Coastal inundation and the Floods Directive – A UNESCO- IOC perspective Presented by Russell Arthurton Coastal Geoscience, UK r.arthurton@talktalk.net Thank you to Maria and Mark for this opportunity to present the work of IOC UNESCO in respect of coastal inundation

IOC links with the WG-F reporting agenda Flood mapping (Article 6/ 3,4,6) (a) floods with a low probability, or extreme event scenarios (b) floods with a medium probability Risk assessment and mapping (Article 6/ 5) Probability and vulnerability assessments Flood Risk Management Plans (Article 7) Early warning systems Links with Civil Protection My presentation will cover issues where there is mutual interest in the work being carried out by this WG and by IOC on inundation by the sea. The issues include coastal flood hazard mapping, risk assessment and mapping including probability and vulnerability assessments, and the management of coastal flood risk through the development of early warning systems and strengthening the linkage between the science and Civil Protection. The country reporting formats and timelines turn out to be very relevant and timely to the objectives of IOC.

UNESCO-IOC global mandate for Tsunami Early Warning and Mitigation Systems ICG/NEAMTWS – NE Atlantic, Mediterranean and Connected Seas Technical Working Groups Hazard assessment and modelling Seismic and geophysics measurement Sea Level data collection and exchange Public awareness, preparedness and mitigation Task Teams System architecture Communication testing and tsunami exercises Multi-hazard approach to coastal inundation Following the Indian Ocean Tsunami of 2004, the IOC was given the mandate to extend the global coverage of tsunami early warning and mitigation systems from the Pacific Ocean to three other regions. The regional system of particular relevance to this WG (F) is NEAMTWS. I am here to represent the Intergovernmental Coordination Group for NEAM TWS. The Group is composed of representatives of IOC Member States, many of which are maritime MS of the European Union. The ICG has four Technical Working Groups. Two are focused on the real-time detection and messaging of potential hazard events though seismic and sea-level monitoring. The other two are concerned with hazard and risk assessment, and risk reduction, e.g. through preparedness. The ICG has created Task Teams to consider specific issues including the architecture of the TWS, Communication Testing and Exercises, and a Multi-Hazard approach – the latter of particular relevance to this WG (F)

ICG/NEAMTWS Task Team on a Multi-Hazard Approach to Coastal Inundation Main objectives: Identify relevant existing warning systems at national and European levels Explore the scope for linkages with such systems Assess the mutual value of interacting with various existing frameworks for coastal inundation mapping, in particular the EU Floods Directive One important activity of this Multi-Hazard Task Team is to assess the mutual value of interacting with various existing frameworks for coastal inundation mapping – in particular the EU Floods Directive.

Hazard Mapping (Article 6/ 3,4,6) Tsunamis Especially Mediterranean, Portugal and Black Sea countries Storm surges Especially northern European countries Joint probability of spring tides and river floods Extreme wind-forced waves Sea-level rise Long-term, climate change related Modelling physical parameters Probability – potential seismic/volcanic event locations and timings; meteo events; climate change Propagation – wave/surge patterns; travel times Inundation – country forecast points/zones; coastal shoaling effects; inundation limits and run-up; flow depths and velocities during inundation and drainage; debris considerations; existing protection The attention of the ICG/NEAMTWS to date has focused on tsunamis, but the IOC mandate includes all sea-level related flood hazards including storm surges, extreme wind-forced waves and long-term sea-level rise. Hazard assessment and mapping, supported by modelling, have been key areas of NEAMTWS work which may also be pertinent to WG. Modelling activities cover the probability of hazard events – their locations and timings; the propagation of waves and surges and e.g. the travel times of tsunamis to coastal forecast points. These times in the various Mediterranean sub-basins are short, generally less than 2 hours from source to an impacted coast. Modelling also covers the detail of coastal inundation, shoaling effects, inundation limits and run-up, flow depths and velocities during inundation and drainage. The resulting hazards maps are specific to likely tsunami and surge scenarios.

Risk Mapping (Article 6/ 5) Risk maps specific to each credible marine hazard scenario Assessment of dimensions of vulnerability people, buildings, economy, environment Change of vulnerability with time daytime/night variation, seasonal changes (especially tourism-related), long-term population changes; hazard changes, e.g. climate-change related, mitigation-related The preparation of Risk Maps is a key element of the TWS process. It is an activity about which IOC may have much to learn from this WG. Risk Maps are specific to a range of credible hazard scenarios. Difficulty in assessing what is a credible scenario, as the Japanese found out to their great cost last March. The vulnerability assessment that feeds into the Risk Maps for inundation from tsunamis must take account of the very short lead times for warning and possible evacuation. Also the variability of coastal populations – day/night, seasonal, and their ability to react effectively to a warning or evacuation order. The priorities that should be attached to the various dimensions of vulnerability to any of the inundation hazards can be difficult to determine.

Management Plans (Article 7/ 3) Early warning End-to-end system of warning to “the last mile” Hazard event detection and messaging (international /national) Communication tests and exercises SOPs for all parts of the warning system Civil Protection linkage Evacuation Planning Public Awareness Education Risk mitigation Structural, e.g. engineered protection Non-structural, e.g. land-use change/planning and regulation The core element of the NEAMTWS is the early warning system – an end-to-end system carrying warning messages to “the last mile”. However, the scope of all the IOC-coordinated TWSs is much broader. In addition to the development of the core warning capability, not only does it imply action at the national scale to assess hazard and risk, but it is also concerned with Risk Management activities relating to Civil Protection and Risk Mitigation. These activities correspond closely to the framework of the Management Plan, e.g. in the Types of Measures for use in the development of the schemas, as discussed yesterday in this meeting. Again, the NEAM ICG welcomes cooperation with this WG on these aspects of managing the risk of coastal inundation in a multi-hazard context.

Management Plans (Article 7/ 3) ICG/NEAMTWS Working Group 4 Public Awareness, Preparedness and Mitigation Reducing and Managing the Risk of Tsunamis With Civil Protection in mind, the ICG’s WG4 has produced a guidance document explaining all aspects of the NEAMTWS, from tsunami hazard, vulnerability and risk assessment and mapping, through the functioning of the core warning system, to preparedness, awareness and mitigation. This document is being put to the ICG for approval at their meeting in Spain next month. That closes my presentation. Thank you. Guidance for National Civil Protection Agencies and Disaster Management Offices as Part of the Tsunami Early Warning and Mitigation System in the North-eastern Atlantic, the Mediterranean and Connected Seas Region – NEAMTWS