The brownish-grey algae that darken the Greenland ice sheet in summer cause the ice to melt faster, but only recently have scientists measured these blooms in the field, and only at few sites. To measure algal blooms across large regions and understand their effects on melting over time, scientists are now turning to space.
“Scientists go into the field and sample one or two spots where these algal blooms occur, but we don’t really know how they change over time or over a large region,” said Shujie Wang, assistant professor of geography at Penn State. “To solve this problem, my research team and I borrowed the methodology used to measure algae in water, which uses ocean color satellites and has a long history.”
The algae that bloom on water differ from those that bloom on ice, but both species contain chlorophyll-a, which has a distinct reflected near-infrared radiation signature that satellite sensors can detect.
Read more: University of Penn State