“More than 80 percent of the ocean remains unobserved. A landmark 2025 study in Science Advances revealed that only 0.001 percent of the deep seafloor has ever been visually surveyed. That amounts to an observed area roughly the size of Rhode Island, despite the deep ocean covering two-thirds of our planet,” notes Aditya Goyal.
Science explains:
Despite the importance of visual observation in the ocean, we have imaged a minuscule fraction of the deep seafloor. Sixty-six percent of the entire planet is deep ocean (≥200 m), and our data show that we have visually observed less than 0.001%, a total area approximately a tenth of the size of Belgium. Data gathered from approximately 44,000 deep-sea dives indicate that we have also seen an incredibly biased sample. Sixty-five percent of all in situ visual seafloor observations in our dataset were within 200 miles of only three countries: the United States, Japan, and New Zealand. Ninety-seven percent of all dives we compiled have been conducted by just five countries: the United States, Japan, New Zealand, France, and Germany. This small and biased sample is problematic when attempting to characterize, understand, and manage a global ocean.
Scientists discovered more than a hundred new species in the sea east of New Zealand.
The world’s coral reefs are more plentiful than previously thought. “High-resolution satellite maps show that coral reefs cover an area of ocean larger than New Mexico,” reported Bloomberg News. That’s about twice the size of some prior estimates.
A rare bus-sized jellyfish was recently spotted in the deep sea.
There are still many things to discover, and many unknown facts. “More than 3 billion people rely on water whose quality is completely unknown due to a lack of monitoring,” and “Sub-Saharan Africa has just one air quality monitor per 15.9 million people, compared to roughly one per 100,000 in Europe.
