Study finds alpine peaks are greening in Northeast U.S., Canada

by Dartmouth College
September 24, 2026

In northeastern North America, a 500-mile-long stretch of mountains runs from the Adirondacks in New York to the Gaspé Peninsula in eastern Quebec.

Nearly 70 million people live within a day’s drive of one of the alpine zones, the area above tree line where trees don’t grow due to the harsh conditions.

The ecological habitats, which include the alpine zones in the Green Mountains and the White Mountains, are home to many rare species of flowering plants, making the areas hotspots for biodiversity. However, with climate change and rising temperatures, the alpine zones are impacted by declining snow cover, atmospheric nutrient deposition, and high-impact outdoor recreation where invasive species may be tracked in by hikers, hunters, bikers, skiers, and others enjoying the mountain terrain.

While prior research has examined greening in regions such as the Alps, the Rocky Mountains, and the Arctic, in relation to climate warming and other processes, Jonathan Chipman ’90, director of the Citrin Family GIS/Applied Spatial Analysis Laboratory at Dartmouth, noticed that a regional-scale assessment of what’s been happening above tree line in northeastern North America was lacking.

Given that Dartmouth is home to remote sensing and technical expertise in processing satellite imagery and time series data, and the Appalachian Mountain Club has a huge amount of alpine ecology expertise on the ground from fieldwork and citizen science projects, Chipman teamed up with co-author Jordon Tourville, a terrestrial ecologist at the Appalachian Mountain Club, to research the topic further.

“This study was a perfect collaboration between a university and a nongovernmental organization in the region, as we don’t just want to be doing this research in the abstract, but we want to help land managers, other stakeholders, and the public understand what is happening in the region,” says Chipman.

In a new study led by Chipman using hundreds of satellite images over 40 years, the team provides the first regional analysis of greening trends in the northern Appalachian region.

Keep reading: https://www.eurekalert.org/news-releases/1145447

Read the Ecosphere paper: https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecs2.70765