Preface

The tsunami that hit the coastal and island regions of India on 26 December 2004 has left a feeling that we need to be better prepared for such events. This feeling found expression during the recent Brainstorming Session on the Great Tsunami of 26 th December 2004, in South Asia organized jointly by Department of Science & Technology (DST), Department of Ocean Development (DOD), Council of Scientific and Industrial Research (CSIR) and Indian National Science Academy (INSA) on 21-22 January, 2005, at INSA, New Delhi. Over 300 participants, including several distinguished Fellows of the academy and leading experts from six countries, attended the session.

The contours of a National Action Plan were drawn at the end with a broad outline of an early warning system, but the importance of an integrated approach was highlighted. The consensus that emerged during the brainstorming session was that while steps are being taken to set up an operational warning system, there is a need to evolve a national research agenda that will take a holistic look at the country's coastal hazard preparedness.

Keeping this in view, a two-day workshop was held during 18-19 February 2005 at the National Institute of Oceanography, Goa. The aim of this workshop, National Workshop on Formulation of Science Plan for “Coastal Hazard Preparedness” , was to prepare an action plan as part of a long-term strategy to develop the science behind coastal hazard preparedness. The workshop was attended by 87 researchers from around the country (see Annexure II). The workshop discussed the research proposals that were put forth by the participants, and synthesized them into the science plan that is contained in this document. The programme of the workshop is given in Annexure I. We hope to have the science plan translated into research projects during the course of this year with the help of the DST, DOD and CSIR.

Please send your comments/ suggestions on the science plan and its implementation to Dr. K.S. Krishna, National Institute of Oceanography, Dona Paula, Goa 403004. E-mail: krishna@darya.nio.org , phone: 0832-2450384, fax: 0832-2450609

Local Organizing Committee

Contents

1. Executive Summary

2. Background

3. Vulnerability of coastal areas

4. Potential coastal hazards

5. Coastal Hazard Preparedness

6. Science issues

7. Implementation plan

8. References

Annexure I: Workshop Programme

Annexure II: List of participants

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The tsunami that hit the coast of India on 26 th December 2004 reminded the country that our 7,000 km long coastline is exposed to hazards and that we are not prepared to face all of them. Preparedness to guard against them requires that we examine scientifically all issues associated with the hazards. Hence science plan, including its implementation to address these issues, was prepared by the “National Workshop on Formulation of a Science Plan for Coastal Hazard Preparedness” held at the National Institute of Oceanography, Goa on 18-19 February 2005. This report summarizes the Science Plan.

Vulnerability of a coastal area of India to coastal hazards depends on a number of factors: (1) coastal population density; (2) dependency of the coastal population on the sea; (3) quality of construction in the coastal areas; (4) nature of physical environment (such as presence/ absence of mangrove forests at the coast); (5) state of development; (6) location and type of hazards; and (7) availability of insurance cover.

The coastal hazards that can occur along the coast of India are: (i) storm surges (half a dozen per year); (2) tsunami (one to two every century); (3) coastal pollution due to industrial and domestic effluents; (4) coastal erosion; (5) oil spills; (6) harmful algal blooms; (7) submarine mudslides; (8) hazards related to global climate change. The magnitude of the impact of one of the hazards depends on two parameters: the impact per unit time and the duration of the hazard. While a tsunami may catch public attention because of its high impact per unit time, coastal pollution may be equally hazardous in the long run because of increase in diseases due to pollution of coastal waters.

Preparedness for such hazards depends on: (1) awareness of the hazards; (2) appreciation of the vulnerability to the hazard; (3) ability to predict the hazard either by deterministic or stochastic means; (4) readiness of a community to respond; and (5) level of education about the hazards in the coastal community.

This Science Plan discusses science issues associated with the above elements of preparedness against vulnerability to the coastal hazards found along the coastline of India. The issues are categorized into the following seven areas.

•  Identification of past storm surges and tsunami in tide-gauge data, and their simulation

•  Reconstruction of time series of past storm surges and tsunami from geological record

•  Geomorphology, near-shore bathymetry, and coastal inundation

•  Coastal pollution

•  Seismicity

•  Engineering

•  Education

After discussing the issues that need to be addressed under each of the areas above, the Science Plan goes on to discuss the desired studies that need to be carried out to implement the plan. These have been drawn over 70 brief research proposals that were discussed during the workshop.

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2. Background

The tsunami that hit the south Asian countries on 26 December 2004 served as a rude reminder that our coastal areas, so very much preferred for settlement that about 25% of India's population lives in the coastal zone, suffered from hazards of which we were not always aware. The death toll in India - estimated to be about 15000, but perhaps higher - led to an immediate response from individuals, universities, government agencies, and others to prepare a response to what the tsunami had reminded us of our vulnerability to coastal hazards. It was felt that we needed to take a holistic look at possible sources of coastal hazards and adopt a concerted approach towards our preparedness for these.

At the Brainstorming Session on the Great Tsunami of 26 December 2004 organised by the Department of Science and Technology (DST) in association with the Department of Ocean Development (DOD), the Council of Scientific and Industrial Research (CSIR), and the Indian National Science Academy (INSA), it was decided that while we develop systems for warning of the probable occurrences of coastal hazards, we should also develop a plan that builds a better foundation for coastal hazard preparedness for the country.

This was followed by a National workshop on formulation of a Science Plan for Coastal Hazard Preparedness at the National Institute of Oceanography (NIO), Goa (18–19 February 2005), in which scientists from different R&D organizations, universities, and government departments participated. The deliberations, which were based on a draft science plan circulated among the participants at the start of the workshop and on the proposals received from them, resulted in a science plan leading to preparedness to face coastal hazards. This document summarizes the different coastal hazards that the coast of India is vulnerable to, discusses the science issues to be addressed to quantify these hazards, and proposes an action plan to implement the science plan.

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3. Vulnerability of coastal areas

India has a long coastline (~7500 km) and a large Exclusive Economic Zone (EEZ) (~2 million sq. km.) that includes two major groups of islands, all of which are susceptible to different coastal hazards. Peninsular India comprises of nine populous states, with a significant component of their economy in some way related to the sea. This includes fishing, shipping, ports and harbours, tourism and allied industries. The last few years have also seen new investment being made in our coastal zone (on the continental shelf and slope) for oil and gas exploration. The investment - over US$ two billion per year by some estimates - involves construction of platforms, pipelines, and other structures. These could eventually become a critical component of the national economy. With these new developments also come new threats: while these offshore structures are vulnerable to storm surges or tsunami or submarine mudslides (these hazards are described in the next section), they are also a potential source of oil spills, which too constitute a hazard affecting fisheries and coastal environment. The growing tourism industry is also a major stakeholder because any coastal disaster has direct fallout and often paralyses the economy in areas dependent on tourism. There are several considerations that contribute towards the vulnerability of the coastal areas.

(i) Coastal population density

Coastal areas are the most preferred locations for human settlement. 25% of India's population lives within 50 km of the coastline. Virtually all the mega-cities are located on the coast; this can be seen in a population density map (Fig. 1).

It is also possible to appreciate vulnerability of the coastal region to damage from coastal hazards from the picture assembled by NRSA (National Remote Sensing Agency) on the lighted areas of India during Diwali (Fig. 2, NRSA 2005), wherein the intensity of lights serve as a proxy for investment in life and property.

(ii) Dependency on the sea

An important component of the coastal population is the seafaring community, of which fishermen form a sizeable part. Their vulnerability can be appreciated from Table 1, which shows that about 0.5 million fishermen are exposed to the vagaries of nature in the offshore areas every day and that well over 3500 villages are exposed to the hazards that coastal areas have to confront.

Table 1: Statistics of India's fishing community.

(iii) Quality of construction

It has often been pointed out that earthquakes of not particularly high magnitude prove to be “killers” in India because of the poor quality of construction of buildings. Vulnerability to tsunami and storm surges is no different. Poorly constructed buildings in coastal areas turn into killers in the face of these hazards.

(iv) Physical environment

The recent tsunami showed that certain areas become far more vulnerable than other, even neighbouring, areas owing to differences in physical environment. Coastal topographic slope and the absence of vegetation (and its type) are some of the factors that determine vulnerability to coastal hazards. A recently coined word is “bio-shields”, which depicts how naturally occurring plants and trees in coastal areas shield a region from the ferocity of storms and tsunami.

(v) State of development

The ability of a community to respond to a natural hazard is dependent on the state of infrastructure, communication, roads, and ability to mobilize resources such as medical facilities. Our ability to respond to all hazards is not necessarily the same. The requirement also varies. For example, a warning system for tsunami will have to work within a much shorter time frame than one for storm surges because the latter develops gradually and the development of its cause (cyclones or storms) can be tracked more easily with available technology. This also implies that emergency procedures will have to be different for each hazard, and our ability to respond effectively is critically dependent on mass awareness, which, in turn, is critically linked to education.

(vi) Location and type of hazard

The vulnerability also depends on the location of the site and the type of hazard. For example, damage caused due to a coastal event in a business centre such as Mumbai has a greater and more widespread impact on the economy, and therefore affects a much larger population than is resident in the affected region, than similar or even worse damage in a less developed area.

On the other hand, the impact on an offshore oil platform may not be as much on life: far fewer people are directly at risk in the event of a cyclones, but it is the disruption such an event can cause to the economy, thereby affecting practically the entire country through a cascading effect, that makes it critical to develop a better preparedness.

(vii) Insurance cover

The developed world prepares for hazards by estimating the expected losses from statistics on hazards and by providing insurance cover for the expected damage. Insurance cover does not reduce loss of life or property; it does, however, guarantee resources for recovery, and vulnerability increases in the absence of such guarantees.

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4. Potential coastal hazards

4.1 Causes and effects of different coastal hazards

(i) Storm surges: Storms form over warm seas (sea surface temperature should exceed ~ 28 ° C in the Indian Ocean) ( Gadgil et al. 1984). The frequency of storms is highest in the Bay of Bengal (Fig. 3). Though storms are tracked better today owing to satellite remote sensing, there is need for improvement in modelling of storm track and intensity because this is today one of the weakest links in storm-surge prediction. The impact of a storm as it crosses a coast is caused by the surge due to strong winds and low atmospheric pressure, and the high waves riding over the surge.

(ii) Tsunami: Tsunami is caused by vertical displacement of the water column owing to earthquakes, volcanic eruptions, and submarine mudslides. Though they are almost undetectable in the open sea owing to their low amplitude, the tsunami waves can reach heights exceeding 10 m in the vicinity of a coast. The high impact they have on a coast is due to high water velocity and wave height. Tsunami is not as frequent as storm surges along the Indian coast (Table 2).

Table 2: Percentage of tsunami worldwide (Table 1.1 in Bryant 2001)

(iii) Pollution due to industrial and domestic effluents: The coastal area of the country has several major cities, with the consequent high concentration of industrial and domestic effluents. About 80% of municipal wastewater and industrial effluents that contain heavy metals or persistent organic pollutants are discharged into the coastal seas; they are dispersed in the near-coastal seas by tidal currents. Pollution has an impact on the marine food chain, and eventually through seafood on human health.

(iv) Coastal erosion: Coasts are subject to almost continuous change, and can either erode (retreat) or build seawards (accrete). Erosion is a natural phenomenon, but it can also be caused and exacerbated by anthropogenic activities. It is affected by several factors that can be site-specific: near-shore topography and geomorphology, drainage patterns of local streams, etc. Erosion poses a threat to any activity, especially construction, in the coastal zone.

(v) Oil spills: These are caused by accidents involving tankers, barges, pipelines, refineries, and storage facilities; this usually happens while the oil is being transported. The oil usually spreads out rapidly across the water surface to form a thin layer that we call “oil spill”. Depending on the circumstances, oil spills can harm marine birds and mammals, and can also harm fish and shellfish. As with pollution, the effect can cascade up the food chain to human beings.

(vi) Harmful algal blooms (HAB): Eutrophication of waters caused by excessive nutrients, especially nitrogen, leads to potentially harmful algal blooms (HAB). They result in rapid growth of an algal species that contains toxins or causes a negative impact on natural resources or human beings; HABs can occur naturally, but are exacerbated by pollution. HABs are a serious coastal problem, affecting the coastal ecosystem and, through the food-chain cascade, eventually human health; apart from the impact on tourism and recreation through their impact on health, they also affect this industry through visual pollution of the coastal waters.

(vii) Submarine mudslides: As on land, mudslides can occur on the continental slopes; apart from the obvious risk they pose to offshore platforms, they can also trigger tsunami.

(viii) Hazards related to global climate change: Anthropogenic impact on climate is more certain now owing to increasing confidence in observations and models. There have been suggestions that the frequency of storms in the Bay of Bengal might increase ( http://ipcc-wg1.ucar.edu/ ). Since surges due to storms already pose a considerable threat to the region (Fig. 3), any increase in the intensity and frequency owing to global changes in climate will exacerbate the hazard.

4.2 Magnitude of impact of different coastal hazards

Each of the hazards mentioned above has its own unique features in terms of the duration of an event and its impact on life and property. The schematic in Fig. 4 gives an idea of each hazard in terms of these two variables. Some hazards like tsunami and storm surges are short-lived, i.e. they are events, but each event has a high impact per unit time. They cause considerable damage in a short time and therefore are more easily embedded in our conscious mind. If their frequency of occurrence, however, happens to be low, as in the case of tsunami along the Indian coast, they disappear from our conscious mind after a while. Other hazards like coastal pollution occur over a long duration, i.e. they are not events but processes , and have a small impact per unit time. Any damage they cause occurs gradually and in an incremental fashion. Hence, these long-duration, low-impact hazards are less easily recognized and do not register as strongly in our consciousness as the short-duration, high-impact events. That they act more persistently, however, implies that the cumulative effect of these processes over some time usually will exceed that of the high-impact events.

Some hazards like HABs may not cause loss of life, but can lead to outbreak of disease, thereby affecting normal life and the economy, if they find their way up the food chain to human beings. Some hazards like secular sea-level rise may not cause fatalities, but have the potential for disrupting life if it becomes necessary to abandon flourishing coastal towns and cities. Likewise, coastal erosion has a serious impact on coastal settlements and the infrastructure along the coastline. Submarine mudslides too, though not affecting life directly, have the potential to disrupt economy on a large scale because they directly affect the basis for modern industrial civilisation: fossil fuels.

It is necessary to quantify these hazards to determine our vulnerability to each of them. Information is needed on the frequency of their occurrence, on their spatial distribution, and on the magnitudes of the extremes associated with them. This is essential if their economic impact is to be assessed; insurance premium calculations, for example, require an estimate of the potential risk. Since these hazards do not affect all coastal regions uniformly, it is essential to map them quantitatively. Table 3 provides a summary of our knowledge about different coastal hazards.

Table 3: S ummary of coastal hazards and our current knowledge of these hazards with
respect to India.

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5. Coastal Hazard Preparedness

Having examined the vulnerability to coastal hazards along the Indian coast, the following elements need to be considered for our preparedness for such hazards:

(i) awareness of (a) evolution of a hazard based on past experience and its frequency of occurrence, and (b) distribution of the magnitude of past hazardous events;

(ii) appreciation (quantitative as far as possible) of vulnerability to a hazard;

(iii) ability to predict either deterministically or stochastically;

(iv) response readiness before and after the hazard(ous) event; and

(v) education at all levels.

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6. Science issues

The science issues that need to be addressed to improve our coastal hazard preparedness are the following.

(i) Identification of past storm surges and tsunami in tide-gauge data and their simulation

Tide-gauge data are available for several Indian coastal stations for over half a century; some of these records go back over a century, making them the most reliable record of past tsunami and storm-surge events. The past tsunami events may have escaped us either because of their infrequent occurrence, implying a long gap between two events, or because of their impact having been low, or because the usual practice of digitizing these data at one-hour interval is not enough for capturing tsunami, which have a smaller period.

Identifying past tsunami events in tide-gauge records and developing the ability to simulate them will allow us to generate reliable statistics on this hazard. In the case of tsunami, confidence in a model is critical because it will allow us to prepare a scenario database that can be used for ascertaining which areas are vulnerable once a tsunami is triggered in some part of the Indian Ocean; given that not many tsunami have occurred in the Indian Ocean during the last century, model-based scenarios constitute a viable risk-assessment tool. Such scenarios are critical for the Indian Ocean because the travel time is too small (less than three hours on 26 December 2004) to permit a model to be run after the cause is detected. Tsunami models have to be developed specifically for the Indian Ocean because tsunami patterns here are different from those in the Pacific. The smaller basin size restricts the dissipation and dispersion of the waves, making wave reflection important. Interaction with currents, tides, and winds also need to be considered. A good, high-resolution map of near-shore bathymetry and near-coastal topography is essential for mapping the tsunami run-up. The primary use of these models will be to identify the vulnerable areas. For a warning system, however, a more promising approach is to compute the Green's function for the shallow-water equations for the bathymetry of the Indian Ocean. With present-day computers, it may be possible to use this approach in conjunction with bottom-pressure gauges to discern the source of the tsunami and to make a quick assessment of the risk.

Tide-gauge data also record storm surges. Identifying past surges and simulating them accurately (with validation based on tide-gauge data rather than on eyewitness accounts) will lead to better, more reliable models and statistics. Since the damage is caused not just by the surge, but also by the high waves due to the storm, it is necessary to identify high-wave concentration zones. In storm-surge modeling, the major bottleneck today is the prediction of cyclone tracks. Improving predictions by using super-ensembles of different models is promising. Climate change scenarios have often suggested an increase in the frequency and intensity of storms in the Bay of Bengal, with a corresponding increase in the extent of the threat posed by storm surges. Ascertaining the risk due to this hazard therefore makes it necessary to simulate surges forced by wind “data” from climate models.

The complexity of the coastal topography can perhaps be tackled better using hybrid methods involving finite elements and fractals. Soft computing and artificial intelligence tools like neural networks (ANN) or fuzzy logic can be used to complement the results of the differential-equation-based numerical models.

(ii) Reconstruction of time series of past storm surges and tsunami from geological records

Instrumental data records go back a century at the most. Hence, as with climate studies, it is necessary to use proxies to construct a longer time series for generating better statistics, especially for extreme events. Unlike instrumental data, which allow detection of events of a wide range of intensities, it is likely that the geological proxies obtained from cores will yield information only on the bigger events. It is, however, necessary to assemble the information into a quantitative framework that coastal engineers can use.

Such records of storm surges or tsunami, submarine mudslides, and volcanic eruptions need to be created to estimate the likelihood of mega extreme events along the Indian coast. Studies elsewhere, not much more complete than along the Indian coast, suggest that catastrophic mega events (especially due to tsunami) are not as rare as thought at present ( Bryant 2001). Extreme events disrupt normal sedimentary deposition and leave an imprint in the sediment strata. By a careful study of sedimentary sequences through time and space, it is possible to unravel the past events and determine their frequency and periodicity. It is therefore necessary to build a record of storm surges, tsunami, submarine slope failures, and volcanism from the sediment strata along the coast and offshore regions of India. Information on submarine mudslides is particularly critical in view of the growth in offshore exploration for oil and natural gas.

(iii) Geomorphology, near-shore bathymetry, and coastal inundation

Both storm surges and tsunami cause devastation in the vicinity of the coast. The damage they can cause in a region is critically influenced by the near-shore bathymetry and geomorphology of the region. Surges and tsunami waves tend to concentrate in certain locations because of wave refraction due to local bathymetry; the run-up and extent of inundation is similarly a function of land topography and near-coastal geomorphology. Hence, information on geomorphology and near-shore bathymetry (say water depth less than 20 m) is a crucial input to models for coastal inundation.

The coastal areas are also vulnerable to oil spills. Since all parts of the coast are not equally at risk, it is necessary to identify and classify ecologically sensitive areas. Mapping the vulnerable areas is essential for formulating emergency evacuation plans. Though mapping the geomorphology is a major task by itself, what is more critical is making the exercise quantitative. Vegetation such as mangroves is known to help mitigate the effects of storm surges and tsunami. It is, however, necessary to quantify the protection such natural buffer zones, now called bio-shields, provide to coastal habitation. For example, it is necessary to determine the thresholds beyond which they cease to be effective and the extent of protection they provide.

The 26 th December tsunami, as the storm surges in recent times, has left their imprint on coastal geomorphology. The tsunami caused severe erosion in places and deposited heavy minerals in several locations. Such morphological changes must have also occurred in the past, with the bigger events leaving a major mark. This is therefore another tool for identifying past events and for determining their potential impact. A more pervasive coastal hazard is erosion. Identifying areas vulnerable to erosion and quantifying its extent is essential for mitigation and formulating area-specific regulations and building codes.

(iv) Coastal pollution

With the boom in the economy of the coastal states, there is an increase in the industrial activity in the coastal zone along with an increase in the population resident there; with modern industrial activity being heavily dependent on fossil fuels, the risk of pollution owing to an oil spill is greater today. Any industry that is set up in the coastal zone needs to go through an environmental impact assessment (EIA); hence, many EIA studies have been conducted in the coastal waters of India. There is a need to integrate the results of the EIA studies to generate a national database, and to determine the “carrying capacity” of the coastal waters of India. A beginning towards determining the carrying capacity of Indian coastal waters has been made with the ICMAM (Integrated Coastal and Marine Area Management) and COMAPS (Coastal Ocean Monitoring And Prediction System) programmes, but there clearly is much that still needs to be done.

In addition to the pollution due to industrial and domestic effluents, there are natural pollution hazards like harmful algal blooms (HABs). HABs have an impact on the marine ecosystem and they could be enhanced by anthropogenic pollution. Though such blooms have been observed along the Indian coast, particularly off the west coast, there is no systematic study that documents them, their causes, and their potential impact on environment and also commercial activities such as fishing, aquaculture, tourism, etc.

(v) Seismicity

Submarine earthquakes, which can generate tsunamis, could not only be a threat to offshore platforms, but also to coastal installations and habitat. It is therefore necessary to monitor and evaluate the return periods of strong earthquakes, and link seismic activity to the mudslides on the continental slope off coastal areas of the country. Since much of the tsunami threat to India comes from the seismically active regions of Indian Ocean – the Andaman-Java-Sumatra and Makran subduction zones-, it is necessary to map the stress field of active regions to determine the high potential for future strong earthquakes, and to measure periodically the coseismic deformations and identify such deformational features in the island-arc and trench region. There is also a need for comprehensive delineation and characterization of seismotectonic units, lineaments, and major and minor fault systems in order to assess seismicity and possible sites of future tsunamigenic earthquakes in the Indian Ocean.

(vi) Engineering

Quantitative risk assessment, leading to better preparedness, is contingent upon good instrumentation and easy availability of data. Long-term monitoring using automatic instrumentation is essential for identifying a hazard before or as soon as it occurs. These data are also crucial for validating models (tsunami or storm surges). Engineering solutions for control and remediation are important where and when the cheaper and less intrusive natural methods are ineffective. With exploration for oil gaining momentum, offshore structural engineering is gaining importance. The potential threat to such structures from submarine mudslides necessitates engineering design solutions to mitigate the impact. Since poor quality of construction has been identified as one of the causes of higher fatalities due to natural hazards in India, quantification of these hazards must also lead to better regulations and viable building codes.

(vii) Education

Different sections of society need to be educated about the possible causes, effects and means for preparedness for different types of coastal hazards. For better preparedness, open access to information is needed to build greater public awareness. It is not only necessary that good, quantitative research be done on coastal hazards, but also that the results of such research reach those who need them: planners, developers, insurers, the public, and also the academia who generate such information. The information must therefore be available in an easily accessible, publicly documented format to enable wide and open access to information. Experience with disaster management programmes throughout the world shows that they have to be inclusive in order to succeed. It is critical that all sections of the population, including women, need to be involved. Apart from education, this aspect of preparedness calls for an interaction between scientists, who study the physical aspects, and social scientists, who study the way society deals with them.

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7. Implementation plan

The implementation plan proposed below takes into account the science issues discussed above and the research programmes proposed by the participants in the workshop.

(i) Identification of past storm surges and tsunami in tide-gauge data and their simulation

The action plan for this category is presented under five heads. The first of these (creation of a digital data base) is a pre-requisite for the implementation of the second and third (modeling).

Tide-gauge data

•  Digitise the tide-gauge charts available with Survey of India (SOI) (for the past 120 years or so) at a finer interval (say 5 min.), so that the signals due to tsunami will not be lost. This should be taken up in collaboration with SOI.

•  Collect the information on past events of weather disturbances (cyclones, storm surges, etc.) and earthquakes from all available sources and corroborate them with the extreme sea level signals (storm surges or tsunami) identified in the tide-gauge records.

•  Analyse the events identified in the tide-gauge records to determine their statistics (return periods, frequency of occurrence, etc.)

Tsunami modeling

•  Develop numerical models for tsunami in the Indian Ocean.

•  Simulate past tsunami events identified in the tide-gauge records.

•  When required, use inverse methodology to reconcile source parameters with arrival  times.

•  Construct Green's function for the Indian Ocean. Use the output of numerical models to test the Green's function approach. This is a fast, computationally efficient method for predicting tsunami propagation in the Indian Ocean.

•  Develop finite-element and fractal models for tsunami run-up simulations, and soft computing tools (ANN, Fuzzy systems, hybrid approaches) to evaluate water levels due to tsunami.

Storm surge modeling

•  Simulate past storm surge events identified in the tide-gauge records.

•  Run storm surge simulations using HadRM3 winds for future surge scenarios.

•  Develop finite-element and fractal models for surge run-up simulations, and soft computing tools (ANN, Fuzzy systems, hybrid approaches) to evaluate water levels due to surges.

Waves

•  Model wave climate along the coast of India for different cyclones and identify high wave concentration zones.

Prediction of cyclone tracks

•  Improve model initial conditions using 3D/4D variational data assimilation.

•  Generate ensemble members based on WRF model platform with different dynamical and physical frame works.

•  Improve model parameterizations.

(ii) Reconstruction of time series of past storm surges and tsunami from geological records

Evaluation of available data and identification of reliable proxies (sedimentological, paleontological, geochemical, isotopic, geomorphological and structural) is the first action required under this category. The rest of the action plan is divided on the basis of the hazard.

Storm surges and tsunami

•  Acquire sediment cores from selected areas of sedimentation near the coast (lagoons, dunes, deltas, coastal lakes, peat beds, and low-lying coastal plains, high sedimentation regions of continental shelf).

•  Look for variations in grain size and faunal composition and geo-chemical proxies at close intervals in the cores. Presence of coarser material (sands, shells) in otherwise fine-grained strata indicates deposition resulting from a storm surge or tsunami. Confirm these events with other paleontological and geochemical proxies and date the sediments with isotopic methods to assign ages.

•  If possible, distinguish between deposits due to storm surges and tsunami on the basis of the number of layers present, aerial extent, and grain-size characteristics.

Submarine mudslides

•  Collate available sub-bottom profiler data from the shelf and slope regions and analyse these records for slope failures.

•  Acquire high-resolution bathymetry, shallow seismic, and side-scan sonar data for delineating their aerial extent.

•  Acquire sediment cores where mass flows are shallow and ascertain age of the deposit through 210 Pb, 137 Cs or 14 C dating techniques.

•  Tie some of the shallow seismic profiles with drill sites and assign ages for older events.

•  Build a record of slope failures and mass flows through time and space and determine the frequency of occurrence.

Volcanism

•  Acquire sediment cores in the regions of volcanic activity, especially in the Andaman Sea.

•  Perform sedimentological and geochemical analyses at close intervals. Based on grain size, grain morphology, and major, trace, and rare-earth element geochemistry, identify volcanic deposition.

•  Date the horizons of volcanic material to determine age and periodicity of these events.

(iii) Geomorphology, near-shore bathymetry, coastal inundation

Geological

•  Detailed mapping of coastal topography, nearshore and shelf bathymetry (including inlet configuration) is needed for providing input for predictive models for inundation vulnerability.

•  Large-scale mapping of coastal landforms (particularly the wave protective beach ridges, berms etc.) is needed.

•  Map near-shore bathymetry (water depth less than 20 m). Work is already on for mapping the bathymetry beyond the 10 m isobath under the EEZ programme of the Department of Ocean Development (DOD), but this needs to be extended up to the coast because much of the amplification of tsunami and storm-surge waves occurs in this regime.

•  Understand sediment dynamics, coastal processes and shoreline changes.

•  Quantify extent of erosion along the Indian coast (using a combination of remote sensing and field surveys) and determine the cause (natural or anthropogenic). This is essential for the success of any scheme for mitigating the effects of erosion.

•  Use high-resolution models with this high-resolution bathymetry and near-shore topography and geomorphology as inputs to determine the regions at risk from inundation.

•  Design suitable experiments to test the viability of natural ecosystems like mangroves and sand dunes as buffer zones. Quantify the extent of protection provided by these bioshields. Identify areas where adequate protection exists and areas where it is possible to generate or regenerate such natural protection. Validate of the effectiveness of these bio-shields.

Output

•  Compilation of relevant data in digital and open-access, GIS-compatible format.

•  Preparation of theme-based coastal atlas (including features like coastal landform, artificial construction, cultivation, extended aquaculture, etc.)

(iv) Coastal pollution

The action plan for this category is presented under two heads: industrial and domestic effluents and harmful algal blooms. This distinction is necessary because the latter, though affected by anthropogenic pollution, also have natural causes.

Industrial and domestic effluents

•  Create a comprehensive database on industrial and domestic effluents released into the Indian coastal waters. Use remote sensing and GIS to generate easily usable digital data.

•  Use isotopes to study the pollutant pathways in the control environment. Use numerical models of coastal circulation and biogeochemistry to quantify the fate of effluents, and to determine the carrying capacity of the coastal waters.

•  Map ecologically sensitive areas using remote sensing and GIS.

Harmful algal blooms

•  Use remote sensing as a tool to detect algal blooms. Provide inputs for generating advisories based on ground-truth validation in such situations using taxonomy and toxin characterization and toxicity evaluation.

•  Initiate process studies at potential sites (identified from remote sensing data to be more prone to such blooms) for developing empirical and predictive numerical models.

•  Install suitable organisms-based watch programme for quantifying toxic or threat constituents and their longevity in the environment for providing necessary advisories through implementing agencies in the respective region.

The above plan delineates what can and should be done on the short term. On the long term, however, the objectives are more holistic and include the following.

•  Capacity building in taxonomy and culture

•  Population ecology (including cyst/resting cells)

•  Prediction models

•  Identification of toxins

•  Bio-magnification and eco-toxicology

•  Toxicity evaluation

•  Decision support system

(v) Seismicity

•  Monitor and evaluate source parameters of earthquakes occurring along plate boundaries in the Indian Ocean and continental margins including evaluation of return periods of strong earthquakes.

•  Determine of crustal (including sedimentary) and upper mantle structure of earthquake prone regions in oceanic and continental margins. Techniques used could be multichannel seismic, Ocean Bottom Seismometry, dynamic inversion of waveforms, tomographic analysis, and surface wave dispersion.

•  Simulate expected ground motion from an oceanic earthquake (particularly with regard to a tsunamigenic earthquake) of presumed magnitude and focal mechanism (including attenuation modeling using Broad Band Seismic Networks).

•  Conduct GPS-based geodetic investigations, including detailed mapping of stress field of active regions.

•  Conduct earthquake precursory studies using seismological, geo-electric, geomagnetic, magnetotelluric, geochemical, electromagnetic and other geophysical and geological methods. Generate remotely sensed data on thermal status of the earthquake prone regions. Make periodic measurements of coseismic deformations and identify such deformational features in the island arc and trench region.

•  Archival of large historic earthquakes, tsunami and their effects in the form of structured and programmable database.

•  Disseminate information in the form of geophysical products from the investigating institutions through a scientific interface to the concerned authorities.

(vi) Engineering

•  Expand existing tide-gauge network and modernise it to enable online data transmission to the concerned monitoring agency (SOI).

•  Expand network of met-ocean data buoys and make the data available to concerned monitoring agency (IMD) and for research. Meteorological and wave data are critical for validating wave models and enabling identification of high wave concentration zones.

•  Identify failure mechanisms in coastal and offshore structures and devise solutions.

•  Evolve better regulations for coastal structures and viable building codes.

(vii) Education

•  Prepare material in the form of print media (stories, comics, and cartoons particularly for school children, brochures, manuals, charts, etc.), audio-visual media, and electronic media for distribution/ dissemination especially in local languages to explain causes and effects of coastal hazards, means to mitigate the effects, and measures for preparedness.

•  Include topics on coastal hazard preparedness in academic curricula: in school, undergraduate, and postgraduate curriculum backed up by teacher's training programme and web based lectures.

•  Use mass communication channels for capacity building among the ‘local population': involve them in data collection and build awareness through lectures, story-telling, plays, theatre, etc. in local languages.

•  Harness the power of the Internet by developing a web portal. Make available data and information on coastal hazards at a single source of reference that is open to all.

•  Make data and information available on the websites: Funding agencies should make it mandatory for the project leaders to place the information / data collected through the project on websites within a stipulated period. Open access to data in a publicly documented, easily accessible format is critical for the viability of any programme aiming at improving our preparedness.

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1. E. Bryant. Tsunami: The underrated hazard . Cambridge University Press, 2001.

2. http://www.Ideo.columbia.edu/%7Esmall/PopMap.html

3. http://ipcc-wg1.ucar.edu/

4. NRSA (National Remote Sensing Agency). NRSA Newsletter, January 2005, Page 13.

5. W.M. Gray. Tropical cyclone genesis . Dept. of Atmos. Sci. Paper No. 232, Colorado State University, Ft. Collins, CO.

6. Gadgil, S., P.V. Joseph, and N.V. Joshi. Ocean-atmosphere coupling over monsoon     regions. Nature, 312, 141–143, 1984.

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Annexure I

National Workshop on Formulation of Science Plan for

“Coastal Hazard Preparedness”

National Institute of Oceanography, Goa

18 - 19 February 2005

PROGRAMME

Venue: Cardium

18 February 2005

0900 – 1000 hrs. Registration

1000 – 1045 hrs. Rationale for the workshop - Dr. S.R. Shetye

1045 – 1115 hrs. Perspectives on Coastal Hazard Preparedness - Dr. Tad Murthy

1115 – 1130 hrs. Tea break

1130 – 1145 hrs. Modalities on discussions - Dr. K.S. Krishna

1145 – 1300 hrs. Directions - Dr. R.N. Singh (Chairman)

Speakers

•  Dr. O.P. Agarwal

•  Dr. P.C. Pandey

•  Dr. V.P. Dimri

•  Dr. S. Kathiroli

•  Dr. Pawan Kumar

1300 – 1400 hrs. Lunch break

1400 – 1800 hrs. Presentation of proposals and Group discussion

19 February 2005

0900 – 1130 hrs. Presentations by Chairmen of various groups

1130 – 1145 hrs. Tea break

1145 – 1215 hrs. Comments on Science Plan - Dr. Tad Murthy

1215 – 1230 hrs. Wrapping up - Dr. S.R. Shetye

1230 – 1245 hrs. Vote of thanks

Presentation of proposals and Group discussion

Group I: Geomorphology and coastal inundation (Venue: Chemistry Hall, 2^nd floor)

Chairman – Dr. B.K. Saha / Dr. G.C. Bhattacharya

Convener – Dr. K.H. Vora

Group II: Reconstruction of past events from geological records (Venue: Cardium)

Chairman – Dr. R. Nigam

Convener – Dr. P.S. Rao

Group III: Seismicity (Venue: Conference Room)

Chairman – Dr. S.K. Arora

Convener – Dr. A.K. Chaubey

Group IV: Identification and simulation of extreme events in sea level records (Venue: Seminar Hall)

Chairman – Prof. M.C. Deo

Convener – Dr. S.C. Shenoi

Group V: Marine Pollution (Venue: Zero Room, basement, MICD)

Chairman – Dr. R.N. Singh

Convener – Dr. A.C. Anil

Group VI: Engineering and Education (Venue: Tower Room)

Chairman – Dr. S. Kathiroli / Prof. V. Sundar

Convener – Dr. M.P. Tapaswi

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Annexure II

List of Participants attended Workshop