High resolution maps of the planet’s lesser known surfaces

It is absurd to think that we have more information on Mars and Moon’s surfaces than on our oceans, yet it is so. Currently, the maps of the oceans only cover 19% of their surface, at the beginning of 2017 the mapped area was even 6%. Starting from this last figure, the Nippon Foundation and the General Bathymetric Chart of the Oceans (GEBCO) launched a project in 2017 aimed at collecting and putting together all possible bathymetric data to create a complete map of the ocean floor by 2030.

Seabed 2030, that is the name of the project, promises a high-resolution cartography (we are talking of a 100-m-resolution) that uses echosounders, which are instruments that measure the depth of the sea through sound waves. Echosounders are fixed on the keels of the ships, from where they spread the sound waves in several directions. The time interval between the emission and the moment they return is recorded and then divided by two. This provides a measure of the depth of the water. Thanks to computers, the echosounder readings allow a three-dimensional reproduction of the seabed and, from the data collected, it is also possible to know what type of rocks they are made of.

Needless to say, a huge project like this takes a lot of time and many ships. That is why the oceans have been divided into four parts, each of which is then mapped by one or more institutions involved. Among these is Ocean Infinity, an American marine robotics company. Its contribution will be essential to achieve the goal. Ocean is in fact building a fleet of robotic ships, called the Armada. It will be precisely thanks to these cheap and unmanned ships that it will be possible to map even the most isolated areas of the oceans, and therefore cover the entire ocean surface by 2030.

Why can it be such a game changer to have a complete cartography of the oceans?

First of all, a well-defined map would help us to better understand the dynamics of phenomena such as tsunamis, tides and sea level rise, therefore of climate change, thus allowing us to make more accurate predictions on the phenomena trend over the years. Furthermore, the presence of a complete mapping will also simplify the control of subsea pipelines for the disposal of optical-fiber and gas cables.

Despite the challenges posed by covid-19, the project did not stop and continued to map the oceans. On 21 June 2020, on World Hydrography Day, Seabed 2030 announced that the mapped area was 13% larger than it was when the initiative was launched. Project Director Jamie McMichael-Phillips said that “over the next year, we anticipate similar levels of data contributions through donations of archive material and, as COVID restrictions abate, new data from surveys, ships transits and crowd sourcing”.