Hellmann et al., JGR—Biogeosciences

Soviet-era timber litters Arctic shores

The shorelines of Arctic islands are littered with driftwood—and much of it, a new study suggests, came from Soviet-era logging in central Siberia. For millennia, driftwood originating from the boreal forests of North America, Europe, and Asia has hitched a ride on sea ice, traveling with the Transpolar Drift Stream current across the Arctic Ocean until it intercepts the shores of Greenland, Iceland, Svalbard, or the Faroe Islands. When the ice melts in the summer, it leaves behind massive driftwood deposits. Although earlier studies suggested the majority of wood in these deposits is thousands of years old, the new research tells a rather different story. Building on earlier work, which showed that much of the wood came from central Siberia, a team of researchers has now dated a large fraction of the 2556 driftwood samples they collected from Arctic shores. They analyzed tree-ring width patterns for 969 samples of the dominant species of driftwood at all sites, a Siberian pine called Pinus sylvestris. They then created a “floating” chronology for each—a growth history with unknown beginning and end dates. To pinpoint precisely when the trees died, they compared these floating chronologies with an archive of dated ones for the same species in the Russian boreal forest. At least 324 of the 498 dated samples were from logged trees. Of those, 75% had been felled between 1920 and 1975, peaking around 1960, the team reports this month in Arctic, Antarctic, and Alpine Research. Logging in the Soviet Union increased through the 1920s and 1930s and hit a peak after World War II. In the early decades of commercial logging, large percentages of the timber rafted on the Yenisei and other Siberian rivers were lost, but new techniques led to a significant decrease in lost logs by 1975.