Geospatial Data For Disaster Management

A series of devastating floods in China during July-November 1931 was one of the most lethal natural disaster of 20th century. Estimates of the total death toll range between 1,000,000–4,000,000.

The Great Peruvian earthquake occurred on 31 May 1970 off the coast of Peru in the Pacific Ocean is among the most catastrophic natural disaster. It estimated 66,794 to 70,000 casualties.

The Bengal famine of 1943 was a major famine in the Bengal province in British India during World War II. An estimated 2.1–3 million, out of a population of 60.3 million, died of starvation, malaria and other diseases.

What are Natural Disasters?

History created when nature shows its cruel face. This happened various times In the history of human civilization. Yes we are talking about the natural disasters.  They are sudden and unexpected. Environmental, financial and human loss caused by these sudden and unexpected events are called natural disasters. Avalanches, blizzards, drought, earthquakes, famine , extreme heat or cold, hurricanes, landslides, tornadoes, volcano eruptions, and wildfires are main events under this definition.

Root Causes

'Be prepared' is the only thing we can do about this. We can't predict them with 100% accuracy and we can't avoid them as well. So we can just be prepared for them. Preparation depend on how well we know the fundamental cause of these events. More we know the root causes better will be the preparation.

social Root Causes:

“only human beings can recognise catastrophes, provided they survive them; nature recognises no catastrophes.” – Max Frisch.

Human activities play a vital role in the frequency and severity of disasters. Recent flood of Kerala in India is a best example of how human activities are disturbing the balance of nature. Once the state was full of green forests and paddy farms but with due course of time urbanization happened and lot of deforestation took place. Vegetation help slow runoff and prevent flooding. When there is a lack of vegetation, however, there is little to stop water from running off.

Movement of Earth:

There are various activities that happened deep inside the earth. These movements occur with the minimum amount of warning and include earthquakes, volcanic eruptions and tsunamis. They are difficult to predict and impossible to stop. All that can be done is to take appropriate action to limit damage and loss of life after they occur.

Weather:

Extreme weather conditions are responsible for some natural disasters like hurricanes, tornadoes, extreme heat and extreme cold weather. Huge storms, hurricanes thunder across the warm oceans of the world such as the Atlantic, the Gulf of Mexico, the Caribbean, and the Western Pacific Ocean (where they are called typhoons), up to higher latitudes.

Natural Disasters And Their Management using Geospatial  Technology

Every aspect of a disaster is referenced by location and when it comes to locate places accurately, geospatial is the most precise modern day technology. A survey reveals that more than 80% of disaster management practitioners are using geospatial technology. Following are the points illustrating how this technology is playing a key role in disaster management.

 
A) Situational Awareness

GIS and remote sensing plays vital role to provide location information of the event, that is, where is the event happened and what is happening exactly in real time. Satellite imageries and UAVs (Drones) are capable of providing latest real time imageries which are helpful in decision making. High resolution and ultra high resolution imageries are used for in-depth analyse of the affected area. 

B) Planning and Analysis

Planning and analysis are the two most important aspects that laid foundation for decision and policy making. GIS is a complete information system for modelling, analyzing spatial data and displaying community vulnerability.GIS data is useful for the identification and marking of the potential zones for such activities. Experts analyse this data and suggest some robust emergency planning's accordingly.GIS and remote sensing data provide details about pattern of events, density of population, kind of terrain present and all the routes which can be used during evacuation plan.

C) Preparedness

Once the areas prone to such events are identified we need to make a strong mitigation plan. Preparation involve those activities which are carried out during actual emergencies. GIS data is used as an input for preparation. One should know some basic and most important figures like how many paramedic and logistics unit are required and where should they be located. GIS provide a real-time monitoring like reservoir level at dam sights and radiation monitoring at some nuclear or thermal plants.

D) Response

This is the most critical phase of disaster management. Data is immediately required to decision makers about scope of damage and to identify locations where people may be trapped or injured or require medical support and rescue. At the same time geospatial data can provide situation of critical infrastructures restoring vital services that are or could be damaged.

E) Recovery

GPS is used to locate damaged facilities, identify the type and amount of damage and establish priorities for action. During this phase GIS is involved for a long time for major restoration.

Summary

Environmental, financial and human loss caused by sudden and unexpected events is called natural disaster. Avalanches, blizzards, drought, earthquakes, famine are some examples. Human activities play a vital role in the frequency and severity of disasters. There are various activities that happened deep inside the earth. These movements occur with the minimum amount of warning and include earthquakes, volcanic eruptions and tsunamis. They are difficult to predict and impossible to stop. GIS and remote sensing plays vital role in Situational awareness, Planning and Analysis, Preparedness, Response, and Recovery.