Sources, sinks and resuspension of suspended particulate matter in the eastern English Channel

Velegrakis, Adonis F.; Michel, Dominik; Collins, Michael B.; Lafite, Robert; Oikonomou, Emmanouil; Dupont, Jean-Paul; Huault, Marie-Françoise; Lecouturier, M.; Salomon, Jean-Claude; Bishop, Christine A.

doi:10.1016/s0278-4343(99)00047-3

Cited by 30 publications

(22 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In this study, we investigated the PSD spatial distribution of the study area based on in situ laser diffraction measurements during November 2013. Note that the observation stations were actually investigated on different dates and time during a month, and so some factors such as tidal current, waves and turbulence [25][26][27][28], might show a certain impact on temporal variability of PSD. However, it is very difficult to do synchronous observation on all these stations in the investigated water areas, which limits the plot of spatial distribution in a rigorously simultaneous manner.…”

Section: Discussionmentioning

confidence: 99%

Variability of Particle Size Distributions in the Bohai Sea and the Yellow Sea

Qiu

Sun

et al. 2016

Remote Sensing

View full text Add to dashboard Cite

Particle size distribution (PSD) is an important parameter that is relevant to many aspects of marine ecosystems, such as phytoplankton functional types, optical absorption and scattering from particulates, sediment fluxes, and carbon export. However, only a handful of studies have documented the PSD variability in different regions. Here, we investigate the PSD properties and variability in two shallow and semi-enclosed seas (the Bohai Sea (BS) and Yellow Sea (YS)), using in situ laser diffraction measurements (LISST-100X Type C) and other measurements at 79 stations in November 2013. The results show large variability in particle concentrations (in both volume and number concentrations), with volume concentrations varying by 57-fold. The median particle diameter (D v 50 ) from each of the water samples also covers a large range (22.4-307.0 µm) and has an irregular statistical distribution, indicating complexity in the PSD. The PSD slopes (2.7-4.5), estimated from a power-law model, cover nearly the entire range reported previously for natural waters. Small mineral particles (with large PSD slopes) are characteristic of near-shore waters prone to sediment resuspension by winds and tides, while large biological particles (with small PSD slopes) dominate the total suspended particulates for waters away from the coast. For the BS and YS, this study provides the first report on the properties and spatial variability of the PSD, which may influence the optical properties of the ocean surface and remote sensing algorithms that are based on estimations of particle concentrations and sizes.

show abstract

Section: Discussionmentioning

confidence: 99%

Variability of Particle Size Distributions in the Bohai Sea and the Yellow Sea

Qiu

Sun

et al. 2016

Remote Sensing

View full text Add to dashboard Cite

show abstract

“…8. Despite the curious discrepancy at this station, with high SPM levels measured in-situ in summertime when lower concentrations are expected following the decrease in the resuspension induced by the waves in the English Channel (Velegrakis et al, 1999), the overall adjustment is excellent and 714 F. Gohin: Annual Cycles of Chlorophyll-a and Turbidity the correlation coefficient is high. However, we have only 8 stations and this enhances the interest for turbidity to assess the capacity of the ocean colour sensors to monitor water clarity.…”

Section: The Annual Cycle Of Non-algal Spm Observed From Space and Inmentioning

confidence: 91%

Annual cycles of chlorophyll-<i>a</i>, non-algal suspended particulate matter, and turbidity observed from space and in-situ in coastal waters

2011

View full text Add to dashboard Cite

Abstract. Sea surface temperature, chlorophyll, and turbidity are three variables of the coastal environment commonly measured by monitoring networks. The observation networks are often based on coastal stations, which do not provide a sufficient coverage to validate the model outputs or to be used in assimilation over the continental shelf. Conversely, the products derived from satellite reflectance generally show a decreasing quality shoreward, and an assessment of the limitation of these data is required. The annual cycle, mean, and percentile 90 of the chlorophyll concentration derived from MERIS/ESA and MODIS/NASA data processed with a dedicated algorithm have been compared to in-situ observations at twenty-six selected stations from the Mediterranean Sea to the North Sea. Keeping in mind the validation, the forcing, or the assimilation in hydrological, sediment-transport, or ecological models, the non-algal Suspended Particulate Matter (SPM) is also a parameter which is expected from the satellite imagery. However, the monitoring networks measure essentially the turbidity and a consistency between chlorophyll, representative of the phytoplankton biomass, non-algal SPM, and turbidity is required. In this study, we derive the satellite turbidity from chlorophyll and non-algal SPM with a common formula applied to in-situ or satellite observations. The distribution of the satellite-derived turbidity exhibits the same main statistical characteristics as those measured in-situ, which satisfies the first condition to monitor the long-term changes or the largescale spatial variation over the continental shelf and along the shore. For the first time, climatologies of turbidity, so useful for mapping the environment of the benthic habitats, are proposed from space on areas as different as the southern North Sea or the western Mediterranean Sea, with validation at coastal stations.

show abstract

“…Tides in the Eastern English Channel are semi-diurnal, with a period of 12:24 h, and represent the dominant hydrodynamic forces. The tidal range can reach ten meters during spring tides with strong associated tidal current velocities going up to 1.7 m s −1 near the bottom (Velegrakis [47]). …”

Section: Field Sitesmentioning

confidence: 99%

Bedload transport for heterogeneous sediments

Durafour

Jarno

Bot³

et al. 2014

Environ Fluid Mech

View full text Add to dashboard Cite

International audienceA large panel of instruments was deployed in the Eastern English Channel tomeasure the evolution of bedload fluxes during a tidal cycle for two different sites. The firstone was characterized by a sandy bed with a low dispersion in size while the other studysite implied graded sediments with grain sizes ranging from fine sands to granules. Thein situ results obtained were compared with predictions of total bedload fluxes by classicalmodels.Agoodagreementwasfoundforhomogeneoussedimentswiththeseformulas.Inthecase of size heterogeneous sediments, a fractionwise approach, involving a hiding-exposurecoefficientandahindrancefactor,providedbetterpredictionsofbedloadfluxes,butstillsomediscrepancies were noticed. Present results revealed that the consideration of particle shapein formulas through the circularity index enhanced the estimations of bedload transport rates.A new adjustment of Wu et al.’s (J Hydraul Res 38:427–434, 2000) formula was proposed and a very good agreement was obtained between the measured and predicted values

show abstract

Sources, sinks and resuspension of suspended particulate matter in the eastern English Channel

Cited by 30 publications

References 41 publications

Variability of Particle Size Distributions in the Bohai Sea and the Yellow Sea

Variability of Particle Size Distributions in the Bohai Sea and the Yellow Sea

Annual cycles of chlorophyll-<i>a</i>, non-algal suspended particulate matter, and turbidity observed from space and in-situ in coastal waters

Bedload transport for heterogeneous sediments

Contact Info

Product

Resources

About

Sources, sinks and resuspension of suspended particulate matter in the eastern English Channel

Cited by 30 publications

References 41 publications

Variability of Particle Size Distributions in the Bohai Sea and the Yellow Sea

Variability of Particle Size Distributions in the Bohai Sea and the Yellow Sea

Annual cycles of chlorophyll-&lt;i&gt;a&lt;/i&gt;, non-algal suspended particulate matter, and turbidity observed from space and in-situ in coastal waters

Bedload transport for heterogeneous sediments

Contact Info

Product

Resources

About

Annual cycles of chlorophyll-<i>a</i>, non-algal suspended particulate matter, and turbidity observed from space and in-situ in coastal waters