New Study: More Icebergs Are Changing Life on the Arctic Seafloor

The number of icebergs in the Arctic has increased significantly since the beginning of the 2000s, and this development is affecting both the marine environment and shipping. This is the conclusion of a new study published in the journal Nature, carried out with the participation of researchers from DTU Space.

The researchers combined nearly 40 years of iceberg observations in the Fram Strait between Greenland and Svalbard with satellite data, sea-ice models, and seafloor investigations. The analysis shows that the occurrence of icebergs has quadrupled since 2000.

According to the study, this development is due to several large glaciers in Northeast Greenland becoming less stable and calving more ice. At the same time, sea ice has become less extensive and more mobile, making it easier for icebergs to drift long distances across the Arctic.

The icebergs transport large quantities of rocks and sediments from land hundreds of kilometres out to sea. When this material sinks to the seabed, it creates new hard surfaces on the otherwise soft seafloor nearly 2,500 metres below the ocean surface. This provides opportunities for sponges, sea anemones, and other sessile organisms to establish themselves.

Professor at DTU Space and co-author of the study, Shfaqat Abbas Khan, points out that climate change is affecting the entire Arctic system.

-“When Greenland’s ice melts, sea levels rise. But we can also see that these changes affect the entire Arctic system. The effects can be traced from the glaciers of Northeast Greenland to the seafloor several thousand metres below the ocean surface and to the waters where shipping traffic is increasing,” he says.

The study also shows that the consequences of changing glaciers extend beyond rising sea levels.

-“We know from measurements and satellite observations that the large glaciers in Northeast Greenland have lost stability over recent decades. The new study shows that the consequences do not stop at rising sea levels but directly affect deep-sea ecosystems far from the glaciers,” Shfaqat Abbas Khan emphasizes.

The researchers also point out that the growing number of icebergs may create challenges for activities in the Arctic. As reduced sea ice opens new shipping routes, the risk increases that cruise ships and cargo vessels will encounter icebergs during navigation.

The researchers therefore highlight the need for improved monitoring and forecasting of ice conditions for shipping, fisheries, and other activities in the region.

-“The Arctic is responding to global warming faster than most other places on Earth. Therefore, it is crucial to understand the interaction between ice sheets, the ocean, and ecosystems. This knowledge is necessary if we are to predict and manage the consequences of future climate change,” says Shfaqat Abbas Khan.

The study was led by the Alfred Wegener Institute and Woods Hole Oceanographic Institution in collaboration with researchers from, among others, DTU Space.