Swedish researchers find Ice Age ‘missing link’

As world leaders prepare to meet in Paris for the next climate change conference, a team of researchers in Sweden have uncovered a 'missing link' in our understanding of the last Ice Age.

Swedish researchers find Ice Age 'missing link'
Photo: Björn Eriksson

For years, researchers have struggled to resolve inconsistences between climate models of the earth 13,000 years ago with their understanding of how the North Atlantic system responds to climate change. But new findings may have helped solve the riddle.

“The melting of the Scandinavian ice sheet is the missing link,”announced Francesco Muschitiello, a PhD researcher at Stockholm University.

The prevailing theory among scientists has been that a catastrophic freshwater flood from the melting North American ice sheets plunged the planet into a sudden and final cold snap (just before entering the present warm interglacial period).  However models and reconstructions of the period just didn’t line up.

But an international team of scientists, led by Swedish researchers from Stockholm University, have finally found the missing link – in sediment from an ancient Swedish lake.

“Moisture-sensitive molecules extracted from the lake’s sediments show that climate conditions in Northern Europe became much drier around 13,000 years ago,” Muschitiello said.

Researcher Francesco Muschitiello. Photo: Stockholm University

According to Muschitiello, the colder and drier climate conditions were likely driven by accelerated melting of the Scandinavian ice sheet in response to warming at the end of the last Ice Age.

The Scandinavian ice sheet was the force that tipped the dominoes, leading to an expansion of summer sea ice, changing ice distribution in the eastern region of the North Atlantic – and eventually causing abrupt climate change.

Finally, the climate models make sense, added Franceso Pausata, postdoctoral researcher at Stockholm University.

“When forcing climate models with freshwater from the Scandinavian Ice Sheet, the associated climate shifts are consistent with our climate reconstructions.”

Read also: 11 reasons to study at Stockholm University

Professor Barbara Wohlfarth, project leader at Stockholm University, added that the research results highlight how important studies of the earth’s past climate changes are – especially in the context of the current climate change debate.

“The Scandinavian ice sheet definitely played a much more significant role in the onset of this final cold period than previously thought.”

This article was produced by The Local in partnership with Stockholm University


Nobel Prize in Chemistry awarded for ‘ingenious tool for building molecules’

The Royal Swedish Academy of Sciences in Stockholm, responsible for awarding the Nobel Physics and Chemistry Prizes, has announced the winners of the 2021 Nobel Prize in Chemistry.

Peter Somfai, Member of the Nobel Committee for Chemistry, announces the winners for the 2021 Nobel Prize in Chemistry.
Peter Somfai, Member of the Nobel Committee for Chemistry, announces the 2021 winners. Photo: Claudio Bresciani

The prize this year has been awarded to Germany’s Benjamin List and David MacMillan from Scotland, based in the US.

The Nobel Committee stated that the duo were awarded the prize “for their development of a precise new tool for molecular construction: organocatalysis”. The committee further explained that this tool “has had a great impact on pharmaceutical research, and has made chemistry greener”.

Their tool, which they developed independently of each other in 2000, can be used to control and accelerate chemical reactions, exerting a big impact on drugs research. Prior to their work, scientists believed there were only two types of catalysts — metals and enzymes.

The new technique, which relies on small organic molecules and which is called “asymmetric organocatalysis” is widely used in pharmaceuticals, allowing drug makers to streamline the production of medicines for depression and respiratory infections, among others. Organocatalysts allow several steps in a production process to be performed in an unbroken sequence, considerably reducing waste in chemical manufacturing, the Nobel committee at the Royal Swedish Academy of Sciences said.

The Nobel committee gave more information in a press release as to why List and MacMillan were chosen: “Organocatalysis has developed at an astounding speed since 2000. Benjamin List and David MacMillan remain leaders in the field, and have shown that organic catalysts can be used to drive multitudes of chemical reactions. Using these reactions, researchers can now more efficiently construct anything from new pharmaceuticals to molecules that can capture light in solar cells. In this way, organocatalysts are bringing the greatest benefit to humankind.”

List and MacMillan, both 53, will share the 10-million-kronor prize.

“I thought somebody was making a joke. I was sitting at breakfast with my wife,” List told reporters by telephone during a press conference after the prize was announced. In past years, he said his wife has joked that he should keep an eye on his phone for a call from Sweden. “But today we didn’t even make the joke,” List said. “It’s hard to describe what you feel in that moment, but it was a very special moment that I will never forget.”