Role of IT, remote sensing, GIS and GPS in disaster preparedness

India with its subcontinent size and wide range of climatic and topographic conditions is a country prone to various types of natural and manmade disasters in varying degrees. It has witnessed devastating natural disasters in recent past like earthquakes, floods, droughts, cyclones, landslides, etc.

In the decade 1990-2000, an average of 4344 people lost their lives and about 30 million people were affected by disasters every year. Among all the natural disasters that country faces, river floods are the most frequent and often devastating. The shortfall in the rainfall cause droughts or drought like situation in various parts of the country. India has faced some severe earthquakes causing widespread damage to the life and property.

The country has a coastline of about 8000 km, which is prone to very severe cyclonic formations in the Arabian Sea and Bay of Bengal. Usually more cyclones form in the Bay of Bengal then in the Arabian Sea.

Another major problem faced by the country is in the form of landslides and avalanches. During the last eighty years, India has lost 70,000 lives due to earthquakes or an average of about 900 lives per year. The corresponding average of the whole world is about 18,000 lives per year. Around 30,000 lives have perished in matter of seconds in an earthquake, as in Gujarat earthquake (2001).

The vulnerability of different areas of country to various natural disasters is given below:

1.    About 50-60% of total area of the country is prone to seismic activities of varying intensities.

2.    16% of total area is drought prone and approximately 50 million people are annually affected by drought.

3.    India has a long coastline of 8041km., which is exposed to the tropical cyclones arising from the Bay of Bengal and Arabian Sea.

4.    Also in India river floods are the most frequent and often most devastating.

The disaster management is the range of activities to maintain control over disaster and provide a framework to help, avoid or recover from the impact of the disaster. Disaster management includes Prevention, Mitigation, Preparedness, Response, Recovery and Rehabilitation. Disaster management involves all levels of government. All government, nongovernmental and community-based organizations play a vital role in the process. Modern disaster management goes beyond post-disaster assistance. It now includes predisaster planning and preparedness activities, organizational planning, training, information management and public relations

The disaster management in any region is based on cyclic steps. The disaster management cycle involves four key phases:

i.    Mitigation – includes any activities that prevent a disaster, reduce the chance of a disaster happening, or reduce the damaging effects of unavoidable disasters.
ii.    Preparedness – includes plans or preparations made to save lives or property, and to help the response and rescue service operations.
iii.    Response – includes actions taken to save lives and prevent property damage, and to preserve the environment during emergencies or disasters. The response phase is the implementation of action plans.
iv.    Recovery – includes actions that assist a community to return to a sense of normalcy after a disaster. These four phases usually overlap.

Information and Communication Technology is being used in all the phases, but the usage is more apparent in some phases than in the others.

Communication and media in disaster mitigation

The disasters in India are mainly managed by the government. The government at central level, state level, district level has various roles to play during the disaster situation. Now the voluntary sectors like non-government organizations are also becoming increasingly important because of the various functions they can perform. Effective and reliable communication is vital for disaster reduction. Communication technologies, skills and media are essential for the various important roles they perform in disaster management.

Those roles are:

i.             To Link scientists, disaster mitigation officials, and the public

ii.           To educate the public about disaster preparedness

iii.          To check approaching hazards

iv.          To alert authorities

v.            To warn the people most likely to be affected

vi.          To assess damage

vii.         To collect information, supplies and other resources

viii.       To coordinate resource and relief activities

ix.          To account for missing people

x.            To motivate public, political and institutional responses

Application of Information and Communication Technology in Natural Disaster Management

Information Technology is changing every aspect of human life. It enhances the quality and effectiveness of trade, manufacturing, services, other aspects of human life such as education, research, culture, entertainment, communication, national security, etc.

Disaster management needs drastic improvements in its sources to decrease damage and save the life of people. To achieve this main object, disaster management has to face challenges for data collection, data management, translation integration and communication. IT pays crucial role in this respect. The advanced techniques of information technology such as remote sensing, satellite communication, GIS, etc. can help in planning and implementation of disaster management.

With an increase in the perception towards spreading a culture of prevention in the disaster management scenario, considerable emphasis is now being placed on research and development activities in the area of information technology for disaster preparedness and prevention. This has brought in a significant positive change even though the multitude and frequency of disasters in the country has increased. In most critical phases of some major disasters like earthquakes in Kobe, Japan; Northridge, California and turkey role of electronic communication has provided the most effective, and in some instances perhaps the only means of communication with the outside world. The changing trends have opened up a large number of scientific and technological resources and skills to reduce disaster risk. The Information and Communication Technology tools are discussed below:

1. Internet

In the present era of electronic communication, the Internet provides a useful platform for disaster mitigation communications. The role of Internet is becoming increasingly important because of the following reasons:

a.        It facilitates, the opportunities to enhance the capabilities of addressing hazard awareness and risk management practices before, during, and following emergency events.

b.        Internet sites providing an increasing array of information related to various hazards. Internet Sites also provide more information about the growing number of organizations and professional disciplines addressing them.

c.         It provides a new and potentially revolutionary option for the rapid, automatic, and global dissemination of disaster information. A number of individuals and groups, including several national meteorological services, are experimenting with the Internet for real-time dissemination of weather observation, forecasts, satellite and other data.

d.        Network equally provides the means of access to more reference and resource material to more people, in more ways.

e.         The compilation, retrieval and redistribution of information by centers of interest, of the use by alternative forms of media can expand the utility of the information at the local, national, regional and international levels of interest.

GIS and Remote Sensing

Geographic information technology tools like Geographic Information Systems (GIS) and Remote sensing (RS) support all aspects of disaster management. GIS and RS are essential as effective preparedness, communication and training tool for disaster management. Disaster planning can be very powerful when modeling is incorporated into GIS. Most potential disasters can be modeled. Modeling allows disaster managers to view the scope of a disaster, where the damage may be the greatest, what lives and property at highest risk, and what response resources are required and where GIS can play a very important role in this exercise. The specific GIS applications in the field of Risk the assessment are:

–    Hazard Mapping

–    Threat Maps

–    Disaster Management

–    Records Management

Nevertheless satellites have several limitations in their application for response operations. The most obvious is that a number of satellites cannot see through clouds. Many large scale disasters such as cyclones and floods are generally associated with periods of heavy cloud cover, and consequently the ability to image the ground is greatly restricted. In addition a disaster event must coincide with the overpass of the satellite if it is to be imaged.
Some application of GIS and Remote Sensing in various disasters are as follows:-

Drought

GIS and Remote Sensing can be used in drought relief management such as early warnings of drought conditions will help to plan out the strategies to organize relief work. Satellite data may be used for to target potential ground water sites for taking up well-digging programmes.

Earthquake

GIS and Remote Sensing can be used for preparing seismic hazards maps in order to assess the exact nature of risks.

Floods

Satellite data can be effectively used for mapping and monitoring the flood inundated areas, flood damage assessment, flood hazard zoning and post-flood survey of rivers configuration and protection works.

Cyclone

Advanced techniques like, GIS, remote sensing tools can be used to identify the vulnerable population with the single hazard component. These tools can be used to calculate state level population affected by different type of storms. But, calculating vulnerability by GIS with multiple hazards and coping capacity is not easy job for decision makers.

Landslides

Landslide zonation map comprise a map demarcating the stretches or area of varying degree of anticipated slope stability or instability. The map has an inbuilt element of forecasting and is hence of probabilistic nature. Depending upon the methodology adopted and the comprehensiveness of the input data used, a landslide hazard zonation map able to provide help concerning some or all of the following:-

–    Location

–    Extent of the slope area likely to be affected and

–    Rate of mass movement of the slope mass

Search and Rescue

GIS cab be used in carrying out search and rescue operations in a more effective manner by identifying areas that are disasters prone and zoning them accordingly to risk magnitudes.

Warning and Forecasting System

An advance system of forecasting, monitoring and issuing early warnings plays the most significant part in determining whether a natural hazard will assume disastrous proportions or not. The country has the following forecasting systems:

Indian Meteorological Department (IMD)

Indian Meteorological Department provides cyclone warnings from the Area Cyclone Warning Centres (ACWCs) It has developed the necessary infrastructure to originate and disseminate the cyclone warnings at appropriate levels. It has made operational a satellite based communication system called Cyclone Warning Dissemination System for direct dissemination of cyclone warnings to the cyclone prone coastal areas. IMD runs operationally a Limited area Analysis and Forecast System (LAFS), based on an Optimal Interpretation (OI) analysis and a limited area Primitive Equation (PE) model, to provide numerical guidance.

National Remote Sensing Agency (NRSA)

Long-term drought proofing programmes on the natural resources of the district have been greatly helped by the use of satellite data obtained by NRSA. Satellite data can be used very effectively for mapping and monitoring the flood-inundated areas, flood damage assessment, flood hazard zoning and past flood survey of river configuration and protection works.

Seismological Observations

Seismological observations in the country are made through national network of 36 seismic stations operated by the IMD, which is the nodal agency. These stations have collected data over long periods of time.

Warning System for Drought

The National Agricultural Drought Assessment and Management System (NADAMS) has been developed by the Department of Space for the Department of Agriculture and Cooperation, and is primarily based on monitoring of vegetation status through National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution (AVHR) data.

The drought assessment is based on a comparative evaluation of satellite observed green vegetation cover (both area and greenness) of a district in any specific time period, with that of any similar period in previous years.

Flood Forecasting

The Central Water Commission (CWC), Ministry of Water Resources, issues floods forecasts and warnings. These are used for alerting the public and for taking appropriate measures by concerned administrative and state engineering agencies in the flood hazard mitigation. Information is gathered from the CWC’s vast network of Forecasting Stations on various rivers in the country.

Cyclone Tracking

Information on cyclone warnings is furnished on a real-time basis to the control room set up in the Ministry of Agriculture, Government of India. High power Cyclone Detection Radars (CDRs) that are installed along the coastal belt of India have proved to be a very useful tool to the cyclone warning work. These radars can locate and track approaching Tropical Cyclones within a range of 400 km. Satellite imagery received from weather satellite is extensively used in detecting the development and movement of Tropical Cyclones over oceanic regions, particularly when they are beyond the range of the coastal radars. The existing mode of dissemination of cyclone warnings to various government officials is through high priority telegrams, telephones, telex and fax.

Disaster alert through cell phones

The Ministry of Science and Technology of India has developed the world’s first of its kind multilingual disaster alert system – National Disaster Information System (NDIS) – that will transmit Tsunami and cyclone warning through mobile phones in the form of SMS, within 30 seconds of a weather satellite or an earthquake observatory giving alert signals.   The SMS alerts will be made in over 100 languages including 14 regional languages like Tamil, Kannada, Telugu, Bengali, Malayalam, Hindi and Oriya. The SMS alerts will be followed by voice alerts on the mobile phones as well as fixed phones. The NDIS server first receives the warning from the meteorological department alert system before converting it into an SMS in two seconds. In the next 19 seconds, the software translates the alert into multiple languages. The SMS reaches the user in 30 seconds.

Satellite Radio Application

Satellite radio can play a key role during both the disaster warning and disaster recovery phases. Its key advantage is the ability to work even outside of areas not covered by normal radio channels. Satellite radio can also be of help when the transmission towers of the normal radio channels are damaged in a disaster.

The integration of Global Navigation Satellite System data, Geographic Information System, and Remote Sensing data have been and are still being used in wide range of applications.

The utilization of geomatic technologies can have a significant contribution to disaster mitigation. More so, Global Navigation Satellite System (GNSS) is one of the geomatic technologies that can monitor precisely through emitting of time signals allowing users on or above the earth surface to determine the positions with high accuracy. GNSS can also be used to precisely monitor deformation at scale in real time under any weather, at any time of the day. With Global positioning system (GPS) module attached to a hardware platform, data on the point of observation at hazard site can be received in real-time. Supported this notion of the importance of real-time or, at least, near-real-time imagery in emergency response stating natural and man-made disaster creates a need for rapid comprehensive and reliable information on the nature, extend and actual consequences of an event.

GPS application in disaster event

The importance of GPS application in monitoring and managing disaster events cannot be overemphasized. This is because GPS is used in providing real-time information of location with high precision that can help in managing each of the processes of disaster event starting from pre-disaster, during disaster and post-disaster event.

Landslide Study Using GPS Technologies

Land displacement monitoring in a certain landslide prone areas involves monitoring of gradual changes in distance, height difference and coordinates of station within the area under study. Since GPS is a passive, all-weather satellite based navigation and positioning system, which is designed to provide precise three-dimensional position and velocity, as well as time information on a continuous worldwide basis.

Global positioning system can provide a relatively wide spectrum of positioning accuracy, from high accuracy level (mm level) to a normal level (a few meter levels). For the purpose of monitoring landslide phenomenon of little magnitude, the relative positioning accuracy required should be in mm level. And the best method that can achieve that is the GPS static survey based on phase data with stringent and cautious measurement and data processing

GPS Application in Landslide Monitoring

The basic information required from the data of any earth observation satellite could be geological, morphological or land use driven which can help in assessing landslide effects and causes. The static method of survey was used by to study landslide displacement phenomenon. During the study GPS was used in providing the precise coordinates of the susceptible areas of displacement at certain intervals while studying the characteristics and rate of changes in the coordinate to derive the possible displacement. Dual-frequency receiver was used in obtaining the coordinates difference with precision at several mm levels.

Compared between inclinometer data and of GPS measurements in monitoring landslides. And opined that the GPS stations were vital in detecting the potential landslide areas.

GPS Application in Tsunami Management

 In monitoring Tsunami, compared between GPS ground photos of damage areas and post-event satellite data. The photos of each damaged building were synchronized with high precision kinematic GPS for positioning. Damage buildings were identified with their intensity of damages such as partially or completely damage, partially collapsed with roof intact, and slightly damaged. They then compared post-event satellite image with ground truth GIS data and finally compared pre and post-disaster satellite image of the area and generated a tsunami damage map. The comparison they said helped in differentiating between the totally and partially collapsed buildings. While the GPS was helpful in determining the exact coordinates of the damage buildings within the area.

Used GPS to survey the Indian Ocean tsunami where they used a variety of standard field survey techniques. The measurement includes the Tsunami run-off height and local flow depth based on watermark and eye witnessed accounts. Each watermark was located using handheld GPS device and photographed. During the survey, maximum runoff inundation was determined relative to the sea level at tsunami impact with laser range finder and digital inclinometer and compass.

Application of GPS in Earth Quake

Integrated ground measurements and satellite remote sensing can help meet these various requirements for baseline and time-series data. GPS, for example, used for navigation and positioning in civilian and military applications, provides the millimeter-level differential accuracy that is used by regional ground deformation networks to monitor inter-seismic ground deformation and co-seismic displacement.

Using monitoring data from GPS stations in Taiwan, used GPS geodetic data to quantify the three-dimensional surface displacement pattern associated with the Chi-Chi earthquake. They demonstrated the co-seismic displacement of the Chi-Chi earthquake (Japan). The measurements were taken at pre and post-phases of the event generating a complete dataset for displacement studies.

GPS Application in Forest fire management

A study carried out by assessed the case of forest fire that gutted about 2,500 plus structures in the Oakland fire. Each of these structures was assessed with the aid of GPS and survey Questionnaire. The Global Positioning System was also invaluable in this phase for gathering locational information. During the Oakland fire, GPS and GIS were used to map the fire perimeter and georeference the location and number of each damaged or destroyed structure. This information was then overlaid with census data and existing parcel maps to assess individual losses to help support the process of applying for rebuilding loans and grants.

The overall application of GIS and GPS in the Oakland fire inspired a fire risk assessment study of other similar areas in California. An increase in adoption of geomantic technologies following disaster is a general trend. GPS has various ground based application in forest fire management ranging from preparedness to suppression processes.

Application of GPS in Flood Management

The utilization of Geomatic technologies i.e GPS, RS and GIS is being used increasingly for flood assessment, including the integration of inventory mapping, location of surface structures and roughness providing information on flow emplacement parameters (i.e. rate, velocity and rheology), and factors such as lithology, location of faults, slope, vegetation and land use. In managing a flood disaster, used GPS and Synthetic Aperture Radar (SAR) imageries to estimate flood water depth from SAR images. First of all, a land level map of Greater Dhaka was extracted from the DEM that consist four height classes. This land level map was used to collect representative ground truth data for each unit. Using a GPS, a total of 100 signatures (25 for each category) were collected and plotted on the land level map. Thus, a ground truth map was created and subsequently brought into GIS.

GPS coupling technology

The usability of GPS to disaster management does not only stop at the handheld level, GPS are usually mounted onboard other platforms in managing disaster. Utilized an Unmanned Aerial Vehicle (a digital imaging platform) for emergency response. The UAV has a collection of sensors (autopilots) that captures images coupled with GPS that provides the coordinates of different location as the UAV fly through the study site.

 The photos of each building were synchronized with high precision kinematic GPS for position. After locating the position of satellite images, comparison between the damage level in the ground photographs and high-resolution satellite data was made.

Advantage of gps in disaster management

One of the greatest advantage of GPS in disaster management is its ability to be used at any time of the day under any weather condition. Another advantage of GPS in disaster management is that GNSS has 100 per cent coverage of the planet GPS is free for all users, as such it can be used to manage disaster from anywhere in the world. GPS is used at every stage of a disaster event, right from the pre-disaster, during disaster and post-disaster events.

The wide range of applications of GPS in every disaster situation cannot be unconnected to the fact that it allows for easy integration with other geospatial technologies that aid in disaster management.

GPS limitation in disaster management

Like many other geomatic technologies, GPS also has certain limitations in its area of applications which disaster management is not an exception. Since GPS is mainly concerned with precise positioning, most of its limitation will not be unconnected to the degree of precision in finding locations. Consequently, these results to poor accuracy and low accuracies termed as “ERRORS” resulting from the satellite system, GPS receiver, atmospheric or environmental effects. Some of the GPS limitations include; GPS satellite signals are weak (when compared to, say, cellular phone signals), so it does not work well in indoors, underwater, under bridge and trees, etc.

The highest accuracy requires line-of-sight from the receiver to the satellite; this is why GPS does not work very well in an urban environment or under thick canopies. GPS accuracy is affected by certain sources of errors that could be from the satellite system, the atmosphere/environment or the satellite receiver itself.

Utilization of GPS technologies alone cannot be applicable in any disaster events needing comprehensive management except with the integration of other spatial technologies such as Remote Sensing data and GIS tools. The use of remote-sensing data with GIS offers high potential for vulnerability analysis of the interest region, although these techniques should be adapted according to the analyzed area.

The easy accessibility of the available geomatic technologies will in no small way have a great application in not only disaster management but also help in solving a wide range of man‟s problem and aid decision making. Today the use of orbital platforms is very efficient in preventing, monitoring and mitigating extreme disaster events.