The world’s mountain regions are warming swiftly

North Tenmile Creek trail, Frisco Colorado — Global warming will have profound impacts on mountain ecosystems, **@bberwyn photo.**

Scientists say there’s an urgent need for more widespread data collection and observations from high elevations

By Bob Berwyn

A new scientific report from climate scientists says the world’s highest mountains may be warming much faster than than the global average — and faster than previously thought.

Most of all, the researchers said more monitoring and observations of mountain temperature patterns are needed to assess the high-elevation changes.

Absent that data, there’s a risk of underestimating looming environmental challenges, including water shortages and the possible extinction of some alpine flora and fauna, the scientists reported in their new study.

The reseach team includes Henry Diaz and Imtiaz Rangwala from CIRES, the Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder. Both researchers are part of NOAA’s Earth System Research Laboratory. The team’s report is published in the journal Nature Climate Change.

“There is growing evidence that high mountain regions are warming faster than lower elevations and such warming can accelerate many other environmental changes such as glacial melt and vegetation change,” said lead author, Nick Pepin of the University of Portsmouth.

Fifty years of data from the Tibetan Plateau show clear trend of rising temperatures, and the rate is increasing, but there are distinct differences at different elevations. During the past 20 years, temperatures above 13,000 feet have warmed about 75 percent faster than in areas below 6,500 feet.

Spatial differences are also evident in Colorado where key measurements at Niwot Ridge —with climate records going back more than 60 years — show big variations just a few miles apart. At one high elevation site, the climate has been getting slightly wetter and cooler in recent decades. But data from nearby station at 10,000 feet in a subalpine forest is getting significantly warmer and drier.

But scientists need more and better data to confirm the trends, because there are so few observations from 11,000 feet or higher.

“It’s understandable. Mountains are difficult to study, they are remote and often inaccessible, and it is expensive and often challenging to find ways of effectively monitoring what is happening,” Pepin said. “Mountains are also very complicated landscapes, and have a wide variety of microclimates which makes it hard to see the overall picture.”

That lack of data makes it hard to pinpoint regional temperature trends in the Rocky Mountains, according to Diaz. There are only a few long-term observation sites with data going back more than a decade.

Records of weather patterns at high altitudes are “extremely sparse,” the researchers found. The density of weather stations above 4,500 m is roughly one-tenth that in areas below that elevation. Long-term data, crucial for detecting patterns, doesn’t yet exist above 5,000 meters anywhere in the world. The longest observations above this elevation are 10 years on the summit of Kilimanjaro.

The team of scientists came together as part of the Mountain Research Initiative, a mountain global change research effort funded by the Swiss National Foundation. The team includes scientists from the UK, United States, Switzerland, Canada, Ecuador, Pakistan, China, Italy, Austria and Kazakhstan. Between them, they have studied data on mountain temperatures worldwide collected over the past 60-70 years.

Improved observations, satellite-based remote sensing and climate model simulations are all needed to gain a true picture of warming in mountain regions, said Raymond Bradley, a climatologist at the University of Massachusetts and one of the report’s co-authors.

“We are calling for special efforts to be made to extend scientific observations upwards to the highest summits to capture richer data on what is happening across the world’s mountains,” Bradley said. “We also need a strong effort to find, collate and evaluate observational data that already exists wherever it is in the world. This requires international collaboration.”