Cold and Dusty: Ecological Consequences of Aeolian Landscape Change in West Greenland
Ruth Heindel, Assistant Professor of Environmental Studies at Kenyon College
The global dust cycle has profound implications for Earth’s climate system, ecosystem functioning, and human health. Recently, polar regions have been gaining recognition as important dust sources, but our knowledge of detailed local dynamics remains limited. This talk will consider the ecological consequences of soil deflation in Kangerlussuaq, West Greenland, an Arctic dust source region where strong katabatic winds have resulted in distinct erosional landforms. I will show that these blowouts, or deflation patches, are a critical component of the Kangerlussuaq ecosystem, accounting for 10% of the terrestrial landscape and impacting vegetation dynamics by providing habitat for graminoid, herbaceous, and lichen species. Deflation patches formed 230-800 years ago, during cold, dry, and windy climate conditions. The landforms are actively eroding and producing dust, with geomorphic change detectable even over a short two-year time period. The future trajectory of deflation patches depends on the role of biological soil crusts as either a successional facilitator or a long-term landscape cover. I suggest that deflation patches may persist on the landscape for centuries or millennia if precipitation and temperature regimes do not dramatically alter the vegetation potential of the region.
In addition to providing an in-depth discussion of what we have learned about soil erosion dynamics in Kangerlussuaq, I will consider potential future directions of this work. For instance, how widespread are these landforms across Greenland and the Arctic? What is the fate of the dust generated from these erosional landforms? What role will biological soil crusts play as the Greenland Ice Sheet continues to retreat? Finally, I will provide a few highlights from other areas of my (cold and dusty) research program, including local aeolian transport in the McMurdo Dry Valleys of Antarctica and dust deposition in the Front Range of Colorado.