New Arctic map tracks 4 million lakes, but the 'lost' ones may reveal permafrost thaw

A new interactive map is giving scientists and the public a closer look at one of the Arctic's fastest-changing features: its lakes.

The Lost Lakes database can track changes in roughly 4 million Arctic lakes almost as they happen, and the lakes that disappear may be among the most revealing, Mongabay reported.

Here's what to know

Users can explore lakes across the Arctic with the map, including many that lie over permafrost, ground that stays frozen for long periods. 

The record goes back to 2016, so users can compare how those lakes have changed over time.

What happens to these lakes depends on how warming reshapes the frozen terrain below them. 

Thaw can cause the ground to sink and collect water, creating new ponds and lakes, while in other places it opens channels that let existing lakes drain.

Because direct, large-scale monitoring below ground is much harder, remote sensing researcher Ingmar Nitze of Germany's Alfred Wegener Institute said lake changes can indicate what is happening underneath the surface.

"LostLakes is completely free and designed to be used by experts and non-experts at the same time," Nitze told Mongabay.

More background

The climate stakes are high because permafrost locks away huge quantities of organic material from plants, animals, and microbes. 

When it thaws, some of that stored carbon can escape into the atmosphere.

Moreover, the region is warming faster than the world as a whole. 

Directly measuring permafrost usually means digging into the ground because it sits below the surface. Lakes are easier to observe, giving researchers a visible sign of change from above.

Nitze explained that those landscape shifts do not always happen quickly. 

"In west Alaska we have some ponds that started forming in the mid 20th century. Many Arctic lakes started forming around 12,000 years ago," he added.

Although Arctic lakes naturally appear and disappear, changes in how many are shifting — and how fast — can signal wider permafrost degradation.

What's being done?

Because the map is free and open to the public, it could give scientists, residents, and planners a clearer sense of where the landscape may be becoming less stable.

Nitze and University of Alaska Fairbanks researcher Anna Liljedahl wrote in The Conversation that areas with more ice-rich permafrost may be less suitable for building, while places with less ground ice could be safer.

The map also helps capture abrupt events that might otherwise go unnoticed. 

In northwestern Alaska, for example, close to 200 lakes shrank in summer 2018 after a very warm winter, according to Nitze and Liljedahl.

"Once the permafrost thaws, some of this carbon, which was freeze-locked there for thousands of years, can go to the atmosphere and further fuel the warming, which may lead to a faster permafrost thaw," Nitze noted.

Where can I learn more?

These articles focus on other changes affecting northern lakes and the broader Arctic systems around them. They cover gaps in Arctic data, pollution in remote waters, and rapid lake changes in other cold regions.

• In Russia, missing standardized Arctic data is leaving scientists with major gaps in their knowledge.

• Across the northern United States, sparse lake ice cover has left winter conditions increasingly unreliable.

• In Finnish Sápmi, microplastic pollution in lakes is altering water relied on by Sámi communities.

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