Article

Temporal variability of marine debris deposition at Tern Island in the Northwestern Hawaiian Islands

Authors:
  • U.S. All Islands Coral Reef Committee (on contract with The Baldwin Group, Inc.)
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... The aspect of a coastline affects its exposure to swell and wind, which in turn affects the daily arrival rate of marine debris (Blickley et al., 2016;Eriksson et al., 2013). Seasonal rainfall that affects urban runoff (Cheung et al., 2016) as well as changes in ocean currents (Agustin et al., 2015;Ribic et al., 2012) can significantly affect coastal debris loads. Stokes drift is the capacity of wave transport to move a suspended object (Bever et al., 2011). ...
... This cannot be accounted for by the exposure of study sites to swell or wind (Tables 1, 2), and so is likely due to changes in the offshore debris load. The seasonal change in debris loads may be due to larger scale shifts in the local oceanography (Agustin et al., 2015;Ribic et al., 2012), reduced urban plumes from record-breaking low urban runoff in winter 2017 (BOM, 2017c;Cheung et al., 2016) or lesser maritime use in winter (Critchell et al., 2015). ...
... The diversity of debris composition with substrate reinforces the need to study individual debris items and their characteristics, to identify where they would most likely be retained on shore. Furthermore, future studies would benefit from examining the role of regional scale oceanographic and social factors that may affect the temporal distribution of debris (sensu Agustin et al., 2015;Rudduck et al., 2017). ...
Article
For decades, community groups and scientists have sampled coastal waste along shorelines to understand the distribution of debris. However, when debris is washed ashore or locally deposited, it may be washed away before it is removed or recorded. Using statistical models to understand the movement of debris in coastal processes may identify potential sinks of anthropogenic debris. We modelled arrival and departure of debris using data from repeated removal and marking experiments. Both the arrival and departure of debris were affected by the substrate of the shoreline and by seasonal changes (e.g. autumn and winter). Different substrates accumulated different types of debris. The backshore, coastal shape and wind exposure had all affected the departure but not the arrival of debris. Our findings suggest that areas with high accumulation have lower departure, rather than higher arrival of debris. The implication is that counting debris in dirty locations, as when cleanup activities are used for monitoring, will provide a misleading measure of the actual debris in adjoining waters. We found that onshore winds and lower profile backshore vegetation increase the departure of debris. Debris may be moving inland and accumulating in the backshore vegetation, suggesting the backshore vegetation could be a substantial sink of missing marine debris. Overall, inferring the state of plastic pollution in the ocean using one “snapshot” on shore may underestimate the output of debris from land-based sources, whilst overestimating ocean loads near sites that retain or accumulate high levels of debris.
... Temporal changes of AMD have been studied over different spatial scales, but most of them have been done on a small scale, such as single beaches, bays or islands (e.g. Agustin et al., 2015;Tourinho and Fillmann, 2011), or during shorter periods of time (e.g. Madzena and Lasiak, 1997;Storrier et al., 2007). ...
... Those studies cover wide spatial scales, from a single beach or island (e.g. Agustin et al., 2015;Walker, 1997) up to a continental scale (Ribic et al., 2011;Schulz et al., 2015b), and a wide range of temporal extensions, with a time frame of 2 to 25 years (e.g. Ribic, 1998;Schulz et al., 2015a). ...
... Eastman et al., 2013), and consequently AMD densities. Also, in some cases AMD variations were associated with oceanographic seasonal patterns, such as El Niño events (Gago et al., 2014;Morishige et al., 2007), and wind-induced drift and wave action (Agustin et al., 2015). These records show that AMD abundances are highly variable over time and are strongly affected by the local context of each study, particularly by a combination of social and oceanographic factors. ...
Article
We examined the hypothesis that in an emerging economy such as Chile the abundances of Anthropogenic Marine Debris (AMD) on beaches are increasing over time. The citizen science program Científicos de la Basura (“Litter Scientists”) conducted three national surveys (2008, 2012 and 2016) to determine AMD composition, abundance, spatial patterns and temporal trends. AMD was found on all beaches along the entire Chilean coast. Highest percentages of AMD in all surveys were plastics and cigarette butts, which can be attributed to local sources (i.e. beach users). The Antofagasta region in northern Chile had the highest abundance of AMD compared with all other zones. Higher abundances of AMD were found at the upper stations from almost all zones. No significant tendency of increasing or decreasing AMD densities was observed during the 8 years covered by our study, which suggests that economic development alone cannot explain temporal trends in AMD densities.
... Microplastics are also accumulating on oceanic islands in the currents or recirculation associated with mesoscale activity. The direct link between AML arrival on oceanic islands and the nearby subtropical gyre has also been highlighted (Agustin, Merrifield, Potemra, & Morishige, 2015), especially for those islands with predominant wind and current directions that favour the accumulation of AML (e.g. Lavers & Bond, 2017). ...
... The estimate of the level of threat to the MPAs by AML might, therefore, consider the distance from the main sources of contamination (see Robinson et al., 2017), the mean surface oceanic circulation that constitutes the main routes of AML at seasonal and interannual timescales (e.g. Agustin et al., 2015), and also the relative amplitude of the eddy flow that can sporadically (but steadily) diffuse AML to the surrounding regions of the main AML accumulation zones. This is particularly the case for S&G Island at a distance of~526 km to the north-west of the South Pacific Subtropical Gyre (Table 1). ...
... This activity alongside with impromptu beach clean-ups are becoming habitual and their unpredictability could add bias into assessments of litter deposition for sandy beaches in particular (Moore et al., 2001). Furthermore, litter abundance and typology on the coastline is known to be guided by a complex combination of various factors but also proximity to urban centres (Leite et al., 2014;Nelms et al., 2017); proximity to water streams (Wagner and Lambert, 2018); exposure to oceanic currents (Bouwnman et al., 2016), winds (Walker et al., 2006;Browne et al., 2010;Agustin et al., 2015;Schmuck et al., 2017) or beach orientation, slope and geomorphology (Critchell et al., 2015;Willis et al., 2017). ...
... Widmer and Hennemann, 2010;Thiel et al., 2013;Leite et al., 2014;Moriarty et al., 2016) including in oceanic islands of the Atlantic (Widmer and Hennemann, 2010;Monteiro et al., 2018) and of the Pacific (e.g. Agustin et al., 2015;Blickley et al., 2016;Ribic et al., 2012, Lavers and. Plastic fragments of different sizes were the most abundant plastic items found throughout the archipelago, similarly to what was found on the beach of a remote island of the Pacific and on the windward beaches of Aruba in the Caribbean (De Scisciolo et al., 2016). ...
Article
Marine litter has been identified as one of the major environmental problems that oceans are currently facing. Worldwide efforts are being made to reduce the input of litter into the oceans, and projects aimed at monitoring their quantities are key to evaluate their success. This study, provide baseline information on the quantities of marine litter found on 42 beaches spread throughout the nine islands of the Azores archipelago, North Atlantic Ocean. A total of 31,439 items were collected throughout the archipelago with an average density of 0.62 ± 0.15 macro-litter items m −2. Of this litter 87% were plastic and its majority (67%) plastic fragments. Six beaches were further monitored every three months for two years. Substrate type and wind exposure were important factors for explaining patterns of litter deposition. Our results highlight that marine litter have the tendency to accumulate in remote islands of the North Atlantic Ocean.
... As well as the conditions at the location, it is also important to take into consideration the varying origin, distribution and behaviour of the different sizes of the plastic objects or fragments, as these differ across locations. Regional variations on plastic types and sizes are thought to occur 79 due to variety in the composition of local sources 83,84 . ...
Technical Report
It presents an assessment of the feasibility of removing plastics from the oceans in large quantities, and identifies the challenges that must be overcome to create an environmentally, economically, and legally workable system for removal of ocean plastics. It also suggests possible next steps towards achieving such a removal system. This report does not present new work, but is based on a thorough assessment of scientific and other literature.
... A significant number of factors determine litter content and amount, including natural processes such as erosion, local tidal range [73][74][75], currents and storm occurrence [24,27,30,37,58,64,76,77], beach characteristics [78,79], and wind direction and strength [24,27,30,36,46,58,64,65,73,[80][81][82]. Significant positive correlations were observed in the abundance by number of items with rainy days, rainfall, and river discharge [17,32,58,81,[83][84][85][86][87] and runoff [46,81,83]. ...
Article
Full-text available
Studies analyzing large-scale patterns or long-term trends in the amounts and composition of beach litter are often based on the analysis of several small-scale studies, which may provide an inaccurate picture if the methods and approaches used in those studies are not directly comparable. Moreover, most beach-litter review studies do not evaluate how the results are affected by a number of factors. Therefore, this paper analyzes empirical results from 62 beach-litter (BL) assessment studies published in the last decade (years 2010–2020) in peer-reviewed international journals. Both the results on beach litter (origin, composition, and density) and the utility of those findings to coastal managers are analyzed and discussed. The paper identifies strengths and weaknesses of different research designs, overall compatibility among the results of studies, and identification and means of eliminating those aspects that cause incompatibilities, inconsistencies, and high variability of data that cause low reliability of the results, among other issues. The results indicate that a global picture based on a number of small-scale studies cannot be drawn due to incompatibilities in sampling protocols and presentation of results, data analysis and interpretation, spatial and temporal differences, and the lack of understanding of factors influencing BL. This paper offers a critical view of many aspects of (BL) research in order to bring them to researchers’ attention, at the same time recognizing the importance of previously published studies in making significant advancements in this field. Finally, it is also a call to move from limited data collecting and presentation in peer-reviewed journals to experimental designs, large data analyses, and testing of methods and solutions to the BL issue to advance understanding of beach-litter issues.
... In terms of abundance and weight, the MD on the Bali Island southern coast is lower, higher, and almost the same as previous studies worldwide that used a similar survey method (Table 2). It is due to differences in local dynamic conditions at each study location (Browne et al., 2015), such as rainfall (Ryan and Perold, 2021), season (Cheung et al., 2016;Shimizu et al., 2008), flood events (Topçu et al., 2013), river discharge (Krelling and Turra, 2019), typhoon/storms (Smith and Markic, 2013;Swanson et al., 2016), waves (Pieper et al., 2015), surface current (Agustin et al., 2015;Kako et al., 2018;Kubota, 1994;, tides (Lorenzi et al., 2020;van Emmerik et al., 2020), wind, bathymetry (Ambrose et al., 2019;Browne et al., 2015), dan tsunami (Hipfner et al., 2018;Matthews et al., 2017;Maximenko et al., 2018). Besides that, geographical circumstances related to human activities such as population density (Schmuck et al., 2017), tourism (Behera et al., 2021;Hoellein et al., 2015;Mghili et al., 2020;Mugilarasan et al., 2021), aquaculture, fisheries (Eastman et al., 2013;Greggio et al., 2018;Thushari et al., 2017), festival (Behera et al., 2021), regular cleaning program (da Silva et al., 2018;Schmuck et al., 2017), and the existence of inadequate management landfills (Ambrose et al., 2019;Witteveen et al., 2017), is also strongly affected the accumulation of stranded MD on the beach. ...
Article
Stranded marine debris (MD) has become a hot topic on Bali Island because it threatens coastal tourism sustainability. This study aims to investigate the spatiotemporal abundance and characteristics of MD on 14 touristic beaches in Bali Island. Sampling is carried out twice every season by adapting methods from NOAA's MD program. We found that the average MD abundance and weight were 0.356 ± 0.366 items/m2 and 4.057 ± 3.892 g/m2, respectively. Plastic dominated the MD based on abundance (86.9%) and weight (40.1%). Plastic bags, straws, and plastic cups are the most common items among plastics. The MD is originated from Indonesia and is dominated by land-based sources. The beaches are categorized as dirty in the rainy seasons and clean in the dry seasons. Statistically, the MD based on abundance, weight, category, source, and level of cleanliness varied significantly between seasons.
... In addition, this is in line with results of Williams et al. (2017) who discuss that winter storms increase the beaching of litter. Similarly, Agustin et al. (2015) related episodic stranding of litter to storm events. ...
Article
Full-text available
Replicate surveys of beach litter have seldom been performed in the past. In this study, replicate surveys of beach litter were conducted on the beach north of Hörnum (Sylt, Germany), from 2015 to 2019, applying a slightly modified OSPAR protocol of beach litter monitoring. Descriptive statistics and power analyses were calculated on data resulting from these replicate surveys, to find out whether the scatter of replicate beach litter data decreases and the statistical power increases with increasing numbers of replicate surveys. From 2015 to 2019, mean total abundances, given as numbers of litter items, ranged from 19 to 185 litter items on a 50 m section of beach. With increasing numbers of replicate surveys, the scatter given by the coefficient of variation (CV) significantly increased up to 113%. Statistical power considerably increased with increasing numbers of replicate beach sections, e.g. from 82% (two beach sections) to nearly 100% (five beach sections) for a given reduction of beach litter of 50%. Based on these results from a morphologically straight coastline, the use of replicate surveys would be sensible for the future monitoring of beach litter. However, there is high need for studies, which consider coastlines with varying morphology.
... In the Black Coast Sea, Topçu et al. (2013) observed a high density on autumn and winter while Simeonova et al. (2017) recorded a higher density in summer compared to other seasons. Analysis of the temporal variation in debris density showed significant changes over the same part of the beach (Hong et al., 2014;Agustin et al., 2015) up to a continental scale (Schulz et al., 2015). Debris abundance is highly variable over time and is strongly influenced by the local context of each study (Browne et al., 2015). ...
Article
Morocco is well known for its attractive Mediterranean beaches, which play an important economic role. With the fast development and growth, these beaches have become more contaminated by marine debris. This paper examined the abundance, composition and marine debris sources on five beaches in the Moroccan Mediterranean during 2019 four seasons. A total of 7839 marine debris were collected from the five beaches with a total weight of 231 kg. The average density of the debris collected was 0.20 ± 0.098 items/m². Polymer materials constituted the majority of debris found, with a percentage of 71.36%, followed by paper/cardboard (11.50%), metal (5.77%), processed wood (5.34%), cloth/textile (2.51%) and glass/ceramics (1.76%). Human recreational activities were the main source of debris (70.13%), followed by smoking-related (13.98%). Debris density appears to be particularly influenced by beach users. Awareness campaigns are needed for beach users to improve the quality of the beaches.
... This has subsequently doubled, but without data on waste management or any beach cleaning activities in the interim, it is not possible to determine whether this is a genuine increase in the ratio of plastic waste or merely an accumulation of longlasting material on open beaches. Beach litter found on other remote islands around the world is also predominantly plastic items (Merrell, 1980;Benton, 1995;Agustin et al., 2015;Lavers and Bond, 2017;Krishnakumar et al., 2020). The dominance of hard plastic was also observed in mainland Korean beaches, although the source of hard plastic there was considered mostly from daily recreational activities rather than fishing (Lee et al., 2017). ...
Article
The objective of this study was to obtain baseline data on litter from three beaches of the Lakshadweep Islands (Kadmat, Suheli Par, and Minicoy). At each site, three transects of 20 × 20 m of the foreshore and intertidal zone were sampled during low tide. All macro litter (size >2.5 cm to <1 m) within each transect were collected and counted. A total of 1231 litter items belonging to 22 categories were recorded. The highest average abundance (193 ± 97 items/400 m 2) of marine litter was found in Kadmat, followed by Suheli Par (154 ± 31items/400 m 2) and Minicoy (63 ± 49 items/400 m 2) islands. The Clean Coast Index (CCI) suggests that Minicoy Island has a clean beach (CCI 3.15) while Suheli Par (CCI 8) and Kadmat (CCI 10) were moderate. The primary contributing sources of litter on the beaches were fishing (45%) and public (34%). Better management practices are required to control litter sources.
... For example, the Tern Island in the Northwestern Hawaiian Islands, one of the most remote archipelagos in the world, is part of the Papaha̅ naumokua̅ kea Marine National Monument and is therefore under restrict legislation and has very limited human occupation (as well as limited local sources of marine litter). However, the region faces chronic problems associated with marine litter from sea-based sources (i.e., boats, aquaculture, shipping) (Agustin et al., 2015). The studies on islands with special legal status, such as Biosphere Reserves, have also reported threats associated with marine litter. ...
Article
The Albuquerque atoll was studied as a representative natural laboratory to explore the role of sea-based sources of marine litter. This work aimed to identify the small-scale spatial distribution of marine litter (i.e., plastic, glass, paper, and others) as well as to explore the connectivity among the atoll habitats (sand beach, water surface, and reef) to give insights of potential sources of marine litter (> 5 cm), mainly plastics. Marine litter was dominated by plastic items, as expected, with an average value of 0.5 items/m 2. Large microplastics (1-5 mm) were also sampled on beaches with an average value of 90 particles/m 2. In the atoll inner lagoon, marine litter was also composed by plastic, mainly fragments (average 0.059 items/m 3). The predominance of plastic fragments on both the sea surface and beaches of the atoll makes inferences on sources limited. However, o fishing activities and sea-based sources might be relevant since local sources are very limited.
... Worldview-2, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Synthetic Aperture Radar (SAR) satellite datasets have been efficiently employed in monitoring marine plastic debris events, for instance, after the great east Japan earthquake on March 2011, when a remarkable amount of >1.5 million tonnes of debris was generated [20,21]. Satellite data coupled with ocean models have also been employed to investigate the temporal variability of marine debris, its anthropogenic sources [22,23] and its accumulation patterns [24]. Regardless of the benefits exploiting such cost-effective tools, there are indeed limited studies utilizing high-spatiotemporal-resolution satellite-derived information from contemporary sensors. ...
Article
Full-text available
Plastic debris in the global ocean is considered an important issue with severe implications for human health and marine ecosystems. Here, we exploited high-resolution multispectral satellite observations over the Bay Islands and Gulf of Honduras, for the period 2014-2019, to investigate the capability of satellite sensors in detecting marine plastic debris. We verified findings with in situ data, recorded the spectral characteristics of floating plastic litter, and identified plastic debris trajectories and sources. The results showed that plastic debris originating from Guatemala’s and Honduras’ rivers (such as Motagua, Ulua, Cangrejal, Tinto and Aguan) ends up in the Caribbean Sea, mainly during the period of August to March, which includes the main rainfall season. The detected spatial trajectories indicated that floating plastic debris travels with an average speed of 6 km d-1, following primarily a southwest (SW) to northeast (NE) direction, driven by the prevailing sea surface currents. Based on several satellite observations, there is no indication of a specific accumulation point, since plastic debris is dispersed by the dynamic circulation in the broader region. Our findings provide evidence that satellite remote sensing is a valuable, cost-effective tool for monitoring the sources and pathways of plastic debris in marine ecosystems, and thus could eventually support management strategies in the global ocean.
... This model had been developed by NOAA to simulate the trajectory and the fate of oil spills. The model is based on input of required data such as weather condition, type, and quantity of oil spilled on which the output represents the best guess of the spill's trajectory (Agustin et al. 2015). The GNOME has been applied by researchers in different areas such as Istanbul (Başar 2010) and India (Remyalekshmi and Hegde 2013). ...
Article
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The Arabian Gulf is considered as a hub for global oil industry. Thus the Arabian Gulf marine environment is under permanent threat from oil spills due to oil exploitation, production, and transportation. Oil pollution poses adverse effects on marine environment, society, and economy. Oil spill incidents that occurred in Bahrain caused damage to marine environment and threatened the vital coastal facilities along the coastline of Bahrain. This study determined the exposure levels of coastal facilities in Bahrain to oil spills. The General NOAA Operational Modeling Environment (GNOME) model was validated and applied to hypothetical oil spill scenarios. The modeling results showed that the coastal facilities on the north-eastern coastline are more probable to be hit by oil spills, while those on the northern coastline are susceptible to receive more quantity of oil. The time required for oil to reach the western coastline is shorter compared to the other coastlines. The modeling outcomes can be utilized in contingency planning, setting the protection priorities and allocation and mobilization of response resources in both governmental and private sectors. The implications of the present study could be applied on a regional scale to ensure an integrated response to combat and or minimize oil pollution in the Arabian Gulf.
... For several decades, beach-cast debris monitoring programs have been conducted around the world to track the magnitude of the problem (Dixon and Cooke, 1977;Rees and Pond, 1995). Results of these monitoring programs, which often rely on citizen scientists (Rosevelt et al., 2013;Hong et al., 2014), reveal that the composition, size, distribution and abundance of marine debris vary both spatially and temporally (Madzena and Lasiak, 1997;Agustin et al., 2015). The variation is caused both by anthropogenic factors such as the distance to point sources of pollution (Jayasiri et al., 2013;Poeta et al., 2014), and by natural factors such as beach substrate type (Moore et al., 2001;Thiel et al., 2013) and the strength and direction of prevailing winds and currents (Storrier et al., 2007;Ribic et al., 2012). ...
Article
We conducted beach-cast debris transect surveys on Triangle Island, British Columbia, Canada in 2012–2017 to (1) establish a baseline against which to track future changes in stranded debris on this small, uninhabited island; and (2) time the arrival in western North America of debris released by the 2011 Tōhoku tsunami. Most (90%) of the six-year total of 6784 debris items tallied was composed of Styrofoam or plastic. The number of debris items peaked in 2014 (waste Styrofoam, rope) and 2015 (waste plastic, wood), and cumulative totals for all debris types were ca. 50% higher in 2014–15 than in 2012–13 and 2016–17. The peaks in 2014–15 probably represented the arrival of the bulk of the tsunami debris, based on close correspondence with forecasting models and debris surveys elsewhere. A fuller understanding of the movement of the Tōhoku tsunami debris will require information from other beach monitoring programs.
... In Hawaii, over 90% of C. mydas were nesting at the French Frigate Shoals inside the U.S. National Wildlife Refuge. Tern Island, where the turtles were sampled in this study, was a tiny island lied in the French Frigate shoals, approximately 490 miles northwest of Oahu (166 • W longitude, 28 • N latitude) [3]. ...
Article
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The Hawaiian green turtle (Chelonia mydas) is on the list of threatened species protected under the U.S. Endangered Species Act in 1978 in large part due to a severe tumor-forming disease named fibropapillomatosis. Chemical pollution is a prime suspect threatening the survival of C. mydas. In this study, PCBs concentrations were determined in 43 C. mydas plasma samples archived on Tern Island. The total PCBs concentration in male C. mydas (mean 1.10 ng/mL) was two times more than that of females (mean 0.43 ng/mL). The relationship between straight carapace length and PCBs concentration in females has also been studied, which was negatively related. To figure out the possible existence of correlations between PCBs and tumor status, we measured the PCBs concentration in turtles with no tumor, moderate or severe tumor affliction. PCBs concentration of two afflicted groups was much higher than the healthy group, suggesting that PCBs may play a role in fibropapillomatosis in Hawaiian green turtle.
... High densities of beach debris along the southeastern coasts of islands are therefore likely to be influenced by inputs from this system, which transports ocean-based debris from offshore shipping and fishing activities and land-based sources elsewhere. Exposure to ocean currents has been highlighted as a primary factor influencing the density of beach debris on a number of islands in the Pacific (Agustin et al., 2015;Dameron et al., 2007;McDermid and McMullen, 2004) as well as previous studies in the Caribbean (Corbin and Singh, 1993;Debrot et al., 1999;Ivar do Sul and Costa, 2007). While leeward beaches may not experience the wind and wave energy from dominant currents, sandy beaches facing a leeward direction have been shown to be natural depositing environments (Ribic et al., 2012;Ryan et al., 2014). ...
Article
Anthropogenic beach debris was recorded during beach surveys of 24 Caribbean islands during April 2014–April 2016. Beach debris was classified according to material type (e.g., polystyrene) and item use (e.g., fishing). Geophysical features (substrate type, beach direction, and human accessibility) of sample sites were recorded in order to investigate their relationship with debris density. Results suggest the density of macro debris (items > 5 mm) is highest on uninhabited, sandy beaches facing a leeward direction. Higher debris quantities on inaccessible beaches may be due to less frequent beach clean ups. Frequently accessed beaches exhibited lower macro, but higher micro debris (items 1–5 mm) densities, possibly due to removal of macro debris during frequent beach clean ups. This suggests that while geophysical features have some influence on anthropogenic debris densities, high debris densities are occurring on all islands within the Caribbean region regardless of substrate, beach direction, or human accessibility.
... Debrot et al., 1999Debrot et al., , 2013do Sul and Costa, 2007;Cheshire et al., 2009;UNEP-CAR/RCU, 2014). These studies have highlighted the environmental pressure exerted by debris may not only vary over time (Agustin et al., 2015), but also vary considerably between locations around an island. Studies ...
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Accumulation of marine (plastic) debris from local land-based and distal marine-based sources along coastlines is a pressing modern issue. Hitherto, assessing the relative contribution of pollution sources through beach surveys is methodologically challenging. We surveyed ten beaches along the leeward and windward coastlines of Aruba (southern Caribbean) to determine differences in macro- and meso-debris densities. Differences were quantified using three metrics: 1) the gradient in macro-debris density away from the waterfront; 2) the proportion of plastic within macro-debris; 3) the meso-:macro-debris ratio. Overall 42,585 macro-debris items and 884 meso-debris items were collected. The density of near-shore macro-debris, proportion of plastic debris herein, and meso-:macro-debris ratio were highest on the windward coastline. These results suggest that southern Caribbean windward coastlines are mainly exposed to debris originating from distal marine-based sources, and leeward coastlines to local land-based sources. Our metrics clearly reflect these differences, providing novel means to survey debris source origin.
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A poluição por lixo flutuante nos ambientes marinhos e costeiros é um grave problema em todo o mundo, causado geralmente pela gestão ineficiente de resíduos nas zonas costeiras, gerandosérios impactos na vida selvagem, como, por exemplo, morte por ingestão de lixo. O presente estudo tem como objetivo analisar, sob uma retrospectiva histórica e perspectivas para o futuro, o problema do lixo flutuante na Baía de Guanabara. Como metodologia,a análise do passado foi realizada partir da revisão bibliográfica e documental. A análise do presente foi baseada em dados de campo quanto aos itens de lixo flutuante coletados em estudos realizados nas praias de Icaraí, Charitas e São Francisco, em Niterói, na Praia do Flamengo, no Rio de Janeiro, e no Manguezal do Parque Natural Municipal Barão de Mauá, em Magé, e em informações atuais sobre as ações em relação ao lixo flutuante. As perspectivas para o futuro se baseiam nos planos de saneamento básico dos municípios localizados no entorno da Baía de Guanabara que estipularam metas para a despoluição da Baía. Desta forma, os resultados obtidos demonstram que, apesar dos esforços dos órgãos públicos para despoluir a Baía de Guanabara, o lixo dos municípios do entorno dela continua a chegar ao estuário. Reforça-se, no entanto, que ainda é cedo para determinar se esses programas serão, de fato, eficazes, poishá muitas ações a serem realizadas envolvendo tanto a conscientização da sociedade como a participação de todos os atores sociais envolvidos.
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This research studied the types and quantity of marine debris in mangrove forests at Bangpu Recreation Center, Muang Samut Prakarn District, Samut Prakan Province. Marine debris was collected from 9 quadrats of 3x3 meters each. Then, all debris was classified by producing activity and source according to the International Coastal Cleanup (ICC) protocol. Sampling debris was collected twice in August 2019 and in April 2020. The result showed that food wrappers and plastic bags were the types of marine debris found the most. The most abundant debris-producing activity was the shoreline and recreational (90.77-96.42%). The most found marine debris was the plastic bags (75.40-90.30%). The amount of stock and a daily flow of marine debris in August 2019 was higher than in April 2020 (p<0.05). The stock of marine debris quantity was 2.06 and 0.44 items/m 2 , respectively. While the amount of daily flow marine debris was 1. 38 and 0. 36 items/ m 2 , a high abundance of marine debris was found near the shoreline. This research provided the framework for future research in this area and the guidelines for prevention, resolving, and reduce the impact arising from the marine debris problems in the future.
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On the Colombian continental shelf, 12 km SW of the municipality of Galerazamba, Department of Bolívar, is the northern-most island of the Colombian Caribbean: Isla Arena. Despite being remote and uninhabited, this island is being affected by one of the most persistent problems in the marine environment: Marine Anthropogenic Litter (MAL). In this first Colombian insular MAL study, a total of 1436 MAL items were collected along Isla Arena, equivalent to an average abundance of 2.87 items/m2. MAL items belong to 54 categories that are grouped in nine material typologies. These typologies include plastic (36 categories), metal (6), glass (3), medical waste (3), machined wood (2), pottery (1), sanitary waste (1), rubber (1) and cloth (1). Isla Arena now is considered as an “Extremely dirty” site in terms of the Clean Coast Index. Hazardous litter items (sharp and toxic) occur in percentages as high as 10.2% (146 items, Avg: 0.29 items/m2). Along the island, current MAL amounts are so elevated that simple clean-up operations are an insufficient solution, and restoration measures are needed. MAL mainly comes from land-based sources, primarily generated by activities in the adjacent mainland river basins and coastal urban developments, particularly in the area of beaches. Marine anthropogenic litter found on Isla Arena reflects a strong influence from longshore-current transport. Management solutions need to begin at the same litter sources, and must include analytics, policy reforms and enforcement, and private and public investments.
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We study the evolution of large systems of sticky patches of pollution that float on the sea surface and are moved around by realistic wind and simulated surface currents. The study area is the Gulf of Finland in the eastern Baltic Sea that hosts extremely heavy cargo and tanker traffic. It is assumed that patches merge at collision. Collisions are enhanced by wind impact that depends on the patch size. We implement a space partitioning algorithm for fast simulations of large systems of >8000 patches and perform a series of simulations with different initial size and location of the patches. The resulting empirical distribution of the number of patches of different size is governed universally by a stretched-exponential power law f(x) = A exp (−xb). This indicates that the evolution of large systems of pollution patches on the sea surface exhibits classic self-organization and scale invariance properties. This may be the key effect explaining how the patchiness of waste in marine environment is formed under the impact of different drivers.
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Located in the north-central Pacific Ocean, Papahānaumokuākea, a part of the Hawaii Archipelago, is an isolated group of small islands and atolls 250 km to the northwest of Hawaii Island. Much of the site is made up of pelagic and deepwater habitats with features such as seamounts and submerged banks, extensive coral reefs and lagoons, and also emergent lands distributed between a number of eroded high islands, pinnacles, atoll islands, and cays. The area has deep cosmological and traditional significance for Hawaiian culture, as it is considered the place where life originates and to where the spirits return after death. It is the second largest marine protected area in the world and is a mixed cultural and natural World Heritage site.
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Nowadays one of the growing global problems is the pollution of the marine environment by human-made plastic litter. Coastal surroundings are likely to gather much of the solid waste released by contemporary factory and city community to the oceans. Waste generation increases proportionally with the rapid growth of the world's industrial production and population. The abundance, composition and potential sources of marine debris were examined and it was demonstrated that the plastic debris is prevalent as a worldwide marine pollutant. The debris characteristics suggested that its primary sources are land-based ones. To determine their sources, methods used the surface current from the analytic model of near-surface ocean currents, facilitated by air stream information and satellite sea level. Owing to inadequate waste management, anthropogenic waste can even pose a threat to the most remote environment. Origin or traceability of trash characterizes prized statistics that can be used to examine and in the end, update our ocean circulation understanding. Consideration of methodologies are needed to realize the pellets dispersal in the beach environment, with special attention on input patterns. In the marine environment, plastic debris floating is faster gone from the surface of ocean to other as-yet undetermined sinks.
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The abundance, composition, and potential sources of marine debris were investigated on remote Alphonse Island, during the austral winter 2013. A total of 4743 items, weighing 142kg, were removed from 1km of windward beach, facing the prevailing southeasterly trade winds. Our study demonstrates the prevalence of plastic debris as a world-wide marine contaminant. Characteristics of the debris suggest it originated primarily from land-based sources. To determine their potential geographic sources we used the Surface Current from Diagnostic model of near-surface ocean currents, forced by satellite sea level and wind data. While preliminary evidence indicated the Southeast Asia to be the main source of the flotsam, the model highlighted Somalia as another potential primary source. Our study concludes that most of the collected debris entered the sea as a result of inadequate waste management and demonstrates how anthropogenic waste can negatively impact even the most remote environments. Copyright © 2015. Published by Elsevier Ltd.
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Significance High concentrations of floating plastic debris have been reported in remote areas of the ocean, increasing concern about the accumulation of plastic litter on the ocean surface. Since the introduction of plastic materials in the 1950s, the global production of plastic has increased rapidly and will continue in the coming decades. However, the abundance and the distribution of plastic debris in the open ocean are still unknown, despite evidence of affects on organisms ranging from small invertebrates to whales. In this work, we synthetize data collected across the world to provide a global map and a first-order approximation of the magnitude of the plastic pollution in surface waters of the open ocean.
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We present an extensive survey of floating plastic debris in the eastern North and South Pacific Oceans from more than 2,500 plankton net tows conducted between 2001 and 2012. From these data we defined an accumulation zone (25 to 41°N, 130 to 180°W) in the North Pacific subtropical gyre that closely corresponds to centers of accumulation resulting from the convergence of ocean surface currents predicted by several oceanographic numerical models. Maximum plastic concentrations from individual surface net tows exceeded 10(6) pieces km(-2), with concentrations decreasing with increasing distance from the predicted center of accumulation. Outside the North Pacific subtropical gyre the median plastic concentration was 0 pieces km(-2). We were unable to detect a robust temporal trend in the dataset, perhaps because of confounded spatial and temporal variability. Large spatio-temporal variability in plastic concentration causes order of magnitude differences in summary statistics calculated over short time periods or in limited geographic areas. Utilizing all available plankton net data collected in the eastern Pacific Ocean (17.4°S to 61.0°N; 85.0 to 180.0°W) since 1999, we estimated a minimum of 21,290 metric tons of floating microplastic.
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Plastic debris has been documented in many marine ecosystems, including remote coastlines, the water column, the deep sea, and subtropical gyres. The North Pacific Subtropical Gyre (NPSG), colloquially called the "Great Pacific Garbage Patch," has been an area of particular scientific and public concern. However, quantitative assessments of the extent and variability of plastic in the NPSG have been limited. Here, we quantify the distribution, abundance, and size of plastic in a subset of the eastern Pacific (approximately 20-40°N, 120-155°W) over multiple spatial scales. Samples were collected in Summer 2009 using surface and subsurface plankton net tows and quantitative visual observations, and Fall 2010 using surface net tows only. We documented widespread, though spatially variable, plastic pollution in this portion of the NPSG and adjacent waters. The overall median microplastic numerical concentration in Summer 2009 was 0.448 particles m(-2) and in Fall 2010 was 0.021 particles m(-2), but plastic concentrations were highly variable over the submesoscale (10 s of km). Size-frequency spectra were skewed towards small particles, with the most abundant particles having a cross-sectional area of approximately 0.01 cm(2). Most microplastic was found on the sea surface, with the highest densities detected in low-wind conditions. The numerical majority of objects were small particles collected with nets, but the majority of debris surface area was found in large objects assessed visually. Our ability to detect high-plastic areas varied with methodology, as stations with substantial microplastic did not necessarily also contain large visually observable objects. A power analysis of our data suggests that high variability of surface microplastic will make future changes in abundance difficult to detect without substantial sampling effort. Our findings suggest that assessment and monitoring of oceanic plastic debris must account for high spatial variability, particularly in regards to the evaluation of initiatives designed to reduce marine debris.
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Two new high-resolution sea surface temperature (SST) analysis products have been developed using optimum interpolation (OI). The analyses have a spatial grid resolution of 0.25° and a temporal resolution of 1 day. One product uses the Advanced Very High Resolution Radiometer (AVHRR) infrared satellite SST data. The other uses AVHRR and Advanced Microwave Scanning Radiometer (AMSR) on the NASA Earth Observing System satellite SST data. Both products also use in situ data from ships and buoys and include a large-scale adjustment of satellite biases with respect to the in situ data. Because of AMSR’s near-all-weather coverage, there is an increase in OI signal variance when AMSR is added to AVHRR. Thus, two products are needed to avoid an analysis variance jump when AMSR became available in June 2002. For both products, the results show improved spatial and temporal resolution compared to previous weekly 1° OI analyses. The AVHRR-only product uses Pathfinder AVHRR data (currently available from January 1985 to December 2005) and operational AVHRR data for 2006 onward. Pathfinder AVHRR was chosen over operational AVHRR, when available, because Pathfinder agrees better with the in situ data. The AMSR– AVHRR product begins with the start of AMSR data in June 2002. In this product, the primary AVHRR contribution is in regions near land where AMSR is not available. However, in cloud-free regions, use of both infrared and microwave instruments can reduce systematic biases because their error characteristics are independent.
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Much of the debris in the near-surface ocean collects in so-called garbage patches where, due to convergence of the surface flow, the debris is trapped for decades to millennia. Until now, studies modelling the pathways of surface marine debris have not included release from coasts or factored in the possibilities that release concentrations vary with region or that pathways may include seasonal cycles. Here, we use observational data from the Global Drifter Program in a particle-trajectory tracer approach that includes the seasonal cycle to study the fate of marine debris in the open ocean from coastal regions around the world on interannual to centennial timescales. We find that six major garbage patches emerge, one in each of the five subtropical basins and one previously unreported patch in the Barents Sea. The evolution of each of the six patches is markedly different. With the exception of the North Pacific, all patches are much more dispersive than expected from linear ocean circulation theory, suggesting that on centennial timescales the different basins are much better connected than previously thought and that inter-ocean exchanges play a large role in the spreading of marine debris. This study suggests that, over multi-millennial timescales, a significant amount of the debris released outside of the North Atlantic will eventually end up in the North Pacific patch, the main attractor of global marine debris.
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During January–May, surface manifestation of multiple, individual basin-scale fronts accentuate the central North Pacific Subtropical Frontal Zone (STFZ) system. The most prominent of these fronts are climatologically located at 32°−34°N and at 28°−30°N latitudes [herein nominally referred to as the ‘Subtropical Front’ (STF) and the ‘South Subtropical Front’ (SSTF), respectively], although considerable interannual variability in both position and intensity is observed. This seasonally dynamic system is also the region typically targeted by the Hawaii-based swordfish (Xiphias gladius) longline fishing fleet, where the presence, position, and strength of the convergent fronts are believed to play a key role with regard to the catch and catch rates of swordfish. Information furnished by a recent series of meridional hydrographic surveys and concurrent satellite remote sensing data elucidate structural patterns and coupling of the physics and biology associated with these fronts. This enables a re-characterization of the spring North Pacific STFZ and offers new insight into the seasonal variability of the phytoplankton dynamics in the subtropical North Pacific.
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ERA-Interim is the latest global atmospheric reanalysis produced by the European Centre for Medium-Range Weather Forecasts (ECMWF). The ERA-Interim project was conducted in part to prepare for a new atmospheric reanalysis to replace ERA-40, which will extend back to the early part of the twentieth century. This article describes the forecast model, data assimilation method, and input datasets used to produce ERA-Interim, and discusses the performance of the system. Special emphasis is placed on various difficulties encountered in the production of ERA-40, including the representation of the hydrological cycle, the quality of the stratospheric circulation, and the consistency in time of the reanalysed fields. We provide evidence for substantial improvements in each of these aspects. We also identify areas where further work is needed and describe opportunities and objectives for future reanalysis projects at ECMWF.
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1] High-resolution satellite measurements of ocean color and surface winds, along with historical in situ data, are used to explore interannual variability in the annual migration of the transition zone chlorophyll front (TZCF) in the central North Pacific Ocean. Significant variations in frontal position and annual range were observed, including a significant southerly displacement during El Niñ o events. This displacement, apparently forced by enhanced surface convergence and vertical mixing in the transition zone, creates vast regions of anomalously high wintertime surface chlorophyll in the North Pacific Subtropical Gyre. A remarkably close correspondence between the positions of the TZCF and the 18°C surface isotherm over a portion of the central North Pacific allows historical temperature data to be used as a proxy for TZCF position. This surface temperature proxy has revealed decadal-scale variability in frontal position, with greater (lesser) annual range and southerly extent following the large-scale 1976– 77 (1998 – 99) climate shifts. Interannual variations in TZCF position could have important implications for the distribution and survival of a number of apex predators that utilize the TZCF as a migratory and foraging habitat.
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Baseline measurements were made of the amount and weight of beached marine debris on Sand Island, Midway Atoll, June 2008-July 2010. On 23 surveys, 32,696 total debris objects (identifiable items and pieces) were collected; total weight was 740.4 kg. Seventy-two percent of the total was pieces; 91% of the pieces were made of plastic materials. Pieces were composed primarily of polyethylene and polypropylene. Identifiable items were 28% of the total; 88% of the identifiable items were in the fishing/aquaculture/shipping-related and beverage/household products-related categories. Identifiable items were lowest during April-August, while pieces were at their lowest during June-August. Sites facing the North Pacific Gyre received the most debris and proportionately more pieces. More debris tended to be found on Sand Island when the Subtropical Convergence Zone was closer to the Atoll. This information can be used for potential mitigation and to understand the impacts of large-scale events such as the 2011 Japanese tsunami.
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Pelagic ecosystem dynamics on all temporal scales may be driven by the dynamics of very specialized oceanic habitats. One such habitat is the basin-wide chlorophyll front located at the boundary between the low chlorophyll subtropical gyres and the high chlorophyll subarctic gyres. Global satellite maps of surface chlorophyll clearly show this feature in all oceans. In the North Pacific, the front is over 8000 km long and seasonally migrates north and south about 1000 km. In the winter this front is located at about 30–35°N latitude and in the summer at about 40–45°N. It is a zone of surface convergence where cool, vertically mixed, high chlorophyll, surface water on the north side sinks beneath warm, stratified, low chlorophyll water on the south side. Satellite telemetry data on movements of loggerhead turtles and detailed fisheries data for albacore tuna show that both apex predators travel along this front as they migrate across the North Pacific. The front is easily monitored with ocean color satellite remote sensing. A change in the position of the TZCF between 1997 and 1998 appears to have altered the spatial distribution of loggerhead turtles. The position and dynamics of the front varied substantially between the 1998 El Niño and the 1999 La Niña. For example, from May to July 1999 the transition zone chlorophyll front (TZCF) remained between about 35°N and 40°N latitude showing very little meandering, whereas in 1998, during the same period, the TZCF exhibited considerable meandering and greater monthly latitudinal movement. Catch rates for albacore were considerably higher in 1998 than in 1999, and we hypothesize that a meandering TZCF creates regions of convergence, which enhances the foraging habitat for apex predators along the front.
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We assessed amounts, composition, and trends of marine debris for the U.S. Pacific Coast and Hawai'i using National Marine Debris Monitoring Program data. Hawai'i had the highest debris loads; the North Pacific Coast region had the lowest debris loads. The Southern California Bight region had the highest land-based debris loads. Debris loads decreased over time for all source categories in all regions except for land-based and general-source loads in the North Pacific Coast region, which were unchanged. General-source debris comprised 30-40% of the items in all regions. Larger local populations were associated with higher land-based debris loads across regions; the effect declined at higher population levels. Upwelling affected deposition of ocean-based and general-source debris loads but not land-based loads along the Pacific Coast. LNSO decreased debris loads for both land-based and ocean-based debris but not general-source debris in Hawai'i, a more complex climate-ocean effect than had previously been found.
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A global ocean circulation model is coupled to a Lagrangian particle tracking model to simulate 30 years of input, transport and accumulation of floating debris in the world ocean. Using both terrestrial and maritime inputs, the modelling results clearly show the formation of five accumulation zones in the subtropical latitudes of the major ocean basins. The relative size and concentration of each clearly illustrate the dominance of the accumulation zones in the northern hemisphere, while smaller seas surrounded by densely populated areas are also shown to have a high concentration of floating debris. We also determine the relative contribution of different source regions to the total amount of material in a particular accumulation zone. This study provides a framework for describing the transport, distribution and accumulation of floating marine debris and can be continuously updated and adapted to assess scenarios reflecting changes in the production and disposal of plastic worldwide.
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The potential for ingestion of plastic particles by open ocean filter feeders was assessed by measuring the relative abundance and mass of neustonic plastic and zooplankton in surface waters under the central atmospheric high-pressure cells of the North Pacific Ocean. Neuston samples were collected at 11 random sites, using a manta trawl lined with 333 u mesh. The abundance and mass of neustonic plastic was the largest recorded anywhere in the Pacific Ocean at 334271 pieces km2 and 5114 g km2, respectively. Plankton abundance was approximately five times higher than that of plastic, but the mass of plastic was approximately six times that of plankton. The most frequently sampled types of identifiable plastic were thin films, polypropylene/monofilament line and unidentified plastic, most of which were miscellaneous fragments. Cumulatively, these three types accounted for 99% of the total number of plastic pieces.
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Floating marine debris, particularly derelict fishing gear, is a hazard to fish, marine mammals, turtles, sea birds, coral reefs, and even human activities. To ameliorate the economic and environmental impact of marine debris, we need to efficiently locate and retrieve dangerous debris at sea. Guided by satellite-derived information, we made four flights north of Hawaii in March and April 2005. During these aerial surveys, we observed over 1800 individual pieces of debris, including 122 derelict fishing nets. The largest debris concentrations were found just north of the North Pacific Transition Zone Chlorophyll Front (TZCF) within the North Pacific Subtropical Convergence Zone (STCZ). Debris densities were significantly correlated with sea-surface temperature (SST), chlorophyll-a concentration (Chla), and the gradient of Chla. A Debris Estimated Likelihood Index (DELI) was developed to predict where high concentrations of debris would be most likely in the North Pacific during spring and early summer.
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The Intergovernmental Oceanographic Commission (IOC) was founded in 1960 as a functionally autonomous body within UNESCO and now includes 124 member states. The IOC promotes marine scientific investigations and related ocean services with a view to learning more about the nature and resources of the oceans and coastal areas. In 1985, the Intergovernmental Oceanographic Commission (IOC) initiated the Global Sea Level Observing System (GLOSS) as an international system to provide high‐quality standardized sea level data from a global network of sea level stations. Some 300 sea level stations maintained by 80 countries have been selected as a GLOSS network to observe large‐scale sea level variations of global implications and to serve as the framework for other regional and scientific programs as well as national practical applications. This article provides a description of the GLOSS and the progress in achieving its objectives, observational network, data exchange, present and new technology for sea level observations and geodetic fixing of tide gauge benchmarks, present and planned activities for preparation of sea level products needed for scientific assessment of sea level variability and changes as well as international structure for GLOSS implementation and co‐ordination, and GLOSS interaction with the Global Ocean Observing System (GOOS). The list of references provides information on the material and publications used for preparation of this article. The author has served as GLOSS Technical Secretary in the Secretariat of IOC since 1985.
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The spatial pattern of twenty-year sea surface height trends from satellite altimetry is placed into the context of historical modes of wind-driven ocean volume redistribution identified in basin-scale, regional averages of tide gauge data. The difference between recent rates of sea level change in northern and southern regions is found to be twice as large and statistically greater than any other twenty-year period during the 20th century. This unique asymmetry in the pattern of sea level change coincides with a departure from a historical mode of volume redistribution between southern regions related to a measure of asymmetry in the Southern Annular Mode. The asymmetry also coincides with a maximum in the rate of global mean sea level rise during recent decades, but the asymmetry is not apparent during an early 20th century maximum in the global rate of similar magnitude.
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The skill of modern wave models is such that the quality of their forecasts is, to a large degree, determined by errors in the forcing wind field. This work explores the extent to which large-scale systematic biases in modelled waves from a third generation wave model can be attributed to the forcing winds. Three different sets of winds with known global bias characteristics are used to force the WAVEWATCH III model. These winds are based on the Australian Bureau of Meteorology's ACCESS model output, with different statistical corrections applied. Wave forecasts are verified using satellite altimeter data. It is found that a negative bias in modelled Significant Wave Height (Hs) has its origins primarily in the forcing, however, the reduction of systematic wind biases does not result in universal improvement in modelled Hs. A positive bias is present in the Southern Hemisphere due primarily to an overestimation of high Hs values in the Southern Ocean storm tracks. A positive bias is also present in the east Pacific and East Indian Ocean. This is due both to the over-prediction of waves in the Southern Ocean and lack of swell attenuation in the wave model source terms used. Smaller scale features are apparent, such as a positive bias off the Cape of Good Hope, and a negative bias off Cape Horn. In some situations, internal wave model error has been compensated for by error in the forcing winds.
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Produces four kinds of current fields at the sea surface in the North Pacific and simulate floating marine debris by those current fields. The first current field is associated with Ekman drift, the second with Stokes drift, the third with geostrophic currents, and the last with all current fields combined. -from Authors
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The Lagrangian motions of floating matter on the sea surface were simulated by using the surface current data based on shipdrift data produced by Meehl. The validity of the simulation was confirmed by comparing the results of the model with the trajectories of satellite tracked drift in the eastern North Pacific observed by Kirwan et al. Some cases which originated in the western North Pacific Ocean were investigated. It was found that drifters set in the ocean during spring quickly migrated to North America on the strong eastward North Pacific currents of the summer season. Trajectories started during autumn showed a loop in the western North Pacific and took more time to arrive in the eastern area of the North Pacific Ocean. Each trajectory that arrived in the eastern area of the North Pacific Ocean, showing a large loop, traveled over a one year interval owing to the large surface current vortex. This vortical sea surface current was driven by the clockwise winds around the atmospheric subtrop...
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Ocean forecasting and oil spill modelling and tracking are complex activities requiring specialised institutions. In this work we present a lighter solution based on the Operational Ocean Forecast Python Engine (OOFε) and the oil spill model General NOAA Operational Modelling Environment (GNOME). These two are robust relocatable and simple to implement and maintain. Implementations of the operational engine in three different regions with distinct oceanic systems, using the ocean model Regional Ocean Modelling System (ROMS), are described, namely the Galician region, the southeastern Brazilian waters and the Texas-Louisiana shelf. GNOME was able to simulate the fate of the Prestige oil spill (Galicia) and compared well with observations of the Krimsk accident (Texas). Scenarios of hypothetical spills in Campos Basin (Brazil) are illustrated, evidencing the sensitiveness to the dynamical system. OOFε and GNOME are proved to be valuable, efficient and low cost tools and can be seen as an intermediate stage towards more complex operational implementations of ocean forecasting and oil spill modelling strategies.
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The main oceanic fronts of the North Pacific are investigated and the principal frontogenetic processesdescribed. Fronts are features of the upper ocean and occur near mass transport and energy flux convergencezones. Frontogenesis in the upper layers of the ocean is strongly dependent upon the configuration of thewind stress field. Temperature and salinity fronts in the upper ocean are not necessarily coincident, nor arethey always accompanied by density fronts. During periods of strong and persistent winds, the upper andlower portions of the front may separate at pycnocline depth by as much as 200 km, suggesting Ekman-typedisplacement of the upper layer. Multiple temperature and salinity fronts, spaced 60-70 km apart andsuggestive oi baroclinic Rossby waves, are observed off northeastern Japan at the confluence ol the Kurosniowith the Oyashio. Not all temperature and salinity fronts are accompanied by strong baroclinic flow and themaximum baroclinic flow often occurs several kilometers distant f...
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The Hilbert transform of a real-valued time-domain signal x(t) is another real-valued time-domain signal, denoted by x(t), such that z(t) = x(t) + jx(t) is an analytic signal. Like Fourier transforms, Hilbert transforms are linear operators. This chapter presents three equivalent mathematical definitions for the Hilbert transform, followed by examples and basic properties. The intrinsic nature of the Hilbert transform to causal functions and physically realizable systems is also shown. The chapter derives special formulas for the Hilbert transform of correlation functions and their envelopes. It outlines applications for both nondispersive and dispersive propagation. The computation of two envelope signals is discussed, and this is followed by correlation of the envelope signals. The Hilbert transform for general records can be defined in three ways namely, definition as convolution integrals, definition as phase shift system, and definition as imaginary part of analytic signal.
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Every manager must assess and prioritize anthropogenic impacts on their management area from a long list of threats, but data which allow comparison of the relative ecological impacts of threats for decision‐making is often unavailable. This study employed a systematic and standardized method to collect and quantitatively synthesize expert opinion on the ecological effects of anthropogenic threats to the world's largest marine protected area: the Papahānaumokuākea Marine National Monument (MNM) in the Northwestern Hawaiian Islands (NWHI). In contrast to most threat ranking exercises, the method provides detail on the reasons behind a particular ranking of threats to an area and why the ranking may vary across the ecological landscape. Survey results from 25 experts allowed the comparison of the vulnerability of eight NWHI ecozones to 24 anthropogenic threats in a quantitative manner. Ecozones tended to have distinct top threats: sea‐level rise was identified as the top threat to rocky intertidal, beach and terrestrial ecozones; sea temperature rise was the top threat to the coral reef ecozones; bottom fishing was the top threat to the deep reef/bank ecozone; and pelagic fishing in the wider Pacific was the top threat to the pelagic ecozone owing to impacts on bird, turtle and fish fauna that forage outside the Papahānaumokuākea MNM boundaries. Many of these top threats are difficult for local managers to control because they arise from activities outside the Papahānaumokuākea MNM boundaries, indicating that additional work is needed to preserve the NWHI despite its highly protected status. The analysis indicates where inter‐agency cooperation in removing and mitigating threats should be focused. Copyright © 2008 John Wiley & Sons, Ltd.
Article
Marine debris (marine litter) is one of the most pervasive and solvable pollution problems plaguing the world’s oceans and waterways. Nets, food wrappers, cigarette filters, bottles, resin pellets, and other debris items can have serious impacts on wildlife, habitat, and human safety. Successful management of the problem requires a comprehensive understanding of both marine debris and human behavior. Knowledge is key for consumers to make appropriate choices when it comes to using and disposing of waste items. Education and outreach programs, strong laws and policies, and governmental and private enforcement are the building blocks for a successful marine pollution prevention initiative. The plastic industry also has a role to play in educating its employees and customers, and searching for technological mitigation strategies.
Article
Global set of trajectories of satellite-tracked Lagrangian drifters is used to study the dynamics of marine debris. A probabilistic model is developed to eliminate the bias in spatial distribution of drifter data due to heterogeneous deployments. Model experiments, simulating long-term evolution of initially homogeneous drifter array, reveal five main sites of drifter aggregation, located in the subtropics and maintained by converging Ekman currents. The paper characterizes the geography and structure of the collection regions and discusses factors that determine their dynamics. A new scale R(c)=(4k/|D|)(½) is introduced to characterize tracer distribution under competing effects of horizontal divergence D and diffusion k. Existence and locations of all five accumulation zones have been recently confirmed by direct measurements of microplastic at the sea surface.
Article
Oil spills are a major contributor to marine pollution. The objective of this work is to simulate the oil spill trajectory of oil released from a pipeline leaking in the Gulf of Mexico with the GNOME (General NOAA Operational Modeling Environment) model. The model was developed by NOAA (National Oceanic and Atmospheric Administration) to investigate the effects of different pollutants and environmental conditions on trajectory results. Also, a Texture-Classifying Neural Network Algorithm (TCNNA) was used to delineate ocean oil slicks from synthetic aperture radar (SAR) observations. During the simulation, ocean currents from NCOM (Navy Coastal Ocean Model) outputs and surface wind data measured by an NDBC (National Data Buoy Center) buoy are used to drive the GNOME model. The results show good agreement between the simulated trajectory of the oil spill and synchronous observations from the European ENVISAT ASAR (Advanced Synthetic Aperture Radar) and the Japanese ALOS (Advanced Land Observing Satellite) PALSAR (Phased Array L-band Synthetic Aperture Radar) images. Based on experience with past marine oil spills, about 63.0% of the oil will float and 18.5% of the oil will evaporate and disperse. In addition, the effects from uncertainty of ocean currents and the diffusion coefficient on the trajectory results are also studied.
Article
Whatever its origin is, a floating particle at the sea surface is advected by ocean currents. Surface currents could be derived from in situ observations or combined with satellite data. For a better resolution in time and space, we use satellite-derived sea-surface height and wind stress fields with a 1/3 degrees grid from 1993 to 2001 to determine the surface circulation of the South Pacific Ocean. Surface currents are then used to compute the Lagrangian trajectories of floating debris. Results show an accumulation of the debris in the eastern-centre region of the South Pacific subtropical gyre ([120 degrees W; 80 degrees W]-[20 degrees S; 40 degrees S]), resulting from a three-step process: in the first two years, mostly forced by Ekman drift, the debris drift towards the tropical convergence zone ( approximately 30 degrees S). Then they are advected eastward mostly forced by geostrophic currents. They finally reach the eastern-centre region of the South Pacific subtropical gyre from where they could not escape.
Article
Marine debris threatens Northwestern Hawaiian Islands' (NWHI) coral reef ecosystems. Debris, a contaminant, entangles and kills endangered Hawaiian monk seals (Monachus schauinslandi), coral, and other wildlife. We describe a novel multi-agency effort using divers to systematically survey and remove derelict fishing gear from two NWHI in 1999. 14 t of derelict fishing gear were removed and debris distribution, density, type and fouling level documented at Lisianski Island and Pearl and Hermes Atoll. Reef debris density ranged from 3.4 to 62.2 items/km2. Trawl netting was the most frequent debris type encountered (88%) and represented the greatest debris component recovered by weight (35%), followed by monofilament gillnet (34%), and maritime line (23%). Most debris recovered, 72%, had light or no fouling, suggesting debris may have short oceanic circulation histories. Our study demonstrates that derelict fishing gear poses a persistent threat to the coral reef ecosystems of the Hawaiian Archipelago.
Article
Large amounts of marine debris are present in shallow reefs adjacent to beach haulouts of the critically endangered Hawaiian monk seal, Monachus schauinslandi. These areas serve as seal pup nurseries, and injury and death caused by entanglement in marine debris are undermining population recovery efforts. We investigated the extent of this threat by measuring the accumulation of potentially entangling derelict fishing gear in nursery zones, 1999-2001. Plots of reef 1.0-1.3 km2 at three Northwestern Hawaiian Islands were initially cleaned of derelict fishing gear in 1999 then resurveyed in 2000 and 2001. Submerged debris densities across sites ranged from 16 to 165 debris items/km2. Resurveyed sites yielded annual marine debris accumulation rates from 0 to 141 debris items/km2. This large range was attributed to the physiography of reef areas surveyed. Trawl net webbing was significantly more common than other types of debris recovered and represented 84% of all debris encountered, suggesting that much of the debris originated from distant North Pacific Ocean fisheries. The likely source of most debris is the multinational trawl fisheries of the North Pacific Ocean. An international solution to this problem is needed. Targeted marine debris removal is a short-term, successful, entanglement mitigation strategy.
Article
Large amounts of derelict fishing gear accumulate and cause damage to shallow coral reefs of the Northwestern Hawaiian Islands (NWHI). To facilitate maintenance of reefs cleaned during 1996-2005 removal efforts, we identify likely high-density debris areas by assessing reef characteristics (depth, benthic habitat type, and energy regime) that influence sub-regional debris accumulation. Previously cleaned backreef and lagoonal reefs at two NWHI locations were resurveyed for accumulated debris using two survey methods. Accumulated debris densities and weights were found to be greater in lagoonal reef areas. Sample weight-based debris densities are extrapolated to similar habitats throughout the NWHI using a spatial 'net habitat' dataset created by generalizing IKONOS satellite derivatives for depth and habitat classification. Prediction accuracy for this dataset is tested using historical debris point data. Annual NWHI debris accumulation is estimated to be 52.0 metric tonnes. For planning purposes, individual NWHI atolls/reefs are allotted a proportion of this total.
Article
Data on the amount and type of small debris items deposited on the beaches of the Hawaiian Islands National Wildlife Refuge Tern Island station, French Frigate Shoals were collected over 16 years. We calculated deposition rates and investigated the relationship among deposition and year, season, El Niño and La Niña events from 1990 to 2006. In total 52,442 debris items were collected with plastic comprising 71% of all items collected. Annual debris deposition varied significantly (range 1116-5195 items) but was not influenced by season. Debris deposition was significantly greater during El Niño events as compared to La Niña events. Although often deduced to influence floating marine pollution, this study provides the first quantitative evidence of the influence of El Niño/La Niña cycles on marine debris deposition.
  • C Ribic
  • A Sheavly
  • S B Rugg
  • D J Erdmann
Ribic, C., A, Sheavly, S.B., Rugg, D.J., Erdmann, E.S., 2012. Trends in marine debris along the U.S. Pacific coast and Hawaii 1998–2007. Mar. Pollut. Bull. 64, 994–1004.
  • E Agustin
E. Agustin et al. / Marine Pollution Bulletin 101 (2015) 200–207
Tracking the sources and sinks of local marine debris in hawai'i
  • H Carson
  • M Lamson
  • D Nakashima
  • D Toloumu
  • J Hafner
  • N Maximenko
  • K Mcdermid
Carson, H., Lamson, M., Nakashima, D., Toloumu, D., Hafner, J., Maximenko, N., McDermid, K., 2013. Tracking the sources and sinks of local marine debris in hawai'i. Mar. Environ. Res. 84, 76-83.
Distribution and density of floating objects in the north Pacific based on 1987 sighting survey
  • Mio
Mio, S.i., Takehama, S., 1988. Distribution and density of floating objects in the north Pacific based on 1987 sighting survey. Proceedings of the 35th INPEC. Fisheries Agency of Japan.
Scud: surface currents from diagnostic model
  • Maximenko
Maximenko, N.A., Hafner, J., 2010. Scud: surface currents from diagnostic model. IPRC Tech. Note 5.
SAR observation and model tracking of an oil spill event in coastal waters
  • Y Cheng
  • X Li
  • Q Xu
  • O Garcia-Pineda
  • O Anderson
  • W Pichel
Cheng, Y., Li, X., Xu, Q., Garcia-Pineda, O., Anderson, O., Pichel, W., 2011. SAR observation and model tracking of an oil spill event in coastal waters. Mar. Pollut. Bull. 62, 350-363.
Tracking the sources and sinks of local marine debris in hawai'i
  • Carson
Global sea level observing system (gloss) implementation plan -2012
IOC, 2012. Global sea level observing system (gloss) implementation plan -2012. OC Technical Series No. 100.