Nacre, known as mother-of-pearl is a luminous and tough biomineral lining many seashells.
According to a new study, Nacre pearl holds an excellent record of ancient ocean temperature.
The claim was made in a study published in the journal Earth and Planetary Science Letters led by Professor Pupa Gilbert of the University of Wisconsin-Madison.
According to the team, the physical qualities of nacre in both old and new shells show the biomineral has an accurate record of temperature.
Importance Of Mollusk Origin
The claim of holding key idea on sea temperature has been pushed because the material is formed layer by layer in a mollusk.
"We can very accurately correlate nacre tablet thickness with temperature," says Gilbert.
The precise process has mollusks shedding their microscopic polygonal tablets of mineral aragonite and start donning the shiny biomineral that comes up as layers.
Meanwhile, Cornell University researchers threw more light on the process by which mollusks manufacture nacre.
Nanometer-scale resolution revealed that the organism builds nacre by depositing many layers of a material containing nanoparticles of calcium carbonate.
Thanks to nacre's ingenuity, scientists are getting an added advantage as a new way for measuring ancient ocean temperatures by sharpening methods used in other biominerals.
Meticulous Nano Process
Robert Hovden, a postdoctoral research associate at Cornell, and his colleagues gleaned an idea of the inner workings of a fan mussel called Pinna nobilis.
He said the mother of pearl is created by the consistent deposit of many layers of a material containing calcium carbonate nanoparticles. They move from inside to the outside of each layer by a fusion of flat crystals sandwiched by thin films of organic material.
The iridescence of nacre as a rainbow-like sheen comes from layers that scatter white light as soon as visible light hits the material.
Ocean Temperature Assessment
Meanwhile, an oceanographer at the University of Washington has proposed using internal tidal waves as a reliable and cost-effective method for assessing ocean temperature.
"We want to monitor global ocean warming, not just for tomorrow or next year, but for decades," said Zhongxiang Zhao.
Zhao's idea was an innovation of the idea pushed in the 1970s by Walter Munk, who proposed acoustic tomography in assessing ocean's temperature. As sound travels faster in warmer water, measuring the time for an acoustic pulse in traveling across the ocean was mooted by the expert.
However, the outcry that sonar blasts will harm marine mammals, led to the scrapping of the experiment in 2006.
Zhao's new method improvises on the early idea and calls for monitoring the travel time of internal tidal waves.
