Laboratory measurements of remote sensing reflectance of selected phytoplankton species from the Baltic Sea

Soja‐Woźniak, Monika; Darecki, Mirosław; Wojtasiewicz, Bożena; Bradtke, Katarzyna

doi:10.1016/j.oceano.2017.08.001

Cited by 19 publications

(15 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The challenge with this reductionist approach is that the optical calculations require the concentration‐specific optical properties of each of the variables it represents. This type of data is common and available for benthic substrates (Roelfsema & Phinn, ) and the pigments contained within phytoplankton species (Soja‐Woźniak et al, ) but is much rarer for single mineral suspensions (exception is Stramski et al, ). Further complicating the optical properties of mineral grain mixtures is that both the mineralogy (carbonate, quartz, and illite) and the PSD are likely to vary between different natural environments, and during time at individual locations.…”

Section: Discussionmentioning

confidence: 99%

“…Inherent optical properties, and the concentration of optically significant constituents, can be derived from remote-sensing reflectance; however, in optically complex waters global empirical and globally parameterized semianalytical remotely sensed algorithms tend to fail (Darecki & Stramski, 2004;Kratzer et al, 2008;Woźniak et al, 2014;Qin et al, 2007). A better understanding of coastal bio-optical properties is crucial to the accurate estimation of the seawater components from optical remote sensing (Aurin & Dierssen, 2012;Babin et al, 2003;Miller et al, 2005;Odermatt et al, 2012;Reynolds et al, 2001;Sathyendranath et al, 1989Sathyendranath et al, , 2016Soja-Woźniak et al, 2017) and for parameterizing biogeochemical models (Baird, Adams, et al, 2016).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Particulate Backscattering Ratio as an Indicator of Changing Particle Composition in Coastal Waters: Observations From Great Barrier Reef Waters

et al. 2019

View full text Add to dashboard Cite

Particle scattering is an important process that determines both the light penetration through the water column and water‐leaving light. Backscattering, in combination with absorption, determines the remote‐sensing reflectance that is used in ocean color algorithms. Additionally, the wavelength dependence of the backscattering ratio can be related to the particle composition in seawater. Here, we examine the magnitude and the spectral behavior of the backscattering ratio against other bio‐optical properties based on a comprehensive set of continuous measurements collected in coastal waters of the Great Barrier Reef over 3 years. The site is located offshore of a major river, and close to the cross‐shelf transition of bottom sediments from terrigenous muds to marine carbonates. The backscattering ratio measured at 650 nm clearly clustered the data into two types. Type 1, which we identified as terrigenous mud with a low organic fraction, is characterized by backscattering ratio below 0.011 with a mean value of 0.005. Type 2, which we identified as marine carbonate with a higher organic fraction, has backscattering ratio above 0.011 with a mean value of 0.02. Within 3 years, study site was exposed to type 1‐dominated particles 13% of the time, and type 2 87%. The observed changes in the backscattering ratio at this one coastal site are as large as the variability seen throughout the global ocean. This work provides a better understanding of processes determining the optical characteristics and insights into optical parameterizations that can be used in process‐based optical modeling of the Great Barrier Reef.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Particulate Backscattering Ratio as an Indicator of Changing Particle Composition in Coastal Waters: Observations From Great Barrier Reef Waters

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Xi et al 2017) as well as direct measurements (e.g. Soja-Wozniak et al 2018) made on the main phytoplankton groups (Chlorophyta, Cyanophyta, Haptophyta, Dinophyta, Cryptophyta and Heterkontophyta) suggest that absorption by these phytoplankton groups is strongest between ~520 and 650 nm. Gut phytoplankton may therefore contribute to part of the absorption feature we measured between 460 and 590 nm.…”

Section: Discussionmentioning

confidence: 99%

Experimental determination of reflectance spectra of Antarctic krill (Euphausia superba) in the Scotia Sea

et al. 2021

View full text Add to dashboard Cite

Antarctic krill are the dominant metazoan in the Southern Ocean in terms of biomass; however, their wide and patchy distribution means that estimates of their biomass are still uncertain. Most currently employed methods do not sample the upper surface layers, yet historical records indicate that large surface swarms can change the water colour. Ocean colour satellites are able to measure the surface ocean synoptically and should theoretically provide a means for detecting and measuring surface krill swarms. Before we can assess the feasibility of remote detection, more must be known about the reflectance spectra of krill. Here, we measure the reflectance spectral signature of Antarctic krill collected in situ from the Scotia Sea and compare it to that of in situ water. Using a spectroradiometer, we measure a strong absorption feature between 500 and 550 nm, which corresponds to the pigment astaxanthin, and high reflectance in the 600–700 nm range due to the krill's red colouration. We find that the spectra of seawater containing krill is significantly different from seawater only. We conclude that it is tractable to detect high-density swarms of krill remotely using platforms such as optical satellites and unmanned aerial vehicles, and further steps to carry out ground-truthing campaigns are now warranted.

show abstract

“…In this study, we took a step forward from modeling to in situ experiment in a unique attempt to measure the R rs of dispersed oil pollution in open sea conditions. We applied the idea of a comparative study between natural seawater and seawater polluted by oil droplets, as commonly practiced in ocean optics, e.g., on phytoplankton species [67] or other aquatic vegetation [68].…”

Section: Measurements Of the Remote Sensing Reflectancementioning

confidence: 99%

Influence of Dispersed Oil on the Remote Sensing Reflectance—Field Experiment in the Baltic Sea

Haule

Toczek

Borzycka

et al. 2021

Sensors

Self Cite

View full text Add to dashboard Cite

Remote sensing techniques currently used to detect oil spills have not yet demonstrated their applicability to dispersed forms of oil. However, oil droplets dispersed in seawater are known to modify the local optical properties and, consequently, the upwelling light flux. Theoretically possible, passive remote detection of oil droplets was never tested in the offshore conditions. This study presents a field experiment which demonstrates the capability of commercially available sensors to detect significant changes in the remote sensing reflectance Rrs of seawater polluted by six types of dispersed oils (two crude oils, cylinder lubricant, biodiesel, and two marine gear lubricants). The experiment was based on the comparison of the upwelling radiance Lu measured in a transparent tank floating in full immersion in seawater in the Southern Baltic Sea. The tank was first filled with natural seawater and then polluted by dispersed oils in five consecutive concentrations of 1–15 ppm. After addition of dispersed oils, spectra of Rrs noticeably increased and the maximal increase varied from 40% to over three-fold at the highest oil droplet concentration. Moreover, the most affected Rrs band ratios and band differences were analyzed and are discussed in the context of future construction of algorithms for dispersed oil detection.

show abstract

Laboratory measurements of remote sensing reflectance of selected phytoplankton species from the Baltic Sea

Cited by 19 publications

References 44 publications

Particulate Backscattering Ratio as an Indicator of Changing Particle Composition in Coastal Waters: Observations From Great Barrier Reef Waters

Particulate Backscattering Ratio as an Indicator of Changing Particle Composition in Coastal Waters: Observations From Great Barrier Reef Waters

Experimental determination of reflectance spectra of Antarctic krill (Euphausia superba) in the Scotia Sea

Influence of Dispersed Oil on the Remote Sensing Reflectance—Field Experiment in the Baltic Sea

Contact Info

Product

Resources

About