Climate Signatures on Lake And Wetland Size Distributions in Arctic Deltas

Area of Science:

• Environmental science
• Geosciences
• Climate science

Background:

• Thermokarst lakes are sensitive indicators of Arctic climate change.
• Understanding their response to warming is crucial for carbon cycle projections.
• Distinguishing between perennial lakes and ephemeral wetlands is challenging with remote sensing.

Purpose of the Study:

• To differentiate perennial lakes from ephemeral wetlands across 12 Arctic deltas.
• To analyze the distinct size distributions and climate trends of these water bodies.
• To investigate the relationship between Arctic warming and thermokarst lake dynamics.

Main Methods:

• Rigorous separation of perennial lakes and ephemeral wetlands using satellite observations.
• Analysis of distinct size distribution patterns (lognormal for lakes, power-law for wetlands).
• Statistical assessment of trends in water body size in relation to temperature variations.

Main Results:

• Perennial lakes exhibit a lognormal size distribution, while wetlands follow a power-law distribution.
• No significant temperature trend was observed for ephemeral wetlands.
• A statistically significant decrease in mean perennial lake size was found with increasing temperatures.

Conclusions:

• Warmer temperatures lead to a reduction in the size of Arctic thermokarst lakes.
• Deeper permafrost in colder regions supports larger lakes, influencing landscape carbon storage.
• The distinct responses of lakes and wetlands to warming necessitate tailored monitoring strategies.