...
By Sean Duke
Science Editor
0
Share
Newsweek is a Trust Project member
See more of our trusted coverage when you search.Prefer Newsweek on Googleto see more of our trusted coverage when you search.
The fossilized remains of Whitebark pine trees found beneath a melting ice patch in the Yellowstone region were once part of an ancient forest that thrived for centuries before disappearing, scientists believe.
The forest began to struggle about 5,500 years ago due to drops in summer temperatures. This transformed what was a high mountain tree-filled landscape into the alpine tundra there today.
"We were very surprised that these mature forests were preserved for thousands of years," Dave McWethy, assistant research professor in the Department of Earth Science at Montana State University, told Newsweek.
Read More on Better Planet
McWethy has studied the remains of the forest, which formed at an altitude of 10,000 feet about 6,000 years ago when temperatures in the Greater Yellowstone Ecosystem were similar to their current level.
When volcanic activity in the northern Hemisphere caused the temperature to plunge further, the pine forest trees became locked in ice, where they remained until it began to thaw in recent years.
"There are few examples of ancient forests above current day treeline surviving," said McWethy.
...
Yellowstone Ice Patches Melting
"Over the last few decades, we have observed a lot of year-to-year variability in how much the ice patches melt," said McWethy. "Some years the late summer melting is dramatic where the ice patch margins appear to be shrinking to new lows, and other years the melting of the previous year's snowpack is much less."
Many of the ice patches on the Beartooth plateau will disappear within decades or sooner, he says, and the release of water from melted snow could lead to changes in the plants and animals that live in the valleys below.
"As these ecosystems respond to the melting of ice patches and warming on the plateau, it is likely that trees and woody shrubs and plants will move upslope."
This could change the fire dynamics in the region, said McWethy, and create the potential for a new situation where fires are more intense and larger than before.
"We are already seeing trees begin to establish upslope in response to warming temperatures and we expect this to continue."
"A number of factors will shape when and where forests move upslope over time – for example, drier soils, wind and snowpack might limit tree establishment in some areas."
Why Does This Matter?
There is a danger, McWethy says, that as the ice patches melt information about past cultures, climates and environments will be lost, unless scientists can retrieve it beforehand.
It's also important to use the discoveries made possible by the thaw to learn more about alpine climate systems, and how they respond to rapid, as well as long-term changes in climate.
"These alpine environments provided important habitat for animals and were inhabited and used by people for thousands of years," said McWethy.
"They also likely provided an important refuge for animals and humans during multi-decadal droughts when conditions were hot and dry in the valleys and fire activity was more intense."
Do you have a tip on a science story that Newsweek should be covering? Do you have a question about fossils? Let us know via science@newsweek.com.
View 0 Comments
Submit Correction
View Editorial & AI Guidelines