The presence of macro-algal agglomerates at the sea surface was
also detected by X-band SAR instruments, unaffected by cloud
covering and with a higher spatial resolution. Unlike micro-algal
blooms which appear as low backscattering areas in SAR images and
are potentially confused with oil spills (Bentz et al., 2004; Sipelgas and
Uiboupin, 2007), macro-algae agglomerates in full bloom consist of a
four- or five-inch (10–13 cm)-thick carpet at the sea surface that
appears as a rough and reflective feature.