A team from the University of Sydney has created the first topographic map of the ocean in 40 years. The last one, made in the 1970s, was hand drawn, while this is the first digital map of the ocean floor, and it contains some pretty interesting things. For one, the ocean floor, especially the Southern Ocean around Australia, is more complex than we realized. Deep basins in the ocean floor, as it turns out, are much more intricate than previously imagined.
Mapping the ocean floor can tell us a lot more about the ocean, which covers 70% of the Earth. It’s especially useful in teaching us how it has adapted to climate change throughout the Earth’s history.
For example, much of the ocean floor is actually made of the fossilized remains of phytoplankton. Phytoplanktons are microscopic creatures that thrive in sunlight, not unlike plants. In fact, phytoplankton process so much CO2 that they create about 25% of the oxygen we breath, and contribute more to controlling climate change than terrestrial forests.
When those phytoplankton die they sink to the bottom of the ocean, and retain the CO2 they had breathed in when they died. That CO2 isn’t released into the surrounding ocean, which is good because when it dissolves in seawater it becomes carbonic acid and the oceans are already rapidly becoming more acidic.
Interestingly, the accumulations of dead phytoplankton don’t match up with the locations of phytoplankton blooms on the surface of the water. So we understand where they tend to live, but we don’t yet understand the process by which they sink. Understanding that process will require more research, and that research is important.
Understanding how phytoplankton live, and how they die, could help us to better understand how oceans adapt to climate change, a task researchers will have earnestly pursue in the coming years. A deeper understanding might even help us find a way to combat climate change.