Apr 9, 2017

Rapid decline in river icings detected in Arctic Alaska: Implications for a changing hydrologic cycle and river ecosystems

Pavelsky, Tamlin M., Zarnetske, Jay P.
Geophysical Research Letters

This is the first clear evidence that this important component of Arctic river systems - which we didn't know was changing - is changing and it's changing rapidly.

Tamlin Pavelsky, a hydrologist at the University of North Carolina Chapel Hill and lead author of the new study

  • States that liquid water emerging from groundwater and flowing through Arctic rivers during the winter often freezes into large ice features, which are called river icings
  • States that, up until now, no study has systematically looked at whether these features are changing in response to warming temperatures
  • Uses daily satellite imagery available over northern Alaska from 2000 to 2015 in order to test whether icings are becoming smaller or disappearing earlier in the summer
  • Finds that—of 147 features examined—84 are either becoming smaller (for those that persist throughout the summer) or are disappearing earlier (for those that fully melt each summer); none are becoming larger or disappearing later
  • States that these changes may be directly related to warming temperatures, but they may also be happening because climate change is altering how rivers and groundwater interact
  • Concludes that if these trends continue, we may see changes in the form of many Arctic rivers and impacts on the habitat of animals like fish and caribou