Cook Islands seabed secrets mapped

NIWA scientists and Toitū Te Whenua Land Information New Zealand (LINZ) have used satellite technology to chart the Cook Islands’ seafloor in never-before-seen detail. The work is part of Seabed 2030, a collaborative project to produce a definitive map of the world ocean floor by 2030.

The chart of Suwarrow and Pukupuka in the Cook Islands builds upon decades-old surveys, with more accurate positioning and wider coverage, including information on harder to reach areas such as shallow lagoons.Kevin Mackay, a Researcher of Marine Geology at NIWA, heads the Seabed 2030 South and West Pacific Ocean Data Centre, one of four global Regional Centres, each responsible for data gathering and mapping in their territory. He says that using satellites has seen a paradigm shift in the way we measure sea floor.

"To measure the depth of the ocean, you would traditionally have to send out a boat with an echo sounder, which costs a lot of money and can be dangerous. With satellites, we can access extremely remote locations, with less carbon footprint, and we don’t have to put people in harm’s way."
The images are taken from two commercially owned satellites, World-View-2 and GeoEye-1, which provide extremely high-resolution pictures of the earth’s surface.
The software needs to get rid of shadows, waves etc so, it strips away the water and uses complex algorithms to produce depth estimations, then creates a map with colourings of what the seafloor would look like without any water, which we can then use..
Seabed 2030 is a collaborative project between The Nippon Foundation and GEBCO. The South and West Pacific Ocean Regional Centre is made up of NIWA, GNS Science and LINZ working together to map over 123 million km 2 of ocean. Currently, less than 20% of the world’s seafloor is mapped.
The nautical chart has just been published.