Fluorescence component in the reflectance spectra from coastal waters. Dependence on water composition

A. Gilerson; J. Zhou; S. Hlaing; I. Ioannou; J. Schalles; B. Gross; F. Moshary; S. Ahmed

doi:10.1364/oe.15.015702

Using Optical Water Types to Monitor Changes in Optically Complex Inland and Coastal Waters

Remote Sensing ◽

10.3390/rs11192297 ◽

2019 ◽

Vol 11 (19) ◽

pp. 2297 ◽

Cited By ~ 6

Author(s):

Kristi Uudeberg ◽

Ilmar Ansko ◽

Getter Põru ◽

Ave Ansper ◽

Anu Reinart

Keyword(s):

Remote Sensing ◽

Coastal Waters ◽

Atmospheric Correction ◽

Suspended Sediments ◽

Reflectance Spectra ◽

Water Type ◽

Colored Dissolved Organic Matter ◽

Water Color ◽

Sentinel 2

The European Space Agency’s Copernicus satellites Sentinel-2 and Sentinel-3 provide observations with high spectral, spatial, and temporal resolution which can be used to monitor inland and coastal waters. Such waters are optically complex, and the water color may vary from completely clear to dark brown. The main factors influencing water color are colored dissolved organic matter, phytoplankton, and suspended sediments. Recently, there has been a growing interest in the use of the optical water type (OWT) classification in the remote sensing of ocean color. Such classification helps to clarify relationships between different properties inside a certain class and quantify variation between classes. In this study, we present a new OWT classification based on the in situ measurements of reflectance spectra for boreal region lakes and coastal areas without extreme optical conditions. This classification divides waters into five OWT (Clear, Moderate, Turbid, Very Turbid, and Brown) and shows that different OWTs have different remote sensing reflectance spectra and that each OWT is associated with a specific bio-optical condition. Developed OWTs are distinguishable by both the MultiSpectral Instrument (MSI) and the Ocean and Land Color Instrument (OLCI) sensors, and the accuracy of the OWT assignment was 95% for both the MSI and OLCI bands. To determine OWT from MSI images, we tested different atmospheric correction (AC) processors, namely ACOLITE, C2RCC, POLYMER, and Sen2Cor and for OLCI images, we tested AC processors ALTNNA, C2RCC, and L2. The C2RCC AC processor was the most accurate and reliable for use with MSI and OLCI images to estimate OWTs.

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Manganese content records seasonal upwelling in Lake Tanganyika mussels

Biogeosciences ◽

10.5194/bg-4-195-2007 ◽

2007 ◽

Vol 4 (2) ◽

pp. 195-203 ◽

Cited By ~ 24

Author(s):

D. Langlet ◽

L. Y. Alleman ◽

P.-D. Plisnier ◽

H. Hughes ◽

L. André

Keyword(s):

Surface Waters ◽

Coastal Waters ◽

Lake Tanganyika ◽

Manganese Content ◽

Monsoon Climate ◽

Freshwater Bivalve ◽

Water Composition ◽

Deep Waters ◽

Crater Size ◽

Icp Ms

Abstract. Biogenic productivity of Lake Tanganyika is highly dependent on seasonal upwellings of cold, oxygen-depleted, nutrient-rich deep waters. We investigated the shell of freshwater bivalve Pleiodon spekii as a geochemical archive of these periodic hydrological changes tuned by the monsoon regime. The results of a three-year-long limnological and geochemical survey of the coastal waters performed on the dissolved and particulate fractions were compared to LA-ICP-MS profiles of Mn in five aragonitic shells from the same lake location. Three shells present very similar Mn/Ca profiles dominated by a peak that matched the concomitant increase of Mn and chlorophyll a in surface waters during the 2002 upwelling, while a shell collected during 2003 dry season detect both 2002 and 2003 upwelling events. Larger shells showing an extremely reduced growth display more than 8 Mn/Ca peaks suggesting at least an 8-year-record of seasonal changes in water composition. We postulate that Mn/Ca in shells record the conjunction of an increase of biological activity with supplied of dissolved Mn and nutriments in coastal waters, resulting in an enhanced assimilation of biogenic Mn-rich particles. By combining the most recent generation of laser ablation system and the powerful High Resolution ICP-MS, the spatial resolution could be improved down to 5 to 10 µm crater size and end up in a better constrain of the relative variations of the annual Mn peaks. Such an approach on P. spekii from Lake Tanganyika has definitively a great potential to provide recent and past records on primary productivity associated with the monsoon climate system.

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Comparison of aerosol models from the Ocean Color satellite sensors and AERONET-OC and their impact on reflectance spectra in coastal waters

Ocean Sensing and Monitoring X ◽

10.1117/12.2309581 ◽

2018 ◽

Author(s):

Eder Herrera ◽

Yaron Klein ◽

Robert Foster ◽

Barry Gross ◽

Robert A. Arnone ◽

...

Keyword(s):

Coastal Waters ◽

Ocean Color ◽

Reflectance Spectra ◽

Satellite Sensors

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Fluorescence Component in the Reflectance Spectra from Coastal Waters. II. Performance of retrieval algorithms

Optics Express ◽

10.1364/oe.16.002446 ◽

2008 ◽

Vol 16 (4) ◽

pp. 2446 ◽

Cited By ~ 27

Author(s):

A. Gilerson ◽

J. Zhou ◽

S. Hlaing ◽

I. Ioannou ◽

B. Gross ◽

...

Keyword(s):

Coastal Waters ◽

Reflectance Spectra ◽

Retrieval Algorithms

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Mn seasonal upwellings recorded in Lake Tanganyika mussels

Biogeosciences Discussions ◽

10.5194/bgd-3-1453-2006 ◽

2006 ◽

Vol 3 (5) ◽

pp. 1453-1471 ◽

Cited By ~ 6

Author(s):

D. Langlet ◽

L. Y. Alleman ◽

P.-D. Plisnier ◽

H. Hughes ◽

L. André

Keyword(s):

Laser Ablation ◽

Surface Waters ◽

Coastal Waters ◽

Seasonal Changes ◽

Lake Tanganyika ◽

Freshwater Bivalve ◽

Water Composition ◽

Deep Waters ◽

Hydrological Changes ◽

Icp Ms

Abstract. Biogenic productivity of Lake Tanganyika is highly dependent on seasonal upwellings of anoxic deep waters. We investigated the shell of freshwater bivalve Pleiodon spekii as a geochemical archive of these periodic hydrological changes tuned by the monsoon regime. The results of a 2-years-long geochemical survey of the coastal waters performed on the dissolved and particulate fractions were put in perspective against laser ablation ICP-MS profiles of Mn in five aragonitic shells from the same lake location. Skeletal Mn profiles in 3 shells are very similar and dominated by episodic peaks that matched the Mn increase recorded in surface waters during the 2002 upwelling, while a shell collected during 2003 dry season detect both 2002 and 2003 upwelling events. Larger shells showing an extremely reduced growth display more than 8Mn peaks suggesting at least an 8 years record of seasonal changes in water composition.

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