Monitoring Melt Due to Red Algae on The Harding Icefield 2013-2019

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The Harding Icefield is located in Southcentral Alaska on the Kenai Peninsula. The icefield covers over 700 square miles, approximately the size of the island of Maui. It is the largest icefield wholly contained in the U.S.. Melt on the Harding and other icefields has been consistently increasing over the last 30 years due to a multitude of factors. The most publicized of which is warming temperatures due to climate change, but this is not the only environmental shift that is impacting icefield melt rates. Chlamydomonas nivalis, better known as watermelon snow, lives on the oligotrophic surface of icefields and is adapted for melt potential. This organism is a photosynthetic algae that uses its absorptive red pigment to melt the snow surrounding it. Red algae requires this water for it’s photosynthetic process and for nutrient delivery as compounds such as nitrogen and phosphorus are only accessible through flowing water on icefields. This algae is so well adapted that it is responsible for upto 17% of icefield melt per day. On average that is 6 gigaliters or 2400 olympic swimming pools per day. Using ArcGIS and spectral data from satellite imagery, (Landsat missions) we are able to monitor algae concentrations on the Harding Icefield. From these concentrations we are able to estimate melt due to algae abundance. Our findings show an increasing trend in not only abundance of red algae, but also melt due to red algae from 2013-2019.