Over the past 40 years, aerial images have shown how the Alsek Glacier and the Grand Plateau Glacier have been shrinking. As they melted, Alsek Lake expanded, taking over the space left by the retreating ice. Recently, NASA’s Landsat 9 satellite captured a significant moment: the last piece of ice separating Prow Knob from a glacier, officially turning it into an island. This event occurred between July 13 and August 6 this summer.
Historically, in the early 20th century, the Alsek Glacier stretched much further, reaching Gateway Knob, about three miles from Prow Knob. Glaciologists note that since 1984, the glacier has retreated over three miles. During this same period, Alsek Lake has almost doubled in size, growing from about 17 square miles to nearly 30 square miles due to the meltwater runoff.
Research shows that proglacial lakes like Alsek form as glaciers melt, and they can grow rapidly. A study published by the journal Earth Science Reviews highlights that the increase in these lakes can affect local ecosystems and climate patterns. Experts predict even more melting in the future, especially now that the ice has disconnected from Prow Knob, making it more vulnerable.
As our climate continues to change, understanding these shifts in glacial dynamics is essential. Keeping an eye on these changes helps us grasp the bigger picture of our planet’s health.
