The modern global oceans average temperature is 3.5 degrees Celsius, say scientists who have found a “ground-breaking” approach to measure the average temperature of the ocean.
Determining changes in the average temperature of the entire worlds ocean has proven to be a nearly impossible task due to the distribution of different water masses, researchers said.
Each layer of water can have drastically different temperatures, so determining the average over the entirety of the oceans surface and depths presents a challenge, they said.
Now, researchers at the University of California San Diego in the US have been able to bypass these obstacles by determining the value indirectly.
Instead of measuring water temperature, they determined the ratio of noble gases in the atmosphere, which are in direct relation to the oceans temperature.
“This method is a radically new way to measure change in total ocean heat,” said Jeff Severinghaus, a geoscientist at University of California San Diego.
“It takes advantage of the fact that the atmosphere is well-mixed, so a single measurement anywhere in the world can give you the answer,” said Severinghaus.
In the study published in the journal Nature, the scientists measured values of the noble gases argon, krypton, and xenon in air bubbles captured inside ice in Antarctica.
As the oceans warm, krypton and xenon are released into the atmosphere in known quantities.