Alaska’s landscape is undergoing a dramatic transformation, one that is both visible and alarming. Unlike Florida’s well-known sinkholes, Alaska’s ground is collapsing due to the thawing of permafrost—ground that remains frozen for at least two consecutive years. As temperatures rise, this permafrost is melting, leading to significant property damage and environmental changes.
The consequences of this thawing are far-reaching. Buildings, roads, and pipes are at risk as the land beneath them sinks. Yet, despite the high potential for damage, up-to-date maps of permafrost thaw are often rare. To address this gap, a team of hydrologists and data scientists has created an interactive website to track permafrost thaw in near-real time across the Arctic.
Clear signs of permafrost thaw
Permafrost thaw is not directly measurable without digging into the ground, but there are clear signs to watch for. When ice-rich permafrost thaws, the ground surface subsides, creating thermokarst ponds—depressions that fill with water. These ponds are becoming increasingly common across the Arctic, where temperatures are rising at two to three times the global average rate.
Satellite imagery makes it easy to spot these lakes, and monitoring their changes over time provides clues about how the permafrost is changing below. Sometimes, the same process that creates these ponds can also form new stream channels that drain the lake, leaving behind a circular basin of bare ground. A lake that took a millennium to form can disappear in just a few hours due to permafrost thaw triggered by an unusually warm summer.
The rapid disappearance of lakes
When a lake abruptly disappears, it is a strong indicator that the ice-rich permafrost has thawed. This phenomenon provides a way to monitor permafrost over wide areas and track where thawing is most active. Aerial photos from the late 1940s and satellite imagery from the 1970s have helped scientists map the Arctic’s permafrost landscapes, including where its permafrost lakes were and are not.
Using artificial intelligence, scientists can quickly analyze new images from across large swaths of the Arctic for signs of permafrost changes, such as the appearance of new ponds or the disappearance of old ones. An international team of scientists, working through the Permafrost Discovery Gateway, has mapped and now actively monitors over 4 million lakes across the Arctic, including 70 million thermokarst ponds across the Alaska tundra.
Permafrost changes underway in 2026
The Seward and Baldwin peninsulas in northwestern Alaska are hot spots for lakes suddenly draining. Over the past two decades, this region has lost many large lakes that had covered its landscape for thousands of years. In the summer of 2018 alone, almost 200 of the region’s approximately 4,600 lakes lost more than a quarter of their area following an unusually warm winter.
Although the winter of 2026-26 was colder for Alaska, this region continued to lose lake area, suggesting evidence of permafrost thaw. Around 30 more lakes were affected by drainage in June and July 2026. This process happens with hundreds of lakes across the Arctic every summer, especially in June and July. However, not all lake changes are caused by permafrost thaw.
For example, lakes in floodplains and wetlands can change dramatically across each season due to the abundance of snowmelt water in spring. Wildlife can also play a role. Beavers, for example, can recreate a lake after it abruptly drained by blocking the newly formed drainage channels.
In the past, information about where permafrost was changing was primarily available through scientific studies published years later. With near-real-time data available today, researchers can more closely study the processes of permafrost thaw, and communities can get up-to-date insights about the status of the permafrost before they plan new construction, and know where they’re likely to have trouble.
