking, conferences, implementation of new
• P aola Campus
research support mechanisms and the hosting of
European Science Foundation, Strasbourg, France
high-level expert boards and committees – with the
aim of supporting and driving the future of a globally • S ierd Cloetingh
Department of Earth Sciences, Utrecht University,
competitive European Research Area. ESF currently
The Netherlands
has 66 member organisations in 29 countries.
• Shelley Jules-Plag
www.esf.org
Tiwah UG, Rossbach, Germany
• S eth Stein
Department of Earth and Planetary Sciences,
Group on Earth Observations (GEO)
Northwestern University, Evanston, IL, USA
The Group on Earth Observations (GEO) is an
intergovernmental organisation developing and
implementing the Global Earth Observation System
of Systems (GEOSS). GEO’s vision is a future wherein
This document considers the disaster risk
decisions and actions, for the benefit of humankind,
associated with extreme geohazards and
are informed by coordinated, comprehensive and
addresses the challenges of disaster risk
sustained Earth observation and information. GEO
reduction for these low-probability, high-
has currently 97 Member Countries and is supported
impact events. The paper was supported by
by 80 Participating Organisations.
the European Science Foundation (ESF). It was
www.earthobservations.org initiated at the high-level ESF-COST conference on
‘Understanding Extreme Geohazards: The Science
of the Disaster Risk Management Cycle’ held in
Geohazard Community of Practice (GHCP) November 2011 in Spain (see www.geohazcop.
org/workshops/Sant_Feliu_2011). The Declaration
The GHCP is a Community of Practice (CoP)
on Extreme Geohazards and the Reduction
supporting the Group on Earth Observations (GEO).
of Disaster Risks, which resulted from this
The GHCP brings together groups and individuals
conference is reproduced in Appendix C.
involved in various aspects of geohazards, including
research, monitoring and risk assessments,
mitigation, and adaptation. The GHCP aims to
provide a link between the broad geohazards
community of practice and GEO in order to ensure
that the needs of this community are taken into
account in the development of GEOSS; to facilitate
support and participation of this community in the
building of GEOSS; and promote the use of GEOSS
for geohazards-related applications. The GHCP
also provides a communication and coordinating
platform for high level policy makers and the broader
geohazards community.
www.geohazcop.org
Cover picture:
Bárdabunga volcano, Iceland, 13 September 2014.
© iStock
ISBN: 978-2-36873-197-0
Contents
Forewords 3
Summary of Key Findings 6
Executive Summary 7
Abstract 11
1. Introduction 13
2. Global Disasters and Catastrophes 15
3. Extreme Geohazards 19
3.1 Knowing the Upper End of the Hazard Spectrum 19
3.2 Impacts of Extreme Geohazards and Associated Risks 20
3.3 Earthquakes and Tsunamis 22
3.4 Extreme Weather and Landslides 24
3.5 Bolides 24
3.6 Volcanoes 24
3.7 Comparison of Geohazards and Other Natural Hazards 30
4. Disaster Risk, Resilience, Antifragility and Adaptive Capacity 33
5. Cost–Benefit Analysis of Planning for Extreme Geohazards 37
6. Confronting Disaster Risks for Extreme Geohazards 40
6.1 Governance for Extreme Geohazards 40
6.2 Knowledge Assessments and Research Needs 42
6.3 Monitoring and Early Warning 44
7. Conclusions and Recommendations 48
Acknowledgements 51
Acronyms and Abbreviations 51
References 52
Appendices 59
• Appendix A: Glossary 61
• Appendix B: Overview of Earthquakes in the Last 2,000 Years 62
• Appendix C: Declaration on Extreme Geohazards and the Reduction of Disaster Risks 66

Foreword
In his third letter on sunspots (December, 1612) More timely dissemination and use of geospatial
to Mark Wesler, Galileo Galilei writes “the mod- information from globally coordinated systems to
ern observations deprive all former writers of any monitor, predict, assess risk, provide early warn-
authority, since if they had seen what we see, they ing, and mitigate and respond to hazards will help
would have judged as we judge”. reduce loss of life and property at the local, national
Four hundred years have passed since this letter and regional level. The disaster risk reduction and
was written, but today, more than ever, it is vital management challenges facing the global commu-
to continue to observe the Earth and invest our nity increasingly demand broad and timely access to
resources and capabilities in the development of new high-quality, integrated and sustained Earth obser-
observation systems and tools capable of analysing vation data and related information.
these data and providing new information. Moreover, Earth observations are owned by 3
The Earth is a complex, dynamic system we many entities around the world, and no single
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do not yet fully understand. Our existence on the country is able to acquire the comprehensive data n
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planet and our vulnerability to natural hazards is and tools it needs to inform policy in these critical sili
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controlled by complex mechanisms that are often domains. Specifically, crisis management resulting g R
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unstable and difficult to interpret. Observing these from high-frequency natural and human-induced si
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mechanisms and their interactions, to allow recon- extreme events requires capacities that generally re
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struction of the past and prediction of the Earth’s cannot be provided by one country alone; effective d In
future behaviour, should be a priority for every gov- response requires regional/international collabora- an
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ernment. tion and coordination so that, when such events s
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Earth observations (EO) and information occur, the flow of data from various countries, as r
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– derived from space, airborne, land and marine net- well as the international organisations in which they as
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works – play an essential role in helping to increase are represented, works smoothly. This is particularly Di
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the resilience of societies to natural hazards. The true in the case of extreme hazards, where the poten- t
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facility to provide decision makers with critical and tial effect of an event could have a regional or global n
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factual data is needed to drive investments to reduce impact with dramatic consequences on society. d
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underlying disaster risk factors and to make soci- The treatise contained in this Science Position s: R
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ety more adaptable to the effects of climate change. Paper raises serious questions about how the current r
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By using Earth observation data and information, and future global population can be better prepared a
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societies can enhance the resilience of exposed com- for extreme geohazard events and their potentially e
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munities to hazards and, more importantly, can calamitous impacts. As this important discussion me
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improve the response of individuals, urban systems moves forward, leaders in government, the private tr
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and related infrastructures to extreme events. sector, civil society, and members of the general E
The Group on Earth Observations (GEO) is public should take into account the essential con-
working to expand the use of satellite imagery and tribution of Earth observations to these issues and
surface data to support governments that are devel- to their eventual outcomes.
oping sustainable development policies and reducing
exposure and vulnerability to disaster risks posed
by natural and human-induced hazards. The GEO Barbara J. Ryan
community is developing decision-support tools and Secretariat Director,
applications for the full cycle of disaster manage- Group on Earth Observations (GEO)
ment, particularly for developing countries, working
in close collaboration with national space agencies
through the Committee on Earth Observation
Satellites (CEOS) – the space coordination arm of
GEO – to help improve all phases of disaster risk
management (DRM) on a global basis.
Foreword
Natural hazards that occur frequently on our Conference 2012, European Geosciences Union
dynamic planet are increasingly causing loss 2013, European Geosciences Union 2014, Global
of human life and damage to goods and infra- Risk Forum 2014, GEORISK 2014) the Science
structures at the local, regional and global scale, Position Paper has gained the attention and input
depending on their intensity. The Science Position of other scientific experts, thus further expanding
Paper Extreme Geohazards: Reducing the Disaster its content and taking the paper well beyond its
Risk and Increasing Resilience analyses the poten- originally planned Executive Summary format.
tial effects of low-probability high-impact events, The Science Position Paper addresses several
which might cause global disasters and even bring types of geohazards, but puts special emphasis on
our already stressed global society beyond the limits the mounting risk of catastrophic effects on popu-
4 of sustainability. lations and infrastructures should our growing
The initiative that led to the preparation of this and increasingly interconnected modern society
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n Science Position Paper originated from the high- be exposed to a very large volcanic eruption. The
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sili level research conference ‘Understanding Extreme paper highlights the urgency of establishing an
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g R Geohazards: The Science of the Disaster Risk effective dialogue with international organisations
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si Management Cycle’ (Sant Feliu de Guixols, Spain, and policy makers in order to develop robust risk
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re 27 November–2 December 2011), which was co- management, disaster risk reduction, resilience,
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d In sponsored by the European Science Foundation and sustainability plans in the coming years and
an and COST. decades. It also underlines the need to develop
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s The conference gathered a variety of experts, the methodology to assess the potentially global
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r including representatives of international organi- impacts that a major hazard would have on our
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as sations such as the United Nations Educational, modern society, which would provide guidance to
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Di Scientific and Cultural Organization (UNESCO), reduce vulnerability where possible and increase
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t the Integrated Research on Disaster Risk general resilience in the face of surprise events. It
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n (IRDR), the International Union of Geodesy and concludes that preparedness requires a global mon-
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d Geophysics (IUGG), the United Nations Office itoring system that could provide timely warning
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s: R for Project Services (UNOPS), the United Nations should such a major hazardous event develop.
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r Development Programme (UNDP), the Group
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a on Earth Observations (GEO), and the Global
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e Earthquake Model (GEM) Foundation. The experts Professor Dr Hans-Peter Plag
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me reviewed the understanding of extreme geohaz- Professor, Ocean, Earth and Atmospheric Sciences,
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tr ards and the how, why, and when of these events. Director, Mitigation and Adaptation Research
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E Examples and forensic analyses were presented for Institute (MARI) Old Dominion University,
a number of disasters that have occurred in the last Norfolk, Va, USA
decades and caused huge loss of human life and cat-
astrophic damage in different regions of the planet. Dr Paola Campus
In the course of the discussions the experts con- European Science Foundation (ESF),
curred on the idea of documenting the main existing Senior Science Officer in charge of the Scientific
issues and needs for the future, and identified the Review Group for Life, Earth and Environmental
Life, Earth and Environmental Sciences (LESC) Unit, Sciences
working under the auspices of the LESC Standing
Committee (now the Scientific Review Group for Professor Dr Reinhart Ceulemans
Life, Earth and Environmental Sciences, SRG-LEE) Chair of the ESF Scientific Review Group for Life,
as the ideal platform to promote this action. Earth and Environmental Sciences, SRG-LEE
In the course of its preparation and thanks to
extensive dissemination at specialised international
conferences and meetings (AGU Science Policy
I am very pleased that ESF has been able to sup-
port the initiating Conference and the subsequent
work of the research communities concerned. The
Position Paper is very timely and addresses key
issues of hazards, resilience and sustainability
through the contributions from a range of experts.
I note that Director Ryan introduces her
Foreword with a reference to Galileo Galilei’s writ-
ing on sunspots and related observations. At our
current state of development, space and geohazards
can heavily jeopardise large communities, commu- 5
nications and resilience. For this reason, our society
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needs a comprehensive and enhanced monitoring n
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network with associated rapid response system. sili
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The social elements of the challenges involved g R
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with Planet Earth have been well outlined in earlier si
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ESF reports, notably in the ESF-COST publication re
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RESCUE: Responses to Environmental and Societal d I
Challenges for our Unstable Earth. an
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This Science Position Paper is not only aligned s
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with the message of RESCUE, but it further r
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elaborates concepts related to the Sustainable Devel- as
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opment Goals endorsed at the Rio+20 – United Di
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Nations Conference on Sustainable Development. t
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I have no doubt that this Paper will be of interest n
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to a large number of stakeholders and will generate d
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opportunities for improved collaboration as well as s: R
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concerted actions in the future. r
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Martin Hynes me
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ESF Chief Executive tr
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Summary of Key Findings
• Extreme geohazards have the potential to gener- processes and strengthen resilience through
ate global disasters. increased social capital.
• Recent large earthquakes have illustrated the • An international process is needed to assess
extent of the destruction that extreme geohaz- repeatedly the global risk associated with
ards can inflict on a modern society, particularly extreme hazards, including geohazards, and our
through cascading effects and chains of failure. preparedness to cope with these high-impact
• Disaster risk reduction (DRR) focuses on the events.
risk associated with relatively frequent hazards • This process could be an amalgam of the process
with major impacts, while the risk associated used by the Intergovernmental Panel on Climate
with low-probability, high-impact events is not Change, the Quaternary Defense Review carried
6 sufficiently considered. out by the Department of Defense of the USA,
• Threats from low-frequency, high-impact events and the Global Risk assessment carried out by
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n are grossly underestimated in DRR. the World Economic Forum.
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sili • This is particularly true for volcanic eruptions. • A model-based global simulation of one or more
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g R So far, modern civilisation has not been exposed extreme volcanic eruptions that took place dur-
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si to an eruption comparable to the most extreme ing the Holocene would provide a basis for a
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re events that occurred during the Holocene. realistic assessment of the risk and the identifi-
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d In • Under today’s circumstances, these events are cation of potential cascading effects and chains
an associated with extreme disaster risks, com- of failure.
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s parable to other possible mega-disasters from • The International Charter on Space and Major
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r extreme droughts, floods, pandemics and aster- Disasters should be extended to cover cases of
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as oid impacts. emerging threats for early warning purposes
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Di • A global volcano-monitoring system is required prior to the occurrence of a disaster.
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t as a basis for an early warning system to provide
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d tation and food security.
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r basis several billion dollars per year should be
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a invested to significantly reduce the risk associ-
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e ated with extreme volcanic eruptions.
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me • Efficient DRR will also require a reduction in
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tr the vulnerability of infrastructure, an increase
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E of general economic and social resilience, and the
development of capabilities to adapt to poten-
tially large long-term changes in environmental
conditions.
• A paradigm shift toward integrated DRR and
Resilience (D3R) programmes could more
aggressively facilitate the public trust, coopera-
tion, and communication needed to adequately
prepare for and recover from expected disasters
as well as ‘ Black Swan’ disasters (low-probability,
high-consequence events that are difficult to pre-
dict or prevent).
• In D3R, science does not have the primary goal
of reducing uncertainties and prediction errors
for hazards, but rather to develop antifragile
Executive Summary
Extreme Hazards: Potential upper end of the hazard spectrum. The increasing
Causes of Global Disasters and complexity of societies allows even moderate haz-
Catastrophes ardous events to cause regional and global disasters.
Understanding the disaster risk therefore requires
Humanity is exposed to a broad ensemble of natural a distinction to be made between the event (the
and anthropogenic hazards that could cause global occurrence of a hazard) and the processes that are
disasters and catastrophes. Efforts in disaster risk triggered by this event and determine its conse-
reduction are challenged by the nature of such quences.
extreme events: they are rare, occur as surprises,
and tend to have high impacts. Because they are
rare, the serious threat posed by extreme events Global Disasters and Catastrophes 7
tends to be underrated. The increasingly complex
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built environment and global dependencies can lead Risk assessments for extreme hazards require an n
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to domino effects amplifying the direct impacts of understanding of the processes triggered in the sili
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the hazards. Global catastrophes caused by extreme complex coupled human–natural system by the g R
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natural hazards have the potential to severely events that lead, or do not lead, to X-events that are si
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impact the global economy, food security and sta- rare, surprising, and have potentially huge impact re
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bility. Floods and droughts are major threats that on human life. These X-events are outliers outside d In
potentially could reach a planetary extent through of the ‘normal’ region that could lead to ‘the collapse an
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secondary economic and social impacts. With of everything’. Increasingly, the complexity of mod- s
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megacities and crucial industries situated in areas ern life amplifies the impacts of natural hazards. r
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exposed to natural hazards, earthquakes, tsunamis, Although we understand the ‘how’ and ‘why’ for as
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and volcanic eruptions might cause disasters that most natural hazards events (although not necessar- Di
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could exceed the capacity of the global economy ily the ‘when’), how such hazards lead to X-events is t
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to cope. Addressing the challenges that these rare, less well-studied and understood. For many natural n
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high-impact events pose to human life and prop- hazards, the unfolding time is short, but the impact d
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erty is essential for the long-term sustainability of time can be much longer. Events that have a short s: R
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civilisation. unfolding time but large total impacts over very r
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Given the nature of these extreme hazards, most long impact times are those that are surprising and a
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ideas about them are based on indirect evidence; difficult to prepare for. Extreme geohazards fall into e
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in particular the impacts of the hazards on the this class of event. me
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environment and on society are difficult to assess tr
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with certainty. Risk as conventionally defined – E
the product of hazard probability, value of assets Extreme Geohazards
exposed to the hazard, and the vulnerability of the
assets – is hard to assess. When the hazard prob- Geohazards such as earthquakes, landslides,
ability is very low, we lack the knowledge to reliably volcanic eruptions, tsunamis and floods cause
estimate vulnerabilities, especially from indirect significant loss of life and property. Most of these
effects, both in the near and far-field of the haz- losses occur during high-impact events and these
ardous event. losses are increasing as the number of people who
While the probabilities of most natural hazards live in areas exposed to such hazards continues to
do not change much over time, the sensitivity of rise. Recent major geohazards are dwarfed by the
the built environment and the embedded socio-eco- largest geohazards that occurred several times dur-
nomic fabric has changed. Exposure to geohazards ing the Holocene. If such a mega hazard were to
has increased dramatically in recent decades and occur today, the resulting disaster impacts would
continues to do so. Most of the increasing losses be unparalleled. To increase global resilience and
occur during less frequent high-impact events at the reduce the disasters induced by the occurrence of
extreme hazards at an acceptable economic cost During the Holocene, at least seven VEI 7
requires a solid scientific understanding of the eruptions took place [VEI: Volcanic Explosivity
impacts these hazards could have on modern society. Index]. All but one occurred at a time when the
Th e extreme earthquakes that occurred during global population was far below 1 billion; with a
the last 2000 years have illustrated the destruc- population above 7 billion and heading for 12 bil-
tion they can infl ict (Figure 8), both directly and, lion, a recurrence of a VEI 7 eruption could have
through tsunamis, indirectly. Th e resulting dis- extreme consequences. The probability of such
asters are amplifi ed in areas with poor building an event occurring in the 21st century is 5–10%.
infrastructure. As a consequence, the earthquakes Consequently, VEI 7 and larger eruptions represent
with the largest magnitude are not necessarily those a severe threat for our modern society.
that turn out to cause the most fatalities or greatest
damage. In general, poor countries that are exposed
to the same level of hazards as more developed Disaster Risk, Resilience,
countries experience a disproportionate number Antifragility and Adaptive Capacity
of disasters.
Th e volcanic eruptions in the last few decades With the prospect of the global population reach-
have oft en resulted in a high ratio of fatalities to ing 12 billion by 2100, humanity faces the crucial
the immediately impacted population. All but one challenge of developing in a very limited time an
8 of these eruptions were relatively minor and direct eff ective programme to reduce the risk of global dis-
impacts were local. For larger volcanic eruptions, asters and catastrophes caused by natural hazards.
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n volcanic ash and gases can induce large indirect Considering risk as the product of hazard probabil-
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sili eff ects that oft en exceed the direct impacts in the ity, sensitivity to the hazard, and the value of the
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g R near-fi eld of the volcano. Th is is illustrated by a exposed assets, it is obvious that risk mainly can
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si number of eruptions that have taken place in the be reduced by reducing sensitivity and exposure.
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re last few hundred years (Figure 12). Adaptation and mitigation eff orts to reduce sensi-
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d In Extreme geohazards that occurred throughout tivity and exposure represent insurance against the
an the last few thousand years rarely caused major dis- risk. Willingness to engage in adaptation and miti-
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s asters because the population density was low, the gation depends on risk perception. Th e challenge of
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r built environment was not sprawling into hazardous extreme geohazards is that they are infrequent and
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as areas to the same extent as today, and human soci- risk awareness is generally low. Th erefore, the costs
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Di eties were much less complex than today. Similar for adaptation and mitigation are oft en postponed.
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t extreme events today could cause unparalleled dam- Extreme geohazards have short unfolding
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n age on a global scale and worsen the sustainability times, leaving little room to increase preparedness
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d crisis. Simulation of these extreme hazards under when an event has started to unfold. Despite the
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s: R present conditions can help to assess the disaster low probability of such extreme events, their risk
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r risk and underline the fact that we have been lucky is increasing due to the increasing complexity of
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a during the last century. our civilisation. Eff orts to be better prepared for
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e Large volcanic eruptions have the potential to extreme events by developing general resilience are
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me impact climate, anthropogenic infrastructure and urgently needed, and an immediate benefi t would
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tr resource supplies on global scale. Under the pre- be increased preparedness for frequent events that
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E sent conditions of a globally connected civilisation cause an increasing number of fatalities and rapidly
facing food, water and energy scarcity, the largest escalating damage. General preparedness needs to
eruptions during the Holocene would have had be developed as part of the design of communities.
major global consequences. Events on the scale of For hazards with a potentially global extent, the
the Toba eruption 74,000 years ago could return provision of ‘lifeboats’ should be the aim for our
humanity to a pre-civilisation state. Volcanic global civilisation, just as a ship should have suf-
eruptions can have more severe impacts through fi cient lifeboats for the passengers in the event of
atmospheric and climate eff ects and can lead to an emergency. A focus on food and water reserves,
drastic problems in food and water security, as technology redundancy, and social community
emphasised by the widespread famine and diseases resilience is therefore a prerequisite for any success-
that were rampant aft er the Laki 1783 and Tambora ful global disaster risk reduction strategy.
1815 eruptions. Hence extreme volcanic eruptions For a better understanding of how human inter-
pose a higher associated risk than all other natural actions with extreme hazardous events can increase,
hazards with similar recurrence periods, including or reduce, the impacts, information on the processes
asteroid impacts. that unfold during and aft er the incidents is needed.