Storm impact on sea surface temperature and chlorophyll α in the Gulf of Mexico and Sargasso Sea based on daily cloud-free satellite data reconstructions

Author Posting. © American Geophysical Union, 2016. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 43 (2016): 12,199–12,207, doi:10.1002/2016GL071178.Upper ocean responses to tropical storms/hurricanes have been extensively studied using satellite observations. However, resolving concurrent sea surface temperature (SST) and chlorophyll α (chl α) responses along storm tracks remains a major challenge due to extensive cloud coverage in satellite images. Here we produce daily cloud-free SST and chl α reconstructions based on the Data INterpolating Empirical Orthogonal Function method over a 10 year period (2003–2012) for the Gulf of Mexico and Sargasso Sea regions. Daily reconstructions allow us to characterize and contrast previously obscured subweekly SST and chl α responses to storms in the two main storm-impacted regions of the Atlantic Ocean. Statistical analyses of daily SST and chl α responses revealed regional differences in the response time as well as the response sensitivity to maximum sustained wind speed and translation speed. This study demonstrates that SST and chl α responses clearly depend on regional ocean conditions and are not as universal as might have been previously suggested.Gulf of Mexico Research Initiative/GISR Grant Number: 02-S130202; NOAA Grant Number: NA11NOS0120033; NASA Grant Numbers: NNX12AP84G, NNX13AD80G2017-06-1

Tropical to extratropical : marine environmental changes associated with Superstorm Sandy prior to its landfall

Author Posting. © American Geophysical Union, 2014. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 41 (2014): 8935–8943, doi:10.1002/2014GL061357.Superstorm Sandy was a massive storm that impacted the U.S. East Coast on 22–31 October 2012, generating large waves, record storm surges, and major damage. The Coupled Ocean-Atmosphere-Wave-Sediment Transport modeling system was applied to hindcast this storm. Sensitivity experiments with increasing complexity of air-sea-wave coupling were used to depict characteristics of this immense storm as it underwent tropical to extratropical transition. Regardless of coupling complexity, model-simulated tracks were all similar to the observations, suggesting the storm track was largely determined by large-scale synoptic atmospheric circulation, rather than by local processes resolved through model coupling. Analyses of the sea surface temperature, ocean heat content, and upper atmospheric shear parameters showed that as a result of the extratropical transition and despite the storm encountering much cooler shelf water, its intensity and strength were not significantly impacted. Ocean coupling was not as important as originally thought for Sandy.Research support provided by USGS Coastal Process Project, NOAA grant NA11NOS0120033, and NASA grant NNX13AD80G is much appreciated.2015-06-1

Variational data assimilative modeling of the Gulf of Maine in spring and summer 2010

Author Posting. © American Geophysical Union, 2015. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 120 (2015): 3522–3541, doi:10.1002/2014JC010492.A data assimilative ocean circulation model is used to hindcast the Gulf of Maine [GOM) circulation in spring and summer 2010. Using the recently developed incremental strong constraint 4D Variational data assimilation algorithm, the model assimilates satellite sea surface temperature and in situ temperature and salinity profiles measured by expendable bathythermograph, Argo floats, and shipboard CTD casts. Validation against independent observations shows that the model skill is significantly improved after data assimilation. The data-assimilative model hindcast reproduces the temporal and spatial evolution of the ocean state, showing that a sea level depression southwest of the Scotian Shelf played a critical role in shaping the gulf-wide circulation. Heat budget analysis further demonstrates that both advection and surface heat flux contribute to temperature variability. The estimated time scale for coastal water to travel from the Scotian Shelf to the Jordan Basin is around 60 days, which is consistent with previous estimates based on in situ observations. Our study highlights the importance of resolving upstream and offshore forcing conditions in predicting the coastal circulation in the GOM.Research support was provided by National Oceanic and Atmospheric Administration (NOAA) grant NA06NOS4780245 for the Gulf of Maine Toxicity (GOMTOX) program. RH and DJM were also supported by NOAA grant NA11NOS4780023 under the PCMHAB program. YL was partly supported by Postdoctoral Scholar Program at the Woods Hole Oceanographic Institution, with funding provided by the George D. Grice Postdoctoral Scholarship.2015-11-1

Parental Academic Socialization: Exploring Its Association with Adolescent Learning Engagement

Learning disengagement among middle and high school students is a significant concern, with far-reaching implications for individual development. Grounded in the Development-in-Sociocultural-Context (DISC) Model, this study investigates the complex nature of school engagement as a multidimensional construct, encompassing behavioral, cognitive, and emotional engagement. It focuses on the influence of parental academic socialization on each engagement dimension, employing a multi-informant methodology. This study further examines the role of parental emotion socialization in moderating the relationships between academic socialization and student engagement. The sample included 172 adolescents and their parents, predominantly Black/African Americans (94%), with females representing 55% of the young participants. The findings highlighted that while student perceptions of academic socialization significantly predicted all three dimensions of engagement, parental reports were significant in predicting behavioral and cognitive engagement but not emotional engagement. In addition, adolescents' perceptions contributing more substantially to variations in school engagement. However, while parental emotion socialization was a notable predictor across all engagement dimensions, its moderating effect on the academic socialization-engagement relationship was not confirmed in this study. These results underscore the critical role of appropriate parental socialization in children's education to promote learning engagement and mitigate potential negative consequences

Dispersion of a tracer in the deep Gulf of Mexico

Author Posting. © American Geophysical Union, 2016. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 121 (2016): 1110–1132, doi:10.1002/2015JC011405.A 25 km streak of CF3SF5 was released on an isopycnal surface approximately 1100 m deep, and 150 m above the bottom, along the continental slope of the northern Gulf of Mexico, to study stirring and mixing of a passive tracer. The location and depth of the release were near those of the deep hydrocarbon plume resulting from the 2010 Deepwater Horizon oil well rupture. The tracer was sampled between 5 and 12 days after release, and again 4 and 12 months after release. The tracer moved along the slope at first but gradually moved into the interior of the Gulf. Diapycnal spreading of the patch during the first 4 months was much faster than it was between 4 and 12 months, indicating that mixing was greatly enhanced over the slope. The rate of lateral homogenization of the tracer was much greater than observed in similar experiments in the open ocean, again possibly enhanced near the slope. Maximum concentrations found in the surveys had fallen by factors of 104, 107, and 108, at 1 week, 4 months, and 12 months, respectively, compared with those estimated for the initial tracer streak. A regional ocean model was used to simulate the tracer field and help interpret its dispersion and temporal evolution. Model-data comparisons show that the model simulation was able to replicate statistics of the observed tracer distribution that would be important in assessing the impact of oil releases in the middepth Gulf.This research was made possible by a grant from The Gulf of Mexico Research Initiative.2016-08-0

Ocean–atmosphere dynamics during Hurricane Ida and Nor’Ida : an application of the coupled ocean–atmosphere–wave–sediment transport (COAWST) modeling system

This paper is not subject to U.S. copyright. The definitive version was published in Ocean Modelling 43-44 (2012): 112–137, doi:10.1016/j.ocemod.2011.12.008.The coupled ocean–atmosphere–wave–sediment transport (COAWST) modeling system was used to investigate atmosphere–ocean–wave interactions in November 2009 during Hurricane Ida and its subsequent evolution to Nor’Ida, which was one of the most costly storm systems of the past two decades. One interesting aspect of this event is that it included two unique atmospheric extreme conditions, a hurricane and a nor’easter storm, which developed in regions with different oceanographic characteristics. Our modeled results were compared with several data sources, including GOES satellite infrared data, JASON-1 and JASON-2 altimeter data, CODAR measurements, and wave and tidal information from the National Data Buoy Center (NDBC) and the National Tidal Database. By performing a series of numerical runs, we were able to isolate the effect of the interaction terms between the atmosphere (modeled with Weather Research and Forecasting, the WRF model), the ocean (modeled with Regional Ocean Modeling System (ROMS)), and the wave propagation and generation model (modeled with Simulating Waves Nearshore (SWAN)). Special attention was given to the role of the ocean surface roughness. Three different ocean roughness closure models were analyzed: DGHQ (which is based on wave age), TY2001 (which is based on wave steepness), and OOST (which considers both the effects of wave age and steepness). Including the ocean roughness in the atmospheric module improved the wind intensity estimation and therefore also the wind waves, surface currents, and storm surge amplitude. For example, during the passage of Hurricane Ida through the Gulf of Mexico, the wind speeds were reduced due to wave-induced ocean roughness, resulting in better agreement with the measured winds. During Nor’Ida, including the wave-induced surface roughness changed the form and dimension of the main low pressure cell, affecting the intensity and direction of the winds. The combined wave age- and wave steepness-based parameterization (OOST) provided the best results for wind and wave growth prediction. However, the best agreement between the measured (CODAR) and computed surface currents and storm surge values was obtained with the wave steepness-based roughness parameterization (TY2001), although the differences obtained with respect to DGHQ were not significant. The influence of sea surface temperature (SST) fields on the atmospheric boundary layer dynamics was examined; in particular, we evaluated how the SST affects wind wave generation, surface currents and storm surges. The integrated hydrograph and integrated wave height, parameters that are highly correlated with the storm damage potential, were found to be highly sensitive to the ocean surface roughness parameterization.Primary funding for this study was furnished by the US Geological Survey, Coastal and Marine Geology Program, under the Carolinas Coastal Processes Project

Data assimilative modeling investigation of Gulf Stream Warm Core Ring interaction with continental shelf and slope circulation

Author Posting. © American Geophysical Union, 2014. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 119 (2014): 5968–5991, doi:10.1002/2014JC009898.A data assimilative ocean circulation model is used to hindcast the interaction between a large Gulf Stream Warm Core Ring (WCR) with the Mid-Atlantic Bight (MAB) shelf and slope circulation. Using the recently developed Incremental Strong constraint 4D Variational (I4D-Var) data assimilation algorithm, the model assimilates mapped satellite sea surface height (SSH), sea surface temperature (SST), in situ temperature, and salinity profiles measured by expendable bathythermograph, Argo floats, shipboard CTD casts, and glider transects. Model validations against independent hydrographic data show 60% and 57% error reductions in temperature and salinity, respectively. The WCR significantly changed MAB continental slope and shelf circulation. The mean cross-shelf transport induced by the WCR is estimated to be 0.28 Sv offshore, balancing the mean along-shelf transport by the shelfbreak jet. Large heat/salt fluxes with peak values of 8900 W m−2/4 × 10−4 kg m−2 s−1 are found when the WCR was impinging upon the shelfbreak. Vorticity analysis reveals the nonlinear advection term, as well as the residual of joint effect of baroclinicity and bottom relief (JEBAR) and advection of potential vorticity (APV) play important roles in controlling the variability of the eddy vorticity.Research support provided through ONR grants N00014-06-1-0739, N00014-10-1-0367, and NSF grant OCE-0927470 is much appreciated. B. Powell was supported by ONR grant N00014-09-10939. K. Chen was supported by the Woods Hole Oceanographic Institution Postdoctoral Scholar Program.2015-03-1

The influence of droplet size and biodegradation on the transport of subsurface oil droplets during the Deepwater Horizon: a model sensitivity study

A better understanding of oil droplet formation, degradation, and dispersal in deep waters is needed to enhance prediction of the fate and transport of subsurface oil spills. This research evaluates the influence of initial droplet size and rates of biodegradation on the subsurface transport of oil droplets, specifically those from the Deepwater Horizon oil spill. A three-dimensional coupled model was employed with components that included analytical multiphase plume, hydrodynamic and Lagrangian models. Oil droplet biodegradation was simulated based on first order decay rates of alkanes. The initial diameter of droplets (10–300 μm) spanned a range of sizes expected from dispersant-treated oil. Results indicate that model predictions are sensitive to biodegradation processes, with depth distributions deepening by hundreds of meters, horizontal distributions decreasing by hundreds to thousands of kilometers, and mass decreasing by 92–99% when biodegradation is applied compared to simulations without biodegradation. In addition, there are two- to four-fold changes in the area of the seafloor contacted by oil droplets among scenarios with different biodegradation rates. The spatial distributions of hydrocarbons predicted by the model with biodegradation are similar to those observed in the sediment and water column, although the model predicts hydrocarbons to the northeast and east of the well where no observations were made. This study indicates that improvement in knowledge of droplet sizes and biodegradation processes is important for accurate prediction of subsurface oil spills.National Science Foundation (U.S.) (RAPID: Deepwater Horizon Grant OCE-1048630)National Science Foundation (U.S.) (RAPID: Deepwater Horizon Grant OCE-1044573)National Science Foundation (U.S.) (RAPID: Deepwater Horizon Grant CBET-1045831)Gulf of Mexico Research Initiativ

A red tide of Alexandrium fundyense in the Gulf of Maine

Author Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of Elsevier for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part II: Topical Studies in Oceanography 103 (2014): 174-184, doi:10.1016/j.dsr2.2013.05.011.In early July 2009, an unusually high concentration of the toxic dinoflagellate Alexandrium fundyense occurred in the western Gulf of Maine, causing surface waters to appear reddish brown to the human eye. The discolored water appeared to be the southern terminus of a large-scale event that caused shellfish toxicity along the entire coast of Maine to the Canadian border. Rapid-response shipboard sampling efforts together with satellite data suggest the water discoloration in the western Gulf of Maine was a highly ephemeral feature of less than two weeks in duration. Flow cytometric analysis of surface samples from the red water indicated the population was undergoing sexual reproduction. Cyst fluxes downstream of the discolored water were the highest ever measured in the Gulf of Maine, and a large deposit of new cysts was observed that fall. Although the mechanisms causing this event remain unknown, its timing coincided with an anomalous period of downwelling-favorable winds that could have played a role in aggregating upward-swimming cells. Regardless of the underlying causes, this event highlights the importance of short-term episodic phenomena on regional population dynamics of A. fundyense.The R/V Tioga sampling effort was facilitated by event response funding from the National Oceanic Atmospheric Administration (NOAA), National Ocean Service, Center for Sponsored Coastal Ocean Research, through NOAA Cooperative Agreement NA17RJ1223. Additional support for follow-up analysis and synthesis was provided by NOAA grant NA06NOS4780245 for the Gulf of Maine Toxicity (GOMTOX) program and the Woods Hole Center for Oceans and Human Health through National Science Foundation grants OCE- 0430724 and OCE-0911031 and National Institute of Environmental Health Sciences grant 1P50-ES01274201

Advancing coastal ocean modelling, analysis, and prediction for the US Integrated Ocean Observing System

Author Posting. © The Author(s), 2017. This is the author's version of the work. It is posted here by permission of Taylor & Francis for personal use, not for redistribution. The definitive version was published in Journal of Operational Oceanography 10 (2017): 115-126, doi:10.1080/1755876X.2017.1322026.This paper outlines strategies that would advance coastal ocean modeling, analysis and prediction as a complement to the observing and data management activities of the coastal components of the U.S. Integrated Ocean Observing System (IOOS®) and the Global Ocean Observing System (GOOS). The views presented are the consensus of a group of U.S. based researchers with a cross-section of coastal oceanography and ocean modeling expertise and community representation drawn from Regional and U.S. Federal partners in IOOS. Priorities for research and development are suggested that would enhance the value of IOOS observations through model-based synthesis, deliver better model-based information products, and assist the design, evaluation and operation of the observing system itself. The proposed priorities are: model coupling, data assimilation, nearshore processes, cyberinfrastructure and model skill assessment, modeling for observing system design, evaluation and operation, ensemble prediction, and fast predictors. Approaches are suggested to accomplish substantial progress in a 3-8 year timeframe. In addition, the group proposes steps to promote collaboration between research and operations groups in Regional Associations, U.S. Federal Agencies, and the international ocean research community in general that would foster coordination on scientific and technical issues, and strengthen federal-academic partnerships benefiting IOOS stakeholders and end users.2018-05-2