TCarta advances coastal safety with satellite data
Recent incidents involving naval and commercial vessels running aground have underscored the inherent risks of maritime operations in shallow or poorly charted coastal waters. As these occurrences off the coasts of Oman, Greenland and Fiji continue to be investigated, it is becoming clear that the underlying causes are often complex. However, a common thread is the lack of up-to-date bathymetric data in many coastal areas, particularly those outside established shipping lanes. This gap in accurate mapping can significantly heighten the risk of such accidents.
TCarta Marine, based in Denver, offers a modern solution to this problem. By utilizing Earth observation satellites, it provides accurate water depth measurements for nearshore areas – a method that is both cost effective and environmentally friendly. “The risk of such accidents can be significantly reduced with up-to-date bathymetric data produced from satellite imagery,” explains TCarta president Kyle Goodrich. He notes that, in many coastal regions, the waters beyond commercial shipping lanes are often either poorly charted or completely unsurveyed.
Traditionally, gathering high-quality depth measurements in these shallow coastal areas has been an expensive and hazardous task, typically involving ships or aircraft. This challenge is especially pronounced in remote or contested regions, where access can be difficult. Goodrich emphasizes that “the risk of groundings is only growing as military vessels and ecotourism charters increasingly operate in unfamiliar and inadequately mapped coastal zones.”
Benefits of SDB
For over a decade, TCarta has been addressing this need by supplying marine charting organizations with water depth data through a technique known as satellite derived bathymetry (SDB). This approach relies on physics-based algorithms applied to optical imagery captured by commercial satellites. By detecting and measuring the light that reflects off the seafloor, SDB calculates water depths with impressive accuracy, reaching depths of 20 to 30 metres depending on water clarity.
One of the standout benefits of SDB is its safety and efficiency. Goodrich highlights that “in addition to posing no danger to personnel, equipment or coastal environments, satellites are more cost effective than shipborne sonar or airborne laser scanning because they acquire image data over large regions in seconds.” Moreover, satellites have the advantage of operating without geographic constraints, allowing data collection in areas that might be inaccessible to vessels or aircraft.
Over the years, TCarta has mapped nearly a third of the world’s coastlines using SDB. It offers both custom and ready-made bathymetric products. Custom datasets leverage high-resolution satellite imagery to achieve a one-metre resolution, capable of detailing features such as shoals and reefs. Meanwhile, its off-the-shelf solution, global satellite derived bathymetry (G-SDB), provides ten-metre detail, making it ideal for detecting coastal shoals in remote areas that often remain uncharted. This product is readily available for numerous key locations, including the South China Sea, Arabian/Persian Gulf, Gulf of Oman, Red Sea, Black Sea and the eastern Mediterranean.