IOTWS Operations and Limitations

This document provides a description of the real-time monitoring and alerting activities of the Indian Ocean Tsunami Warning and Mitigation System (IOTWS), considered in the context of the other actions which are required for effective warning and mitigation of tsunamis. These other activities, such as emergency response, planning, education and risk assessment are generally the responsibility of national and local authorities, and will be most effective when carried out with awareness of the capabilities and limitations of the international tsunami service providers. The Regional Tsunami Service Providers (RTSPs) of the IOTWS have been fully operational since 31 March 2013, but have been developing and testing their capabilities since 2009. They now provide an advanced tsunami forecasting service based on earthquake detection, sea-level measurements and oceanographic modeling, which includes detailed threat information for almost 800 coastal zones around the Indian Ocean. The three centres currently acting as RTSPs each cover the whole area of responsibility of the Indian Ocean and have aligned their coastal forecast zones, accuracy and timeliness targets, and output product formats to ensure that National Tsunami Warning Centres (NTWCs) can readily use the forecasts from any or all of the RTSPs. The tsunami models used by the RTSPs are similar but differ in their detailed configurations. This leads to some differences, generally small, in the forecasts produced by the centres, so it is important that NTWCs understand the basis for the forecasts and the significance of any differences. The RTSP products include tsunami arrival and cessation times and maximum wave amplitudes for all threatened coastal zones, and so can be rather complex. Some of the issues involved in interpreting the products are discussed here, including the potential to use modeled tsunami forecasts to improve risk assessment for local areas. Although the real-time operation of the IOTWS is working well, there are several limitations and areas of potential improvement, most of which are currently being addressed. Several of the current limitations are discussed here.</p

Tsunami wave height forecasting at coastlines with complex geometries : an integrated approach for the analysis of results from early warning systems and inundation modelling for risk assessment

A Tsunami Warning System must alert all persons on every vulnerable coast of imminent danger, covered by the system. The response of such a system must be rapid (as soon as possible), accurate (minimize false warning), reliable (continuous operation), effective (to save lives). UN-ISDR Framework for effective Early Warning Systems encompass four critical linked elements;1. Detection, Monitoring and Warning Service (Technical Monitoring and Warning Service)2. Risk Knowledge (Awareness of the Risk)3. Dissemination and Communication (Dissemination of meaningful warnings to Persons and Communities at Risk)4. Response Capability (Public Awareness and Preparedness to Respond)Project funded by the UNESCAP-TRATE (IOTWS) Proje

Risk assessment and mitigation within a Tsunami forecasting and early warning framework : case study Port City of Galle

The primary objective of this report is to present the results of a case study on tsunami risk assessment and management for a coastal city, on this occasion for the port city of Galle in the southern province of Sri Lanka. Preliminary studies were implemented by Hettiarachchi et.al (2009). Thereafter detailed studies were undertaken at regular intervals on a number of critical areas to examine post tsunami rehabilitation and risk assessment and management which is presented in this report. The report is presented in a manner that it provides the important steps relating to tsunami risk assessment and management in the generic context and thereafter at the end of each chapter the outcome of the applications to the port city of Galle is presented in text boxes. Components of risk and its assessment, assessment of impacts of hazards, vulnerability, community resilience, risk and risk management methods are discussed in detail in Chapters 2 to 7. A total of eleven text boxes are presented on the applications to the port city of Galle. Of specific importance is Chapter 8 on Tsunami Risk Assessment within a Tsunami Forecasting and Early Warning Framework, whereby an integrated approach for the analysis of results from early warning systems and inundation modelling for risk assessment is presented for improved tsunami wave height forecasting on the shoreline. This identifies the need to refine the tsunami wave forecasting provided by the Regional Tsunami Service Providers (RTSPs) for cities having complex geometrical shoreline features and bathymetrical features. The basic concept of this approach is presented in Chapter 8 whereas a dedicated case study on improved tsunami wave height forecasting is presented as a separate report (refer Chapter 8 for details). If this case study was included in the main text it would have caused an imbalance in the report due to the very technical nature of the subject matter covered. Here again, the case study is presented initially in the generic form followed by the application to the port city of Galle. Chapter 9 is dedicated to Resilient Cities, focusing on the UN-ISDR initiative which is fully supported by the Working Group on Risk Assessment and Reduction of the IOTWS.Project funded by the UNESCAP-TRATE (IOTWS) Proje

SDG14: life below water : navigating life below water in Asia and the Pacific

The 2030 Agenda and its Sustainable Development Goals provide a blueprint to achieve a better and more sustainable future for all. The Agenda addresses global challenges including those related to poverty, inequality, climate, environmental degradation, prosperity, and peace and justice. Goal 14, Life below Water, seeks to conserve and sustainably use the oceans, seas and marine resources for sustainable development. How are the ambitions of Goal 14 water going? Since its adoption in 2015, is the world on track to meet the ambitions of Goal 14? What are the challenges in measuring change? What are the current data and information challenges? This paper aims to provide an overview of progress made on data availability and reporting for Goal 14 in Asia and the Pacific, the home of the Indian and Pacific Oceans, illustrating challenges and new opportunities

Supplemental Information 4: Raw data.

This study evaluated pollution levels in water and sediments of Península de Paraguaná and related these levels with benthic macrofauna along a coastal area where the largest Venezuelan oil refineries have operated over the past 60 years. For this, the concentration of heavy metals, of hydrocarbon compounds and the community structure of the macrobenthos were examined at 20 sites distributed along 40 km of coastline for six consecutive years, which included windy and calm seasons. The spatial variability of organic and inorganic compounds showed considerably high coastal pollution along the study area, across both years and seasons. The southern sites, closest to the refineries, had consistently higher concentrations of heavy metals and organic compounds in water and sediments when compared to those in the north. The benthic community was dominated by polychaetes at all sites, seasons and years, and their abundance and distribution were significantly correlated with physical and chemical characteristics of the sediments. Sites close to the oil refineries were consistently dominated by families known to tolerate xenobiotics, such as Capitellidae and Spionidae. The results from this study highlight the importance of continuing long-term environmental monitoring programs to assess the impact of effluent discharge and spill events from the oil refineries that operate in the western coast of Paraguaná, Venezuela

Assessment of coastal management options by means of multilayered ecosystem models

This paper presents a multilayered ecosystem modelling approach that combines the simulation of the biogeochemistry of a coastal ecosystem with the simulation of the main forcing functions, such as catchment loading and aquaculture activities. This approach was developed as a tool for sustainable management of coastal ecosystems. A key feature is to simulate management scenarios that account for changes in multiple uses and enable assessment of cumulative impacts of coastal activities. The model was applied to a coastal zone in China with large aquaculture production and multiple catchment uses, and where management efforts to improve water quality are under way. Development scenarios designed in conjunction with local managers and aquaculture producers include the reduction of fish cages and treatment of wastewater. Despite the reduction in nutrient loading simulated in three different scenarios, inorganic nutrient concentrations in the bay were predicted to exceed the thresholds for poor quality defined by Chinese seawater quality legislation. For all scenarios there is still a Moderate High to High nutrient loading from the catchment, so further reductions might be enacted, together with additional decreases in fish cage culture. The model predicts that overall, shellfish production decreases by 10%–28% using any of these development scenarios, principally because shellfish growth is being sustained by the substances to be reduced for improvement of water quality. The model outcomes indicate that this may be counteracted by zoning of shellfish aquaculture at the ecosystem level in order to optimize trade-offs between productivity and environmental effects. The present case study exemplifies the value of multilayered ecosystem modelling as a tool for Integrated Coastal Zone Management and for the adoption of ecosystem approaches for marine resource management. This modelling approach can be applied worldwide, and may be particularly useful for the application of coastal management regulation, for instance in the implementation of the European Marine Strategy Framework Directive

Essential ocean variables for global sustained observations of biodiversity and ecosystem changes

International audience; Sustained observations of marine biodiversity and ecosystems focused on specific conservation and management problems are needed around the world to effectively mitigate or manage changes resulting from anthropogenic pressures. These observations, while complex and expensive, are required by the international scientific, governance and policy communities to provide baselines against which the effects of human pressures and climate change may be measured and reported, and resources allocated to implement solutions. To identify biological and ecological essential ocean variables (EOVs) for implementation within a global ocean observing system that is relevant for science, informs society, and technologically feasible, we used a driver-pressure-state-impact-response (DPSIR) model. We (1) examined relevant international agreements to identify societal drivers and pressures on marine resources and ecosystems, (2) evaluated the temporal and spatial scales of variables measured by 100+ observing programs, and (3) analysed the impact and scalability of these variables and how they contribute to address societal and scientific issues. EOVs were related to the status of ecosystem components (phytoplankton and zoo-plankton biomass and diversity, and abundance and distribution of fish, marine turtles, birds and mammals), and to the extent and health of ecosystems (cover and composition of hard coral, seagrass, mangrove and macroalgal canopy). Benthic invertebrate abundance and distribution and microbe diversity and biomass were identified as emerging EOVs to be developed based on emerging requirements and new technologies. The temporal scale at which any shifts in biological systems will be detected will vary across the EOVs, the properties being monitored and the length of the existing time-series. Global implementation to deliver useful products will require collaboration of the scientific and policy sectors and a significant commitment to improve human and infrastructure capacity across the globe, including the development of new, more automated observing technologies, and encouraging the application of international standards and best practices

Experts Meeting on Sources of Tsunamis in the Lesser Antilles Fort-de-France, Martinique (France) 18–20 March 2019

The Intergovernmental Oceanographic Commission (IOC) of UNESCO supported a Group of Experts meeting on Lesser Antilles tsunami sources to better understand the uncertainties associated with the Lesser Antilles Trench and the nearby volcanic activity. The 3-day experts meeting was held from 18 to 20 March 2019 on the French Lesser Antilles island of Martinique, France. The purpose of the experts meeting was to identify and quantify tsunami sources of both tectonic and volcanic origins, and related hazards and risks to support holistic risk management for the Lesser Antilles (preparedness, mitigation, response, and recovery). Tsunamis from seismic and volcanic sources could have widespread impacts on the population health and economy of the Lesser Antilles. There are historical precedents for tsunamis generated by earthquakes associated with the Lesser Antilles Trench and volcanic activity. A very large tsunami associated with the Lesser Antilles Trench has the potential to cause widespread loss of life, damage and disruption to the region. Similarly, volcanic activity along the Lesser Antilles volcanic arc could potentially generate locally devastating tsunamis that would compound the volcanic crisis. The Lesser Antilles are made up of small islands with an increasing dependency on coastal-based tourism. Moreover, the population of these island nations and their infrastructure are concentrated in areas particularly prone to tsunami effects, low-lying coastal areas. The meeting in Martinique aimed to focus on the uncertainties in tsunami hazard assessment for the Lesser Antilles and identify possible tsunami sources. The outcomes of the meeting can be used for Lesser Antilles hazard and risk assessment studies. The invited experts analysed credible tsunami sources, for which they identified the following groups of sources related to the subduction of North and South America plates beneath the Caribbean plate with potential to impact the Lesser Antilles: 1. Subduction Zone related sources consist of tsunami sources stemming from the interaction of North and South America plates with the Caribbean producing shallow thrust events capable of inducing near-field catastrophic tsunamis. Events in this category include sources tentatively similar to the 8 February 1843 earthquake (M7.5-8.0; Bernard and Lambert, 1988). 2. Island Arc Normal sources consist of crustal faults within the arc itself and thus not directly related to the subduction process. Tsunamigenic sources in this category are smaller events with smaller shallow rupture areas that are oriented perpendicular to the arc. An example of such a source is the M7.4 October 8, 1974 event that ruptured a normal fault oriented perpendicular to the arc between Antigua and Barbuda. 3. Island Arc Parallel sources consist of crustal faults within the arc itself and thus not related directly to the subduction process. Tsunamigenic sources in this category are smaller events with smaller shallow rupture areas that are oriented parallel to the arc. An example of such a source is the M6.3 November 21, 2004 earthquake along the Roseau fault between Guadeloupe and Dominica, an oblique fault oriented parallel to the arc axis. 4. Volcanic-induced sources consist of tsunamis generated by the explosive nature of volcanic islands either by volcanic eruption of underwater volcanoes, debris flows, or lateral collapse of volcanic islands. An example of such a source is the tsunami generated by debris flows at the volcano crisis of Mont Pelée in Saint Pierre, Martinique, on 4 May 1902