SPOT Satellite Imagery

Giant kelp forest observations using SPOT satellite imagery

Upper: SPOT-5 false color imagery overlain by classified kelp cover (green) for the mainland coast of Santa Barbara spanning from Arroyo Quemado (AQ) in the west (highlighted box) to the city of Santa Barbara in the east. Lower: SPOT-5 false color images overlain by classified kelp cover (green) for four analysis periods near AQ (the highlighted box in the upper panel). The red pixels in the lower panels represent the location and the size of the diver transects at AQ. Also shown is the total kelp wet biomass for the four subscenes. Note the two-fold changes in kelp biomass over the seven months in this time sequence. ©2007 CNES, Licensed by Terra Image USA, California, USA..

Remote sensing data have long provided a method for integrating field point and transect data sets from local to regional to global scales. We are exploring regional dynamics of giant kelp using high spatial resolution (10 & 20 m) multi spectral imagery from the SPOT-5 satellite to integrate our diver observations on kelp forests at selected sites to larger regional scales. SPOT is an acronym for Système Pour l'Observation de la Terre, a French series of high resolution Earth remote sensing satellites. Three SPOT satellites are presently in operation on orbit. UCSB was designated as a SPOT imagery research center in 2006, allowing nearly unlimited free access to existing and new SPOT imagery (add link to SPOT). Giant kelp, like most terrestrial plants, has a spectral signature characterized by high near-infrared reflectance and much lower reflectance in the green and red spectral regions. SPOT-5 provides multi-spectral imagery with ability to distinguish these spectral bands at a 10 m spatial resolution appropriate for assessing changes in giant kelp forests.We have developed a robust method for delineating pixels with kelp canopy using a near infrared to green band ratio.