Climatologists have found that now the climate on Earth is changing faster than 24 thousand years ago, during the last glacier attack on Eurasia and North America. The research results were published in the scientific journal Nature.
“Reconstruction of the Earth’s climate over the past 24 thousand years shows that modern temperatures on the planet are unprecedentedly high for the entire period under consideration. These data indicate that the climate is changing faster than in any other era since the last glaciers,” – said Jessica Tierney , one of the study authors, assistant professor at the University of Arizona.
Scientists are studying the rate of change in the Earth’s climate to predict how the planet and its flora and fauna will change in the coming centuries. Studies show that over the past two centuries, temperatures on the planet have begun to rise tens and even hundreds of times faster than in the past several thousand years. Therefore, scientists fear that nature will not have time to adapt to the consequences of anthropogenic climate change.
Tierney and her colleagues in a new study decided to assess how the Earth’s climate has changed over the past 24 thousand years, which have passed since the so-called last glacial maximum. This is what scientists call the period in which the planet’s northern ice caps last began to advance south and covered a significant part of North America and Eurasia.
For the study, climatologists collected hundreds of samples of sedimentary rocks, consisting of the shells of marine organisms that have accumulated since the last glacial maximum, and measured the proportion of oxygen isotopes in their different layers. In addition, they found out how much magnesium and calcium, as well as various organic molecules, were present inside them.
Thanks to this, scientists have determined at what temperature and salinity of the water these rocks were formed. This made it possible to accurately reconstruct the planet’s climate over the past 24 thousand years. Thanks to a large number of rock samples from different parts of the ocean, scientists obtained data not only on average temperatures on the entire Earth as a whole, but also on climate conditions on individual continents.
Their data indicate that over the past 11-12 thousand years, temperatures on Earth have been rising smoothly. At the same time, scientists found that they are now growing noticeably faster than they fell and increased at the onset and completion of the last glacial maximum. This speaks to the unprecedented nature of the current climate change, Tierney and her colleagues concluded.
