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The mystery of climate change is solved

The mystery of climate change is solved

Scientists have solved one of the main mysteries of climate change, showing that the annual global temperature today is the warmest of the last 10,000 years. This is according to a study conducted by Rutgers University, published in the journal Nature.

Researchers say their findings challenge long-held views on the history of Holocene-era temperatures that began some 12,000 years ago. "Our reconstruction of events shows that the first half of the Holocene was colder than in the industrial age, due to the cooling effects of debris from previous glaciers," said study lead author Samanta Bova.

"The late warming during the Holocene was actually caused by an increase in greenhouse gases in the atmosphere, as predicted by climate models. "This eliminates doubts about the key role of carbon dioxide in global warming."

The scientists, funded in their study by the US National Science Foundation, used marine limestone (which contains calcium carbonate), foraminifera fossils - single-celled organisms that live on the surface of the ocean - to reconstruct the history of temperatures in 2 more intervals. the end of the warm climate on Earth.

They are the last interglacial period, from 115,000 to 128,000 years ago, and the Holocene Age. To obtain the fossils, scientists collected a core of bottom sediment near the Sepik River estuary near Papua New Guinea during Expedition 363 of the International Ocean Exploration Program.

Sediments enabled researchers to recreate the history of temperature in the warm waters of the Western Pacific, which closely follows changes in global temperatures. How temperatures evolved during the last interglacial epochs and the Holocene Age is something debatable.

Some data suggest that the average annual global temperature during modern times does not exceed the warmth that existed in the early Holocene warm period, called the "Holocene thermal maximum," which was followed by global cooling.

But climate models strongly suggest that global temperatures have risen over the past 10,000 years. The scientists found that in fact post-industrial heating, has accelerated the long and steady heat trend throughout that time period.

"The tools we use to understand the climates of the past contain a wealth of information. "These results show that the climate of the industrial age and global temperature trends are even more different from the natural trends of the past," said Kendis Mejger, chief of the National Science Foundation's Ocean Science Division. / NSF - Bota.al