Oceans Get Their Volume and Depth Calculated

In a research of unprecedented level, experts at the Woods Hold Oceanographic Institution (WHOI) managed to calculate the answer to two of the most basic questions about out planet – how deep the ocean is, and how much water it contains. When talking about the atmosphere, scientists have a fairly advanced understanding of where the various layers begin and end, and how large each of them is. The opposite is not true. When it comes to studying oceans, researchers admit that the difficulties associated with exploring it have made the field stagnate for some time now, e! Science News reports.

“A lot of water values are taken for granted. If you want to know the water volume on the planet, you Google it and you get five different numbers, most of them 30- or 40-year-old values,” explains WHOI Department of Marine Chemistry and Geochemistry associate scientist Matther Charette. He was a part of the team that managed to precisely calculate that the approximate amount of water contained in the planet's oceans is 1.332 billion cubic kilometers. The work was conducted in cooperation with a group of scientists from the US National Oceanic and Atmospheric Administration (NOAA) National Environmental Satellite, Data and Information Service (NESDIS), led by co-study investigator Walter H.F. Smith.

The two say that their investigation was informed by a wealth of satellite-collected datasets, which were all centralized in order to obtain the new figure. Full details of their work appear in the latest issue of the highly-regarded scientific journal Oceanography. One interesting thing the group notes is the fact that the bottoms of oceans “are bumpier and more mountainous than had been imagined,” according to Smith. This led to the new assessments of the total volume of water being 0.3 percent lower than the one estimated some three decades ago. In practical terms, this translates into five times the volume of water in the Gulf of Mexico missing, or the equivalent of 500 times the water of the Great Lakes.

Smith adds that satellite data are not the most accurate way to measure such data. He reveals that ship-based studies could be more suitable for this type of investigation. “There is a problem of spatial resolution, like an out-of-focus camera. We're measuring the sea surface that is affected by mountains, but we're seeing only really big mountains, and in a blurry way. The resolution is 15 times worse than our maps of Mars and the Moon,” he concludes. Saving the best for last, the mean depth of the world's oceans has been calculated to be 3,682.2 meters, or 12,080.7 feet.