•A new algorithm was developed to automate satellite-derived coastal bathymetry.•Automation included assessment of chlorophyll concentration and deglinting.•RMSE of 1.95 m from 0 to 15 m depth was ...achieved.•This method produces wall-to-wall bathymetry at 138 km2min-1.
Accurate and up-to-date maps of coastal bathymetry are fundamental for coastal resource management, commercial and military navigation, and aquaculture, among many applications. Existing methods for bathymetry mapping require intensive and costly field surveys or targeted aerial captures, neither of which are easily or affordably replicated for repeat mapping and change monitoring. Satellite-derived bathymetry (SDB), however, offers the potential to map shallow water bodies repeatedly and efficiently with high spatial and temporal resolution (i.e., daily-weekly at 5 m or better). One challenge to large-scale implementation of SDB lies in the automated derivation of inherent water column properties such that they may be accurately compensated for across a variety of depth and substrate conditions. Here we present an algorithm that leverages WorldView (Maxar/Digital GlobeTM) satellite imagery to map the entire 3700 km2 Florida Keys (USA) island chain at 2-meter resolution without the need for any in-situ data collections. Preprocessing included radiometric calibration, atmospheric correction, automated deglinting, and automated detection of optically deep water, which was then used to estimate chlorophyll-a concentration assuming that the study area is primarily comprised of Case-I water (i.e., those where the optical signal is dominated by water, Chlorophyll-a in phytoplankton, and properties that vary in proportion to Chlorophyll-a concentration). Estimating Chlorophyll-a concentration allowed us to calculate the appropriate tuning coefficients used in a spectral band ratio equation for estimating bathymetry. The entire process was fully automated from ingestion of Level-1B image to bathymetry raster output. Mapping the Florida Keys from Key Largo to Key West required 34 WorldView images and was completed in approximately 27 min for an average processing time of 47 s per image using a single GPU core (i.e., supercomputing resources were not needed). After combining the products (mosaicking) in ArcMap, the wall-to-wall bathymetry map was validated against a LiDAR-derived bathymetry model with over 600,000 points; results show an RMSE of 1.95 m over depths from 0 to 15 m.
The cross-shelf advection of coastal waters into the deep Gulf of Mexico is important for the transport of nutrients or potential pollutants. Twenty years of ocean color satellite imagery document ...such cross-shelf transport events via three export pathways in the Gulf of Mexico: from the Campeche Bank toward the central Gulf, from the Campeche Bank toward the Florida Straits, and from the Mississippi Delta to the Florida Straits. A catalog of these events was created based on the visual examination of 7280 daily satellite images. Water transport from the Campeche Bank to the central Gulf occurred frequently and with no seasonal pattern. Transport from Campeche Bank to the Florida Straits occurred episodically, when the Loop Current was retracted. Four such episodes were identified, between about December and June, in 2002, 2009, 2016, and 2017, each lasting ~3 months. Movement of Mississippi River water to the Florida Straits was more frequent and showed near seasonal occurrence, when the Loop Current was extended, while the Mississippi River discharge seems to play only a secondary role. Eight such episodes were identified—in 1999, 2000, 2003, 2004, 2006, 2011, 2014, and 2015—each lasting ~3 months during summer. The 2015 episode lasted 5 months.
Management of coastal and marine natural resources presents a number of challenges as a growing global population and a changing climate require us to find better strategies to conserve the resources ...on which our health, economy, and overall well-being depend. To evaluate the status and trends in changing coastal resources over larger areas, managers in government agencies and private stakeholders around the world have increasingly turned to remote sensing technologies. A surge in collaborative and innovative efforts between resource managers, academic researchers, and industry partners is becoming increasingly vital to keep pace with evolving changes of our natural resources. Synoptic capabilities of remote sensing techniques allow assessments that are impossible to do with traditional methods. Sixty years of remote sensing research have paved the way for resource management applications, but uncertainties regarding the use of this technology have hampered its use in management fields. Here we review examples of remote sensing applications in the sectors of coral reefs, wetlands, water quality, public health, and fisheries and aquaculture that have successfully contributed to management and decision-making goals.
African American prostate cancer survivors experience post-treatment decisional regret more often than European Americans, which can lead to negative long-term effects on quality of life. A prominent ...driver of health-related decision-making is emotion, yet little work has examined the impact emotions may have on decisional regret. The goal of this study was to explore experiences, perceptions, and emotions of prostate cancer survivors in relation to their diagnostic and treatment decision-making processes, prostate cancer treatment, and outcomes. Additionally, we sought to identify factors that might explain differences in prostate cancer outcomes between African and European Americans.
This mixed-methods study utilized a convergent parallel design, in which quantitative and qualitative data were collected simultaneously and then integrated to more robustly explain relationships between variables. Survivors were eligible for the study if they had been previously diagnosed with localized prostate cancer and were no more than six months post-treatment. The study was guided by the Risk as Feelings Model, which predicts the relationship between emotion and cognition in high-risk decision-making.
No men experienced decisional regret following treatment, even if they experienced side effects. While all men reported being surprised about their prostate cancer diagnosis, strong negative emotions were more common among men under 65. Family support and spirituality appeared to mitigate negative emotions. Perceived authenticity of provider communication was the most influential mediator in men's decision-making and positive perceptions of their outcomes.
To mitigate the impact emotional responses have on decision-making and post-treatment regret, providers should explore alternate therapies (e.g. counseling for men diagnosed with prostate cancer at a young age) and include family members in prostate cancer treatment discussions. Most importantly, providers should be aware of the importance of quality communication on men's cognitive and emotional processes and their perceptions of treatment outcomes.
Coastal water-quality is both a primary driver and also a consequence of coastal ecosystem health. Turbidity, a measure of dissolved and particulate water-quality matter, is a proxy for water ...quality, and varies on daily to interannual periods. Turbidity is influenced by a variety of factors, including algal particles, colored dissolved organic matter, and suspended sediments. Identifying which factors drive trends and extreme events in turbidity in an estuary helps environmental managers and decision makers plan for and mitigate against water-quality issues. Efforts to do so on large spatial scales have been hampered due to limitations of turbidity data, including coarse and irregular temporal resolution and poor spatial coverage. We addressed these issues by deriving a proxy for turbidity using ocean color satellite products for 11 Gulf of Mexico estuaries from 2000 to 2014 on weekly, monthly, seasonal, and annual time-steps. Drivers were identified using Akaike’s Information Criterion and multiple regressions to model turbidity against precipitation, wind speed, U and V wind vectors, river discharge, water level, and El Nino Southern Oscillation and North Atlantic Oscillation climate indices. Turbidity variability was best explained by wind speed across estuaries for both time-series and extreme turbidity events, although more dynamic patterns were found between estuaries over various time steps.
In recent years, optical sensors for tracking neural activity have been developed and offer great utility. However, developing microscopy techniques that have several kHz bandwidth necessary to ...reliably capture optically reported action potentials (APs) at multiple locations in parallel remains a significant challenge. To our knowledge, we describe a novel microscope optimized to measure spatially distributed optical signals with submillisecond and near diffraction-limit resolution. Our design uses a spatial light modulator to generate patterned illumination to simultaneously excite multiple user-defined targets. A galvanometer driven mirror in the emission path streaks the fluorescence emanating from each excitation point during the camera exposure, using unused camera pixels to capture time varying fluorescence at rates that are ∼1000 times faster than the camera’s native frame rate. We demonstrate that this approach is capable of recording Ca2+ transients resulting from APs in neurons labeled with the Ca2+ sensor Oregon Green Bapta-1 (OGB-1), and can localize the timing of these events with millisecond resolution. Furthermore, optically reported APs can be detected with the voltage sensitive dye DiO-DPA in multiple locations within a neuron with a signal/noise ratio up to ∼40, resolving delays in arrival time along dendrites. Thus, the microscope provides a powerful tool for photometric measurements of dynamics requiring submillisecond sampling at multiple locations.
Environmental conditions influence fecal indicator bacteria (FIB) levels, which are routinely used to characterize recreational water quality. This study examined 15 years of environmental and FIB ...data at Puntarenas and Jacó beach, Costa Rica. FIB relationships with sea level, wave height, precipitation, direct normal irradiance (DNI), wind, and turbidity were analyzed. Pearson's correlations identified lags between 24 and 96 h among environmental parameters and FIB. Multiple linear regression models composed of environmental parameters explained 24% and 27% of fecal coliforms and enterococci variability in Jacó, respectively. Puntarenas’s models explained 17–26% of fecal coliforms and 12–18% enterococci variability. Precipitation, sea level anomalies, and wave height most frequently explained FIB variability. Hypothesis testing often identified significant differences in precipitation, wave height, daily sea level anomalies, and maximum sea level 24 h prior between days with and without FIB threshold exceedance. Unexpected FIB interactions with DNI, sea level, and turbidity highlight the importance of future investigations.
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•Environmental parameters explained 12 to 27% of FIB geometric mean variability.•Precipitation, sea level anomalies, and wave height most frequently explained FIB variability.•Higher precipitation was associated with exceedance of FIB thresholds.•Greater wave height was associated with exceedance of FIB thresholds.•Greater maximum sea level 24 h prior was associated with exceedance of FIB thresholds.
The 2017–2027 National Academies' Decadal Survey, Thriving on Our Changing Planet, recommended Surface Biology and Geology (SBG) as a “Designated Targeted Observable” (DO). The SBG DO is based on the ...need for capabilities to acquire global, high spatial resolution, visible to shortwave infrared (VSWIR; 380–2500 nm; ~30 m pixel resolution) hyperspectral (imaging spectroscopy) and multispectral midwave and thermal infrared (MWIR: 3–5 μm; TIR: 8–12 μm; ~60 m pixel resolution) measurements with sub-monthly temporal revisits over terrestrial, freshwater, and coastal marine habitats. To address the various mission design needs, an SBG Algorithms Working Group of multidisciplinary researchers has been formed to review and evaluate the algorithms applicable to the SBG DO across a wide range of Earth science disciplines, including terrestrial and aquatic ecology, atmospheric science, geology, and hydrology. Here, we summarize current state-of-the-practice VSWIR and TIR algorithms that use airborne or orbital spectral imaging observations to address the SBG DO priorities identified by the Decadal Survey: (i) terrestrial vegetation physiology, functional traits, and health; (ii) inland and coastal aquatic ecosystems physiology, functional traits, and health; (iii) snow and ice accumulation, melting, and albedo; (iv) active surface composition (eruptions, landslides, evolving landscapes, hazard risks); (v) effects of changing land use on surface energy, water, momentum, and carbon fluxes; and (vi) managing agriculture, natural habitats, water use/quality, and urban development. We review existing algorithms in the following categories: snow/ice, aquatic environments, geology, and terrestrial vegetation, and summarize the community-state-of-practice in each category. This effort synthesizes the findings of more than 130 scientists.
•The 2017 Decadal Survey recommended Surface Biology and Geology mission•Visible to shortwave infrared hyperspectral and multi-band thermal data•Global high resolution measurements at sub-monthly temporal resolution•Applications in snow/ice, aquatic environment, geology, and terrestrial vegetation•We review existing relevant algorithms and community-state-of-practice
Land cover changes in the Tampa Bay watershed (Florida) over the past four decades were examined along with precipitation and wind observations to help understand causes of long-term changes in ...turbidity and chlorophyll concentration within the Tampa Bay estuary. Water quality showed a statistically significant relationship to land cover fraction in the watershed compared to long-term precipitation or wind stress. Redundancy Analyses with Akaike's Information Criterion and non-parametric multiple regressions determined that turbidity and chlorophyll concentration decreased bay-wide from 1974-2012 with increased developed land fraction (R
2
> 0.75, p-value < 0.05). Various segments of the estuary showed different significant responses to developed land (R
2
> 0.75, p-value < 0.05), agricultural land (R
2
> 0.93, p-value < 0.02), bare land (R
2
= 0.77, p-value = 0.001), and wind stress (R
2
= 0.91, p-value = 0.04) at different times of year.
CDOM transport from the Bahamas Banks OTIS, Daniel B; CARDER, Kendall L; ENGLISH, David C ...
Coral reefs,
04/2004, Volume:
23, Issue:
1
Journal Article
Peer reviewed
The transport of colored dissolved organic matter (CDOM) between shallow banks and deep basins in the Bahamas was the focus of this study. Hydrographic and CDOM absorption measurements made on the ...Bahamas Banks and in Exuma Sound during the spring of 1999 and 2000 showed that values of salinity and CDOM absorption at 440 nm were higher on the banks (37.18 psu, 0.06 m super(-1)), compared to Exuma Sound (37.04 psu, 0.03 m super(-1)). Spatial patterns of CDOM absorption in Exuma Sound revealed that plumes of CDOM-rich water flow into Exuma Sound from the surrounding banks. These patterns were determined using Sea-viewing Wide Field-of-view Sensor (SeaWiFS) data processed using a Moderate Resolution Imaging Spectroradiometer (MODIS) algorithm to derive CDOM absorption estimates. These data, along with time-series data collected in a channel between the banks and sound, suggest that bank water rich in CDOM and salinity leaves the banks during ebb tide, whereas sound water, with lower levels of CDOM and salinity, extends onto the banks during flood tide. Because CDOM absorbs ultraviolet radiation, a causal factor of reef organism bleaching, we discuss the meaning of our findings in terms of susceptibility to coral bleaching in the Exuma region.
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