Ocean Color Reveals Phase Shift Between Marine Plants and Yellow Substance

• Main Authors: Hu, Chuanmin, Lee, Zhongping, Muller-Karger, Frank E., Carder, Kendall L., Walsh, John J.
• Other Authors: UNIVERSITY OF SOUTH FLORIDA ST PETERSBURG DEPT OF MARINE SCIENCE
• Format: Text
• Language: English
• Published: 2006
• Subjects: Biological Oceanography; Physical and Dynamic Oceanography; *ORGANIC MATERIALS; *NORTH ATLANTIC OCEAN; *ABSORPTION COEFFICIENTS; *PHASE SHIFT; *PHYTOPLANKTON; REPRINTS; REMOTE DETECTORS; CHLOROPHYLLS; YELLOW(COLOR); AQUATIC PLANTS; REMOTE DETECTION; DISSOLVING; BIODEGRADATION; REFLECTANCE; OCEAN SURFACE; *COLOR DISSOLVED ORGANIC MATTER; YELLOW SUBSTANCES; GELBSTOFF; CDOM(COLOR DISSOLVED ORGANIC MATTER); DOM(DISSOLVED ORGANIC MATTER); BIOGEOCHEMICAL CYCLES; OCEAN COLOR; REMOTE SENSING; SEA WIFS(SEA-VIEWING WIDE FIELD-OF-VIEW SENSOR); PE0601153N; NRLWU738404B4; North Atlantic
• Online Access: http://www.dtic.mil/docs/citations/ADA449293; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA449293

Daily high-resolution Sea-viewing Wide Field-of-view Sensor (SeaWiFS) images of the central North Atlantic Ocean (199-2OO3) show that temporal changes in the absorption coefficient of colored dissolved organic matter (CDOM) or "yellow substance" follow changes in phytoplankton pigment absorption coefficient in time. CDOM peaks (between January and March) and troughs (late summer and fall) followed pigment peaks and troughs by approximately two and four weeks, respectively. This phase shift is additional strong evidence that CDOM in the marine environment is derived from phytoplankton degradation. The common assumption of linear covariation between chlorophyll and CDOM is a simplification even in this ocean gyre. Due to the temporal changes in CDOM, chlorophyll concentration estimated based on traditional remote sensing band-ratio algorithms may be overestimated by about 10% during the spring bloom and underestimated by a similar 10% during the fall. These observations are only possible through use of synoptic, precise, accurate, and frequent measurements afforded by space-based sensors because in situ technologies cannot provide the required sensitivity or synoptic coverage to observe these natural phenomena. Index Terms Biogeochemical cycle, colored dissolved organic matter (CDOM), ocean color, phase shift, phytoplankton, remote sensing, sea surface reflectance. Pub. in IEEE Geoscience and Remote Sensing Letters, v3 n2 p262-266, April 2006.