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Based on the comparison of zircon ages with source terranes, they inferred that the likely source for Cenozoic zircon grains was the Eastern Alkaline Province of Mexico, which comprises various volcanic fields of Cenozoic age. Armstrong-Altrin et al. (2021) reported the detrital zircon grain surface features, chemistry, and U-Pb ages in the Chachalacas beach sediments, Gulf of Mexico. Armstrong-Altrin et al. (2020) discussed the U-Pb ages of detrital zircon grains, which we reported from the Chachalacas beach in the western Gulf of Mexico. [Extracted from the article]

The U.S. states along the northern shores of the Gulf of Mexico have often been described as America's Energy Colony. This region is festooned with polluting industries, storage and waste disposal sites for toxic products, and a history of generally lax approaches to environmental public health and enforcement of regulations. This issue of New Solutions includes three interviews of groups and individuals who work for Environmental Justice in the Gulf Coast region. The interviewees provide key insights into the diverse cultural texture and social fabric of the Gulf. Their range of gulf locales and population groups embody different styles of engagement and different relationships to organizing, disseminating health and environmental risk information, and advocating for social and environmental justice. Similarities among their communities in terms of health and economic disparities, climate risks, and vulnerabilities lend credence to the idea of the Gulf as a regional Environmental Justice community.

The U.S. states along the northern shores of the Gulf of Mexico have often been described as America's Energy Colony. This region is festooned with polluting industries, storage and waste disposal sites for toxic products, and a history of generally lax approaches to environmental public health and enforcement of regulations. This issue of New Solutions includes three interviews of groups and individuals who work for environmental justice in the Gulf Coast region. The interviewees provide key insights into the diverse cultural texture and social fabric of the Gulf. Their range of gulf locales and population groups embody different styles of engagement and different relationships to organizing, disseminating health and environmental risk information, and advocating for social and environmental justice. Three additional interviews will appear in the next issue of New Solutions.

We utilize a coupled economy–agroecology–hydrology modeling framework to capture the cascading impacts of climate change mitigation policy on agriculture and the resulting water quality cobenefits. We analyze a policy that assigns a range of United States government’s social cost of carbon estimates ($51, $76, and $152/ton of CO2-equivalents) to fossil fuel–based CO2 emissions. This policy raises energy costs and, importantly for agriculture, boosts the price of nitrogen fertilizer production. At the highest carbon price, US carbon emissions are reduced by about 50%, and nitrogen fertilizer prices rise by about 90%, leading to an approximate 15% reduction in fertilizer applications for corn production across the Mississippi River Basin. Corn and soybean production declines by about 7%, increasing crop prices by 6%, while nitrate leaching declines by about 10%. Simulated nitrate export to the Gulf of Mexico decreases by 8%, ultimately shrinking the average midsummer area of the Gulf of Mexico hypoxic area by 3% and hypoxic volume by 4%. We also consider the additional benefits of restored wetlands to mitigate nitrogen loading to reduce hypoxia in the Gulf of Mexico and find a targeted wetland restoration scenario approximately doubles the effect of a low to moderate social cost of carbon. Wetland restoration alone exhibited spillover effects that increased nitrate leaching in other parts of the basin which were mitigated with the inclusion of the carbon policy. We conclude that a national climate policy aimed at reducing greenhouse gas emissions in the United States would have important water quality cobenefits. [ABSTRACT FROM AUTHOR]

A content analysis challenges the notion that elite newspapers can speak for local dailies. Gulf dailies focused on the environment until the well was capped and then shifted to the local economy, while the national dailies focused on the accident. [ABSTRACT FROM AUTHOR]

The cornerstone assumption of all Flood Geology models is that rocks can form quickly (i.e., within the timeframe of months to years). However, to date, only isolated examples from the field have been used to support the hypothesis without any quantitative justification. This paper therefore presents the theoretical basis (originally set out by Terzaghi, 1922) for determining the timescales for the first phase of lithification, the mechanical compaction of the sediment under its self-weight (otherwise known as consolidation). The paper demonstrates that when basic soil mechanics theory is applied to the consolidation of thick clay layers of the order of 1,000 m such as those found in the North Sea, Gulf of Mexico, and the Caspian Sea, the timescales predicted for compaction are orders of magnitude greater than is currently assumed. Additionally, it is shown that there is a physical limit to the rate at which sediment can accumulate without creating excessive pore pressure and inducing geotechnical failures. For clay, this limit is approximately 0.1 m/yr, and, for silt, approximately 10 m/yr. [ABSTRACT FROM AUTHOR]

Strontium and barium to calcium ratios are often used as proxies for tracking animal movement across salinity gradients. As sea level rise continues, many estuarine rivers in the world face saltwater intrusion, which may cause changes in mobility and distribution of these metals upstream. Despite intensive research on metal adsorption and desorption in marine systems, knowledge of the spatiotemporal distribution of these elements along estuarine rivers is still limited. In this study, we conducted an intensive monitoring of Sr and Ba dynamics along an 88 km long estuary, the Calcasieu River in South Louisiana, USA, which has been strongly affected by saltwater intrusion. Over the period from May 2013 to August 2015, we collected monthly water samples and performed in-situ water quality measurements at six sites from the upstream to the river mouth, with a salinity range from 0.02 to 29.50 ppt. Water samples were analyzed for Sr, Ba, and Ca concentrations. In-situ measurements were made on salinity, pH, water temperature, dissolved oxygen concentration, and specific conductance. We found that the Sr and Ca concentrations and the Sr =Ca ratio all increased significantly with increasing salinity. The average Sr concentration at the site closest to the Gulf of Mexico (site 6) was 46.21 μmol L-1, which was about 130 times higher than that of the site furthest upstream (site 1, 0.35 ìmol L-1). The average Ca concentration at site 6 was 8.19 mmol L-1, which was about 60 times higher than that of site 1 (0.13 mmol L-1). The average Sr =Ca ratio at site 6 (8.41mmolmol-1) was about 3 times the average Sr = Ca ratio at site 1 (2.89 mmol mol-1). However, the spatial variation in Ba concentration was marginal, varying from 0.36 μmol L-1 at site 6 to 0.47 at site 5. The average Ba = Ca ratio at site 1 (4.82 mmol mol-1) was about 54 times the average Ba = Ca ratio at site 6 (0.09 mmol mol-1), showing a clear negative relation between the Ba = Ca ratio and increasing salinity. All the elemental concentrations and ratios had considerable seasonal variations, with significant differences among sampling months for the Sr, Ba concentrations and the Ba = Ca ratio (p < 0.01). The results from this study suggest that concentrations of Sr and Ca in the world's estuaries will very likely increase in the future as sea level rise continues. For low-gradient estuarine rivers such as the Calcasieu River in South Louisiana, USA, water chemistry upstream would experience substantial Sr and Ca enrichment, which could affect aquatic environments and biological communities. [ABSTRACT FROM AUTHOR]

We present evidence of temporal variation in nitrous oxide (N2O) concentrations in the bottom waters of the northern Gulf of Mexico (nGOM) hypoxic zone. The analysis is based on a conceptual model simulating N2O biogeochemical processes in conjunction with water-column O2 levels, derived from summer Texas-Louisiana shelf-wide hydrographic data for twenty Julys between 1985 and 2007. The mean modeled nGOM N2O concentration was 7.7±6.7 nmol L-1, and was significantly correlated with the areal extent of hypoxia. Our modeling analysis indicates that the nGOM is a persistent summer source of N2O, and nitrification is a primary factor leading to its production in this region. Based on the ongoing increase in the areal extent of hypoxia in the nGOM, we conclude that N2O emission from this environmentally stressed region will continue to increase into the future contributing to the global increase in greenhouse gases. [ABSTRACT FROM AUTHOR]

This paper shows the observation and estimation of convective wind gusts by different satellite sensors at the C-band (Sentinel-1 SAR) and L-band (ALOS-1 SAR and SMAP radiometer) over Lake Victoria, the Gulf of Guinea, and the Gulf of Mexico. These areas are significantly impacted by deep convection associated with strong surface winds and heavy rainfall. In particular, the collocation of Sentinel-1 and SMAP images enables the observation of the movement of surface wind gusts corresponding to that of deep convective clouds. The convective wind intensity estimated from Sentinel-1 and SMAP data varies from 10 to 25 m/s. Additionally, we present an agreement in the observation of deep convective clouds, dynamics, and strong surface winds by different satellite sensors, including Meteosat geostationary (GEO), Aeolus Lidar, and Sentinel-1 SAR, respectively. We also evaluate the estimated convective wind gusts by comparison with the in situ measurements of the weather stations installed in the Gulf of Mexico, where deep convection occurs regularly. The result shows an agreement between the two wind sources estimated and measured. Likewise, the peaks of the measured wind gusts correspond to the occurrence of deep convective clouds observed by the GOES-16 GEO satellite. [ABSTRACT FROM AUTHOR]

The anticyclonic Loop Current Eddy (LCE) shedding events are strongly associated with the evolution of Loop Current Frontal Eddies (LCFEs) over the eastern Gulf of Mexico (GoM). A numerical simulation, in tandem with in situ measurements and satellite data, was used to investigate the Loop Current (LC) evolution and the surrounding LCFEs formation, structure, growth and migration during the Eddy Ekman and Eddy Franklin shedding events in the summers of 2009 and 2010, respectively. During both events, Northern GoM LCFEs appeared vertically coherent to at least 1500m in temperature observations. They propagated towards the base of the LC where, together with the migration of Campeche Bank eddies from south of the LC, contributed to its "necking down". Growth of Campeche Bank LCFEs involved in Eddy Franklin was partially attributed to Campeche Bank waters following upwelling events. Slope processes associated with such upwelling include offshore exports of high positive vorticity that may trigger cyclone formation and growth. The advection and growth of LCFEs, originating from the northern and southern GoM, and their interaction with the LC over the LCE detachment area favor shedding conditions and may lead to the final separation of the LCE. [ABSTRACT FROM AUTHOR]

This paper examined characteristics and travel behaviour of vessel traffic at the entrance of the Houston Ship Channel (HSC) using automatic identification system (AIS) data collected for the whole year of 2014. The paper aimed to investigate the travel behaviour of vessels in a busy inland waterway. For any further analysis such as vessel traffic delay analysis, schedule optimization, risk analysis, etc., it is important to first know the traffic characteristics and travel behaviour of vessels in the channel. The entrance of the HSC sees the following types of vessels: cargos, tankers, passenger ships, harbour tugs, towing vessels, etc. Among them, cargos and tankers dominate the flow at this section of the HSC. Travel behaviour of cargos and tankers, especially those vessels carrying dangerous goods, was analyzed at this section of the HSC, which was divided into two zones with the same length. Based on vessels’ travel directions, trips were categorized into outbound (towards the Gulf of Mexico) and inbound (away from the Gulf). The annual average hourly traffic was calculated for all vessels combined, as well as for major vessel types, for both directions at each zone. Specifically, the traffic speeds of different vessel types were studied. In general, the speed at the entrance of the HSC is low, and the traffic speeds of each type of vessel (tankers, cargos, as well as tankers and cargos carrying dangerous goods) were normally distributed. Moreover, the relationship between traffic speeds and density was analyzed, and found that the traffic speeds were basically independent from the density of vessels in the waterway. This paper was a preliminary study of vessel traffic characteristics and travel behaviour analysis. The methodology involved in this paper can be applied to other inland waterways to investigate travel behaviour of vessel traffic. The results of the paper revealed some important facts about characteristics and travel behaviour of vessel traffic at the entrance of the channel, which will help better understand of vessel traffic pattern and can be used for further studies on waterway transportation. [ABSTRACT FROM AUTHOR]

With an extension of > 40 km2 the recently discovered Campeche cold-water coral province located at the northeastern rim of the Campeche Bank in the southern Gulf of Mexico belongs to the largest coherent cold-water coral areas discovered so far. The Campeche province consists of numerous 20 to 40m high coral ridges that are developed in intermediate water depths of 500 to 600 m. The ridges are colonized by a vivid cold-water coral ecosystem that covers the upper flanks and summits. The rich coral community is dominated by the framework-building scleractinia Enallopsammia profunda and Lophelia pertusa while the associated benthic megafauna shows a rather scarce occurrence. The recent environmental setting is characterized by a high surface water production caused by a local upwelling center and a dynamic bottom water regime comprising vigorous bottom currents, internal waves and strong density contrasts, which all together provide optimal conditions for the growth of cold-water corals. The strong hydrodynamics -- potentially supported by the diel vertical migration of zooplankton in the Campeche area -- drive the delivering of food particles to the corals. The Campeche cold-water coral province is, thus, an excellent example highlighting the importance of the hydrographic setting in securing the food supply for the development of large and vivid cold-water coral ecosystems. [ABSTRACT FROM AUTHOR]

The article outlines the research of Jake Bailey in disproving the pre-historic microfossils discovered in 1998 in South China as fossils of Algae. Two researchers influenced his work. Samantha Joye presented evidence of reductive cell division in giant sulfur bacteria from the Gulf of Mexico. Heide Schulz researched in biochemical activities in giant sulfur bacteria in the formation of phosphorite. In his paper, Jake Bailey declares the microfossils as fossilized giant sulfur bacteria.

In 2022, Houston, TX became a nexus for field campaigns aiming to further our understanding of the feedbacks between convective clouds, aerosols and atmospheric boundary layer (ABL) properties. Houston's proximity to the Gulf of Mexico and Galveston Bay motivated the collection of spatially distributed observations to disentangle coastal and urban processes. This paper presents a value-added ABL dataset derived from observations collected by eight research teams over 46 days between 2 June - 18 September 2022. The dataset spans 14 sites distributed within a ~80-km radius around Houston. Measurements from three types of instruments are analyzed to objectively provide estimates of nine ABL parameters, both thermodynamic (potential temperature, and relative humidity profiles and thermodynamic ABL depth) and dynamic (horizontal wind speed and direction, mean vertical velocity, updraft and downdraft speed profiles, and dynamical ABL depth). Contextual information about cloud occurrence is also provided. The dataset is prepared on a uniform time-height grid of 1 h and 30 m resolution to facilitate its use as a benchmark for forthcoming numerical simulations and the fundamental study of atmospheric processes. [ABSTRACT FROM AUTHOR]

This paper for the first time, to the best of our knowledge, reports 10 case histories of jack-up rig installation in different locations of the Gulf of Mexico consisting of seabed soil stratigraphy with weak surface (soft) clay over strong (stiff) clay or sand underlying layers. For each case, site investigation data are analyzed, leading to the selection of design undrained shear strength profile for the clay layers and relative density for the sand layers. A statistical averaging method recommended in the InSafeJIP guidelines (adopted in ISO 19905-1) is used to obtain the best fit of the undrained shear strength profile in the clay layers. The spudcan shape and dimensions and load-penetration profiles are presented. Measured load-penetration profiles are compared with the calculated profiles using the squeezing methods presented in ISO 19905-1, Clarom, and recently published papers. Large deformation finite element analyses were conducted for some sites to provide supporting insight into the penetration resistance profiles and potentially mobilized squeezing mechanisms. The lessons learned are noted, which will provide valuable insights for practitioners for estimating the behavior of jack-up installations in seabed soil consisting of surface weak-over-underlying strong soil stratigraphy. [ABSTRACT FROM AUTHOR]

The USA recently announced it is planning on deploying 30 GW of offshore wind by 2030 (national goal for offshore wind). Part of this development will be in the Gulf of Mexico, which has both wind potential and pre-existing oil and gas pipelines, only a portion of which is currently being used. Examining whether these assets can be used to economically transport power back from future Gulf wind farms should be a first step for developers. The question of whether laying new high-voltage direct current submarine cable versus repurposing pipeline to transport wind power will be examined. This paper looks at the hydrogen market and its use to transport wind power, what it would take to retrofit pipeline to carry hydrogen, a cost analysis given available data, and a look at potential policy support. There is a need to assess pipelines individually; however, retrofitting existing infrastructure should be considered an alternative to laying new submarine transmission cables. Additionally, alleviating the issue of oil and gas stranded assets through pipeline reuse may provide political support in hastening the energy transition. [ABSTRACT FROM AUTHOR]

Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria which ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, East America, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous more easily accessible shallow marine species were studied. We here provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to Marmara Sea, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 51 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae), and compared among families with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions, yet relatively little is known regarding their diversity and functioning apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on Oceans, we advocate for a better assessment of bivalve symbioses diversity in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change [ABSTRACT FROM AUTHOR]

The storage potential of hydrocarbon reservoirs in the central Gulf of Mexico (GOM) makes future development of CO2 storage projects in those areas promising for secure, large-scale, and long-term storage purposes. Focusing on the producing and depleted hydrocarbon fields in the continental slope of the central GOM, this paper analyzed, assessed, and screened the producing sands and evaluated their CO2 storage potential. A live interactive CO2 storage site screening system was built in the SAS® Viya system with a broad range of screening criteria combined from published studies. This offers the users a real-time assessment of the storage sites and enables them to adjust the filters and visualize the results to determine the most suitable filter range. The CO2 storage resources of the sands were estimated using a volumetric equation and the correlation developed by the National Energy Technology Laboratory (NETL). The results of this study indicate that 1.05 gigatons of CO2 storage resources are available in the developed reservoirs at the upper slope area of the central GOM. The Mississippi Canyon and Green Canyon protraction areas contain the fields with the largest storage resources. [ABSTRACT FROM AUTHOR]

Vessel electronic monitoring (EM) systems used in fisheries around the world apply a variety of cameras to record catch as it is brought on deck and during fish processing activities. In EM work conducted by the Center for Fisheries Electronic Monitoring at Mote (CFEMM) in the Gulf of Mexico commercial reef fish fishery, there was a need to improve upon current technologies to enhance camera views for accurate species identification of large sharks, particularly those that were released while underwater at the vessel side or underneath the hull. This paper describes how this problem was addressed with the development of the first known EM system integrated underwater camera (UCAM) with a specialized vessel-specific deployment device on a bottom longline reef fish vessel. Data are presented based on blind video reviews from CFEMM trained reviewers of the resulting UCAM video footage compared with video from only the overhead EM cameras from 68 gear retrievals collected from eight fishing trips. Results revealed that the UCAM was a successful tool for capturing clear underwater video footage of released large (>2m) sharks to enable reviewers to improve individual species identification, determination, and fate by 34.4%. This was particularly important for obtaining data on incidental catches of large protected shark species. It also provided clear underwater imagery of the presence of potential predators such as marine mammals close to the vessel, more specifically bottlenose dolphin (Tursiops truncatus) during gear retrieval, which often damaged or removed catch. This information is intended to assist researchers in need of gathering critical data on bycatch in close proximity to a vessel in which conventional overhead EM cameras are limited. [ABSTRACT FROM AUTHOR]

Since 2016, the Bureau of Safety and Environmental Enforcement (BSEE) has collected decommissioning expenditure data from operators in the deepwater US Gulf of Mexico, defined as water depth greater than 122 m, to estimate the decommissioning liability of leases. BSEE uses both statistical tools and work decomposition methods to estimate the decommissioning cost of all active wells, structures, and pipelines on deepwater leases. The purpose of this paper is to evaluate BSEE cost estimates in the deepwater US Gulf of Mexico across four decommissioning stages and to infer unit cost statistics and cost functions in the region. Fixed platforms in 250–500 m water depth are expected to cost between $10 and $80 million to decommission, spars about $55 million, ship-shape floaters around $30 million, and tension leg platforms and their smaller (mini) versions between $18 and $25 million. The deepwater decommissioning market value is estimated at $24.3 billion circa 2022. [ABSTRACT FROM AUTHOR]

Natural methane hydrate has often been observed in sand layers that contain no particulate organic carbon (POC), but are surrounded by organic-rich, fine-grained marine muds. In this paper, we develop a reactive transport model (RTM) of a microbially-mediated set of POC degradation reactions, including hydrolysis of POC driven by extracellular enzymes, fermentation of the resulting high-molecular weight dissolved organic carbon (HMW-DOC), and methanogenesis that consumes low-molecular weight dissolved organic carbon (LMW-DOC). These processes are mediated by two groups of microbes, fermenters and methanogens that are heterogeneously distributed in different lithologies, with the largest numbers of microbes in the large pores of coarse-grained layers. We find that the RTM can reproduce methane hydrate occurrences observed in two different geological environments, at Walker Ridge Site 313-H (Gulf of Mexico) and IODP Site U1325 (Cascadia Margin). We also find that microbes can degrade POC even if they are physically separated, as extracellular enzymes and DOC can diffuse away from where they are produced by microbes. Microbial activity is highest at relatively early times after burial at shallow depths and near lithological boundaries, where concentration gradients transport solutes to intervals that contain the most microbes. [ABSTRACT FROM AUTHOR]

Simple Summary: This study reports the results of a multidisciplinary research on Mediterranean pelagic octopods belonging to the species Argonauta argo, Ocythoe tuberculata, Tremoctopus gracilis and Tremoctopus violaceus for the first time. The study area was the Strait of Messina and southern Tyrrhenian Sea. We used information from stranding events, accidental fishing catches and stomach contents of large predators (albacore, bluefin tuna, swordfish and Mediterranean spearfish). We analysed 47 fresh octopods, including exceptional records of rare males, and 330 individuals found in the stomachs of 800 predators. The analysis of genetic aspects was used to provide further details on the life and identity of these species. The present paper represents the first all-encompassing study on all Mediterranean holopelagic octopods belonging to Argonautoidea (Argonauta argo, Ocythoe tuberculata, Tremoctopus gracilis, Tremoctopus violaceus). Argonautoidea octopuses were collected by different sampling methods in the Strait of Messina and southern Tyrrhenian Sea. The aim of this paper was to improve knowledge, using information from different data sources, such as the study of stranded individuals or accidental caught specimens, as well as the analysis of stomach content of large pelagic fishes. Moreover, we investigated their taxonomic profile through the amplification of the mitochondrial cytochrome c oxidase subunit I (COI). Overall, 47 fresh holopelagic octopods were collected, including valuable records of rare males. Moreover, 330 Argonautoidea octopuses were found in the stomachs of 800 predators. The results provided evidence that these cephalopods are more abundant than thought in the past. The molecular approach supported the ecological results with interesting insights. The similarity-based identifications and tree-based methods indicated that three females could be identified as Tremoctopus violaceus in agreement with their morphological classifications. The sequences obtained from the two T. gracilis individuals were clustered with the sequences of Tremoctopus violaceus from the Gulf of Mexico and were differentiated from the sequences attributed to T. gracilis and T. robsoni. The study represents a valuable contribution to the genetic characterization of Mediterranean individuals of the genera Tremoctopus, Argonauta and Ocythoe. [ABSTRACT FROM AUTHOR]

For an offshore facility, identifying safety critical equipment (SCE) and ensuring that they are designed, built, installed, and commissioned based on certain design performance criteria is key to ensuring a safe design. In some parts of the world, such as in the North Sea, regulatory requirements dictate a mandatory third‐party verification of the SCE and their corresponding design performance criteria. In other parts of the world, such as in the Gulf of Mexico, however, there is no such regulatory requirement; it is, therefore, up to the operator to provide assurance that the SCE is designed, built and installed per the design criteria. This paper describes a methodology for ensuring the integrity of SCE implementation and applies the learnings from the BP Mad Dog 2 Project (Argos platform). This methodology provides assurance of the integrity of the SCE during the engineering and construction phases of a project, along with some valuable lessons learned from managing the assurance of the SCE on the project via multiple contractors. This paper discusses the identification of the SCE and provides a brief summary of the development of the relevant design performance criteria for each category of SCE. The paper focuses on a two‐step process to track each design criterion via conducting engineering assurance and then providing field verification, where the design criteria are tested either at the manufacturing site, construction site or through commissioning activities. Some valuable lessons learned from the Mad Dog 2 Project are shared, along with some of the potential pitfalls in managing the assurance process of the SCE design criteria, especially in a complex project organization where multiple contractors are involved. [ABSTRACT FROM AUTHOR]

In this paper, the importance of model horizontal resolution in mixing and dispersion is investigated by comparing two data‐assimilative high‐resolution simulations (4 and 1 km), one of which is submesoscale‐permitting. By employing both Eulerian and Lagrangian metrics, upper‐ocean differences between the mesoscale‐resolving and submesoscale‐permitting simulations are examined in the northeastern Gulf of Mexico, a region of high mesoscale and submesoscale activity. Mixing in both simulations is explored by conducting Lagrangian experiments to track the generation of Lagrangian coherent structures (LCSs) and their associated transport barriers. Finite‐time Lyapunov exponent (FTLE) fields show higher separation rates of fluid particles in the submesoscale‐permitting case, which indicate more vigorous mixing with differences being more pronounced in the shelf regions (depths ≤ 500 m). The extent of the mixing homogeneity is examined using probability density functions (PDFs) of FTLEs with results suggesting that mixing is heterogeneous in both simulations, but some homogeneity is exhibited in the submesoscale‐permitting case. The FTLE fields also indicate that chaotic advection dominates turbulent mixing in both simulations regardless of the horizontal resolution. In the submesoscale‐permitting experiment, however, smaller scale LCSs emerge as noise‐like filaments that suggest a larger turbulent mixing component than in the mesoscale‐resolving experiment. The impact of resolution is then explored by investigating the spread of oil particles at the location of the Deepwater Horizon oil spill. Plain Language Summary: Small‐scale processes (0.1–50 km) play a critical role in upper‐ocean water transport and mixing. Thus, the added value from resolving these finer scales in numerical models is evaluated by comparing two high‐resolution numerical simulations in the northeastern Gulf of Mexico: one at 1 km horizontal resolution that truly resolves features on the order of 10 km and one at 4 km that only resolves features greater than 50 km. Passive fluid particle experiments are conducted to document the mixing and identify structures that act as barriers to transport between fluids with different properties and determine the fate of dispersants in the ocean. In both simulations, the particles' distribution is spatially heterogeneous, which indicates that mixing is largely controlled by these structures. Results also show that neighboring fluid particles separate faster from one another in the 1 km simulation than in the 4 km simulation, meaning that mixing of fluids is more intense. Lastly, we find that the 1 km simulation is more realistic when applied to oil particle dispersion at the location of the Deepwater Horizon oil spill. Key Points: Resolving submesoscale motions leads to increased Lagrangian transport and mixing as well as the generation of more intricate LCSsChaotic advection dominates turbulent mixing regardless of the horizontal model resolution (either 4 km or 1 km)Submesoscale‐permitting simulation yields reduced error against drifter observations compared to mesoscale‐resolving counterpart [ABSTRACT FROM AUTHOR]

The Texas-Louisiana shelf in the Northern Gulf of Mexico receives large inputs of nutrients and freshwater from the Mississippi/Atchafalaya River system. The nutrients stimulate high rates of primary production in the river plume, which contributes to the development of a large and recurring hypoxic area in summer. The mechanistic links between hypoxia and river discharge of freshwater and nutrients are complex as the accumulation and vertical export of organic matter, the establishment and maintenance of vertical stratification, and the microbial degradation of organic matter are controlled by a non-linear interplay of factors. We present results from a realistic, 3-dimensional, physical-biological model that includes the processes thought to be of first order importance to hypoxia formation and demonstrate that the model realistically reproduces many features of observed nitrate and phytoplankton dynamics including observed property distributions and rates. We then contrast the environmental factors and phytoplankton source and sink terms characteristic of three model subregions that represent an ecological gradient from eutrophic to oligotrophic conditions. We analyze specifically the reasons behind the counterintuitive observation that primary production in the light-limited plume region near the Mississippi River delta is positively correlated with river nutrient input. We find that, while primary production and phytoplankton biomass are positively correlated with nutrient load, phytoplankton growth rate is not. This suggests that accumulation of biomass in this region is not primarily controlled bottom up by nutrient-stimulation, but top down by systematic differences in the loss processes. We hypothesize that increased retention of river water in high discharge years explains this phenomenon. [ABSTRACT FROM AUTHOR]

The dryline, often associated with the development of severe storms in the Southern Great Plains of the United States of America, is a boundary layer phenomenon that occurs when a warm and moist air mass from the Gulf of Mexico meets a hot and dry air mass from the southwest desert area. An accurate knowledge of the water vapor spatio-temporal variability in the lower part of the atmosphere is crucial for a better understanding of the evolution of the dryline. The tropospheric refractivity, directly related to water vapor content, is a proxy for the water vapor content of the troposphere. It has already been demonstrated that the refractivity and the refractivity vertical gradient can be jointly estimated from radar phase measurements. In fact, it has been shown that using kriging interpolation techniques, accurate refractivity maps within the coverage area of the radar can be obtained with high temporal resolution. In this paper, a detailed analysis of the time series of radar-based refractivity maps obtained during a dryline that occurred on the afternoon of 22 May 2002 during the International H 2 O Project ( I H O P _ 2002 ) is presented. Comparisons between the time series of radar refractivity maps, obtained with the NCAR S-Pol radar, and the refractivity measurements derived from automatic ground-based weather stations and the AERI instrument, placed at different locations within the coverage area of the NCAR S-Pol radar, demonstrate the accuracy of radar refractivity estimates even for highly variable conditions, both in time and space, in the troposphere. Correlation coefficients higher than 0.95 are obtained in all weather station locations. Regarding the RMSE, errors less than 6 N-units are obtained for all cases, being even as low as 2.92 N-units at some locations. [ABSTRACT FROM AUTHOR]

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Previous studies have demonstrated that the influence of the El Niño–Southern Oscillation (ENSO) on the Euro-Atlantic atmospheric circulation varies considerably during the boreal winter. Compared to the late winter (January–March) relationship, the early winter (November–December) teleconnection is more uncertain and less understood. In this paper, we revisited this early winter regional ENSO teleconnection using the Hadley Centre Global Sea Ice and Sea Surface Temperature (HadISST) and the European Centre for Medium-Range Weather Forecasting (ECMWF) fifth generation reanalysis (ERA5) datasets for the period 1979–2022. It was found that the signal projected well onto the second dominant mode of Euro-Atlantic atmospheric variability, the East Atlantic Pattern (EAP), rather than the previously mentioned North Atlantic Oscillation (NAO). This influence is associated with ENSO-induced dipolar convection anomalies in the Gulf of Mexico and Caribbean Sea (GMCA), which leads to an EAP via exciting Rossby waves propagating northward into the North Atlantic. We further revealed that this ENSO–EAP teleconnection underwent a pronounced interdecadal strengthening around the late 1990s. Prior to the late 1990s, the convective response to ENSO in the GMCA was weak. The atmospheric responses over the Euro-Atlantic were mainly driven by the ENSO-induced convective forcing in the tropical Indian Ocean, which favors an NAO-like pattern. In contrast, since the late 1990s, ENSO has induced stronger precipitation anomalies in the GMCA, which exert a dominant influence on the Euro-Atlantic atmospheric circulation and produce an EAP. These results have useful implications for the further understanding of ENSO-related early winter atmospheric and climate variability in the Euro-Atlantic region. [ABSTRACT FROM AUTHOR]

This paper discusses the flotation of cables and pipelines that have been trenched using jet trenching during reconsolidation of the seabed soil. Utilising previously published data on the variation of clay strength with liquidity index, it is demonstrated for the first time that, while current industry guidance is appropriate for the low-plasticity clays for which much previous research has been carried out, it may be overly conservative for high-plasticity clays such as those found in the Gulf of Guinea or the Gulf of Mexico, owing to the differing strength and density characteristics of these soils. [ABSTRACT FROM AUTHOR]

This paper examines precipitation associated with large-scale patterns of water vapor transport in the eastern United States. Daily 4 km gridded precipitation from PRISM (1981–2017) is sorted into a subset according to previously defined patterns of water vapor transport supplying the moisture on each day. These subsets are then analyzed to characterize the precipitation associated with each water vapor transport pattern. While each moisture transport pattern is associated with at least occasional precipitation, with seasonal variations, the highest precipitation averages are issued from near-coastal and coastal moisture transport patterns. Moisture transport patterns emanating from the Gulf of Mexico are associated with highest average precipitation inland. Each pattern has a spatially distinct contribution to annual and seasonal precipitation totals. The water vapor transport patterns of moderate intensity and moderate associated precipitation contribute the most to average annual precipitation. Most moisture transport patterns are associated with statistically significant increases in areas of very heavy precipitation (x ≥ 50 mm). By identifying which atmospheric moisture transport patterns are responsible for increasing areas of very heavy precipitation, and by characterizing the precipitation totals and contribution associated with each, this paper demonstrates the utility of examining precipitation variability through moisture transport patterns. [ABSTRACT FROM AUTHOR]

The gas plume is a direct manifestation of sea cold seep and one of the most significant symbol indicators of the presence of gas hydrate reservoirs. The multibeam water column (MWC) data can be used to extract and identify the gas plume efficiently and accurately. The current research methods mostly start from the perspective of image theory, which cannot identify the three-dimensional (3D) spatial structure features of gas plumes, reducing the efficiency and accuracy of detection. Therefore, this paper proposes a method for identifying and extracting the gas plume based on an MWC point cloud model, which calculates the spatially resolved homing of MWC data and constructs a 3D point cloud model of MWC containing acoustic reflection intensity information. It first performs noise suppression of the 3D point cloud of the MWC based on the symmetric subtraction and Otsu algorithm by leveraging the noise distribution of the MWC and the reflection intensity characteristics of the gas plume. Then, it extracts the point cloud clusters containing the gas plume based on Density-Based Spatial Clustering of Applications with Noise (DBSCAN) according to the density difference between the gas plume point cloud and the background MWC point cloud and next identifies the point cloud clusters by feature matching based on fast point feature histograms (FPFHs). Finally, it extracts the gas plume point cloud set in the MWC. As evidenced by the MWC data collected from gas hydrate enrichment zones in the Gulf of Mexico, the location of gas plume extracted by this method is highly consistent with that of gas leakage points measured during the cruise. Using this method, we obtained the point cloud data set of gas plume for the first time and accurately characterized the 3D spatial morphology of the subsea gas plume, providing technical support for gas hydrate exploration, subsea gas seepage area delineation, and subsea seepage gas flux estimation. [ABSTRACT FROM AUTHOR]

The thin layers in the ocean are temporally-coherent aggregations of phytoplankton with high concentrations at small vertical scales, presenting important hotspots of ecological activity. Lidar could identify thin phytoplankton layers at a large spatial scale due to its capabilities of profile detection with a high efficiency. However, studies that linked thin layers to environmental factors are few, which limits our understanding of the layer formation mechanism. This paper investigates the characteristics and formation conditions of thin phytoplankton layers in the northern Gulf of Mexico using airborne lidar. The results depict that the chlorophyll concentration determines the formation probability of the phytoplankton layer. The layer is mainly formed at concentrations less than 6 mg m−3 and mostly distributed at 2 mg m−3. In addition, layer thicknesses were within 5 m and layer depths were mainly in the range of 10–15 m. Layer depths in the nearshore region were shallower than those in the offshore region. We conclude that the characteristics and formation conditions of the thin phytoplankton layers depend on the nutrients and light that are related to the seabed topography, turbidity, eddies and upwelling. The findings of this paper will enhance the understanding of layer formation mechanisms. [ABSTRACT FROM AUTHOR]

This collection of papers provides insights into methods and data currently available to quantify the benefits associated with estuarine habitat restoration projects in the northern Gulf of Mexico, USA, with potential applicability to other coastal systems. Extensive habitat restoration is expected to occur in the northern Gulf of Mexico region over the next several decades through funding associated with the 2010 Deepwater Horizon oil spill. Papers in this section examine the development of vegetation, soil properties, invertebrate fauna, and nekton communities in restored coastal marshes and provide a conceptual framework for applying these findings to quantify the benefits associated with compensatory marsh restoration. Extensive meta-analysis of existing data for Gulf of Mexico coastal habitats further confirms that structured habitats such as marsh, submerged aquatic vegetation, and oyster reefs support greater nekton densities than nonvegetated bottom habitat, with oyster reefs supporting different species assemblages than marsh and submerged aquatic vegetation. Other papers demonstrate that while vegetation cover can establish rapidly within the first 5 years of restoration, belowground parameters such as root biomass and soil organic matter remain 44% to 92% lower at restored marshes than reference marshes 15 years after restoration. On average, amphipod and nekton densities are also not fully restored until at least 20 and 13 years following restoration, respectively. Additional papers present methods to estimate the benefits associated with marsh restoration projects, nekton productivity associated with coastal and estuarine habitats, and the benefits associated with the removal of derelict crab traps in Gulf of Mexico estuaries. [ABSTRACT FROM AUTHOR]

The Gulf of Mexico (GOM) is a semi-closed basin that supports high marine biodiversity, and is also an important economic area where the Exclusive Economic Zones (EEZs) of the United States, Mexico and Cuba converge. Twenty-one species of cetaceans are commonly sighted in the GOM, and although the population traits of most species are well known in the U.S. EEZ, the development of regional management plans complicated because of the apparent lack of ecological data in the Mexican EEZ, which comprises about 50% of the entire GOM. The state of knowledge of cetaceans in Mexican waters was reviewed to identify current research trends and gaps. The results clearly show that the Mexican research effort is focused on a few coastal popu- lations of a single species, the bottlenose dolphin Tursiops truncatus), while the offshore cetacean populations are ignored; therefore, there are insuf- ficient data to assess diversity, distribution, and abundance. Moreover, due to the high mobility of cetaceans and the transboundary nature of their ranges, the scientific community is currently not prepared to detect population trends in cetacean populations of the GOM. To accomplish this, two priorities were identified: (1) to expand and refo- cus the Mexican research capabilities, and (2) to implement binational monitoring programs. [ABSTRACT FROM AUTHOR]

Over the past decade, Multibeam Echosounders (MBES) have become one of the most used techniques in sea exploration. Modern MBES are capable of acquiring both bathymetric information on the seafloor and the reflectivity of the seafloor and water column. Water column imaging MBES surveys acquire significant amounts of data with rates that can exceed several GB/h depending on the ping rate. These large file sizes obtained from recording the full water column backscatter make remote transmission difficult if not prohibitive with current technology and bandwidth limitations. In this paper, we propose an algorithm to decorrelate water column and bathymetry data, focusing on the KMALL format released by Kongsberg Maritime in 2019. The pre-processing stage is integrated into FAPEC, a data compressor originally designed for space missions. Here, we test the algorithm with three different datasets: two of them provided by Kongsberg Maritime and one dataset from the Gulf of Mexico provided by Fugro USA Marine. We show that FAPEC achieves good compression ratios at high speeds using the pre-processing stage proposed in this paper. We also show the advantages of FAPEC over other lossless compressors as well as the quality of the reconstructed water column image after lossy compression at different levels. Lastly, we test the performance of the pre-processing stage, without the constraint of an entropy encoder, by means of the histograms of the original samples and the prediction errors. [ABSTRACT FROM AUTHOR]

Information on recreation site amenities is often sparse. Not only does this information scarcity have the potential to limit recreation activity, particularly if it causes users to forego recreation opportunities, but it also limits the ability of coastal communities to best allocate resources across site amenities to meet the needs of current and potential users and maximize the value of marine resources. In this paper, we estimate travel cost models that make use of a new dataset on fishing site characteristics to investigate the degree to which a large vector of amenities influences the site choice decisions of recreational anglers fishing in the Gulf of Mexico. We also uncover an important role of racial, ethnic, and income diversity considerations in recreation decision-making. We contextualize the valuation estimates, and combined with the findings of angler tendencies to avoid diversity, discuss the implications for coastal resource management. [ABSTRACT FROM AUTHOR]

The Bureau of Safety and Environmental Enforcement (BSEE) has collected decommissioning expenditure data from operators in the US Gulf of Mexico since 2016 to estimate the decommissioning liability of federal leases. BSEE uses the collected data to estimate the expected decommissioning cost for every active wellbore, structure, and pipeline segment in federal waters but does not otherwise disclose the statistical results of their data collection efforts or methods employed in cost estimation. The task of this paper is to summarise BSEE decommissioning cost estimates in the shallow water US Gulf of Mexico for each of the main decommissioning stages and to infer unit cost statistics and cost functions in the region. Fixed platform removals are expected to cost on average $977,000 in water depth less than 30 m and up to $3.6 million in water depth from 61 to 122 m, about three times more expensive than caisson removals in similar water depth. [ABSTRACT FROM AUTHOR]

The Sustainable Development Goals Science Satellite-1 (SDGSAT-1) Glimmer Imager for Urbanization (GIU) data is very sensitive to low radiation and capable of detecting weak light sources from vessels at night while significantly improving the spatial resolution compared to similar products. Most existing methods fail to use the relevant characteristics of vessels effectively, and it is difficult to deal with the complex shape of vessels in high-resolution Nighttime Light (NTL) data, resulting in unsatisfactory detection results. Considering the overall sparse distribution of vessels and the light source diffusion phenomenon, a novel vessel detection method is proposed in this paper, utilizing the high spatial resolution of the SDGSAT-1. More specifically, noise separation is completed based on a local contrast-weighted RPCA. Then, artificial light sources are detected based on a density clustering algorithm, and an inter-cluster merging method is utilized to realize vessel detection further. We selected three research areas, namely, the Bohai Sea, the East China Sea, and the Gulf of Mexico, to establish a vessel dataset and applied the algorithm to the dataset. The results show that the total detection accuracy and the recall rate of the detection algorithm in our dataset are 96.84% and 96.67%, which is significantly better performance than other methods used for comparison in the experiment. The algorithm overcomes the dataset's complex target shapes and noise conditions and achieves good results, which proves the applicability of the algorithm. [ABSTRACT FROM AUTHOR]

Presents a response by S. B. Joye et al to the comments on their paper "Geohysical and Geochemical Signatures of Gulf of Mexico Seafloor Brines," which appeared in the 2005 issue of "Biogeosciences Discussions." Questions raised about the thermal stratification and chemical distribution data for the brine pools; Purpose of brine trapper positioning; Implication of the temperature profiles shown for the brine pool site.

Offshore facilities are essential infrastructure systems for many nations because their partial or total interruption causes diverse consequences in the economic, political, environmental, and social sectors. With the aim to preserve such structures at acceptable reliability levels, an approach is proposed to calculate the optimal instant of time in which inspection and maintenance works can be performed. The optimal time instant is estimated following the cost benefit criterion (CB) considering the cost of inspection, repair and failure. The inspection cost is given by an inspection quality, while fatigue crack size at different critical joints is calculated to estimate repair costs. In this paper, the concept of demand exceedance rates is introduced to evaluate the failure cost. Uncertainties related to both storm and operational waves are considered. The optimal time instant is associated with the lowest cost of inspection, repair and failure. For this purpose, the approach is exemplified in an offshore jacket structure situated in the Gulf of Mexico. The optimal instant of time corresponds to 6 years after the offshore jacket installation. If maintenance actions are implemented every six years during the lifespan of the system, an economic reduction of 58% is achieved, compared to the case in which no inspection and maintenance works are performed over time. The approach helps decision-makers ensure the best use of economic resources. [ABSTRACT FROM AUTHOR]

Coastal ecosystems are complex and often support a broad spectrum of functions with competing objectives. In addition to their ecological value, they offer socio-economic benefits (i.e., ecosystem services) to coastal communities. One potential way to help address this complexity is to use decision support systems to help natural resources managers understand system dynamics and evaluate strategies to maintain the health and integrity of these ecosystems. This paper presents a roadmap and detailed application of co-production strategies where managers and researchers are fully engaged in a collaborative manner in the design of a decision support tool for coastal ecosystems. It also emphasizes the importance of capturing end-users' (i.e., natural resource managers) priorities to refine the conceptual design of the decision support tool, while maintaining a sound scientific and modeling framework. The case study presented here centers on the Northern Gulf of Mexico, but the concept can be exported globally to other systems. This effort highlights foundational co-production strategies, including transdisciplinary team assembly, a knowledge sharing workshop, Toolbox Dialogue Initiative workshops to facilitate working across disciplines, core team and focus group meetings, and design charrettes. Further, this paper articulates the benefits and difficulties of executing a co-production process through virtual collaborations. • Coastal ecosystem management by co-productive, interdisciplinary design methods. • Co-production design strategies for decision support systems. • Northern Gulf of Mexico natural resource management decision support tool. [ABSTRACT FROM AUTHOR]

The recycling or burial of carbon dioxide in depleted petroleum reservoirs and re-imagining exploration strategies that focus on hydrogen reservoirs (with any associated hydrocarbon gas as the upside potential) are a necessity in today's environmental and geopolitical climate. Given that geologic hydrogen and hydrocarbon gases may occur in the same or different reservoirs, there will be gains in efficiency when searching for both resources together since they share some commonalities, but there is no geophysical workflow available yet for this purpose. Three-dimensional (3D) marine controlled-source electromagnetic (CSEM) and magnetotelluric (MT) methods provide valuable information on rock-and-fluid variations in the subsurface and can be used to investigate hydrogen and hydrocarbon reservoirs, source rocks, and the migration pathways of contrasting resistivity relative to the host rock. In this paper, a process-oriented CSEM-MT workflow is proposed for the efficient combined investigation of reservoir hydrocarbon and hydrogen within a play-based exploration and production framework that emphasizes carbon footprint reduction. It has the following challenging elements: finding the right basin (and block), selecting the right prospect, drilling the right well, and exploiting the opportunities for sustainability and CO2 recycling or burial in the appropriate reservoirs. Recent methodological developments that integrate 3D CSEM-MT imaging into the appropriate structural constraints to derive the geologically robust models necessary for resolving these challenges and their extension to reservoir monitoring are described. Instructive case studies are revisited, showing how 3D CSEM-MT models facilitate the interpretation of resistivity information in terms of the key elements of geological prospect evaluation (presence of source rocks, migration and charge, reservoir rock, and trap and seal) and understanding how deep geological processes control the distribution and charging of potential hydrocarbon, geothermal, and hydrogen reservoirs. In particular, evidence is provided that deep crustal resistivity imaging can map serpentinized ultramafic rocks (possible source rocks for hydrogen) in offshore northwest Borneo and can be combined with seismic reflection data to map vertical fluid migration pathways and their barrier (or seal), as exemplified by the subhorizontal detachment zones in Eocene shale in the Mexican Ridges fold belt of the southwest of the Gulf of Mexico, raising the possibility of using integrated geophysical methods to map hydrogen kitchens in different terrains. The methodological advancements and new combined investigative workflow provide a way for improved resource mapping and monitoring and, hence, a technology that could play a critical role in helping the world reach net-zero emissions by 2050. [ABSTRACT FROM AUTHOR]

Nowadays, there is great concern about obtaining clean energy. Governments around the world are boosting renewable energy resources. Oceans provide abundant renewable energy resources, including tidal, wave, and current energy. It seems that ocean currents are one of the most promising ways to obtain energy from the oceans. The goal of this paper is to assess the hydrokinetic power potential in three different areas of the Spanish coast using a novel turbine design, named the fin-ring turbine. The patented turbine was previously power tested in 2014 in the Gulf of Mexico and numerically validated in the literature. A three-dimensional computational fluid dynamics (CFD) simulation of the novel current turbine is presented, including mesh sensitivity and turbulence studies. The turbine's performance represented in TSR-Cp is discussed. The turbine was simulated in different regions with several current speeds, focusing on the Spanish coast. The results are very promising, with upper limit power coefficients of 37.5%, and 36.5% as a lower limit. Also, the comparisons with power test data available in the literature show very satisfactory agreement. The results highlight the superiority of the turbine in lower currents and present the suitability of the turbine's applicability. [ABSTRACT FROM AUTHOR]

The proliferation of drilling expeditions focused on characterizing natural gas hydrate as a potential energy resource has spawned widespread interest in gas hydrate reservoir properties and associated porous media phenomena. Between 2017 and 2019, a Special Section of this journal compiled contributed papers elucidating interactions between gas hydrate and sediment based on laboratory, numerical modeling, and field studies. Motivated mostly by field observations in the northern Gulf of Mexico and offshore Japan, several papers focus on the mechanisms for gas hydrate formation and accumulation, particularly with vapor phase gas, not dissolved gas, as the precursor to hydrate. These studies rely on numerical modeling or laboratory experiments using sediment packs or benchtop micromodels. A second focus of the Special Section is the role of fines in inhibiting production of gas from methane hydrate, controlling the distribution of hydrate at a pore scale, and influencing the bulk behavior of seafloor sediments. Other papers fill knowledge gaps related to the physical properties of hydrate‐bearing sediments and advance new approaches in coupled thermal‐mechanical modeling of these sediments during hydrate dissociation. Finally, one study addresses the long‐standing question about the fate of methane hydrate at the molecular level when CO2 is injected into natural reservoirs under hydrate‐forming conditions. Key Points: The arc of laboratory and modeling research focused on hydrate‐bearing sediments has been based on the findings of major field programsThe Special Section highlights hydrate formation from vapor phase methane in porous media and the role of fines in hydrate reservoirsThe Special Section underscores the importance of coupled mechanical and thermodynamic models for tracking gas hydrate reservoir evolution [ABSTRACT FROM AUTHOR]

Ocean monitoring is an expensive and time consuming endeavor, but it can be made more efficient through the use of teams of autonomous robots. In this paper, we present a system for the autonomous identification and tracking of ocean fronts by coordinating the sampling efforts of a heterogeneous team of autonomous surface vehicles (ASVs) and autonomous underwater vehicles (AUVs). The primary contributions of this study are (1) our algorithm for performing autonomous coordination using general autonomy principles: Sequential Allocation Monte Carlo Tree Search (SA‐MCTS) which incorporates domain knowledge into the environmental estimation through both augmenting a standard Gaussian process with a nearest neighbors prior and planning in a drifting reference frame, (2) our decision support user interface to help human operators oversee the autonomous system, and (3) the demonstration of the system's operation in a 2‐week long deployment in the Gulf of Mexico using a heterogeneous team of four Slocum gliders and two robotic ocean surface samplers. With these contributions, we aim to bridge the gap between state of the art autonomy algorithms and marine vehicle planning methods that have been tested in large‐scale field trials. This paper presents the first deployment of a general, heuristic‐based, multi‐robot coordination algorithm for an extended sampling mission. [ABSTRACT FROM AUTHOR]