A5086156400- Marine and coastal ecosystems
- Oceanographic and Atmospheric Processes
- Ocean Acidification Effects and Responses
- Methane Hydrates and Related Phenomena
- Atmospheric and Environmental Gas Dynamics
- Marine Biology and Ecology Research
- Marine and fisheries research
- Geology and Paleoclimatology Research
- Climate variability and models
- Coral and Marine Ecosystems Studies
- Isotope Analysis in Ecology
- Microbial Community Ecology and Physiology
- Marine Bivalve and Aquaculture Studies
- Marine and coastal plant biology
- Higher Education Learning Practices
- Arctic and Antarctic ice dynamics
- Geochemistry and Elemental Analysis
- Groundwater and Isotope Geochemistry
- Fish Ecology and Management Studies
- Problem and Project Based Learning
- earthquake and tectonic studies
- Atmospheric chemistry and aerosols
- Food Industry and Aquatic Biology
- Educational Robotics and Engineering
- Aquatic Ecosystems and Phytoplankton Dynamics
Hokkaido University
2015-2024
Environmental Earth Sciences
2011-2020
Japan Agency for Marine-Earth Science and Technology
2006-2017
Nagoya University
2013-2014
Japan Science and Technology Agency
2008-2013
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung
2012
Institute for Global Environmental Strategies
2002-2008
Sapporo University
2008
National Cerebral and Cardiovascular Center
2007
United States Global Change Research Program
2002
Abstract. Error-quantified, synoptic-scale relationships between chlorophyll-a (Chl-a) and phytoplankton pigment groups at the sea surface are presented. A total of ten were considered to represent three Phytoplankton Size Classes (PSCs, micro-, nano- picoplankton) seven Functional Types (PFTs, i.e. diatoms, dinoflagellates, green algae, prymnesiophytes (haptophytes), pico-eukaryotes, prokaryotes Prochlorococcus sp.). The observed Chl-a PSCs/PFTs well-defined global scale show that a...
Abstract Hollowed, A. B., Barange, M., Beamish, R., Brander, K., Cochrane, Drinkwater, Foreman, Hare, J., Holt, Ito, S-I., Kim, S., King, Loeng, H., MacKenzie, Mueter, F., Okey, T., Peck, M. A., Radchenko, V., Rice, Schirripa, Yatsu, and Yamanaka, Y. 2013. Projected impacts of climate change on marine fish fisheries. – ICES Journal Marine Science, 70: 1023–1037. This paper reviews current literature the projected effects shellfish, their fisheries, fishery-dependent communities throughout...
New radiocarbon and chlorofluorocarbon‐11 data from the World Ocean Circulation Experiment are used to assess a suite of 19 ocean carbon cycle models. We use distributions inventories these tracers as quantitative metrics model skill find that only about quarter is consistent with new data‐based metrics. This should serve warning bell larger community not all well current generation At same time, this highlights danger in simply using available models represent state‐of‐the‐art modeling...
A suite of standard ocean hydrographic and circulation metrics are applied to the equilibrium physical solutions from 13 global carbon models participating in phase 2 Ocean Carbon‐cycle Model Intercomparison Project (OCMIP‐2). Model‐data comparisons presented for sea surface temperature salinity, seasonal mixed layer depth, meridional heat freshwater transport, 3‐D fields, overturning. Considerable variation exists among OCMIP‐2 simulations, with some falling noticeably outside available...
Results are presented of export production, dissolved organic matter (DOM) and oxygen simulated by 12 global ocean models participating in the second phase Ocean Carbon‐cycle Model Intercomparison Project. A common, simple biogeochemical model is utilized different coarse‐resolution circulation models. The mean (±1 σ ) downward flux across 75 m depth 17 ± 6 Pg C yr −1 . means globally averaged particle export, fraction total form, surface semilabile carbon (DOC), seasonal net outgassing...
Distributions of chemical tracers in the world ocean are well reproduced an general circulation model which includes biogeochemical processes (biogeochemical model, B‐GCM). The difference concentration between surface and deep water depends not only on export production but also remineralization depth. Case studies changing vertical profile particulate organic matter (POM) flux show that phosphate distribution can be when POM observed by sediment traps is used. consistent with estimated to...
Nitrous oxide (N 2 O) is an important atmospheric greenhouse gas and involved in stratospheric ozone depletion. Analysis of the isotopomer ratios N O (i.e., intramolecular distribution 15 within linear NNO molecule conventional isotope ratios) can elucidate mechanisms production destruction. We analyzed dissolved at a site eastern tropical North Pacific (ETNP) Gulf California (GOC). At these sites, flux to atmosphere extremely high but denitrification activity oxygen minimum zone (OMZ) also...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 384:1-12 (2009) - DOI: https://doi.org/10.3354/meps08022 FEATURE ARTICLE Optimal uptake kinetics: physiological acclimation explains pattern of nitrate by phytoplankton in ocean S. Lan Smith1,*, Yasuhiro Yamanaka1,2,3, Markus Pahlow4, Andreas Oschlies4 1Ecosystem Change Research Program, Frontier Center for...
Significance Global degradation of coral reefs and macroalgal beds can have ecosystem-wide implications for biodiversity, ecological functioning, ocean resources. However, recent studies in warm temperate zones documented community shifts from macroalgae to corals, signaling a potential mechanism conservation under climate warming. Here, we present evidence that warming, aided by the dominant poleward-flowing current system, is facilitating expansion tropical corals herbivorous fishes into...
Abstract. We compare modeled oceanic carbon uptake in response to pulse CO2 emissions using a suite of global ocean models and Earth system models. In emission 590 Pg C (corresponding an instantaneous doubling atmospheric from 278 556 ppm), the fraction emitted that is absorbed by is: 37±8%, 56±10%, 81±4% (model mean ±2σ ) year 30, 100, 1000 after pulse, respectively. Modeled on timescales decades about century strongly correlated with simulated present-day chlorofluorocarbons (CFCs) across...
Abstract Yatsu, A., Chiba, S., Yamanaka, Y., Ito, S-I., Shimizu, Kaeriyama, M., and Watanabe, Y. 2013. Climate forcing the Kuroshio/Oyashio ecosystem. – ICES Journal of Marine Science, 70: 922–933. The Kuroshio Oyashio, western boundary currents in North Pacific, greatly influence climate, ecosystems, fisheries Pacific its adjacent waters. ecosystem (KOE) shows interannual decadal variability including regime shifts. Under a collaboration Forcing Ecosystem Response (CFAME) Task Team Working...
Dynamic Green Ocean Models (DGOMs) include different sets of Plankton Functional Types (PFTs) and equations, thus interactions food webs. Using four DGOMs (CCSM-BEC, PISCES, NEMURO PlankTOM5) we explore how predator–prey influence web dynamics. each model's equations biomass output, interaction strengths (direct specific) were calculated the role zooplankton in modeled webs examined. In CCSM-BEC single size-class adaptive preys on phytoplankton groups according to prey availability...
Abstract. We investigated the mechanisms of phytoplankton competition during spring bloom, one most dramatic seasonal events in lower-trophic-level ecosystems, four state-of-the-art plankton functional type (PFT) models: PISCES, NEMURO, PlankTOM5 and CCSM-BEC. In particular, we relative importance different ecophysiological processes on determination community structure, focusing both bottom-up top-down controls. The models reasonably reproduced observed global distribution variation...
Abstract Global warming is expected to decrease ocean oxygen concentrations by less solubility of surface and change in circulation. The associated expansion the minimum zone would have adverse impacts on marine organisms biogeochemical cycles. Oxygen reduction persist for a thousand years or more, even after atmospheric carbon dioxide stops rising. However, long‐term changes circulation are still unclear. Here we simulate multimillennium under doubling quadrupling dioxide, using fully...
Abstract After the occurrence of 2011 magnitude 9 Tohoku earthquake, seismicity in overriding plate changed. The appears to form distinct belts. From spatiotemporal distribution hypocenters, we can quantify evolution after earthquake. In some earthquake swarms near Sendai (Nagamachi‐Rifu fault), Moriyoshi‐zan volcano, Senya fault, and Yamagata–Fukushima border (Aizu‐Kitakata area, west Azuma volcano), observe temporal expansion focal area. This is attributed fluid diffusion. Observed...
<strong class="journal-contentHeaderColor">Abstract.</strong> Using results from four coupled global carbon cycle-climate models combined with in situ observations, we estimate the effects of future warming and ocean acidification on potential habitats for tropical/subtropical temperate coral communities seas around Japan. The suitability is classified basis currently observed regional ranges temperature saturation states regard to aragonite (Ω<sub>arag</sub>). We find that, under...
Abstract. The largest pH decline and widespread undersaturation with respect to aragonite in this century due uptake of anthropogenic carbon dioxide the Arctic Ocean have been projected. reductions saturation state caused by melting sea ice as well an increase concentration atmospheric dioxide. Therefore, future projections will be affected how rapidly reduction occurs. observed recent sea-ice loss has more rapid than projected many climate models that contributed Intergovernmental Panel on...
Nature-based tourism (NBT) practitioners urgently need to develop more and better quality products through including the findings of other scientific researchers. However, in many cases, NBT enterprises do not have enough resources invest building a sustainable relationship with such This paper reports on long-term involvement university researchers value co-creation – producing new tourist experiences jointly practitioners, encouraging significant innovative outcomes. It articulates how...
Abstract Subsurface chlorophyll maxima are widely observed in the ocean, and they often occur at greater depths than maximum phytoplankton biomass. However, a consistent mechanistic explanation for their distribution global ocean remains lacking. One possible mechanism is photoacclimation, whereby adjust cellular content response to environmental conditions. Here, we incorporate optimality-based photoacclimation theory based on resource allocation trade-off between nutrient uptake light...