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Mooring locations in Mississippi Sound, between Ship and Horn Islands. The background is a true color Planet nanosatellite image collected at 1600 UTC on 3/25/2018.
Source publication
Optically-active constituents vary over short time and space scales in coastal waters, and they are impacted by a variety of complex, inter-related forcing processes. As part of the Integrated Coastal Bio-Optical Dynamics (ICoBOD) project, we conducted a field campaign in Mississippi Sound in the northern Gulf of Mexico during spring 2018 to examin...
Citations
... In March and April of 2018, a variety of data were collected in the Mississippi Sound in and around an ocean front. A previous publication discussed the breadth of instrumentation used to collect data during these acquisitions and provided context and rationale for the study [1]. Hyperspectral remote sensing reflectance data, collected from airborne and Unmanned Aerial Vehicle (UAV) platforms, were included in this dataset. ...
... The coastal zone is the interface between land and the open ocean, and it is impacted by many processes, such as blooms, river discharge, and sediment resuspension. The previous publication examined the impact of tides and atmospheric fronts on bio-optical variability, including the development and decay of the nepheloid layers, using mooring datasets and compared them with models [1]. Here, we expand that work to use remote sensing and modeling to further examine fine-scale coastal variability. ...
... During this data collection activity on 04/05/18, personnel in the aircraft that housed thermal and reflectance sensors observed a front created during flood tide from the south and northerly winds, as shown in Figure 2b. The vessel was then directed to the front, where subsequently uranine and rhodamine dye were deployed to aid in the understanding of mixing and subduction processes [1]. Radiometer readings were taken in and around the front. ...
Bio-optical and physical measurements were collected in the Mississippi Sound (Northern Gulf of Mexico) during the spring of 2018 as part of the Integrated Coastal Bio-Optical Dynamics project. The goal was to examine the impact of atmospheric and tidal fronts on fine-scale physical and bio-optical property distributions in a shallow, dynamic, coastal environment. During a 25-day experiment, eight moorings were deployed in the vicinity of a frontal zone. For a one-week period in the middle of the mooring deployment, focused ship sampling was conducted with aircraft and unmanned aerial vehicle overflights, acquiring hyperspectral optical and thermal data. The personnel in the aircraft located visible color fronts indicating the convergence of two water masses and directed the ship to the front. Dye releases were performed on opposite sides of a front, and coincident aircraft and unmanned aerial vehicle overflights were collected to facilitate visualization of advection/mixing/dispersion processes. Radiometric calibration of the optical hyperspectral sensor was performed. Empirical Line Calibration was also performed to atmospherically correct the aircraft imagery using in situ remote sensing reflectance measurements as calibration sources. Bio-optical properties were subsequently derived from the atmospherically corrected aircraft and unmanned aerial vehicle imagery using the Naval Research Laboratory Automated Processing System.
... The variability of in-water bio-optical properties has been shown to be associated with specific environmental and biological conditions [1,2]. On the diurnal time scale, physical factors influencing such variability include tides, fronts, river discharge, ocean circulation, wind-driven mixing, etc. [3]. The bio-optical properties of water mass change along with the growth and decay of phytoplankton blooms, upwelling and downwelling, particle settling, and resuspension events [4,5]. ...
Ocean processes that can influence rapidly changing ocean color include water-mass movement and bio-optical property changes in the water parcel. Traditionally, diurnal variability of bio-optical properties relies on daily time series at fixed locations by satellite sensors or in situ observations. There is a lack of an effective way to observe diurnal variation of bio-optical properties in a moving water parcel on a large scale. In this paper, we propose a new method to acquire diurnal variation of bio-optical properties in a moving water parcel. The novel approach integrates drifting buoy data and GOCI data. The movement of surface current was tracked by a drifting buoy, and its spatiotemporally matching bio-optical properties were obtained via the GOCI data. The results in the Yellow and East China seas during the summers of 2012 and 2013 show that the variation of time series following the movement of water parcel was obviously different from that obtained at fixed locations. The hourly differences of the former are 15.7% and 16.3% smaller than those of the latter for Chl a and total suspended sediment (TSS), respectively. The value of ag440 was more stable within the moving water parcel than in the fixed location. Our approach provides a simple and feasible way for observing diurnal variability of bio-optical properties in a moving surface water parcel.
