PDC Updates | May 17, 2010
Vietnam Provinces
If what you need to know is only which Vietnam province is where, this map would do the job. However, if you were looking for trails to hike, highways to drive, cities to stay in or rivers to navigate, you’d need something quite different. Similarly, disaster managers have very different needs when they are planning for community resilience, preparing for a possible disaster, responding to various hazard events, or trying to return a community or a country to non-emergency operations after a catastrophe. That is where geographic information systems, GIS-based maps—and PDC—come in.
A lot of the work done at PDC results either in creating maps or producing new layers to incorporate into mapping systems. The new layer might be about population density, evacuation routes and shelters, characteristics that would make the people in various areas differently vulnerable to hazards, or it may visualize a specific historic or real-time threat like a tsunami or a tropical cyclone, for instance. In fact, the possibilities are genuinely endless, as new needs are met every day in the constant effort to provide everyone from first-responders to heads of state with more accurate, faster, more detailed and more easily used solutions in the form of geographic information systems (GIS) maps and products.

Spatial information products and maps can be effective tools for assessing and communicating conditions during all phases of disaster management. A well-designed map can provide a disaster manager with the information necessary to make quick, well informed decisions that save lives. Conversely, a poorly designed map can be misleading and add to confusion before, during, and after a disaster, which is why GIS and all geospatial technologies require trained experts to turn often-massive amounts of raw data and model outputs into instantly comprehensible maps, visualizations and models. Disaster managers at all levels have to become familiar with the general concepts of maps and cartography (map making), and to know a variety of map types and map uses. They must also have the skills to successfully use maps and geospatial data for decision making or advising decision makers.

Maps are important tools that are used by disaster managers for:

  • Recording and storing information
  • Discovering and analyzing spatial patterns and relationships
  • Conveying information that is difficult to express verbally
  • Visualizing complicated textual data
  • Expressing patterns or trends over time
  • Navigating by sea, air and land
  • Assisting in decision making

So, how can a map save your life?

Maps of hazards, populations, assets and resources and their characteristics support activities in all phases of disaster management. Maps can illustrate the types of hazards that may occur in a particular place, and indicate the likelihood of each. Maps can help disaster managers identify areas most likely to be impacted by hazard events, as well as the real-world features (people, hospitals, crops, etc.) that might be affected. GIS and mapping can assist in locating areas where disaster impacts are most likely to be severe based on the characteristics of both the hazards and the assets/populations exposed. Disaster managers can use maps to target appropriate structural and non-structural mitigation measures, develop more effective strategies for warning and evacuation, and better anticipate and plan for the types of impacts that might occur. When an event occurs, disaster managers can use existing maps to determine initial responses and priorities. As information comes in, GIS tools allow disaster managers to update maps and provide what is called a "common operating picture" of damage and needs.

Mapping things such as likely impacts to communities, the environment and public facilities serves disaster managers both in their day-to-day work and in emergency conditions. It is not that the data in the map would not be available if it were not mapped. One of the otherwise insurmountable problems solved by mapping is not so obvious, but it is easily understood: There may thick books and recent reports, huge tables of longitudes and latitudes or census data filling many shelves in an Emergency Operations Center, and the facts are often in there—somewhere. With a well designed map, the facts are all in one place, visualized in ways that can be grasped instantly, manipulated as the situation changes, shared on screen or by way of the Internet. In an emergency, while information that has to be researched and calculated may be useless because of time constraints and other factors, information that can be understood at a glance is priceless. That’s what GIS-based mapping provides.

To learn more about how disaster managers might use maps, spend some time with the PDC Hazards and Vulnerabilities Atlas. It will allow you to display, then hide various layers of hazard information, observations and forecasts, population, infrastructure (e.g., roads and hospitals), etc. It also has the familiar political boundaries and photograph-like aerial views.

Here are some other web-based resources that will help you understand GIS and disaster management maps:

  • A professional paper about PDC’s application of GIS and Modeling to dengue fever in Hawaii
  • A fact sheet on PDC using geospatial technologies in the field to help Pacific island nations
  • An explanation of PDC impact modeling with regard to dam-break scenarios
  • The American Samoa mitigation-plan project done by PDC
  • The GIS project that created The Hawaii County Remote Information Services (RIS)
  • "Hazard Maps Help Save Lives and Property" by the U.S. Geological Survey (USGS)
  • "Open Source Maps Are Helping The World Bank Save Lives in Haiti" on Fast Company
  • "How Satellites Save Lives" by contributing to real-time mapping in The Independent
  • For more PDC resources, search "GIS" on the home page at www.pdc.org
Some links may become inactive over time. If you find a broken or inoperative link to an external resource, you may want to search at that resource for the relevant information. If you find that a link referring to a pdc.org page fails, please inform the PDC Webmaster.