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2. 2 Extreme Geohazards Reducing Disasters Risk and Increasing Resilience Hans-Peter Plag, Mitigation and Adaptation Research Institute, Old Dominion University, Norfolk, VA, USA Supported by: Geohazards Community of Practice of the Group on Earth Observations (GEO) European Science Foundation (ESF)

3. 3 The problem: - extreme hazards occurred in the past; little exposure often limited the disaster - increased exposure leads to more frequent disasters - complexity of modern societies leads to more indirect, cascading effects - sustainability crisis reduces resilience Increasing disaster risk due to: - more exposure of a growing population; - reduced resilience due to interconnection, reduced redundancy, and dependence on just-in-time services - direct and indirect impacts (domino-effects) increase risk of a global catastrophe caused by extreme natural hazards. Why Focus on Extreme (Geo)Hazards? Extreme Geohazards: - landslides - tsunamis - earthquakes - volcanic eruptions

4. 4 Origin of the White Paper Declaration on Extreme Geohazards and the Reduction of Disaster Risks Resulted in two main activities: - White Paper on Extreme Geohazards - Global Geohazards Information System for Disaster Risk Reduction (GGIS-DRR) 1 Introduction2 Extreme Hazards and Global Disasters and Catastrophes3 What are extreme geohazards?4 How well do we know the upper end of the hazard spectrum?5 What are the Impacts of Extreme Geohazards? Earthquakes Volcanoes Comparison of geohazards and other natural hazards 6 Disaster Risk, Resilience, Antifragility, and Adaptive Capacity7 What are the Major Vulnerabilities and Risks?8 How can we Reduce Vulnerability and Risks?9 How can we Deal with the Uncertainties?10 Cost/Benefit Analysis of Planning for Extreme Geohazards11 How Should Society Confront Impacts of Extreme Geohazards?12 Societal and Governance Processes for Disaster Risk Reduction13 What is the Role of Science in Reducing Impacts of Extreme Geohazards? Research needs Monitoring and early warning What are the Consequences of the Current Scientific Dialog? 14 Conclusions Acronyms References

5. 5 Extreme Events: Extinction Level Events: more than a quarter of all life on Earth is killed and major species extinction takes place. Global Catastrophes: more than a quarter of the world human population dies and that place civilization in serious risk. Global Disasters: global-scale events in which a few percent of the population die. Major Disasters: disasters exceeding $100 Billion in damage and/or causing more than 10,000 fatalities. Modified from Hempsell (2004) Terminology

6. 6 Measuring Impacts TsunamiEarthquake CycloneEarthquake

7. 7 The problems: - knowledge of rare events is limited - know better the “why” and “how” but not the “when” - probability is difficult to assess Extreme (Geo)Hazards - risk assessment is challenged Poisson distribution; Chance that one or more “1 in N years” events occur in a century: In the 20 th century we have been lucky...

8. Earthquakes

11. Volcanic Eruptions

12. 1) Krakatau was similar to Santorini eruption, 1600 BC, although 4 times smaller Eyafjallajokull, 2010: VEI 4, 0.25 km 3 Laki 1783-85: VEI 6, 14 km 3 Several eruptions that happened during the last 2,000 years would be devastating under todays conditions 100,000 40,000 30,000 25,000 15,000 10,000 5,000 4,000 3,500 3,400

13. Extreme Hazards

14. 14 Toba, ~75,000 years ago, VEI 8, 2,800 km 3 ; killed up to 60% of human population Cost-Benefit Analysis Impacts: - ash layer, several million square kilometers - destroying one or two seasons of crops for two billion people - reducing global temperature by 5-15 o C - substantial physical damage to infrastructure Death comparable to other global disasters: - 1918 Spanish flu: 3% - 5% of global population We assume: - 10% of global population is killed if volcano eruption comes as a surprise

15. 15 - Value of statistical life (VSL): $9.1 million (U.S. Department of Transportation) - U.S. citizen should be willing to spend $910 to eliminate a 1 in 10,000 risk of fatality - Global VSL: $2.22 million - Average person should be willing to pay $2.22 per year to eliminate the risk. Toba-type eruption: 1 in 100,000 years; fatalities 10%: Probability of a random person dying in any particular year: 1 in 1,000,000. Global population over 7 billion: $15 billion per year. 2014 USGS Budget: $24.7 million for volcano monitoring Same level globally: $370 million Benefit to Cost ratio > 20! Eliminating half of the risk is worth $7.5 billion per year. Cost-Benefit Analysis Total cost of disaster risk plus mitigation of risk mitigation level n n* C(n)C(n) Details will not change the main conclusion: - Spending on the order of $1 Billion/year on risk reduction for major volcanic eruptions makes economically sense based on standard cost-benefit analysis - Would have many positive side effects not considered

16. 16 The largest volcano eruptions of the millennia (1 in 500 to 1000 years events): - today would threaten an already stressed food supply - challenge the crucial global transportation network - could easily lead to a global catastrophe. Conclusion Steps towards risk reduction and increased resilience: (1) Risk assessment and risk awareness: - Frequent review of global risk knowledge with IPCC-like process (3) Response to Early Warning: - dedicate research to understand societal response to EWs on time scales of years - - also important for EWs of abrupt climate change impacts Chance of a major eruption (order VEI 7, 100 km 3 ) in the 21st century: 10-20%: - severe implications for food security, public health, transportation, global economy. (2) Early Warning (EW): - core element: elaborate, comprehensive volcano observing system; - cost-benefit analysis: should be willing to spend > $500 M/year; - GEO’s Geohazards Community of Practice is reviewing observation requirements

17. 17 CEOS acknowledges the need to look into volcano monitoring... Road Map GHCP - coordinates with/involves IUGG, IAVCEI, EPOS, ESF,... - produces a report and presents this to CEOS User needs assessment: - who would need what information when? - what information is available with what delay and spatial coverage? - what are the gaps? - how could the gaps be closed? CEOS coordinates with/asks GHCP to lead a user needs assessment: