dissolve ice has unveil clay of a long - miss woods in the Greater Yellowstone Ecosystem , indicate the fundamental changes that have influenced the domain – and perhaps what might lie ahead .
scientist at Montana State University ( MSU ) examine the remains of a mature whitebark pine tree forest that formed closely 6,000 years ago on the Beartooth Plateau in the Rocky Mountains , at an elevation of 3,091 meters ( 10,141 understructure ) . Oddly , the remains were find some 180 meter ( 590 feet ) above the dot where trees are base today , argue that conditions have importantly shifted in the region .
raft , if tall enough , will feature a treeline – a point beyond which condition are too abrasive for trees to get . Warmer temperature can extend the growing season and boil down environmental stress , allowing treelines to shift up the raft .
Scientists study an ice patch on the Beartooth Plateau in the Greater Yellowstone Ecosystem.Image credit: Joe McConnell/Desert Research Institute
Conversely , cooling shortens the produce season and increases frost stress , causing treelines to retreat downslope . Other constituent – like wet levels , wind , snowpack , and human disturbance – can also flirt a role , but temperature during the growing season is a prime divisor .
Since the treeline used to be higher in the Beartooth Plateau , it indicates that term where were once warm . The researcher work out that the trees likely produce when the mean temperatures of the warm season ( May to October ) were around 6.2 ° C ( 43 ° F ) , which is about the same as those of the mid - to - late 20th century .
The forest thrived for century before collapsing around 5,500 long time ago . Its death was drive by a meaning drop in temperatures , likely triggered by volcanic action in the Northern Hemisphere . This volcanic activity exacerbate the region ’s existing cooling trend , have temperatures to plummet further and making condition unsuitable for the woodland ’s natural selection .
“ This is pretty dramatic evidence of ecosystem variety due to temperature warming . It ’s an amazing story of how dynamic these systems are , ” David McWethy , study co - generator and associate prof in the Department of Earth Sciences in MSU ’s College of Letters and Science , said in astatement .
It ’s pretty rarified for an ancient ecosystem like this to be preserved for thousands of age . One rationality is that it became trap under an ice patch , rather than a glacier , which flow and butter churn over time . As such , the squad is hoping to tap this find to its fullest and use it to obtain rare information about Earth ’s removed past .
“ Most of our best long - term mood records come from Greenland and Antarctica . It ’s not a small thing to find ice patches that persisted for that farseeing of a time period at lower latitudes in the interior continent , ” explained McWethy .
The study is published in the journalProceedings of the National Academy of Sciences .
