The remoteness and economic deficiencies of many corners of the world have historically resulted in a lack of good maps. One side effect of having poor maps is a certain slowness to respond to natural disasters: without accurate views of local vegetation, road networks and medical facilities, relief workers have difficulty locating and navigating disaster-impacted areas, or even determining the extent of damage.
When an event such as the Indian Ocean tsunami wipes out entire communities, shattering communications lines and obliterating roads, it completely cuts off access by the rest of the world – a type of destruction that no line-drawn maps could ever illustrate.
After the tsunami, high-resolution satellite imagery became a remarkable tool for helping the world understand the devastation that had occurred. At 60-centimeter resolution, these images depict enough detail to count individual trees and buildings.
Images were collected of the southwestern coast of Sri Lanka on Dec. 26, slightly less than four hours after the 6:28 a.m. earthquake and shortly after the moment of tsunami impact. Showing churning ocean waters and high water at least a kilometer inland, they offered some of the first glimpses of destruction. Two days later, images were collected of Banda Aceh, Indonesia, where unthinkable damage and death tolls resulted. They showed a markedly changed shoreline, flood damage more than three kilometers inland, large piles of debris and destroyed villages.
Two medical doctors associated with the Visualization Center at San Diego State University traveled to Indonesia to work with the U.S. military, NGOs and the United Nations on relief efforts. Using before-and-after satellite imagery and 3D fly-throughs placed on a secure server and laptops equipped with Global Positioning Satellite receivers, the workers assisted the relief community in assessing damage and determining where to safely build refugee camps, medical facilities, communications networks and transportation routes.
Eric Frost, co-director of the Visualization Center, said, “The images showed that the damage was seriously much worse than anyone first thought. They motivated people to take action and send relief right away. They were also invaluable for working with city and village leaders on some ultra-fast urban planning efforts.”
The advent of high-resolution satellites now makes it possible to obtain digital views of the most remote corners of the world, offering disaster response teams a useful tool for recovery and mitigation efforts well into the future.