Ancient Sea Sponges: New Study Suggests Global Warming is Deepening

Scientists are studying ancient sea sponges that are at the center of a bold claim that global warming has already reached 1.7 degrees Celsius.

The sea sponges are found between 30 meters and 90 meters below the surface of the Caribbean Sea. It is a species that grows a hard skeleton and has been quietly recording changes in the ocean's temperatures for hundreds of years.

Deepening Global Warming

(Photo : Charly TRIBALLEAU / AFP) (CHARLY TRIBALLEAU/AFP via Getty Images)
Scientists used data taken from analysis of ancient sea sponge to suggest that global warming is actually worse than previously estimated.

The claim argues that since the start of the Industrial Revolution, the planet may have already reached a warming of 1.7 degrees Celsius. This is half a degree more than previous estimates that were used by the United Nations climate panel.

Several leading scientists, however, have urged caution amid the new suggestions, saying that the latest research had "overreached." They also questioned whether such a bold claim could be made based on one sponge species from a single location.

However, the one who led the latest research, Professor Malcolm McCulloch of the University of Western Australia, said that the results were robust. The team published their findings in the journal Nature Climate Change, as per The Guardian.

McCulloch said that their findings, taking the precautionary principle, show that global warming is more advanced than previously thought. This means that the latest findings are a wake-up call for the need to reduce carbon dioxide.

He added that people will experience more serious impacts of global warming sooner than previously anticipated. Researchers, with the help of deep-sea divers, removed six specimens of Ceratoporella nicholsoni from areas off the coast of Puerto Rico and the U.S. Virgin Islands.

These are a type of sponge that can take hundreds of years to grow between 10 centimeters and 15 centimeters. As they grow, they store strontium and calcium in a ratio that relates directly to the temperature of the water around them.

McCulloch argued that the big picture is that the global warming clock for emissions reductions to minimize the risk of catastrophic climate changes is being pushed forward by at least a decade, according to EuroNewsGreen.

Hotter Than Previously Anticipated

Scientists have noted in the past several years more extreme and harmful weather, including floods, storms, droughts, and heat waves, than they had expected for the current level of warming.

The co-author of the recent study, Amos Winter, said that one explanation for this is that there was more warming than scientists had initially calculated. The paleo oceanographer at Indiana State University said that the latest research also supports the theory that climate change is accelerating, which was proposed last year by former NASA top scientist James Hansen.

The team's findings add to other evidence that suggests that societies started warming the Earth earlier than 19th-century temperature records indicate. Scientists and governments still use those older records as the benchmark for measuring total warming.

This is largely due to practical reasons and even if they are not perfect, they are a yardstick that everyone can more or less agree on. This is why several researchers who were not involved in the latest study expressed hesitation about trusting the ancient sea sponge data, said the New York Times.