Progress in Oceanography最新文献

{"title":"Eastern Tropical Pacific atmospheric and oceanic projected changes based on CMIP6 models","authors":"Rafael Ricardo Torres Parra ,&nbsp;David Francisco Bustos Usta ,&nbsp;Luis Jesús Otero Díaz ,&nbsp;María Paula Moreno-Ardila","doi":"10.1016/j.pocean.2024.103362","DOIUrl":"10.1016/j.pocean.2024.103362","url":null,"abstract":"<div><div>Atmosphere and ocean dynamics and their projections for the 21st century are assessed in the Eastern Tropical Pacific, using an ensemble of 17 models from the Coupled Model Intercomparison Project – CMIP6, under two radiative scenarios. Projections in the Panama Bight (PB) and Equatorial Pacific cold tongue (CT) are studied in more detail. In the 2071–2100 period and SSP5-8.5 scenario, referenced to the 1985–2014 period, air temperature (sea surface temperature) is expected to rise ∼3.5 °C (∼3 °C). Precipitation is projected to increase &gt; 3 mm day⁻¹ in the mean position of the Intertropical Convergence Zone, and decrease toward the north. A similar meridional pattern is projected in sea level atmospheric pressure and sea surface salinity (SSS) with negative anomalies toward the south. Large seasonal variations, which dominate the region, are projected to remain similar for the rest of the century. However, in January-April a weakening in the Panama wind jet and intensification of surface wind in the CT is expected, while in the June-November season, a weakening of the Choco wind jet will affect both sub-regions. Mean sea surface height (SSH) is expected to decrease, probably dominated by barotropic wind effects over SSS reduction effect on SSH. However, sterodynamic sea level (SDSL) is projected to rise (∼21 cm) driven by the global mean thermosteric contribution. For the end of the century, a mean sea level rise of ∼69 cm is estimated in the ETP, with SDSL being about half the barystatic contribution. These projections should be used with caution, as climate models have shown limitation reproducing atmospheric and ocean observations in the tropical Pacific Ocean during the last decades, due to large internal variability and systematic biases.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"229 ","pages":"Article 103362"},"PeriodicalIF":3.8,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A food-web assessment model for marine mammals, fish, and fisheries in the Norwegian and Barents Seas","authors":"Benjamin Planque ,&nbsp;Lucas Bas ,&nbsp;Martin Biuw ,&nbsp;Marie-Anne Blanchet ,&nbsp;Bjarte Bogstad ,&nbsp;Elena Eriksen ,&nbsp;Hilaire Drouineau ,&nbsp;Cecilie Hansen ,&nbsp;Bérengère Husson ,&nbsp;Erik Askov Mousing ,&nbsp;Christian Mullon ,&nbsp;Torstein Pedersen ,&nbsp;Morten D. Skogen ,&nbsp;Aril Slotte ,&nbsp;Arved Staby ,&nbsp;Ulf Lindstrøm","doi":"10.1016/j.pocean.2024.103361","DOIUrl":"10.1016/j.pocean.2024.103361","url":null,"abstract":"<div><div>The Norwegian and Barents Seas host large commercial fish populations that interact with each other, as well as marine mammal populations that feed on plankton and fish. Quantifying the past dynamics of these interacting species, and of the associated fisheries in the Norwegian and Barents Sea is of high relevance to support ecosystem-based management. The purpose of this work is to develop a food-web model of intermediate complexity and perform a quantitative assessment of the Norwegian and Barents Sea ecosystems in the period 1988–2021 in a manner that is consistent with existing data and expert knowledge, and that is internally coherent. For this purpose, we use the modelling framework of chance and necessity (CaN). The model construction follows an iterative process that allows to confront, discuss, and resolve multiple issues as well as to recognise uncertainties in expert knowledge, data, and input parameters. We show that it is possible to reconstruct the past dynamics of the food-web only if recognising that some data and assumptions are more uncertain than originally thought. According to this assessment, consumption by commercial fish and catch by fisheries jointly increased until the early 2010s, after which consumption by fish declined and catches by fisheries stabilised. On an annual basis, fish have consumed an average of 135.5 million tonnes of resources (including 9.5 million tonnes of fish), marine mammals have consumed an average of 22 million tonnes of which 50 % (11 million tonnes) were fish. Fisheries and hunting have captured an average of 4.4 million tonnes of fish and 7 thousand tonnes of marine mammals.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"229 ","pages":"Article 103361"},"PeriodicalIF":3.8,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extreme mismatch between phytoplankton and grazers during Arctic spring blooms and consequences for the pelagic food-web","authors":"Paul E. Renaud ,&nbsp;Malin Daase ,&nbsp;Eva Leu ,&nbsp;Maxime Geoffroy ,&nbsp;Sünnje Basedow ,&nbsp;Mark Inall ,&nbsp;Karley Campbell ,&nbsp;Emilia Trudnowska ,&nbsp;Einat Sandbank ,&nbsp;Frida Cnossen ,&nbsp;Muriel Dunn ,&nbsp;Lionel Camus ,&nbsp;Marie Porter ,&nbsp;Magnus Aune ,&nbsp;Rolf Gradinger","doi":"10.1016/j.pocean.2024.103365","DOIUrl":"10.1016/j.pocean.2024.103365","url":null,"abstract":"<div><div>Food-web structure determines the cycling pathways and fate of new production in marine ecosystems. Herbivorous zooplankton populations are usually seasonally coupled with pelagic primary producers. Synchrony of phytoplankton blooms with reproduction, recruitment and seasonal ascent of their main grazers ensures efficient transfer of organic carbon to higher trophic levels, including commercially harvested species, especially in high-latitude systems. Changes in light, nutrient, and sea-ice dynamics due to accelerating climate change in the Arctic, however, create large uncertainties in how these systems will function in the future. To address such knowledge gaps, we surveyed the pelagic ecosystem of the Barents Sea Polar Front in May of two consecutive years (2021 and 2022) to investigate the pelagic food-web from primary producers to planktivorous fish. In both years we observed unprecedentedly high phytoplankton chlorophyll <em>a</em> values in open as well as ice-covered waters, much of which was invisible to satellite remote sensing. We also measured very low densities of grazing zooplankton across a wide area and extending for at least one month. This extreme mismatch resulted in low feeding by capelin, and further suggests a high potential for vertical export of carbon to the benthos rather than efficient assimilation into the pelagic food web. As the Arctic continues to warm and is characterized by thinner and more mobile sea ice, we may expect higher variability in phytoplankton bloom phenology and more frequent mismatches with grazer life-histories. This could have significant impacts on ecosystem functioning by re-directing the flow of energy through the system towards seafloor rather than to the production of commercially valuable pelagic marine resources.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"229 ","pages":"Article 103365"},"PeriodicalIF":3.8,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142444685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatiotemporal changes in the community and demography of mesozooplankton in the eastern Indian sector of the Southern Ocean during austral summer 2018/2019","authors":"Kohei Matsuno ,&nbsp;Rikuto Sugioka ,&nbsp;Yurika Maeda ,&nbsp;Ryan Driscoll ,&nbsp;Fokje L. Schaafsma ,&nbsp;Sara Driscoll ,&nbsp;Atsushi Yamaguchi ,&nbsp;Ryuichi Matsukura ,&nbsp;Hiroko Sasaki ,&nbsp;Hiroto Murase","doi":"10.1016/j.pocean.2024.103360","DOIUrl":"10.1016/j.pocean.2024.103360","url":null,"abstract":"<div><div>The Southern Ocean is facing rapid environmental changes. However, few studies have been conducted on the spatiotemporal variability of mesozooplankton communities under recent climatic conditions, particularly in the eastern Indian sector. This study describes the spatiotemporal variability of the mesozooplankton community and the demographics of large copepods and krill in this sector, sampled through a Rectangular Mid-Water Trawl with 1 m² mouth area (RMT1) during the austral summer of 2018/2019 as part of the KY1804 survey. Cluster analysis indicated that the mesozooplankton community was divided into five groups that showed only small longitudinal differences, as they were affected by oceanic fronts. Part of the variability was explained by physical (local upwelling) and biological features (e.g., the occurrence of species showing a specific spatial distribution, such as <em>Euphausia crystallorophias</em>). Horizontal changes in the zooplankton community structure were not attributed to temporal changes during the 2-month sampling period. The demographics of the dominant species, <em>Calanoides acutus</em>, <em>Calanus propinquus</em>, <em>Metridia gerlacheri,</em> and <em>Thysanoessa macrura</em>, exhibited significant temporal differences in abundance or mean stage index (MSI) between the early and late seasons. These differences matched the growth rates estimated in previous studies, suggesting that their growth during the study period was constant without regional differences. There were no evident changes in the abundance or demographics of <em>Rhinalanus gigas</em>, suggesting that they were in their reproductive season. These species-specific demographics could be explained by the species life cycles: growth in <em>C. acutus</em> and <em>C. propinquus</em> and reproduction in <em>R. gigas</em> during the austral summer. Abundances and MSIs confirmed the growth of dominant copepods and krill during the sampling period; however, no evident seasonal changes were observed in the zooplankton community structure. The findings of this study contribute to the understanding of lower trophic levels in marine ecosystems and the present carbon cycle in the eastern Indian sector of the Southern Ocean.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"229 ","pages":"Article 103360"},"PeriodicalIF":3.8,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of the trophic sources and pathways of mesozooplankton and ichthyoplankton in the Kuroshio current and its neighboring waters","authors":"Toru Kobari ,&nbsp;Ayane Taniguchi ,&nbsp;Manami Hirata ,&nbsp;Gen Kume ,&nbsp;Mutsuo Ichinomiya ,&nbsp;Tomohiro Komorita ,&nbsp;Masafumi Kodama ,&nbsp;Fumihiro Makino ,&nbsp;Junya Hirai","doi":"10.1016/j.pocean.2024.103356","DOIUrl":"10.1016/j.pocean.2024.103356","url":null,"abstract":"<div><div>Commercially important fish spend their vulnerable early life stages in the Kuroshio Current, resulting in high fishery production even in the vicinity of poor prey availability under oligotrophic conditions. Nevertheless, little information is available on how ichthyoplankton are supported by trophodynamics in complicated food webs. Here, we have explored trophic sources and pathways toward ichthyoplankton in the Kuroshio and its neighboring waters based on metabarcoding analysis of gut DNA content for major taxonomic groups of mesozooplankton and ichthyoplankton. Calanoids were found to be the most predominant and frequently appearing prey, whereas non-crustaceans were the secondary prey for most mesozooplankton and ichthyoplankton groups. Trophic networks based on gut DNA content demonstrated that calanoids were the most important sector with multiple linkages among their prey and predators, and gelatinous and non-crustacean mesozooplankton were the secondary sectors. These findings suggest that calanoids are important hubs of trophic pathways toward ichthyoplankton, and that gelatinous and non-crustacean mesozooplankton groups strengthen trophic relationships with multiple components. Contrary to general thought, our metabarcoding analysis has revealed that trophodynamics toward ichthyoplankton are not strongly dependent on the grazing food chain, but are supported by multiple trophic pathways in the Kuroshio and its neighboring waters.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"229 ","pages":"Article 103356"},"PeriodicalIF":3.8,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Drivers of trophodynamics of the open-ocean and deep-sea environments of the Azores, NE Atlantic","authors":"Joana Brito ,&nbsp;Ambre Soszynski ,&nbsp;Johanna J. Heymans ,&nbsp;Simone Libralato ,&nbsp;Eva Giacomello ,&nbsp;Laurence Fauconnet ,&nbsp;Gui M. Menezes ,&nbsp;Telmo Morato","doi":"10.1016/j.pocean.2024.103357","DOIUrl":"10.1016/j.pocean.2024.103357","url":null,"abstract":"<div><div>Marine ecosystems associated with mid-oceanic elevations harbour unique pelagic and benthic biodiversity and sustain food webs critical for Nature’s contributions to people (NCP). The United Nations Sustainable Development Goals and the Convention on the Law of the Sea recognize the need to implement ecosystem-based management approaches to conserve the structure and functioning of oceanic and deep-sea ecosystems within sustainable reference points. However, uncertainties regarding the interactions between multiple drivers of change, and their impacts on the state of these ecosystems and the NCP, present significant challenges to effective management. Trophic models offer a holistic approach to identify the main drivers affecting the dynamics of marine ecosystems. Here, we used a food web model of the open-ocean and deep-sea environments of the Azores for identifying the drivers that best explain historical biomass trends of demersal fish of high commercial value. Our hindcast simulations suggested that historical trends can be explained by the combined effects of deep-sea fisheries exploitation and variability in environmental conditions, likely dominated by primary productivity anomalies. In particular, deficits in primary production and high levels of fishing exploitation might have contributed to the pronounced decline in biomass observed between 2008 and 2012. These findings reinforce that failure to consider environmental factors in ecosystem-based management may result in shortfalls at achieving biodiversity conservation and sustainability objectives, particularly in the context of climate change.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"229 ","pages":"Article 103357"},"PeriodicalIF":3.8,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142444686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics and dynamics of the interannual eddy kinetic energy variation in the Western Equatorial Pacific Ocean","authors":"Xueqi Liu ,&nbsp;Hui Zhou ,&nbsp;Hengchang Liu ,&nbsp;Wenlong Yang","doi":"10.1016/j.pocean.2024.103358","DOIUrl":"10.1016/j.pocean.2024.103358","url":null,"abstract":"<div><div>The interannual variations of eddy kinetic energy (EKE) in the western equatorial Pacific Ocean are investigated based on satellite observations and model outputs in this study. Results reveal that the EKE exhibits vigorous interannual variations, especially in the region of North Equatorial Countercurrent (NECC) and north of New Guinea, and the variations differ between the two types of El Niño events. The energy budget diagnosis indicates that the EKE variations are mainly attributed to the barotropic instability associated with the background currents. Specifically, the energetic NECC behaves northward shift and a stronger meander path, which favors the enhancement of EKE variations due to the enhanced barotropic instability. The interannual fluctuations of the strength of the New Guinea Coastal Current/Undercurrent (NGCC/NGCUC) and the eastward current along the equator contribute to the significant EKE interannual variations north of New Guinea. Further, the distinct features of EKE variations in two types of El Niño events are as follows: EKE typically weakens in the western equatorial Pacific during Eastern Pacific El Niño (EP-El Niño) events, whereas it intensifies north of New Guinea during Central Pacific El Niño (CP-El Niño) events. The opposite features north of New Guinea are attributed to the wind work and a stronger eastward current along the equator in CP-El Niño events. These results can contribute to a better understanding of the low-frequency eddy-mean flow interactions.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"229 ","pages":"Article 103358"},"PeriodicalIF":3.8,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Habitat shifts of the vulnerable crinoid Leptometra phalangium under climate change scenarios","authors":"Jade Millot ,&nbsp;Vincent Georges ,&nbsp;Valentina Lauria ,&nbsp;Tarek Hattab ,&nbsp;Carlos Dominguez-Carrió ,&nbsp;Vasilis Gerovasileiou ,&nbsp;Christopher J. Smith ,&nbsp;Chryssi Mytilineou ,&nbsp;M. Teresa Farriols ,&nbsp;Marie-Claire Fabri ,&nbsp;Pierluigi Carbonara ,&nbsp;Daniela Massi ,&nbsp;Paola Rinelli ,&nbsp;Adriana Profeta ,&nbsp;Giovanni Chimienti ,&nbsp;Angélique Jadaud ,&nbsp;Ioannis Thasitis ,&nbsp;Kelly Camilleri ,&nbsp;Jurgen Mifsud ,&nbsp;Sandrine Vaz","doi":"10.1016/j.pocean.2024.103355","DOIUrl":"10.1016/j.pocean.2024.103355","url":null,"abstract":"<div><div>Crinoid beds of <em>Leptometra phalangium</em> (Müller, 1841) have been identified as sensitive habitats by the General Fisheries Commission for the Mediterranean (GFCM) due to their high vulnerability to bottom trawl fisheries. Poorly resilient to physical damage, <em>L. phalangium</em> has been listed as a potential indicator of Vulnerable Marine Ecosystems (VMEs) in the Mediterranean Sea. If fishing activities represent the main cause of habitat destruction for this species, the ongoing changes in climate conditions may rapidly exacerbate the process. In this study, we developed an ensemble Species Distribution Modeling framework to predict the potential habitat of <em>L. phalangium</em> for present-days in the Mediterranean Sea, and used the model to infer potential changes in its spatial distribution by 2050 under two different climate scenarios (IPCC Representative Concentration Pathways RCP2.6 and RCP8.5). True presence-absence records were used and correlated to a parsimonious set of environmental predictors considered as important drivers of benthic species distribution. In present conditions, <em>L. phalangium</em> seems to be widely distributed along the continental slopes of the western and central Mediterranean. This crinoid is often described as confined to the continental shelf-break (100–200 m), but our results show that it can be found over a wider depth range, between 100 and 500 m. Our predictions obtained for the mid-21st century indicate an important habitat loss for <em>L. phalangium</em> under future climate conditions, mainly in the central and southern basins. Declines of 50 to 70 % in its suitable habitat were predicted under RCP2.6 and RCP8.5 compared to present-day predictions. Climate refugia (i.e., areas where environmental conditions remain suitable for the species in the future) were restricted to the northwestern basin (e.g., Gulf of Lion, the Catalan Sea, the Balearic Sea, Ligurian Sea) and in the southern Adriatic Sea. Provided by a robust statistical framework, climate refugia predictions, along with uncertainty assessments, must support the identification of priority areas for the conservation of VME indicator species by governmental bodies and regional management organizations.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"229 ","pages":"Article 103355"},"PeriodicalIF":3.8,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142326512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Altimeter-derived poleward Lagrangian pathways in the California Current System: Part 1","authors":"P. Ted Strub ,&nbsp;Corinne James ,&nbsp;Jennifer L. Fisher ,&nbsp;Melanie R. Fewings ,&nbsp;Samantha M. Zeman ,&nbsp;Vincent Combes ,&nbsp;Jessica C. Garwood ,&nbsp;Anna E. Bolm ,&nbsp;Andrew Scherer","doi":"10.1016/j.pocean.2024.103353","DOIUrl":"10.1016/j.pocean.2024.103353","url":null,"abstract":"<div><div>We use altimeter-derived geostrophic velocities, with and without the addition of surface Ekman transports, to create trajectories for virtual parcels in the California Current System (CCS). The goal is to investigate the poleward transport of passive water parcels in the surface 50–100 m of the nominally equatorward system. Motivation for the study is provided by observations of anomalous biomass of copepods with warm water affinities along the Newport Hydrographic Line off central Oregon (44.7°N) during El Niño years, as well as during and following the 2014–2016 marine heat wave. By backward tracking virtual parcels from 44.7°N, we find that the most distant source of passive water parcels in the upper ocean during a one-year period of travel is from within the Southern California Bight (SCB), north of 30°N. To make that journey, parcels use the Inshore Countercurrent off southern and central California during summer–winter and the Davidson Current off northern California and Oregon during autumn–winter. The inclusion of small-scale eddy diffusion usually increases the number of parcels that reach more northern latitudes, while the inclusion of Ekman velocities more often reduces those numbers. Even so, parcels can travel from the SCB to central Oregon in either the Ekman layer or beneath it in the geostrophic flow. Using backward tracking, we find that parcels arrive at 44.7°N most often in winter–spring, least often in autumn. They arrive from within the large-cape region off northern California (41°–42°N) during all years and all months, from just south of the large-cape region (38°–39°N) during most years but seldom in autumn, from south of Monterey Bay along central California (36°N) and within the SCB (34.5°N) during a third (or less) of the years and only in winter-spring. The shortest average transit times are found in winter: for parcels reaching 44.7°N in February, the average transit time is 2 months for parcels coming from 41°–42°N, 4 months for parcels coming from 38°–39°N, and 5–6 months or more for parcels coming from south of 36°N. Transit times increase as the arrival time progresses from winter to autumn. The longest average transit times are for parcels reaching central Oregon in autumn (9–12 months in October for parcels coming from south of 39°N). This makes the journey a multi-generational task for the copepods. Interannual variability in the observed southern copepod species biomass off central Oregon correlates highly with years when more virtual parcels from the south reach central and northern Oregon, providing increased confidence in the results found with the altimeter-derived parcel trajectories.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"229 ","pages":"Article 103353"},"PeriodicalIF":3.8,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142442944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of high-resolution regional ocean reanalysis K-ORA22 for the Northwest Pacific","authors":"Inseong Chang ,&nbsp;Young Ho Kim ,&nbsp;Young-Gyu Park ,&nbsp;Hyunkeun Jin ,&nbsp;Gyundo Pak ,&nbsp;Jae-Il Kwon ,&nbsp;You-Soon Chang","doi":"10.1016/j.pocean.2024.103359","DOIUrl":"10.1016/j.pocean.2024.103359","url":null,"abstract":"<div><div>The Korea Institute of Ocean Science and Technology developed the Korea Operational Oceanographic System-Ocean Predictability Experiment for Marine Environment (KOOS-OPEM), a high-resolution (1/24°, 51 vertical levels) ocean prediction model for the Northwest Pacific Ocean that incorporates ensemble optimal interpolation. In this study, we present KOOS-OPEM ReAnalysis version 2022 (K-ORA22), which covers the period from 2011 to 2022. We conducted a comparative analysis between K-ORA22 and other high-resolution (1/10°–1/12°) global reanalyses, including the Hybrid Coordinate Ocean Model, Global Ocean Reanalysis and Simulation (GLORYS), and Bluelink ReAnalysis (BRAN), to demonstrate the reproducibility and reliability of regional characteristics. Statistical comparisons revealed that while K-ORA22 exhibited some warm biases, its sea surface temperature (SST) anomaly correlation after removing the seasonal cycle was approximately 0.87, comparable to other reanalyses. Additionally, K-ORA22 effectively reproduced coastal upwelling, which is characterized by a sharp decrease in SST, as observed by marine meteorological buoys in the Southwest of the East/Japan Sea. K-ORA22 exhibits a warm bias of approximately 0.50 °C around 200 m, slightly higher than those of GLORYS and BRAN, while maintaining a low salinity bias in the subsurface. Notably, K-ORA22 outperformed the other reanalyses in accurately reproducing the unique characteristics of North Pacific and East Sea intermediate waters, characterized by a salinity minimum layer. In addition, K-ORA22 stands out in its ability to accurately reproduce the Yellow Sea Cold Water Mass with a low-temperature root-mean-square error (RMSE) of 0.76 °C in the Yellow Sea (YS) region. However, it exhibited the highest RMSE for salinity in the YS region and Korea/Tsushima Strait, indicating a potential overestimation of river discharge from Korea and China. While the sea surface height (SSH) anomaly correlation of K-ORA22 did not surpass 0.80 in the entire region because of limitations in the background error covariance used, its ability to reproduce the Kuroshio path was comparable to those of other reanalysis datasets. In conclusion, K-ORA22 excels in reproducing the unique characteristics of Korean marginal seas. Still, it exhibits weaknesses, such as the overestimation of river discharge and a somewhat limited ability to simulate SSH variability, compared with other global reanalyses. We plan to enhance K-ORA22 by updating background error covariance, addressing biases related to river discharge and assimilating the best available <em>in situ</em> observations and satellite data.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"229 ","pages":"Article 103359"},"PeriodicalIF":3.8,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142418165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}