Showing papers by "National Ocean Service published in 2019"

Retrieval of nearshore bathymetry from Sentinel-2A and 2B satellites in South Florida coastal waters

Abstract: This study examines the relatively high-resolution MultiSpectral Instrument (MSI) onboard Sentinel-2A and 2B for generating bathymetric maps through a ratio transform model in South Florida (United States). Atmospheric correction of imagery is implemented though ACOLITE software, providing accurate performance and consistency over different Sentinel-2A/B scenes and three different study sites. Vertical calibration uses 5–10 points collected from digital charts, independent of lidar surveys, which are used for validation and error analysis. Satellite-Derived Bathymetry (SDB) has Median Absolute Error (MedAE) of 0.5 m in West Palm Beach (at depths ranging between 0 and 18 m, limit of lidar survey for validation), 0.4 m in Key West (0–5 m), and 0.22 m in Dry Tortugas (0–6 m), in conditions with low turbidity. Accurate bathymetry mapping can be accomplished with both sensors over environments with varying water transparency conditions, with the advantage of a fast, flexible, and economical solution. The 10-m MSI can capture small-scale features, such as tidal channels, straits relevant to navigation or steep slopes. While the least error is achieved by calibrating each image separately, a generic calibration produces only a moderately greater error with MedAE still ∼1m, indicating the robustness of the approach. The research highlights the great potential of the 5-day revisit, suggesting that the twin Sentinel-2 mission of the Copernicus programme may enhance SDB to leverage its use for several operational purposes, particularly in remote and inaccessible regions of the world.

Usable Science for Managing the Risks of Sea-Level Rise.

Abstract: Sea-level rise sits at the frontier of usable climate climate change research, because it involves natural and human systems with long lags, irreversible losses, and deep uncertainty. For example, many of the measures to adapt to sea-level rise involve infrastructure and land-use decisions, which can have multigenerational lifetimes and will further influence responses in both natural and human systems. Thus, sea-level science has increasingly grappled with the implications of (1) deep uncertainty in future climate system projections, particularly of human emissions and ice sheet dynamics; (2) the overlay of slow trends and high-frequency variability (e.g., tides and storms) that give rise to many of the most relevant impacts; (3) the effects of changing sea level on the physical exposure and vulnerability of ecological and socioeconomic systems; and (4) the challenges of engaging stakeholder communities with the scientific process in a way that genuinely increases the utility of the science for adaptation decision making. Much fundamental climate system research remains to be done, but many of the most critical issues sit at the intersection of natural sciences, social sciences, engineering, decision science, and political economy. Addressing these issues demands a better understanding of the coupled interactions of mean and extreme sea levels, coastal geomorphology, economics, and migration; decision-first approaches that identify and focus research upon those scientific uncertainties most relevant to concrete adaptation choices; and a political economy that allows usable science to become used science.

Shifts in the distribution and abundance of coastal marine species along the eastern Pacific Ocean during marine heatwaves from 2013 to 2018

Abstract: Ongoing global ocean warming and a recent increase in the frequency and duration of marine heatwaves have demonstrably impacted marine ecosystems. Growing evidence points to both short- and long-term biological changes, across several levels of organization. While range shifts are among the predicted responses, few studies are focused solely on documenting such changes. Here we report ecological changes in response to marine heatwaves across multiple taxa in the eastern Pacific from central California to Baja California. Sea surface temperature data from two estuaries and one coastal site were analyzed to define the number, duration, and intensity of marine heatwaves occurring in central and southern California from 2013 to 2018. Long-term monitoring programs and short-term research projects in coastal and estuarine ecosystems serendipitously collected specimens or photographs of extralimital species from central California to the Baja California Peninsula. Spatial and temporal sampling protocols and the targeted species for six unrelated programs varied greatly, from annual to monthly at both fixed and variable locations. In addition, anomalous occurrences were reported to staff at local and regional marine and estuarine protected areas and noted in local news and social media outlets. Anomalous range detections were categorized as range expansions and extensions, reappearances, abundance increases, shifts into new habitats, and range contractions. Multiple marine heatwaves occurred from 2014 to 2018, peaking in 2015. Marine heatwaves were more intense and longer in the estuaries, with a maximum duration of 109 days in 2015. We observed 29 species that had responded to the warm water anomalies of 2014–2018 along the eastern Pacific Ocean between central California and the Baja California Peninsula: 7 expansions, 2 extensions, 10 reappearances, 7 increases, 2 shifts into new habitats, and 1 apparent contraction. These shifts included algae, invertebrates and fishes. Twenty species were observed by professional biologists involved both in long-term monitoring programs and short-term studies, 6 by amateur naturalists as part of community-based science programs in the field, and 3 through a combination of all three. Increased warm waters, sustained for an unprecedented 4 of 5 years, facilitated the northward redistribution of multiple species from several taxonomic groups. Species shifting northward were from warm-temperate and subtropical ecosystems to the south. In the absence of programs designed to detect range shifts, we must rely on the serendipitous observations of biologists conducting both long-term monitoring and short-term research, and the growing wealth of information from community-based science programs made available via online databases.

High-resolution projections of extreme heat in New York City

Abstract: Department of Mechanical Engineering, The City College of New York, New York, New York Lamont-Doherty Earth Observatory, Columbia University Earth Institute, New York, New York Department of Environmental & Climate Sciences, Brookhaven National Laboratory, Upton, New York Coast Survey Development Laboratory, Office of Coast Survey, National Ocean Service, NOAA, Silver Spring, Maryland Department of Meteorology, San Jose State University, San Jose, California

An extreme sea level indicator for the contiguous United States coastline.

Abstract: We develop an aggregated extreme sea level (ESL) indicator for the contiguous United States coastline, which is comprised of separate indicators for mean sea level (MSL) and storm surge climatology (SSC). We use water level data from tide gauges to estimate interannual to multi-decadal variability of MSL and SSC and identify coastline stretches where the observed changes are coherent. Both the MSL and SSC indicators show significant fluctuations. Indicators of the individual components are combined with multi-year tidal contributions into aggregated ESL indicators. The relative contribution of the different components varies considerably in time and space. Our results highlight the important role of interannual to multi-decadal variability in different sea level components in exacerbating, or reducing, the impacts of long-term MSL rise over time scales relevant for coastal planning and management. Regularly updating the proposed indicator will allow tracking changes in ESL posing a threat to many coastal communities, including the identification of periods where the likelihood of flooding is particularly large or small.

Developing Priority Observational Requirements from Space Using Multi-Attribute Utility Theory

Abstract: Over a two-year period beginning in 2015, a panel of subject matter experts, the Space Platform Requirements Working Group (SPRWG), carried out an analysis and prioritization of different s...

Ecosystem Services of Mesophotic Coral Ecosystems and a Call for Better Accounting

Abstract: Accounting of the goods and services provided by ecosystems to human communities provides a basis for informed sustainable development, policy, and conservation decision-making. Coral reefs provide a myriad of such goods and services to coastal communities through direct provisioning (e.g., calories and natural products), environmental supporting and regulating services (e.g., nutrient or trophic cycling and stock support), and cultural products (e.g., tourism and culturally important ecosystems). Mid-depth coral communities (30–150 m), or mesophotic coral ecosystems (MCEs), are not generally addressed in ecosystem services accounting for coral reefs; however, they may share many of the services associated with shallow coral reefs, as well as provide unique ecosystem services of their own. The growing understanding that MCEs occupy large areas of previously uncharacterized insular and continental shelves suggests coral reef valuations need to account for these ecosystems. As shallower resources continue to decline due to anthropogenic pressures, it is crucial that we understand how MCEs support coastal ecosystems and human communities. Here, we explore the development of an ecosystem services framework for MCEs in the context of those provided by shallow coral reefs and present a baseline for further development as new data and information about MCEs become available. We recommend future research properly account for and valuate MCE ecosystem services, both individually and as they relate to ecosystem services for shallow-water reefs.

Assessment of Nutrient Trading Services from Bivalve Farming

Abstract: This review examines key aspects of bivalve services, with a dual emphasis on commercial production and eutrophication control, and explores how the two can be combined by means of market instruments. Our focus is on regulatory trading services, in particular on ways in which nutrient credits can be traded for improved water quality management and better food security. We provide budgets for nutrient loading in Europe, North America, and China, factoring in point and non-point loading, and assess the contribution of finfish aquaculture. We then review the role of commercially cultivated bivalves for the same geographic areas, to assess the scope of combining farmed bivalves and top-down control of symptoms of nutrient enrichment. Water quality trading has existed as a concept for the past 40 years, but it can claim few success stories; we examine some of the challenges and potential solutions, as well as practical implementations, with a focus on non-point trading, for mitigation of diffuse nutrient loading. Finally, we discuss options for different indicators, and provide examples of how an assessment can be made, including the valuation of regulatory services provided by commercially grown bivalves. We conclude that the role of bivalves in nutrient credit trading programmes should form an integral part of ecosystem-based management. From the perspective of aquaculture enhancement, which is fundamental for improved food security, this is a triple-win, providing competitiveness of agriculture, eco-intensification of aquaculture, and greater consumer safety.

Approximation of diffuse attenuation, Kd, for MODIS high-resolution bands

Abstract: A high resolution depth attenuation product (Kdhires) was developed using MODIS 500 m and 250 m spectral bands. The Kdhires was compared with Wang’s operational Kd for the Chesapeake Bay. Minimal d...

Polyamidoamine dendrimer-PEG hydrogel and its mechanical property on differentiation of mesenchymal stem cells.

Abstract: Background Biocompatible hydrogel systems with tunable mechanical properties have been reported to influence the behavior and differentiation of mesenchymal stem cells (MSCs). Objective To develop a functionalized hydrogel system with well-defined chemical structures and tunable mechanical property for regulation of stem cell differentiation. Methods An in situ-forming hydrogel system is developed by crosslinking vinyl sulfone functionalized polyamidoamine (PAMAM) dendrimer and multi-armed thiolated polyethylene glycol (PEG) through a thiol-ene Michael addition in aqueous conditions. The viability and differentiation of MSCs in hydrogels of different stiffness are conducted for 21 days under corresponding induction media. Results MSCs are viable in synthesized hydrogels after 48 hours of culture. By varying the concentrations of PAMAM dendrimer and PEG, hydrogels of different gelation time and stiffness are achieved. The MSC differentiation indicates that more osteogenic differentiation is observed in hard gel (5,663 Pa) and more adipogenic differentiation is observed in soft gel (77 Pa) in addition to the differentiation caused by each individual induction media during the process of culture. Conclusions A biocompatible in situ-forming hydrogel system is successfully synthesized. This hydrogel system has shown influences on differentiation of MSCs and may potentially be important in developing therapeutic strategies in medical applications.

Acute and short-term administrations of delta-9-tetrahydrocannabinol modulate major gut metabolomic regulatory pathways in C57BL/6 mice.

Abstract: Delta-9-tetrahydrocannabinol (THC) is the primary psychoactive compound in Cannabis, which is studied extensively for its medicinal value. A central gap in the science is the underlying mechanisms surrounding THC's therapeutic effects and the role of gut metabolite profiles. Using a mass-spectrometry based metabolomics, we show here that intraperitoneal injection of THC in C57BL/6 mice modulates metabolic profiles that have previously been identified as integral to health. Specifically, we investigated the effects of acute (single THC injection denoted here as '1X') and short -term (five THC injections on alternate days denoted as '5X') THC administration on fecal and intestinal tissue metabolite profiles. Results are consistent with the hypothesis that THC administration alters host metabolism by targeting two prominent lipid metabolism pathways: glycerophospholipid metabolism and fatty acid biosynthesis.

Mapping the Host-Pathogen Space to Link Longitudinal and Cross-sectional Biomarker Data: Leptospira Infection in California Sea Lions (Zalophus californianus) as a Case Study

Abstract: Confronted with the challenge of understanding population-level processes, disease ecologists and epidemiologists often simplify quantitative data into distinct physiological states (e.g. susceptible, exposed, infected, recovered). However, data defining these states often fall along a spectrum rather than into clear categories. Hence, the host-pathogen relationship is more accurately defined using quantitative data, often integrating multiple diagnostic measures, just as clinicians do to assess their patients. We use quantitative data on a bacterial infection (Leptospira interrogans) in California sea lions (Zalophus californianus) to improve both our individual-level and population-level understanding of this host-pathogen system. We create a “host-pathogen space” by mapping multiple biomarkers of infection (e.g. serum antibodies, pathogen DNA) and disease state (e.g. serum chemistry values) from 13 longitudinally sampled, severely ill individuals to visualize and characterize changes in these values through time. We describe a clear, unidirectional trajectory of disease and recovery within this host-pathogen space. Remarkably, this trajectory also captures the broad patterns in larger cross-sectional datasets of 1456 wild sea lions in all states of health. This mapping framework enables us to determine an individual’s location in their time-course since initial infection, and to visualize the full range of clinical states and antibody responses induced by pathogen exposure, including severe acute disease, chronic subclinical infection, and recovery. We identify predictive relationships between biomarkers and outcomes such as survival and pathogen shedding, and in certain cases we can impute values for missing data, thus increasing the size of the useable dataset. Mapping the host-pathogen space and using quantitative biomarker data provides more nuanced approaches for understanding and modeling disease dynamics in a system, yielding benefits for the clinician who needs to triage patients and prevent transmission, and for the disease ecologist or epidemiologist wishing to develop appropriate risk management strategies and assess health impacts on a population scale. Author Summary A pathogen can cause a range of disease severity across different host individuals, and these presentations change over the time-course from infection to recovery. These facts complicate the work of epidemiologists and disease ecologists seeking to understand the factors governing disease spread, often working with cross-sectional data. Recognizing these facts also highlights the shortcomings of classical approaches to modeling infectious disease, which typically rely on discrete and well-defined disease states. Here we show that by analyzing multiple biomarkers of health and infection simultaneously, treating these values as quantitative rather than binary indicators, and including a modest amount of longitudinal sampling of hosts, we can create a map of the host-pathogen interaction that shows the full spectrum of disease presentations and opens doors for new insights and predictions. By accounting for individual variation and capturing changes through time since infection, this mapping framework enables more robust interpretation of cross-sectional data; e.g., to detect predictive relationships between biomarkers and key outcomes such as survival, or to assess whether observed disease is associated with the pathogen of interest. This approach can help epidemiologists, ecologists and clinicians to better study and manage the many infectious diseases that exhibit complex relationships with their hosts.