Articles | Volume 12, issue 23
https://doi.org/10.5194/bg-12-7107-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/bg-12-7107-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
08 Dec 2015
Research article |
| 08 Dec 2015
Ocean dynamic processes causing spatially heterogeneous distribution of sedimentary caesium-137 massively released from the Fukushima Daiichi Nuclear Power Plant
H. Higashi
CORRESPONDING AUTHOR
Center for Regional Environmental Research, National Institute for Environmental Studies, Tsukuba, Japan
Y. Morino
Center for Regional Environmental Research, National Institute for Environmental Studies, Tsukuba, Japan
N. Furuichi
Center for Regional Environmental Research, National Institute for Environmental Studies, Tsukuba, Japan
T. Ohara
Center for Regional Environmental Research, National Institute for Environmental Studies, Tsukuba, Japan
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Yange Deng, Satoshi Inomata, Kei Sato, Sathiyamurthi Ramasamy, Yu Morino, Shinichi Enami, and Hiroshi Tanimoto
Atmos. Chem. Phys., 21, 5983–6003, https://doi.org/10.5194/acp-21-5983-2021, https://doi.org/10.5194/acp-21-5983-2021, 2021
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The temperature and acidity dependence of yields and chemical compositions of the α-pinene ozonolysis SOA were systematically investigated using a newly developed compact chamber system. Increases in SOA yields were observed with the decrease in temperature and under acidic seed conditions. The differences in chemical compositions between acidic and neutral seed conditions were characterized and explained from the viewpoints of acid-catalyzed reactions. Some organosulfates were newly detected.
Junichi Kurokawa and Toshimasa Ohara
Atmos. Chem. Phys., 20, 12761–12793, https://doi.org/10.5194/acp-20-12761-2020, https://doi.org/10.5194/acp-20-12761-2020, 2020
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A long historical emission inventory of major air pollutants in Asia during 1950–2015 was developed as Regional Emission inventory in ASia version 3 (REASv3). Trends of emissions and changes in source contributions in countries and regions in Asia during these 6 decades were analyzed. REASv3 provides monthly gridded data with 0.25° by 0.25° resolution for major source categories as well as table of emissions by countries and sub-regions for major sectors and fuel types.
Daisuke Goto, Yu Morino, Toshimasa Ohara, Tsuyoshi Thomas Sekiyama, Junya Uchida, and Teruyuki Nakajima
Atmos. Chem. Phys., 20, 3589–3607, https://doi.org/10.5194/acp-20-3589-2020, https://doi.org/10.5194/acp-20-3589-2020, 2020
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To obtain reliable distribution of atmospheric Cs-137 emitted from the Fukushima accident, we proposed a multi-model ensemble (MME) method using observations. We found the MME-estimated Cs-137 concentrations using all available observations had lower bias, lower uncertainty, higher correlation and higher precision against the observations compared to single-model results. It can be applied not only to the Cs-137 distribution but also any atmospheric materials such as PM2.5 distribution.
Kei Sato, Yuji Fujitani, Satoshi Inomata, Yu Morino, Kiyoshi Tanabe, Toshihide Hikida, Akio Shimono, Akinori Takami, Akihiro Fushimi, Yoshinori Kondo, Takashi Imamura, Hiroshi Tanimoto, and Seiji Sugata
Atmos. Chem. Phys., 19, 14901–14915, https://doi.org/10.5194/acp-19-14901-2019, https://doi.org/10.5194/acp-19-14901-2019, 2019
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The volatility distributions of secondary organic aerosol (SOA) formed from the photooxidation of 1,3,5-trimethylbenzene were investigated by composition, heating, and dilution measurements. Fresh SOA, formed from 1,3,5-trimethylbenzene, included low-volatility compounds with < 1 μg m–3 saturation concentrations, which are not assumed to exist in fresh SOA particles in the standard volatility basis-set approach. Improvements in the organic aerosol model will be necessary.
Kei Sato, Yuji Fujitani, Satoshi Inomata, Yu Morino, Kiyoshi Tanabe, Sathiyamurthi Ramasamy, Toshihide Hikida, Akio Shimono, Akinori Takami, Akihiro Fushimi, Yoshinori Kondo, Takashi Imamura, Hiroshi Tanimoto, and Seiji Sugata
Atmos. Chem. Phys., 18, 5455–5466, https://doi.org/10.5194/acp-18-5455-2018, https://doi.org/10.5194/acp-18-5455-2018, 2018
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The volatility distribution of α-pinene secondary organic aerosols (SOAs) was evaluated with a wide range of techniques, including offline chemical analysis and dilution- and heat-induced evaporation. Compounds less volatile than semi-volatile products, i.e., highly oxygenated molecules and dimers, were identified as products, and the SOA evaporation with equilibration timescales of 24–46 min after dilution were observed.
Tatsuya Nagashima, Kengo Sudo, Hajime Akimoto, Junichi Kurokawa, and Toshimasa Ohara
Atmos. Chem. Phys., 17, 8231–8246, https://doi.org/10.5194/acp-17-8231-2017, https://doi.org/10.5194/acp-17-8231-2017, 2017
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We showed the large contribution of different source regions in Asia to the recent increasing trend in surface ozone over Japan by using a global chemical transport model. China accounted for the largest part of the increasing trend, not only through the domestic ozone production (36 %) but also the ozone production in the adjacent countries due to the ozone precursors emitted in China (10 %). Other factors such as temporal change in climate and methane concentration were also investigated.
Meng Li, Qiang Zhang, Jun-ichi Kurokawa, Jung-Hun Woo, Kebin He, Zifeng Lu, Toshimasa Ohara, Yu Song, David G. Streets, Gregory R. Carmichael, Yafang Cheng, Chaopeng Hong, Hong Huo, Xujia Jiang, Sicong Kang, Fei Liu, Hang Su, and Bo Zheng
Atmos. Chem. Phys., 17, 935–963, https://doi.org/10.5194/acp-17-935-2017, https://doi.org/10.5194/acp-17-935-2017, 2017
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An anthropogenic emission inventory for Asia is developed for the years 2008 and 2010 to support the Model Inter-Comparison Study for Asia (MICS-Asia) and the Task Force on Hemispheric Transport of Air Pollution (TF HTAP) projects by a mosaic of up-to-date regional emission inventories. The total Asian emissions in 2010 are estimated as follows: 51.3 Tg SO2, 52.1 Tg NOx, 336.5 Tg CO, 67.0 Tg NMVOC, 28.7 Tg NH3, 31.7 Tg PM10, 22.7 Tg PM2.5, 3.5 Tg BC, 8.3 Tg OC, and 17.3 Pg CO2.
D. Goto, T. Dai, M. Satoh, H. Tomita, J. Uchida, S. Misawa, T. Inoue, H. Tsuruta, K. Ueda, C. F. S. Ng, A. Takami, N. Sugimoto, A. Shimizu, T. Ohara, and T. Nakajima
Geosci. Model Dev., 8, 235–259, https://doi.org/10.5194/gmd-8-235-2015, https://doi.org/10.5194/gmd-8-235-2015, 2015
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An aerosol-coupled global non-hydrostatic model with a stretched-grid system has been developed to simulate aerosols on a region scale of 10 km grids. The regional simulation does require either a nesting technique or lateral boundary conditions, as opposed to general regional models. It generally reproduces monthly mean distributions of the observed sulfate and SO2 over East Asia as well as the diurnal and synoptic variations of the observed ones around the main target region, Tokyo/Japan.
S. Itahashi, I. Uno, H. Irie, J.-I. Kurokawa, and T. Ohara
Atmos. Chem. Phys., 14, 3623–3635, https://doi.org/10.5194/acp-14-3623-2014, https://doi.org/10.5194/acp-14-3623-2014, 2014
J. Kurokawa, T. Ohara, T. Morikawa, S. Hanayama, G. Janssens-Maenhout, T. Fukui, K. Kawashima, and H. Akimoto
Atmos. Chem. Phys., 13, 11019–11058, https://doi.org/10.5194/acp-13-11019-2013, https://doi.org/10.5194/acp-13-11019-2013, 2013
T. Stavrakou, J.-F. Müller, K. F. Boersma, R. J. van der A, J. Kurokawa, T. Ohara, and Q. Zhang
Atmos. Chem. Phys., 13, 9057–9082, https://doi.org/10.5194/acp-13-9057-2013, https://doi.org/10.5194/acp-13-9057-2013, 2013
H. Irie, K. Yamaji, K. Ikeda, I. Uno, S. Itahashi, T. Ohara, and J. Kurokawa
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-14037-2013, https://doi.org/10.5194/acpd-13-14037-2013, 2013
Preprint withdrawn
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Biogeosciences, 19, 5667–5687, https://doi.org/10.5194/bg-19-5667-2022, https://doi.org/10.5194/bg-19-5667-2022, 2022
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Lin Yang, Jing Zhang, Anja Engel, and Gui-Peng Yang
Biogeosciences, 19, 5251–5268, https://doi.org/10.5194/bg-19-5251-2022, https://doi.org/10.5194/bg-19-5251-2022, 2022
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Enrichment factors of dissolved organic matter (DOM) in the eastern marginal seas of China exhibited a significant spatio-temporal variation. Photochemical and enrichment processes co-regulated DOM enrichment in the sea-surface microlayer (SML). Autochthonous DOM was more frequently enriched in the SML than terrestrial DOM. DOM in the sub-surface water exhibited higher aromaticity than that in the SML.
Mona Norbisrath, Johannes Pätsch, Kirstin Dähnke, Tina Sanders, Gesa Schulz, Justus E. E. van Beusekom, and Helmuth Thomas
Biogeosciences, 19, 5151–5165, https://doi.org/10.5194/bg-19-5151-2022, https://doi.org/10.5194/bg-19-5151-2022, 2022
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Total alkalinity (TA) regulates the oceanic storage capacity of atmospheric CO2. TA is also metabolically generated in estuaries and influences coastal carbon storage through its inflows. We used water samples and identified the Hamburg port area as the one with highest TA generation. Of the overall riverine TA load, 14 % is generated within the estuary. Using a biogeochemical model, we estimated potential effects on the coastal carbon storage under possible anthropogenic and climate changes.
Kyle E. Hinson, Marjorie A. M. Friedrichs, Raymond G. Najjar, Maria Herrmann, Zihao Bian, Gopal Bhatt, Pierre St-Laurent, Hanqin Tian, and Gary Shenk
EGUsphere, https://doi.org/10.5194/egusphere-2022-1028, https://doi.org/10.5194/egusphere-2022-1028, 2022
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Climate impacts are essential for environmental managers to consider when implementing nutrient reduction plans designed to reduce hypoxia. This work highlights relative sources of uncertainty in modeling regional climate impacts on the Chesapeake Bay watershed and consequent declines in Bay oxygen levels. The results demonstrate that planned water quality improvement goals are capable of reducing hypoxia levels by half, offsetting climate-driven impacts to terrestrial runoff.
Le Zhang and Z. George Xue
Biogeosciences, 19, 4589–4618, https://doi.org/10.5194/bg-19-4589-2022, https://doi.org/10.5194/bg-19-4589-2022, 2022
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We adopt a high-resolution carbon model for the Gulf of Mexico (GoM) and calculate the decadal trends of important carbon system variables in the GoM from 2001 to 2019. The GoM surface CO2 values experienced a steady increase over the past 2 decades, and the ocean surface pH is declining. Although carbonate saturation rates remain supersaturated with aragonite, they show a slightly decreasing trend. The northern GoM is a stronger carbon sink than we thought.
Michael M. Whitney
Biogeosciences, 19, 4479–4497, https://doi.org/10.5194/bg-19-4479-2022, https://doi.org/10.5194/bg-19-4479-2022, 2022
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Coastal hypoxia is a major environmental problem of increasing severity. The 21st-century projections analyzed indicate global coastal waters will warm and experience rapid declines in oxygen. The forecasted median coastal trends for increasing sea surface temperature and decreasing oxygen capacity are 48 % and 18 % faster than the rates observed over the last 4 decades. Existing hypoxic areas are expected to worsen, and new hypoxic areas likely will emerge under these warming-related pressures.
Bryce Van Dam, Nele Lehmann, Mary A. Zeller, Andreas Neumann, Daniel Pröfrock, Marko Lipka, Helmuth Thomas, and Michael Ernst Böttcher
Biogeosciences, 19, 3775–3789, https://doi.org/10.5194/bg-19-3775-2022, https://doi.org/10.5194/bg-19-3775-2022, 2022
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We quantified sediment–water exchange at shallow sites in the North and Baltic seas. We found that porewater irrigation rates in the former were approximately twice as high as previously estimated, likely driven by relatively high bioirrigative activity. In contrast, we found small net fluxes of alkalinity, ranging from −35 µmol m−2 h−1 (uptake) to 53 µmol m−2 h−1 (release). We attribute this to low net denitrification, carbonate mineral (re-)precipitation, and sulfide (re-)oxidation.
Jiaying Abby Guo, Robert Strzepek, Anusuya Willis, Aaron Ferderer, and Lennart Thomas Bach
Biogeosciences, 19, 3683–3697, https://doi.org/10.5194/bg-19-3683-2022, https://doi.org/10.5194/bg-19-3683-2022, 2022
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Ocean alkalinity enhancement is a CO2 removal method with significant potential, but it can lead to a perturbation of the ocean with trace metals such as nickel. This study tested the effect of increasing nickel concentrations on phytoplankton growth and photosynthesis. We found that the response to nickel varied across the 11 phytoplankton species tested here, but the majority were rather insensitive. We note, however, that responses may be different under other experimental conditions.
Malcolm E. Scully, W. Rockwell Geyer, David Borkman, Tracy L. Pugh, Amy Costa, and Owen C. Nichols
Biogeosciences, 19, 3523–3536, https://doi.org/10.5194/bg-19-3523-2022, https://doi.org/10.5194/bg-19-3523-2022, 2022
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For two consecutive summers, the bottom waters in southern Cape Cod Bay became severely depleted of dissolved oxygen. Low oxygen levels in bottom waters have never been reported in this area before, and this unprecedented occurrence is likely the result of a new algae species that recently began blooming during the late-summer months. We present data suggesting that blooms of this new species are the result of regional climate change including warmer waters and changes in summer winds.
Zheng Chen, Bin Wang, Chuang Xu, Zhongren Zhang, Shiyu Li, and Jiatang Hu
Biogeosciences, 19, 3469–3490, https://doi.org/10.5194/bg-19-3469-2022, https://doi.org/10.5194/bg-19-3469-2022, 2022
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Deterioration of low-oxygen conditions in the coastal waters off Hong Kong was revealed by monitoring data over two decades. The declining wind forcing and the increasing nutrient input contributed significantly to the areal expansion and intense deterioration of low-oxygen conditions. Also, the exacerbated eutrophication drove a shift in the dominant source of organic matter from terrestrial inputs to in situ primary production, which has probably led to an earlier onset of hypoxia in summer.
Stella-Theresa Stoicescu, Jaan Laanemets, Taavi Liblik, Māris Skudra, Oliver Samlas, Inga Lips, and Urmas Lips
Biogeosciences, 19, 2903–2920, https://doi.org/10.5194/bg-19-2903-2022, https://doi.org/10.5194/bg-19-2903-2022, 2022
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Coastal basins with high input of nutrients often suffer from oxygen deficiency. In summer 2018, the extent of oxygen depletion was exceptional in the Gulf of Riga. We analyzed observational data and found that extensive oxygen deficiency appeared since the water layer close to the seabed, where oxygen is consumed, was separated from the surface layer. The problem worsens if similar conditions restricting vertical transport of oxygen occur more frequently in the future.
Justin C. Tiano, Jochen Depestele, Gert Van Hoey, João Fernandes, Pieter van Rijswijk, and Karline Soetaert
Biogeosciences, 19, 2583–2598, https://doi.org/10.5194/bg-19-2583-2022, https://doi.org/10.5194/bg-19-2583-2022, 2022
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This study gives an assessment of bottom trawling on physical, chemical, and biological characteristics in a location known for its strong currents and variable habitats. Although trawl gears only removed the top 1 cm of the seabed surface, impacts on reef-building tubeworms significantly decreased carbon and nutrient cycling. Lighter trawls slightly reduced the impact on fauna and nutrients. Tubeworms were strongly linked to biogeochemical and faunal aspects before but not after trawling.
Karl Michael Attard, Anna Lyssenko, and Iván Franco Rodil
Biogeosciences Discuss., https://doi.org/10.5194/bg-2022-119, https://doi.org/10.5194/bg-2022-119, 2022
Revised manuscript accepted for BG
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Aquatic plants produce a large amount of organic matter through photosynthesis that, following seasonal decay or storms, is deposited on the seafloor. In this study, we show that plant detritus can trigger low oxygen conditions (hypoxia) in shallow coastal waters, making conditions challenging for most marine animals. We propose that the occurrence of hypoxia may be underestimated because measurements typically do not consider the region closest to the seafloor, where detritus accumulates.
Inda Brinkmann, Christine Barras, Tom Jilbert, Tomas Næraa, K. Mareike Paul, Magali Schweizer, and Helena L. Filipsson
Biogeosciences, 19, 2523–2535, https://doi.org/10.5194/bg-19-2523-2022, https://doi.org/10.5194/bg-19-2523-2022, 2022
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The concentration of the trace metal barium (Ba) in coastal seawater is a function of continental input, such as riverine discharge. Our geochemical records of the severely hot and dry year 2018, and following wet year 2019, reveal that prolonged drought imprints with exceptionally low Ba concentrations in benthic foraminiferal calcium carbonates of coastal sediments. This highlights the potential of benthic Ba / Ca to trace past climate extremes and variability in coastal marine records.
Shichao Tian, Birgit Gaye, Jianhui Tang, Yongming Luo, Wenguo Li, Niko Lahajnar, Kirstin Dähnke, Tina Sanders, Tianqi Xiong, Weidong Zhai, and Kay-Christian Emeis
Biogeosciences, 19, 2397–2415, https://doi.org/10.5194/bg-19-2397-2022, https://doi.org/10.5194/bg-19-2397-2022, 2022
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We constrain the nitrogen budget and in particular the internal sources and sinks of nitrate in the Bohai Sea by using a mass-based and dual stable isotope approach based on δ15N and δ18O of nitrate. Based on available mass fluxes and isotope data an updated nitrogen budget is proposed. Compared to previous estimates, it is more complete and includes the impact of the interior cycle (nitrification) on the nitrate pool. The main external nitrogen sources are rivers contributing 19.2 %–25.6 %.
Gesa Schulz, Tina Sanders, Justus E. E. van Beusekom, Yoana G. Voynova, Andreas Schöl, and Kirstin Dähnke
Biogeosciences, 19, 2007–2024, https://doi.org/10.5194/bg-19-2007-2022, https://doi.org/10.5194/bg-19-2007-2022, 2022
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Estuaries can significantly alter nutrient loads before reaching coastal waters. Our study of the heavily managed Ems estuary (Northern Germany) reveals three zones of nitrogen turnover along the estuary with water-column denitrification in the most upstream hyper-turbid part, nitrate production in the middle reaches and mixing/nitrate uptake in the North Sea. Suspended particulate matter was the overarching control on nitrogen cycling in the hyper-turbid estuary.
Wiley Evans, Geoffrey T. Lebon, Christen D. Harrington, Yuichiro Takeshita, and Allison Bidlack
Biogeosciences, 19, 1277–1301, https://doi.org/10.5194/bg-19-1277-2022, https://doi.org/10.5194/bg-19-1277-2022, 2022
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Information on the marine carbon dioxide system along the northeast Pacific Inside Passage has been limited. To address this gap, we instrumented an Alaskan ferry in order to characterize the marine carbon dioxide system in this region. Data over a 2-year period were used to assess drivers of the observed variability, identify the timing of severe conditions, and assess the extent of contemporary ocean acidification as well as future levels consistent with a 1.5 °C warmer climate.
Melissa Ward, Tye L. Kindinger, Heidi K. Hirsh, Tessa M. Hill, Brittany M. Jellison, Sarah Lummis, Emily B. Rivest, George G. Waldbusser, Brian Gaylord, and Kristy J. Kroeker
Biogeosciences, 19, 689–699, https://doi.org/10.5194/bg-19-689-2022, https://doi.org/10.5194/bg-19-689-2022, 2022
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Here, we synthesize the results from 62 studies reporting in situ rates of seagrass metabolism to highlight spatial and temporal variability in oxygen fluxes and inform efforts to use seagrass to mitigate ocean acidification. Our analyses suggest seagrass meadows are generally autotrophic and variable in space and time, and the effects on seawater oxygen are relatively small in magnitude.
Tianfei Xue, Ivy Frenger, A. E. Friederike Prowe, Yonss Saranga José, and Andreas Oschlies
Biogeosciences, 19, 455–475, https://doi.org/10.5194/bg-19-455-2022, https://doi.org/10.5194/bg-19-455-2022, 2022
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The Peruvian system supports 10 % of the world's fishing yield. In the Peruvian system, wind and earth’s rotation bring cold, nutrient-rich water to the surface and allow phytoplankton to grow. But observations show that it grows worse at high upwelling. Using a model, we find that high upwelling happens when air mixes the water the most. Then phytoplankton is diluted and grows slowly due to low light and cool upwelled water. This study helps to estimate how it might change in a warming climate.
Shao-Min Chen, Ulf Riebesell, Kai G. Schulz, Elisabeth von der Esch, Eric P. Achterberg, and Lennart T. Bach
Biogeosciences, 19, 295–312, https://doi.org/10.5194/bg-19-295-2022, https://doi.org/10.5194/bg-19-295-2022, 2022
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Oxygen minimum zones in the ocean are characterized by enhanced carbon dioxide (CO2) levels and are being further acidified by increasing anthropogenic atmospheric CO2. Here we report CO2 system measurements in a mesocosm study offshore Peru during a rare coastal El Niño event to investigate how CO2 dynamics may respond to ongoing ocean deoxygenation. Our observations show that nitrogen limitation, productivity, and plankton community shift play an important role in driving the CO2 dynamics.
Paula Maria Salgado-Hernanz, Aurore Regaudie-de-Gioux, David Antoine, and Gotzon Basterretxea
Biogeosciences, 19, 47–69, https://doi.org/10.5194/bg-19-47-2022, https://doi.org/10.5194/bg-19-47-2022, 2022
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For the first time, this study presents the characteristics of primary production in coastal regions of the Mediterranean Sea based on satellite-borne observations for the period 2002–2016. The study concludes that there are significant spatial and temporal variations among different regions. Quantifying primary production is of special importance in the marine food web and in the sequestration of carbon dioxide from the atmosphere to the deep waters.
Samu Elovaara, Eeva Eronen-Rasimus, Eero Asmala, Tobias Tamelander, and Hermanni Kaartokallio
Biogeosciences, 18, 6589–6616, https://doi.org/10.5194/bg-18-6589-2021, https://doi.org/10.5194/bg-18-6589-2021, 2021
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Dissolved organic matter (DOM) is a significant carbon pool in the marine environment. The composition of the DOM pool, as well as its interaction with microbes, is complex, yet understanding it is important for understanding global carbon cycling. This study shows that two phytoplankton species have different effects on the composition of the DOM pool and, through the DOM they produce, on the ensuing microbial community. These communities in turn have different effects on DOM composition.
Yuan Dong, Qian P. Li, Zhengchao Wu, Yiping Shuai, Zijia Liu, Zaiming Ge, Weiwen Zhou, and Yinchao Chen
Biogeosciences, 18, 6423–6434, https://doi.org/10.5194/bg-18-6423-2021, https://doi.org/10.5194/bg-18-6423-2021, 2021
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Temporal change of plankton growth and grazing are less known in the coastal ocean, not to mention the relevant controlling mechanisms. Here, we performed monthly size-specific dilution experiments outside a eutrophic estuary over a 1-year cycle. Phytoplankton growth was correlated to nutrients and grazing mortality to total chlorophyll a. A selective grazing on small cells may be important for maintaining high abundance of large-chain-forming diatoms in this eutrophic system.
Kiefer O. Forsch, Lisa Hahn-Woernle, Robert M. Sherrell, Vincent J. Roccanova, Kaixuan Bu, David Burdige, Maria Vernet, and Katherine A. Barbeau
Biogeosciences, 18, 6349–6375, https://doi.org/10.5194/bg-18-6349-2021, https://doi.org/10.5194/bg-18-6349-2021, 2021
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We show that for an unperturbed cold western Antarctic Peninsula fjord, the seasonality of iron and manganese is linked to the dispersal of metal-rich meltwater sources. Geochemical measurements of trace metals in meltwaters, porewaters, and seawater, collected during two expeditions, showed a seasonal cycle of distinct sources. Finally, model results revealed that the dispersal of surface meltwater and meltwater plumes originating from under the glacier is sensitive to katabatic wind events.
Jenny Hieronymus, Kari Eilola, Malin Olofsson, Inga Hense, H. E. Markus Meier, and Elin Almroth-Rosell
Biogeosciences, 18, 6213–6227, https://doi.org/10.5194/bg-18-6213-2021, https://doi.org/10.5194/bg-18-6213-2021, 2021
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Dense blooms of cyanobacteria occur every summer in the Baltic Proper and can add to eutrophication by their ability to turn nitrogen gas into dissolved inorganic nitrogen. Being able to correctly estimate the size of this nitrogen fixation is important for management purposes. In this work, we find that the life cycle of cyanobacteria plays an important role in capturing the seasonality of the blooms as well as the size of nitrogen fixation in our ocean model.
Tom Hull, Naomi Greenwood, Antony Birchill, Alexander Beaton, Matthew Palmer, and Jan Kaiser
Biogeosciences, 18, 6167–6180, https://doi.org/10.5194/bg-18-6167-2021, https://doi.org/10.5194/bg-18-6167-2021, 2021
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The shallow shelf seas play a large role in the global cycling of CO2 and also support large fisheries. We use an autonomous underwater vehicle in the central North Sea to measure the rates of change in oxygen and nutrients.
Using these data we determine the amount of carbon dioxide taken out of the atmosphere by the sea and measure how productive the region is.
These observations will be useful for improving our predictive models and help us predict and adapt to a changing ocean.
Puthenveettil Narayana Menon Vinayachandran, Yukio Masumoto, Michael J. Roberts, Jenny A. Huggett, Issufo Halo, Abhisek Chatterjee, Prakash Amol, Garuda V. M. Gupta, Arvind Singh, Arnab Mukherjee, Satya Prakash, Lynnath E. Beckley, Eric Jorden Raes, and Raleigh Hood
Biogeosciences, 18, 5967–6029, https://doi.org/10.5194/bg-18-5967-2021, https://doi.org/10.5194/bg-18-5967-2021, 2021
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Upwelling in the coastal ocean triggers biological productivity and thus enhances fisheries. Therefore, understanding the phenomenon of upwelling and the underlying mechanisms is important. In this paper, the present understanding of the upwelling along the coastline of the Indian Ocean from the coast of Africa all the way up to the coast of Australia is reviewed. The review provides a synthesis of the physical processes associated with upwelling and its impact on the marine ecosystem.
Gaël Many, Caroline Ulses, Claude Estournel, and Patrick Marsaleix
Biogeosciences, 18, 5513–5538, https://doi.org/10.5194/bg-18-5513-2021, https://doi.org/10.5194/bg-18-5513-2021, 2021
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The Gulf of Lion shelf is one of the most productive areas in the Mediterranean. A model is used to study the mechanisms that drive the particulate organic carbon (POC). The model reproduces the annual cycle of primary production well. The shelf appears as an autotrophic ecosystem with a high production and as a source of POC for the adjacent basin. The increase in temperature induced by climate change could impact the trophic status of the shelf.
Alireza Merikhi, Peter Berg, and Markus Huettel
Biogeosciences, 18, 5381–5395, https://doi.org/10.5194/bg-18-5381-2021, https://doi.org/10.5194/bg-18-5381-2021, 2021
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The aquatic eddy covariance technique is a powerful method for measurements of solute fluxes across the sediment–water interface. Data measured by conventional eddy covariance instruments require a time shift correction that can result in substantial flux errors. We introduce a triple O2 sensor eddy covariance instrument that by design eliminates these errors. Deployments next to a conventional instrument in the Florida Keys demonstrate the improvements achieved through the new design.
Jiatang Hu, Zhongren Zhang, Bin Wang, and Jia Huang
Biogeosciences, 18, 5247–5264, https://doi.org/10.5194/bg-18-5247-2021, https://doi.org/10.5194/bg-18-5247-2021, 2021
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In situ observations over 42 years were used to explore the long-term changes to low-oxygen conditions in the Pearl River estuary. Apparent expansion of the low-oxygen conditions in summer was identified, primarily due to the combined effects of increased anthropogenic inputs and decreased sediment load. Large areas of severe low-oxygen events were also observed in early autumn and were formed by distinct mechanisms. The estuary seems to be growing into a seasonal, estuary-wide hypoxic zone.
Indah Ardiningsih, Kyyas Seyitmuhammedov, Sylvia G. Sander, Claudine H. Stirling, Gert-Jan Reichart, Kevin R. Arrigo, Loes J. A. Gerringa, and Rob Middag
Biogeosciences, 18, 4587–4601, https://doi.org/10.5194/bg-18-4587-2021, https://doi.org/10.5194/bg-18-4587-2021, 2021
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Organic Fe speciation is investigated along a natural gradient of the western Antarctic Peninsula from an ice-covered shelf to the open ocean. The two major fronts in the region affect the distribution of ligands. The excess ligands not bound to dissolved Fe (DFe) comprised up to 80 % of the total ligand concentrations, implying the potential to solubilize additional Fe input. The ligands on the shelf can increase the DFe residence time and fuel local primary production upon ice melt.
Melissa R. McCutcheon, Hongming Yao, Cory J. Staryk, and Xinping Hu
Biogeosciences, 18, 4571–4586, https://doi.org/10.5194/bg-18-4571-2021, https://doi.org/10.5194/bg-18-4571-2021, 2021
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We used 5+ years of discrete samples and 10 months of hourly sensor measurements to explore temporal variability and environmental controls on pH and pCO2 at the Aransas Ship Channel. Seasonal and diel variability were both present but small compared to other regions in the literature. Despite the small tidal range, tidal control often surpassed biological control. In comparison with sensor data, discrete samples were generally representative of mean annual and seasonal carbonate chemistry.
Kai G. Schulz, Eric P. Achterberg, Javier Arístegui, Lennart T. Bach, Isabel Baños, Tim Boxhammer, Dirk Erler, Maricarmen Igarza, Verena Kalter, Andrea Ludwig, Carolin Löscher, Jana Meyer, Judith Meyer, Fabrizio Minutolo, Elisabeth von der Esch, Bess B. Ward, and Ulf Riebesell
Biogeosciences, 18, 4305–4320, https://doi.org/10.5194/bg-18-4305-2021, https://doi.org/10.5194/bg-18-4305-2021, 2021
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Upwelling of nutrient-rich deep waters to the surface make eastern boundary upwelling systems hot spots of marine productivity. This leads to subsurface oxygen depletion and the transformation of bioavailable nitrogen into inert N2. Here we quantify nitrogen loss processes following a simulated deep water upwelling. Denitrification was the dominant process, and budget calculations suggest that a significant portion of nitrogen that could be exported to depth is already lost in the surface ocean.
Heiner Dietze and Ulrike Löptien
Biogeosciences, 18, 4243–4264, https://doi.org/10.5194/bg-18-4243-2021, https://doi.org/10.5194/bg-18-4243-2021, 2021
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In recent years fish-kill events caused by oxygen deficit have been reported in Eckernförde Bight (Baltic Sea). This study sets out to understand the processes causing respective oxygen deficits by combining high-resolution coupled ocean circulation biogeochemical modeling, monitoring data, and artificial intelligence.
Jens A. Hölemann, Bennet Juhls, Dorothea Bauch, Markus Janout, Boris P. Koch, and Birgit Heim
Biogeosciences, 18, 3637–3655, https://doi.org/10.5194/bg-18-3637-2021, https://doi.org/10.5194/bg-18-3637-2021, 2021
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The Arctic Ocean receives large amounts of river water rich in terrestrial dissolved organic matter (tDOM), which is an important component of the Arctic carbon cycle. Our analysis shows that mixing of three major freshwater sources is the main factor that regulates the distribution of tDOM concentrations in the Siberian shelf seas. In this context, the formation and melting of the land-fast ice in the Laptev Sea and the peak spring discharge of the Lena River are of particular importance.
Jaard Hauschildt, Soeren Thomsen, Vincent Echevin, Andreas Oschlies, Yonss Saranga José, Gerd Krahmann, Laura A. Bristow, and Gaute Lavik
Biogeosciences, 18, 3605–3629, https://doi.org/10.5194/bg-18-3605-2021, https://doi.org/10.5194/bg-18-3605-2021, 2021
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In this paper we quantify the subduction of upwelled nitrate due to physical processes on the order of several kilometers in the coastal upwelling off Peru and its effect on primary production. We also compare the prepresentation of these processes in a high-resolution simulation (~2.5 km) with a more coarsely resolved simulation (~12 km). To do this, we combine high-resolution shipboard observations of physical and biogeochemical parameters with a complex biogeochemical model configuration.
Samantha A. Siedlecki, Darren Pilcher, Evan M. Howard, Curtis Deutsch, Parker MacCready, Emily L. Norton, Hartmut Frenzel, Jan Newton, Richard A. Feely, Simone R. Alin, and Terrie Klinger
Biogeosciences, 18, 2871–2890, https://doi.org/10.5194/bg-18-2871-2021, https://doi.org/10.5194/bg-18-2871-2021, 2021
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Future ocean conditions can be simulated using projected trends in fossil fuel use paired with Earth system models. Global models generally do not include local processes important to coastal ecosystems. These coastal processes can alter the degree of change projected. Higher-resolution models that include local processes predict modified changes in carbon stressors when compared to changes projected by global models in the California Current System.
Erik Jacobs, Henry C. Bittig, Ulf Gräwe, Carolyn A. Graves, Michael Glockzin, Jens D. Müller, Bernd Schneider, and Gregor Rehder
Biogeosciences, 18, 2679–2709, https://doi.org/10.5194/bg-18-2679-2021, https://doi.org/10.5194/bg-18-2679-2021, 2021
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We use a unique data set of 8 years of continuous carbon dioxide (CO2) and methane (CH4) surface water measurements from a commercial ferry to study upwelling in the Baltic Sea. Its seasonality and regional and interannual variability are examined. Strong upwelling events drastically increase local surface CO2 and CH4 levels and are mostly detected in late summer after long periods of impaired mixing. We introduce an extrapolation method to estimate regional upwelling-induced trace gas fluxes.
Yangyang Zhao, Khanittha Uthaipan, Zhongming Lu, Yan Li, Jing Liu, Hongbin Liu, Jianping Gan, Feifei Meng, and Minhan Dai
Biogeosciences, 18, 2755–2775, https://doi.org/10.5194/bg-18-2755-2021, https://doi.org/10.5194/bg-18-2755-2021, 2021
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In situ oxygen consumption rates were estimated for the first time during destruction of coastal hypoxia as disturbed by a typhoon and its reinstatement in the South China Sea off the Pearl River estuary. The reinstatement of summer hypoxia was rapid with a comparable timescale with that of its initial disturbance from frequent tropical cyclones, which has important implications for better understanding the intermittent nature of coastal hypoxia and its prediction in a changing climate.
Dylan R. Brown, Humberto Marotta, Roberta B. Peixoto, Alex Enrich-Prast, Glenda C. Barroso, Mario L. G. Soares, Wilson Machado, Alexander Pérez, Joseph M. Smoak, Luciana M. Sanders, Stephen Conrad, James Z. Sippo, Isaac R. Santos, Damien T. Maher, and Christian J. Sanders
Biogeosciences, 18, 2527–2538, https://doi.org/10.5194/bg-18-2527-2021, https://doi.org/10.5194/bg-18-2527-2021, 2021
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Hypersaline tidal flats (HTFs) are coastal ecosystems with freshwater deficits often occurring in arid or semi-arid regions near mangrove supratidal zones with no major fluvial contributions. This study shows that HTFs are important carbon and nutrient sinks which may be significant given their extensive coverage. Our findings highlight a previously unquantified carbon as well as a nutrient sink and suggest that coastal HTF ecosystems could be included in the emerging blue carbon framework.
Giulia Bonino, Elisa Lovecchio, Nicolas Gruber, Matthias Münnich, Simona Masina, and Doroteaciro Iovino
Biogeosciences, 18, 2429–2448, https://doi.org/10.5194/bg-18-2429-2021, https://doi.org/10.5194/bg-18-2429-2021, 2021
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Seasonal variations of processes such as upwelling and biological production that happen along the northwestern African coast can modulate the temporal variability of the biological activity of the adjacent open North Atlantic hundreds of kilometers away from the coast thanks to the lateral transport of coastal organic carbon. This happens with a temporal delay, which is smaller than a season up to roughly 500 km from the coast due to the intense transport by small-scale filaments.
Markus Diesing, Terje Thorsnes, and Lilja Rún Bjarnadóttir
Biogeosciences, 18, 2139–2160, https://doi.org/10.5194/bg-18-2139-2021, https://doi.org/10.5194/bg-18-2139-2021, 2021
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The upper 10 cm of the seafloor of the North Sea and Skagerrak contain 231×106 t of carbon in organic form. The Norwegian Trough, the deepest sedimentary basin in the studied area, stands out as a zone of strong organic carbon accumulation with rates on par with neighbouring fjords. Conversely, large parts of the North Sea are characterised by rapid organic carbon degradation and negligible accumulation. This dual character is likely typical for continental shelf sediments worldwide.
Cited articles
Ambe, D., Kaeriyama, H., Shigenobu, Y., Fujimoto, K., Ono, T., Sawada, H., Saito, H., Miki, S., Setou, T., Morita, T., and Watanabe, T.: Five-minute resolved spatial distribution of radiocesium in sea sediment derived from the Fukushima Dai-ichi Nuclear Power Plant, J. Environ. Radioactiv., 138, 264–275, https://doi.org/10.1016/j.jenvrad.2014.09.007, 2014.
Aoyagi, K. and Igarashi, S.: On the size distribution of sediments in the coastal sea of Fukushima Prefecture, Bull. Fukushima Prefecture Fish. Exp. Station, 8, 69–81, 1999 (in Japanese).
Blaas, M., Dong, C., Marchesiello, P., McWilliams, J. C., and Stolzenbach, K. D.: Sediment-transport modeling on Southern Californian shelves: a ROMS case study, Cont. Shelf Res., 27, 832–853, 2007.
Buesseler, K., Aoyama, M., and Fukasawa, M.: Impacts of the Fukushima nuclear power plants on marine radioactivity, Environ. Sci. Technol., 45, 9931–9935, https://doi.org/10.1021/es202816c, 2011.
Buesseler, K. O., Jayne, S. R., Fisher, N. S., Rypina, I. I., Baumann, H., Baumann, Z., Breier, C. F., Douglass, E. M., George, J., Macdonald, A. M., Miyamoto, H., Nishikawa, J., Pike, S. M., and Yoshida, S.: Fukushima-derived radionuclides in the ocean and biota off Japan, P. Natl. Acad. Sci. USA, 109, 5984–5988, 2012.
Chino, M., Nakayama, H., Nagai, H., Terada, H., Katata, G., and Yamazawa, H.: Preliminary estimation of release amounts of 131I and 137Cs accidentally discharged from the Fukushima daiichi nuclear power plant into the atmosphere, J. Nucl. Sci. Technol., 48, 1129–1134, 2011.
Choi, Y., Kida, S., and Takahashi, K.: The impact of oceanic circulation and phase transfer on the dispersion of radionuclides released from the Fukushima Dai-ichi Nuclear Power Plant, Biogeosciences, 10, 4911–4925, https://doi.org/10.5194/bg-10-4911-2013, 2013.
Deltares: Delft3D-FLOW User Manual, Simulation of Multi-Dimensional Hydrodynamic Flows and Transport Phenomena, Including Sediments, Version: 3.15.25157, Deltares, the Netherlands, 674 pp., 2012.
Draxler, R. R.: The Use of global and mesoscale meteorological model data to predict the transport and dispersion of tracer plumes over Washington, D.C., Weather Forecast., 21, 383–394, https://doi.org/10.1175/WAF926.1, 2006.
Draxler, R., Arnold, D., Galmarini, S., Hort, M., Jones, A., Leadbetter, S., Malo, A., Maurer, C., Rolph, G., Saito, K., Servranckx, R., Shimbori, T., Solazzo, E., and Wotawa, G.: Evaluation of Meteorological Analyses For the Radionuclide Dispersion and Deposition From the Fukushima Daiichi Nuclear Power Plant Accident, WMO-No. 1120, World Meteorological Organization, Switzerland, 64 pp., available at: http://library.wmo.int/opac/index.php?lvl=notice_display&id=15838 (last access: 8 June 2015), 2013.
Flather, R. A.: A tidal model of the northwest European continental shelf, Memories de la Societe Royale des Sciences de Liege, 6, 141–164, 1976.
Fossing, H., Berg, P., Thamdrup, B., Rysgaard, S., Sørensen, H. M., and Nielsen, K.: A Model Set-Up For an Oxygen and Nutrient Flux Model For Aarhus Bay (Denmark), NERI Technical Report No. 483, National Environmental Research Institute, Denmark, 65 pp., 2004.
Furuichi, N. and Hibiya, T.: Assessment of the upper-ocean mixed layer parameterizations using a large eddy simulation model, J. Geophys. Res., 120, 2350–2369, https://doi.org/10.1002/2014JC010665, 2015.
Furuichi, N., Hibiya, T., and Niwa, Y.: Assessment of turbulence closure models for resonant inertial response in the oceanic mixed layer using a large eddy simulation model, J. Oceanogr., 68, 285–294, https://doi.org/10.1007/s10872-011-0095-3, 2012.
Higashi, H., Koshikawa, H., Murakami, S., and Kohata, K.: A long-term simulation study on variability of short-necked clam resources in Ise Bay in the 1990s, Journal of Japan Society of Civil Engineers, Ser. B2 (Coastal Engineering), 67, I_1046–I_1050, https://doi.org/10.2208/kaigan.67.I_1046, 2011 (in Japanese with English abstract).
Higashi, H., Furuichi, N., and Maki, H.: Validation of Vertical Mixing Schemes Based on In-situ Turbulence Measurements in Tokyo Bay, J. Jpn Soc. Civil Engineers, Ser. B2 (Coastal Engineering), 69, I_1066–I_1070, https://doi.org/10.2208/kaigan.69.I_1066, 2013 (in Japanese with English abstract).
Higashi, H., Morino Y., and Ohara, T.: A numerical study on oceanic dispersion and sedimentation of radioactive Cesium-137 from Fukushima Daiichi nuclear power plant, Journal of Japan Society of Civil Engineers, Ser. B2 (Coastal Engineering), 70, I_1121–I_1125, https://doi.org/10.2208/kaigan.70.I_1121, 2014 (in Japanese with English abstract).
Hirt, C. W. and Nichols, B. D.: Volume of fluid method for the dynamics of free boundaries, J. Comput. Phys., 39, 201–225, 1981.
Kawamura, H., Kobayashi, T., Furuno, A., In, T., Ishikawa, Y., Nakayama, T., Shima, S., and Awaji, T.: Preliminary numerical experiments on oceanic dispersion of 131I and 137Cs discharged into the ocean because of the Fukushima daiichi nuclear power plant disaster, J. Nucl. Sci. Technol., 48, 1349–1356, 2011.
Kobayashi, T., Otosaka, S., Togawa, O., and Hayashi, K.: Development of a non-conservative radionuclides dispersion model in the ocean and its application to surface cesium-137 dispersion in the Irish Sea, J. Nucl. Sci. Technol., 44, 238–247, https://doi.org/10.1080/18811248.2007.9711278, 2007.
Kobayashi, T., Nagai, H., Chino, M., and Kawamura, H.: Source term estimation of atmospheric release due to the Fukushima Daiichi Nuclear Power Plant accident by atmospheric and oceanic dispersion simulations, J. Nucl. Sci. Technol., 50, 255–264, https://doi.org/10.1080/00223131.2013.772449, 2013.
Kondo, J.: Air-sea bulk transfer coefficients in diabatic conditions, Bound.-Lay. Meteorol., 9, 91–112, 1975.
Kusakabe, M., Oikawa, S., Takata, H., and Misonoo, J.: Spatiotemporal distributions of Fukushima-derived radionuclides in nearby marine surface sediments, Biogeosciences, 10, 5019–5030, https://doi.org/10.5194/bg-10-5019-2013, 2013.
Lesser, G. R., Roelvink, J. A., van Kester, J. A. T. M., and Stelling, G. S.: Development and validation of a three-dimensional morphological model, Coast. Eng., 51, 883–915, 2004.
Matsumoto, K., Takanezawa, T., and Ooe, M.: Ocean tide models developed by assimilating TOPEX/POSEIDON altimeter data into hydrodynamical model: a global model and a regional model around Japan, J. Oceanogr., 56, 567–581, 2000.
Masumoto, Y., Miyazawa, Y., Tsumune, D., Kobayashi, T., Estournel, C., Marsaleix, P., Lanerolle, L., Mehra, A., and Garrao, Z. D.: Oceanic dispersion simulation of Cesium 137 from Fukushima Daiichi Nuclear Power Plant, Elements, 8, 207–212, 2012.
MEXT (Ministry of Education, Culture, Sports, Science and Technology): Monitoring Information of Environmental Radioactivity Level, available at: http://radioactivity.nsr.go.jp/en/ (last access: 8 June 2015), 2011.
MOE (Ministry of Environment): Radioactive Material Monitoring Surveys of the Water Environment, available at: http://www.env.go.jp/en/water/rmms/surveys.html (last access: 8 June 2015), 2011.
Misumi, K., Tsumune, D., Tsubono, T., Tateda, Y., Aoyama, M., Kobayashi, T., and Hirose, K.: Factors controlling the spatiotemporal variation of 137Cs in seabed sediment off the Fukushima coast: implications from numerical simulations, J. Environ. Radioactiv., 136, 218–228, https://doi.org/10.1016/j.jenvrad.2014.06.004, 2014.
Miyazawa, Y., Zhang, R., Guo, X., Tamura, H., Ambe, D., Lee, J. S., Okuno, A., Yoshinari, H., Setou, T., and Komatsu, K.: Water mass variability in the western North Pacific detected in a 15-year eddy resolving ocean reanalysis, J. Oceanogr., 65, 737–756, 2009.
Miyazawa, Y., Masumoto, Y., Varlamov, S. M., and Miyama, T.: Transport simulation of the radionuclide from the shelf to open ocean around Fukushima, Cont. Shelf Res., 50–51, 16–29, https://doi.org/10.1016/j.csr.2012.09.002, 2012.
Miyazawa, Y., Masumoto, Y., Varlamov, S. M., Miyama, T., Takigawa, M., Honda, M., and Saino, T.: Inverse estimation of source parameters of oceanic radioactivity dispersion models associated with the Fukushima accident, Biogeosciences, 10, 2349–2363, https://doi.org/10.5194/bg-10-2349-2013, 2013.
Monte, L., Periáñez, R., Boyer, P., Smith, J. T., and Brittain, J. E.: The role of physical processes controlling the behaviour of radionuclide contaminants in the aquatic environment: a review of state-of-the-art modelling approaches, J. Environ. Radioactiv., 100, 779–784, https://doi.org/10.1016/j.jenvrad.2008.05.006, 2009.
Morino, Y., Ohara, T., and Nishizawa, M.: Atmospheric behavior, deposition, and budget of radioactive materials from the Fukushima Daiichi nuclear power plant in March 2011, Geophys. Res. Lett., 38, L00G11, https://doi.org/10.1029/2011GL048689, 2011.
Murakami, K., Suganuma, F., and Sasaki, H.: Experimental Investigation on Erosion and Deposition of Fine Cohesive Sediments in an Annular Rotating Channel, Report of the Port and Harbour Research Institute, 28, Japan, 43–76, 1989.
Nakanishi, M. and Niino, H.: Development of an improved turbulence closure model for the atmospheric boundary layer, J. Meteorol. Soc. Jpn., 87, 895–912, 2009.
NRA (Nuclear Regulation Authority): Achievement Report on Measurement and Study of Radionuclide Distribution in Ocean in 2013 Japanese Fiscal Year, available at: http://radioactivity.nsr.go.jp/ja/contents/10000/9423/24/report_20140613.pdf (last access: 8 June 2015), 2014a (in Japanese).
Nuclear Regulation Authority (NRA): Monitoring Information of Environmental Radioactivity Level, available at: http://radioactivity.nsr.go.jp/en/ (last access: 8 June 2015), 2014b.
Otosaka, S. and Kato, Y.: Radiocesium derived from the Fukushima Daiichi Nuclear Power Plant accident in seabed sediments: initial deposition and inventories, Environ. Sci.: Proc. Impacts, 16, 978–990, https://doi.org/10.1039/c4em00016a, 2014.
Otosaka, S. and Kobayashi, T.: Sedimentation and remobilization of radiocesium in the coastal area of Ibaraki, 70 km south of the Fukushima Dai-ichi Nuclear Power Plant, Environ. Monit. Assess., 185, 5419–5433, https://doi.org/10.1007/s10661-012-2956-7, 2013.
Periáñez, R.: Redissolution and long-term transport of radionuclides released from a contaminated sediment: a numerical modelling study, Estuar. Coast. Shelf S., 56, 5–14, 2003a.
Periáñez, R.: Kinetic modelling of the dispersion of plutonium in the eastern Irish Sea: two approaches, J. Marine Syst., 38, 259–275, 2003b.
Periáñez, R.: Testing the behaviour of different kinetic models for uptake-release of radionuclides between water and sediments when implemented on a marine dispersion model, J. Environ. Radioactiv., 71, 243–259, 2004.
Periáñez, R.: A modelling study on 137Cs and 239,240Pu behaviour in the Alborán Sea, western Mediterranean, J. Environ. Radioactiv., 99, 694–715, 2008.
Periáñez, R., Suh, K. S., and Min, B. I.: Local scale marine modelling of Fukushima releases, Assessment of water and sediment contamination and sensitivity to water circulation description, Mar. Pollut. Bull., 64, 2333–2339, https://doi.org/10.1016/j.marpolbul.2012.08.030, 2012.
Reed, C. W., Niedoroda, A. W., and Swift, D. J. P.: Modeling sediment entrainment and transport processes limited by bed armoring, Mar. Geol., 154, 143–154, 1999.
Smagorinsky, J.: General circulation experiments with the primitive equations, I. The basic experiment, Mon. Weather Rev., 91, 99–164, 1963.
Sohma, A., Sekiguchi, Y., Kuwae, T., and Nakamura, Y.: A benthic-pelagic coupled ecosystem model to estimate the hypoxic estuary including tidal flat – model description and variation of seasonal/daily dynamics, Ecol. Model., 215, 10–39, https://doi.org/10.1016/j.ecolmodel.2008.02.027, 2008.
Sternberg, R. W., Berhane, I., and Ogston, A. S.: Measurement of size and settling velocity of suspended aggregates on the northern California continental shelf, Mar. Geol., 154, 43–53, 1999.
Stohl, A., Seibert, P., Wotawa, G., Arnold, D., Burkhart, J. F., Eckhardt, S., Tapia, C., Vargas, A., and Yasunari, T. J.: Xenon-133 and caesium-137 releases into the atmosphere from the Fukushima Dai-ichi nuclear power plant: determination of the source term, atmospheric dispersion, and deposition, Atmos. Chem. Phys., 12, 2313–2343, https://doi.org/10.5194/acp-12-2313-2012, 2012.
Terada, H., Katata, G., Chino, M., and Nagai, H.: Atmospheric discharge and dispersion of radionuclides during the Fukushima Dai-ichi Nuclear Power Plant accident. Part II: verification of the source term and analysis of regional-scale atmospheric dispersion, J. Environ. Radioactiv., 112, 141–154, 2012.
TEPCO (Tokyo Electric Power Corporation): Influence to Surrounding Environment, Archives, available at: www.tepco.co.jp/en/nu/fukushima-np/f1/index2-e.html (last access: 8 June 2015), 2011.
Thornton, B., Ohnishi, S., Ura, T., Odano, N., Sasaki, S., Fujita, T., Watanabe, T., Nakata, K., Ono, T., and Ambe, D.: Distribution of local 137Cs anomalies on the seafloor near the Fukushima Dai-ichi Nuclear Power Plant, Mar. Pollut. Bull., 74, 344–350, https://doi.org/10.1016/j.marpolbul.2013.06.031, 2013.
Tsumune, D., Tsubono, T., Aoyama, M., and Hirose, K.: Distribution of oceanic 137Cs from the Fukushima Dai-ichi Nuclear Power Plant simulated numerically by a regional ocean model, J. Environ. Radioactiv., 111, 100–108, 2012.
Tsumune, D., Tsubono, T., Aoyama, M., Uematsu, M., Misumi, K., Maeda, Y., Yoshida, Y., and Hayami, H.: One-year, regional-scale simulation of 137Cs radioactivity in the ocean following the Fukushima Dai-ichi Nuclear Power Plant accident, Biogeosciences, 10, 5601–5617, https://doi.org/10.5194/bg-10-5601-2013, 2013.
Ushijima, S., Takemura, M., and Nezu, I.: Investigation on computational schemes for MAC methods with collocated grid system, J. Jpn Soc. Civil Engineers, 719, 11–19, 2002 (in Japanese with English abstract).
Yasuda, I., Okuda, K., and Shimizu, Y.: Distribution and modification of the North Pacific Intermediate Water in the Kuroshio-Oyashio Interfrontal zone, J. Phys. Oceanogr., 26, 448–465, 1996.
Short summary
We elucidated ocean dynamic processes causing spatially-heterogeneous sedimentary radiocaesium-137 distribution in and around the shelf off Fukushima and adjacent prefectures on the basis of numerical simulation. Our result suggests that accumulation of sedimentary radiocaesium-137 in a swath just offshore of shelf break results from spatiotemporal variation of bottom friction occurred via a periodic spring tide about every 2 weeks and via occasional strong wind.
We elucidated ocean dynamic processes causing spatially-heterogeneous sedimentary...
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