Permafrost in the Arctic stores large quantities of organic carbon. When the frozen ground thaws or coastal sections erode, this carbon can enter the sea, where microorganisms can break it down and convert it into climate-damaging greenhouse gases. The extent to which this carbon actually enters the atmosphere, however, and how much remains in the ocean has hardly been quantified to date. Researchers from the Alfred Wegener Institute and MARUM – Centre for Marine Environmental Sciences at the University of Bremen have now been able to answer this question for the first time for the permafrost coast of Qikiqtaruk (Herschel Island) in Canada. With the help of sediment cores, they discovered that considerable amounts of terrestrial carbon are stored in the seabed. It also became apparent that microorganisms are particular gourmets who decidedly prefer fresh marine carbon. The researchers published their findings in the journal Nature Geoscience.

Calcium isotopes in fossilized shells show ocean acidification caused the extinction event. Massive volcanic eruptions released CO2 into the atmosphere, acidifying seawater. Fifth Northwestern study to link volcanic eruptions to ocean acidification and extinction. Ancient events help scientists understand current CO2 increases and potential consequences.

Hot fluids rising from Earth's interior have been driving mineral formation on the ocean floor for millions of years. In a new study, an international team of scientists led by first author Dr. Joely Maak (MARUM) now shows that microorganisms can also play a central role. At a hydrothermal system discovered off the Greek island of Milos at intermediate water depths in 2023, the team demonstrated how different intensities of hydrothermal fluid flow favor distinct microbial metabolisms and, in turn, control the formation of different minerals.

Norway’s ambitious Arctic Ocean 2050 program has launched its first major expedition, sending the research icebreaker Kronprins Haakon toward the North Pole to investigate how a rapidly changing Arctic will look and function in the decades ahead.

Rutgers University oceanographers Joe Gradone and Corday Selden are preparing to step into the most consequential assignment of their careers so far.

On Aug. 7, they will board the research vessel Falkor (too) in Bridgetown, Barbados. Two days later, the ship will leave port, carrying Gradone and Selden into the Atlantic Ocean as co-chief scientists leading an international team of 19 scientists on a 25-day research expedition.