Remote Sensing Phenology of Antarctic Green and Red Snow Algae Using WorldView Satellites. ...

• Main Authors: Gray, Andrew, Krolikowski, Monika, Fretwell, Peter, Convey, Peter, Peck, Lloyd S, Mendelova, Monika, Smith, Alison G, Davey, Matthew P
• Format: Article in Journal/Newspaper
• Language: English
• Published: Frontiers Media SA 2021
• Subjects: Antarctica; WorldView; ecology; remote sensing; satellites; snow; snow algae; Antarctic; Antarc*
• Online Access: https://dx.doi.org/10.17863/cam.68733; https://www.repository.cam.ac.uk/handle/1810/321615

Snow algae are an important group of terrestrial photosynthetic organisms in Antarctica, where they mostly grow in low lying coastal snow fields. Reliable observations of Antarctic snow algae are difficult owing to the transient nature of their blooms and the logistics involved to travel and work there. Previous studies have used Sentinel 2 satellite imagery to detect and monitor snow algal blooms remotely, but were limited by the coarse spatial resolution and difficulties detecting red blooms. Here, for the first time, we use high-resolution WorldView multispectral satellite imagery to study Antarctic snow algal blooms in detail, tracking the growth of red and green blooms throughout the summer. Our remote sensing approach was developed alongside two Antarctic field seasons, where field spectroscopy was used to build a detection model capable of estimating cell density. Global Positioning System (GPS) tagging of blooms and in situ life cycle analysis was used to validate and verify our model output. ...