European Union satellite data will assist in tsunami reconstruction efforts and help settle land disputes, writes Dick Ahlstrom.
Indonesia and Sri Lanka have asked the EU to assist reconstruction of regions devastated by the Indian Ocean tsunami using satellite imagery. The data will help affected citizens prove property ownership in areas scoured clean by the incoming waves.
The EU's largest Directorate-General, the Joint Research Centre in Ispra, Italy, has for some years provided emergency satellite imagery to help cope with natural disasters, says Dr Jean Paul Malingreau, JRC head of unit who helps put together the Centre's work programme. "We did this in the past for forest fires in southern Europe and floods in Germany," he says.
As part of the JRC's world satellite data programme, Ispra also holds images that provide a view of the planet's entire land mass, data that proved very important immediately after the December 26th earthquake and its resultant tsunami.
"On the 27th I called the head of the unit in Ispra in charge of global security aspects of the programme," says Malingreau. He was also in touch with a senior colleague who, coincidentally, was travelling in the mountains of Sri Lanka.
All agreed that the JRC should begin providing quick data on the impact of the tsunami with before-and-after imagery using data from a variety of satellites.
"That information is based on data we have in the archive on coastlines, vegetation and land use," Malingreau says.
The havoc brought about by the tsunami was on an entirely different scale than previous disasters, however. "We were facing an enormous challenge," says Malingreau.
In the days immediately after the tsunami, the JRC provided before and after satellite imagery for damage to a land mass about two km wide and 8,000 km long, "a very narrow strip of land along a very long coastline. It was a scenario that didn't exist previously. The data had to cover all the way from Africa and Somalia across to Sumatra," he says.
It worked in cooperation with the United Nations Office for the Coordination of Humanitarian Affairs. "We also provided information to ECHO, the humanitarian aid agency of the Commission," Malingreau says. "The issue was how to collect and put together in a meaningful way all the information needed by the relief programme."
The satellite data helped in two ways, providing low-resolution images that showed gross impacts such as alteration to forest cover, the affects on urban areas and coastal changes. The fine detail of regional impacts was shown using one-metre resolution images able to pinpoint damage in much greater detail.
Now the JRC role is to change following a request for assistance from Indonesia and Sri Lanka. It will provide before and after high-resolution imagery as a way to assist in the reconstruction of private properties and public buildings in Banda Aceh and Meulaboh in northern Sumatra and in Sri Lanka's affected areas.
The agreement, to be announced by the Commission in the coming days, will enable property-owners to prove where their houses stood. So complete was the damage done to these regions that not only houses but many foundations were swept away or displaced. Affected citizens might not be able to prove where their properties were located, given many holdings do not have documented recognition of land rights.
The JRC is to combine existing land survey and land registry data with pre- and post-tsunami satellite mapping. With one-metre resolution, the satellite images will easily be able to pick out property lines and structures that disappeared after the tsunami.
"This data, along with the pre-tsunami satellite mapping, when eventually placed against post-tsunami satellite imagery, would allow for the necessary adjustments of land and property demarcation in the affected areas so that reconstruction can commence as soon as possible," according to a source in the JRC. Land rights will be protected and rebuilding will get under way faster, the source suggests.
In effect, the JRC will be building a new form of electronic map that it refers to as "spatial data infrastructures". These new maps are constructed using ground positioning systems, remote satellite sensing and geographic information systems.
Having this blend of data is invaluable in the context of disaster recovery, Malingreau suggests. Being able to compare before and after imagery allows relief planners to "weigh" impacts in various regions so that those most in need of aid are included in the earliest response.
The question to be answered is "How do you make sure that you address the areas that need help first? The second thing is you refine the analysis and assess the actual damage," Malingreau says.
The satellite imagery allows the planners to see which bridges and other infrastructure are lost, how much housing has been destroyed and how agriculture in a region has been damaged. This information tells the planners what kind of resources have been hit and also provides a template for reconstruction.
This approach can provide information even when little or none is available on the ground. The authorities in Myanmar or Burma provided very little information about impacts along their coastline immediately after the tsunami and also declared very low death rates.
Yet the early satellite data provided by the JRC clearly showed that the waves had caused widespread damage to coastal areas. Luckily most of the coastlines affected had few large urban areas.
What is ultimately required is some form of integrated system that provides early warning of impending disasters following earthquakes or volcanoes, and then delivers useable on-the-ground information to relief workers seeking to respond to emergencies, Malingreau believes.
The JRC runs a "Global Disaster Alert System" that can pick up seismic events. This system let Ispra scientists pinpoint and measure the Sumatran earthquake within 90 minutes of the event. "We have automatic alert systems linked to seismic events, but there is no tsunami information available in the region," says Malingreau.
"There are early warning systems that exist and can be put in place in the Indian Ocean. Technically this type of alarm system can be put together. The problem is how do you get the information down to the people on the beach."
Further information from: www.jrc. cec.eu.int