The world is changing, literally. According to two new studies out of Virginia Tech, the highest mountain tops and the lowest coastal areas are morphing, slowly remaking the landscape.
Once bare mountain peaks, now have trees growing above what used to be called ‘the tree line.’
Let’s start at the top, where glaciers have been retreating at, well, a glacial pace, since the 1960s.
"But in the last couple of decades, the, the pace of glacier retreat has really accelerated. And there's really only a few glaciers left in glacier national park."
That’s Lynn Resler an ecological bio-geographer. She studies the highest mountains in the U.S. and how vegetation is changing way up there.
She says, “We’re seeing things like trees becoming more susceptible to invasive species moving into places where they were not previously found.”
Resler has been studying the white bark pine, which is what’s called a Keystone species. That’s because it’s key to the entire ecosystem it inhabits. An important protein source for grizzly bears, it shares a mutualistic relationship with birds like the Clark's Nutcracker, and supports many other species down the chain.
She says, “When we see cascading changes and cascading effects of invasive species or invasive pathogen, we really have to start paying attention because it's more than just an impact on a single species.”
It takes a trained eye and a lot of patience to document these changes, because the effects of climate change are subtle and relatively slow. Resler is not a climate scientist, but she has been studying these changes for a long time.
Many years ago, she says, “I remember my parents took me to Rocky Mountain National Park, and we drove above tree line. And there was a hike that went out into the Alpine environment and I walked out there, and I just felt like this was a completely different world. And at that moment, I said to myself, if I could, you know, research this or spend the rest of my life here, I would.”
Most years, she takes teams of students to the highest peaks, where they camp and record data, not this year, but the pandemic has given her much needed time to go over recent studies. And here’s what she found.
“We have seen what we call densification of the landscape, where the areas in between trees are filling in and becoming denser. And we expect that if the trend continues, we will see trees being able to establish in higher elevations where they weren't previously able to establish”.
Resler recently began studying mountains in West Virginia. She says extensive disturbance from agricultural land use, logging, and fires, shaped the characteristics of these ecosystems.
“So when we study the vegetation today it is challenging to determine if the changes in vegetation we are seeing are due to climate change, recovery from land use, or more likely, a combination of both.”
She says these disturbances have begun to threaten an important species, the once abundant Red Spruce tree, found only in places like the Appalachian Mountains where the climate is relatively cool and wet.
“Seeing Red Spruce is quite special to many people because it kind of makes you feel like you're somewhere else.”
She says ultimately, a warming climate will further stress “these mountain ecosystems, primarily because of the rate at which it is occurring.
So, from the highest mountains, to the lowest coastal lands, landscapes are being re-made. In our next report we’ll hear how coastal flooding is not only changing the landscape but raising new questions for residents about whether to stay put or head for higher ground.