A new study reconstructs the path of frozen trees as they made their way across the Arctic Ocean over 500 years, giving scientists a unique look into changes in sea ice and currents over the last half millennium.
By dating and tracing pieces of driftwood on beaches in Svalbard, Norway’s archipelago in the Arctic Circle, scientists have determined where these fallen trees floated. Retracing the driftwood’s journey let the researchers reconstruct, for the first time, both the level of sea ice over time and the currents that propelled the driftwood-laden ice.
Borne by rivers to the ocean, fallen trees from the north’s expansive boreal forests can be frozen in sea ice and float far, but the new research shows fewer trees are making the long journey as the sea ice that carries them shrinks away.
The new study found a distinct drop in new driftwood arrivals over the last 30 years, reflecting the steep decline in sea ice coverage in a warming Arctic and provides a higher-resolution picture of past Arctic Ocean conditions than other methods allow. The study is published in the Journal of Geophysical Research: Oceans, which publishes research that advances our understanding of the ocean and its processes.
Read more at American Geophysical Union
Image: Geoscientist Georgia Hole used tree rings to retrace the paths of driftwood, once frozen in sea ice, as it made its way through the Arctic. “Some of these beaches are really full of driftwood—driftwood as far as the eye can see. And when you remember that these areas we were studying had no forest, completely treeless, it gives you that sense of scale.” -GH (Credit: Georgia Hole)