Karakoram Glacier Anomaly Solved: Why the Ice Has Remained Stable in the Himalayas

Scientists may have managed to solve the "Karakoram anomaly," a phenomenon that has long puzzled climate change researchers. They've found that the glaciers in the Karakoram mountains have remained surprisingly stable over the past 150 years due to a unique and localized seasonal pattern.

The Karakoram mountains are a mountain range located within the Himalayas. Yet the glaciers on these mountains have remained stable for years, though scientists have been unable to explain why this is as temperatures have warmed. That's why they decided to take a closer look at these glaciers.

The Karakoram features dramatic shifts in elevation over a small area. In fact, the range boasts four mountains that are more than 26,246 feet high, including K2, the world's second highest peak. In order to overcome this elevation obstacle, the scientists used high-resolution computer models to break the Karakoram into 50-km pieces. Comparing their model with climate models from the United Nations' Intergovernmental Panel on Climate Change (IPCC), they were able to get a better sense of what factors influenced the glaciers.

"The higher resolution allowed us to explore what happens at these higher elevations in a way that hasn't been able to be done," said Sarah Kapnick, the first author of the new study, in a news release. "Something that climate scientists always have to keep in mind is that models are useful for certain types of questions and not necessarily for other types of questions. While the IPCC models can be particularly useful for other parts of the world, you need a higher resolution for this area."

In this case, the scientists noted that the secret behind the stable glaciers is a localized seasonal pattern that keeps the mountain range relatively cool and dry during the summer. More specifically, the main precipitation system that affects this mountain range occurs in the winter and is influenced by cold winds coming from Central Asian countries such as Afghanistan to the west. The main Himalayan range also blocks warmer air from the southeast throughout the year.

"Our work is an important piece to understanding the Karakoram anomaly," said Kapnick. "But that balance of what's coming off the glacier versus what's coming in also matters for understanding how the glacier will change in the future."

The findings are published in the journal Nature.