Year after year, somewhere on Earth, natural or manmade disasters cause loss of life and widespread destruction, frequently spawning refugee situations. Though the risk of a disaster is low in any one particular place, earthquakes, volcanoes, floods, fires, landslides, oil spills, and hurricanes — when considered together on a global scale — regularly menace people, property, and natural resources.
Major disasters can temporarily make existing maps obsolete, rewriting river boundaries, shorelines, and land features in an instant. When disasters strike and first responders need to understand new situations on the ground, the best source of information often comes from the sky. Satellites, like Landsat, can tell responders what damage disasters have done, providing timely insight into flood extents, fire boundaries, lava flow directions, road conditions, and oil slick movements.
After devastating Hurricane Mitch swept through Central America in 1998 leaving 20,000 dead in its tracks, space agency leaders decided to take action and use their specialized resources to try to lessen the impact of future disasters.
In 1999, at the Third United Nations Conference on the Exploration and Peaceful Use of Outer Space (UNISPACE III) in Vienna, the European Space Agency (ESA) and the French space agency (CNES) proposed a system to supply free satellite imagery to emergency responders anywhere in the world. The outcome was the creation of the International Charter Space and Major Disasters; “Charter” for short.
You can think of the Charter as a one-stop-shop for impact maps — an essential resource, since in many cases satellite data are the only practical method to assess current ground conditions after a disaster.
Today, 15 space agencies that manage more than 30 satellites are part of the Charter, pooling their combined resources to ensure that spacefaring nations can quickly share their data for a humanitarian undertaking. Since its inception, the Charter has been activated more than 400 times.
While the U.S. was not originally part of the Charter, the National Oceanographic and Atmospheric Administration — with its mighty fleet of meteorological satellites —soon became a member in 2001. The U.S. Earth-observing satellite fleet, including Landsat, was not officially part of the Charter until the U.S. Geological Survey joined in 2005.
However, Landsat was used during the very first charter activation, in November 2000. After weeks of torrential rainfall, a small landside dammed up the Mangart Stream near the Italian border. The resulting pooled waters worked in tandem with the saturated slopes of Slovenia’s Mount Mangart to cause the mountainside to give way overnight. An estimated 1 million cubic meters (35 million cubic feet) of debris flowed into the Soca River, devastating a small village and killing seven people en route.
The Charter was activated a few days later. Thirteen satellite images were used, including two Landsat images taken before the disaster. All of the satellite images were gathered into a geographic information system (GIS) where the damage was analyzed. Using Landsat and SPOT imagery, a land use map was quickly created. This helped data analysts show responders that, although the majority of damage occurred in areas covered by deciduous forest, there was also significant damage in agricultural and inhabited areas.
In late 2004, a magnitude 9 earthquake triggered a devastating tsunami that affected Sumatra, Thailand, Sri Lanka, and southern India, killing more than 200,000 people. The Charter was activated three times to cover the large expanse of damage. Both-medium resolution data (Landsat, SPOT, Disaster Monitoring Constellation) and very high-resolution data (IKONOS, Quickbird) were used to map impacted areas and to calculate damage extent. This gave first responders an overview of the situation on the ground and provided them with information needed to plan relief logistics.
The U.S. Earth-Observation Fleet Joins the Charter
After the staggering devastation wrought by the Indian Ocean tsunami, Brenda Jones, a Disaster Response Coordinator with the U.S. Geological Survey, received an email from Charley Hickman, a USGS State liaison in Ohio. Hickman wanted to know why Landsat was not officially part of the Charter. Jones looked into the matter and quickly discovered that the Charter was keen to partner with USGS.
“The Charter was very interested in having USGS join because of Landsat,” Jones recounts.
Thus, in early 2005, USGS became an official participating agency of the Charter. While USGS had joined because of its Landsat resources, USGS membership brought a suite of other valuable satellite data to the Charter, including NASA’s MODIS, ASTER, EO-1, and even photos taken from the International Space Station. Additionally, commercial high-resolution vendors contribute their data through USGS.
Landsat’s combination of spatial and spectral resolution together with its 186-km (115-mile) image width makes its data particularly useful after hurricanes, fires, and volcanoes, and floods.
“It is very good for getting an overall extent of the disaster. It’s been very useful for the Charter,” Jones shared.
In late 2008, USGS made all Landsat data freely available, so anyone in the world could download data as soon as they reached the archive, usually within hours of acquisition. Since USGS runs the Landsat Mission Operations Center and it can task Landsat satellites to acquire data whenever they are over an affected area, its involvement in the Charter remains essential.
“Really, that’s one of the main reasons we are involved — to do the tasking,” Jones said.
This January, Landsat data were used when the Thames River flooded. A Landsat 8 image acquired on Jan. 7, 2014, was provided to the United Kingdom’s Environment Agency through the Charter. Kyle Brown, a Senior Geomatics Analyst with the agency, was the Charter project manager for the call.
“The flood data outline data were used at a local and national level to provide a strategic overview of the flooding and to help prioritize resources,” Brown explained.
Domestically, since USGS joined the Charter, Landsat data have been used to aid in damage assessments after Hurricanes Katrina and Rita ravaged the Gulf coast. Landsat imagery has also been used to map fire extents in the West, to map severe flooding in the Midwest, and to map the Gulf oil spill.
Although Landsat has been an important resource since the Charter began, its use has increased with USGS participation. “Since 2005, when USGS became a member, we have provided data for 149 activations,” Jones reports.
The Charter makes Landsat one more tool in a shared toolbox of space-based resources that can be used to provide first responders with the maps they need to help save lives around the world.