The Landsat satellite is used for a wide range of projects including comparing the effects of climate change to certain parts of the world. A team of researchers suggested that data from the Landsat satellite can also be used to locate shipwrecks in the various oceans across the globe.
Across the world's oceans, an estimated 3 million shipwrecks are scattered. These are usually found in areas close to shore where hazards of navigation such as reefs, rocks and vessel congestion are present. These shipwrecks may also pose serious danger to other ships passing by the area.
About a quarter of all these shipwrecks lie in the bottom of North Atlantic, an area that witnessed a lot of shipwrecks during the World War II. Submarines, mines and other submersibles attacked cargo ships travelling between Allied countries and Dutch or Belgian ports.
Since shipwrecks might pose negative environmental impacts, the Council of Europe's Parliamentary Assembly recommended that these should be mapped to be monitored.
Researchers used lidar, a device that uses light to measure distance, to help map regions of coasts in the past. They also used methods that use sounds like echosounders that are effective in deep water. These methods, however, involved too much expense making them not practical options.
The researchers at the Flemish Hydrography, Agency for Maritime and Coastal Services; Royal Belgian Institute of Natural Sciences; and Ulster University used data available from the NASA/USGS Landsat 8 satellite. This new method is cost-effective and practical in giving valuable data.
In the study published in the Journal of Archeological Science, the researchers came up with a survey of wreck sites in the coastal area off the Belgium port of Zeebrugge. They used data from a previous experiment using an echosounder survey of the region to detect four fully submerged shipwrecks. They used 21 Landsat 8 photos and combined them with tidal models. These were used to map the sediment plumes that extend from these wrecks.
The researchers believe that the study could be used in reverse to identify uncharted wrecks, with sediment plumes traced back to their sources. This cost-effective method paves way for scientists to map coastal regions without spending too much.
