Boreal forests are expanding northward due to climatological warming, satellite images show

Boreal forests are continuing to shift northward as they warm, satellite images taken over the last several decades show.

Boreal forests are continuing to shift northward as they warm due to climate change, satellite images taken over the last several decades show.

Boreal forests are the world's largest terrestrial biome – meaning a region characterized by a predominant ecological type – and have "experienced the fastest climatological warming of any forest biome," according to a paper published in the journal Biogeosciences. Annual surface temperatures across boreal forests have increased about 1.4 degrees Celsius, or 2.52 degrees Fahrenheit, over the last century, according to the study.

The research reveals "unprecedented changes" in boreal forests, a "critical ecosystem" that stores more than a third of the world's forests and helps regulate our global climate, NASA said.

Researchers analyzed nearly a quarter million satellite images taken between 1985 and 2020 as part of the Landsat program, the longest-continuous space-based record of Earth's land run by NASA and the U.S. Geological Survey. The images contain the longest and highest-resolution satellite record of calibrated tree cover to date, according to NASA.

The NASA images confirmed a northward shift in boreal forest cover over the last four decades, as well as a 12% increase in size, according to the Biogeosciences paper.