Abstract
The inconstancy of the composition of phytopigments during intensive mesoscale mixing of the photic zone of the Tasman Sea was investigated from MODIS images of its surface. For this, each pixel of the image is assigned a WRM (wavelength of reflectance minimum) index equal to the sum of the wavelengths of the minima in the reflectance spectrum of the water surface within the boundaries of a pixel on the ground. The WRM is acceptable as an indicator of the inconstancy of the composition of phytopigments in the water column, since the spectra of light absorption by phytopigments in an aqueous medium change following the species affiliation of phytoplankton, even though light attenuation by water as a solvent and its admixtures of a different nature are inferior to light absorption by phytopigments in spectral selectivity. A comparative analysis of the WRM index distributions and characteristics of Tasman Sea water showed that the increased mesoscale variability of open ocean waters is accompanied by an increase in phytopigment content to a level where pigment minima appear in the spectra of backscattered solar radiation at 400–550 nm, distinguishable by multispectral ocean color scanners. This effect is not considered by common algorithms for chlorophyll determination using data from multispectral ocean color scanners (band-ratio algorithms) and is probably one of the reasons for the known tendency of such algorithms to overestimate chlorophyll concentration with respect to its actual content even in water areas free of the influence of external sources of optically significant admixtures in the water column.
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REFERENCES
B. Bergman, G. Sandh, S. Lin, et al., “Trichodesmium—a widespread marine cyanobacterium with unusual nitrogen fixation properties,” FEMS Microbiol. Rev. 37, 286–302 (2013). https://doi.org/10.1111/j.1574-6976.2012.00352.x
D. Blondeau-Patissier, J. F. R. Gower, A. G. Dekker, et al., “A review of ocean color remote sensing methods and statistical techniques for the detection, mapping and analysis of phytoplankton blooms in coastal and open oceans,” Prog. Oceanogr. 123, 123–144 (2014).
M. Bouali and S. Ladjal, “Toward optimal destriping of MODIS data using a unidirectional variational model,” IEEE Trans. Geosci. Remote Sens. 49 (8), 2974–2935 (2011).
A. V. S. Detoni and A. M. Ciotti, “Trichome abundance, chlorophyll content and the spectral coefficient for light absorption of Trichodesmium slicks observed in the Southwestern Atlantic,” J. Plankton Res. 42 (2), 13–139 (2020). https://doi.org/10.1093/plankt/fbaa009
J. D. Everett, M. E. Baird, P. R. Oke, and P. M. Suthers, “An avenue of eddies: quantifying the biophysical properties of mesoscale eddies in the Tasman Sea,” Geophys. Res. Lett. 39, L16608 (2012). https://doi.org/10.1029/2012GL053091,2012/
P. Gaube, D. B. Chelton, R. M. Samuelson, et al., “Satellite observations of mesoscale eddy-induced Ekman pumping,” J. Phys. Oceanogr. 45, 115–132 (2015).
C. Hu and L. Feng, “Modified MODIS fluorescence line head product to improve image interpretation for red tide monitoring in the eastern Gulf of Mexico,” J. Appl. Remote Sens. 11 (1), 012003 (2016). https://doi.org/1117/1.JRS.11.012003
G. S. Karabashev, “Spectral indexation of pixels of MODIS sea surface images for detecting inconstancy of phytopigment composition in water,” Oceanologia 63 (4), 482–496 (2021). https://doi.org/10.1016/j.oceano.2021.06.001
G. S. Karabashev, “Spectral indexing of MODIS-image pixels to reveal the variability in the phytopigment composition in the sea under the influence of mesoscale water dynamics,” Oceanology 61 (6), 861–871 (2021). https://doi.org/10.1134/S0001437021060242
C. D. Mobley, “Radiative transfer in the ocean,” in Encyclopedia of Ocean Sciences, Ed. by J. H. Steele, K. K. Turekian, and S. A. Thorpe, 2nd ed. (Academic Press, London, 2011), Vol. 4, pp. 619–628.
C. D. Mobley, D. Stramski, W. P. Bisset, and E. Boss, “Optical modeling of ocean water. Is the Case 1–Case 2 classification still useful?,” Oceanography 17 (2), 60–67 (2004).
A. Morel, “Optical modeling of the upper ocean in relation to its biogeneous matter content (case 1 waters),” J. Geophys. Res. 93 (C9), 10749–10768 (1988).
A. Morel, B. Gentili, M. Chamu, and J. Ras, “Bio-optical properties of high chlorophyll case 1 waters and of yellow-substance-dominated case 2 waters,” Deep Sea Res. 53 (9), 1439–1459 (2006). https://doi.org/10.1016/j.dsr.2006.07.007
Uz. S. Schollaert, G. E. Kim, A. Mannino, et al., “Developing a community of practice for applied uses of future PACE data to address marine food security challenges,” Front. Earth Sci. 7, 283 (2019). https://doi.org/10.3389/feart.2019.00283
S. Sheberstov and E. Lukyanova, “A system for acquisition, processing and storage of satellite and field biooptical data,” in Proc. IV Int. Conf.: Current Problems in Optics of Natural Waters, Nizhny Novgorod, September 11–15, 2007, pp. 179–183.
D. W. Waugh, E. R. Abraham, and M. M. Bowen, “Spatial variations of stirring in the surface ocean: A case study of the Tasman Sea,” J. Phys. Oceanogr. 36, 526–542 (2006).
B. Wozniak and J. Dera, Light Absorption in Sea Water (Springer, New York, 2007).
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Karabashev, G.S. Effects of Mesoscale Mixing on Phytopigment Determinations in the Photic Zone from Multispectral Ocean Color Data (The Case of the Tasman Sea). Oceanology 63, 35–44 (2023). https://doi.org/10.1134/S0001437023010046
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DOI: https://doi.org/10.1134/S0001437023010046