The blog of Xeno, a slightly mad scientist
Massive reserves of “freshwater” are buried beneath the seabed on continental shelves around the world, including off Australia, China, North America and South Africa.This is the conclusion of a new study by a team of Australian scientists that appears in this week’s issue of the journal, Nature.Based on an analysis of seafloor water studies conducted for oil and gas exploration purposes, the study showed that an estimated that 500,000 cubic kilometers of low-salinity water is trapped in aquifers under the ocean floor.“The volume of this water resource is a hundred times greater than the amount we’ve extracted from the Earth’s sub-surface in the past century since 1900,” said Vincent Post, a groundwater hydro geologist from Flinders University in Adelaide and the new study’s lead author.This new freshwater resource could give regions suffering with limited access to freshwater more options for combating the impact of droughts and alleviating the impact of water scarcity on future generations.By 2030, nearly 50% of the planet’s population will exist under
conditions of high water stress, according to the United Nations.The new study undercuts the conventional wisdom on undersea freshwater reserves, which until now were considered to be rare.“By combining all this information we’ve demonstrated that the freshwater below the seafloor is a common finding, and not some anomaly that only occurs under very special circumstances,” said Post.
“The volume of this water resource is a hundred times greater than the amount we’ve extracted from the Earth’s sub-surface in the past century since 1900,” Post said in a statement. “Knowing about these reserves is great news because this volume of water could sustain some regions for decades.”
While he said that groundwater scientists were aware that there was freshwater located beneath the ocean seafloor, they believed that it only happened in a handful of places and only under special conditions. However, their new research has revealed that these types of aquifers “are actually quite a common phenomenon.”
According to Forbes contributor William Pentland, the United Nations warns that nearly half of the global population will live under
conditions of high water stress by the year 2030. Post’s team’s findings could help delay that looming water crisis, while also providing potential relief for drought-stricken regions.
The discovery was the result of a review of seafloor water studies conducted for scientific or petroleum exploration purposes, Post told AFP. The newly-discovered freshwater deposits were reportedly formed over hundreds of thousands of years, during a time where lower sea levels meant that the regions that are now under the ocean had been exposed to precipitation. That rain would have been absorbed into the underlying water table.
“Freshwater under the seabed is much less salty than seawater,” he said. “This means it can be converted to drinking water with less energy than seawater desalination, and it would also leave us with a lot less hyper-saline water.”
“Freshwater on our planet is increasingly under stress and strain so the discovery of significant new stores off the coast is very exciting. It means that more options can be considered to help reduce the impact of droughts and continental water shortages,” Post continued, adding that it was now important to care for the seabed. “For example, where low-salinity groundwater below the sea is likely to exist, we should take care to not contaminate it.” …
Is fresh water still the new oil?