A5080026650- Arctic and Antarctic ice dynamics
- Methane Hydrates and Related Phenomena
- Marine and coastal ecosystems
- Oceanographic and Atmospheric Processes
- Climate change and permafrost
- Geological Studies and Exploration
- Atmospheric and Environmental Gas Dynamics
- Ocean Acidification Effects and Responses
- Microbial Community Ecology and Physiology
- Radioactive contamination and transfer
- Food Industry and Aquatic Biology
- Marine and environmental studies
- Cryospheric studies and observations
- Marine Biology and Ecology Research
- Isotope Analysis in Ecology
- Arctic and Russian Policy Studies
- Atmospheric chemistry and aerosols
- Radioactive element chemistry and processing
- Climate variability and models
- Marine Bivalve and Aquaculture Studies
- Geology and Paleoclimatology Research
- Marine and fisheries research
- Maritime Navigation and Safety
- Indigenous Studies and Ecology
- Climate Change and Environmental Impact
Japan Agency for Marine-Earth Science and Technology
2016-2025
J-Power (Japan)
2017
Chubu Electric Power (Japan)
2012-2017
Panasonic (Japan)
2005
The spatial pattern of recent ice reduction in the Arctic Ocean is similar to distribution warm Pacific Summer Water (PSW) that interflows upper portion halocline southern Canada Basin. Increases PSW temperature basin are also well‐correlated with onset sea‐ice began late 1990s. However, increases do not correlate upstream source water northeastern Bering Sea, suggesting there another mechanism which controls these concurrent changes cover and ocean temperature. We propose a feedback whereby...
Acidic Ocean One consequence of the historically unprecedented level CO 2 in atmosphere that fossil fuel burning has caused, addition to a warmer climate, is higher concentrations dissolved oceans. This makes oceans more acidic, and thus less saturated with respect calcium carbonate. important ramifications for organisms have carbonate skeletons, which depend their survival on saturation state waters where they live. Yamamoto-Kawai et al. (p. 1098 ) report 2008, surface Canada Basin became...
Abstract Hydrographic data collected from research cruises, bottom‐anchored moorings, drifting Ice‐Tethered Profilers, and satellite altimetry in the Beaufort Gyre region of Arctic Ocean document an increase more than 6,400 km 3 liquid freshwater content 2003 to 2018: a 40% growth relative climatology 1970s. This fresh water accumulation is shown result persistent anticyclonic atmospheric wind forcing (1997–2018) accompanied by sea ice melt, wind‐forced redirection Mackenzie River discharge...
The extent of summer Arctic sea ice has reduced dramatically in recent years and, simultaneously, we have observed surface freshening over the Canada Basin 2006 and 2007. In order to identify source this fresh water, either meteoric or meltwater, salinity, δ 18 O, alkalinity were analyzed. Results show that meltwater increased water central part basin 2007, corresponding melting an additional 2.7 m (1.3 a −1 ) ice. Anomalously southern however, was mostly attributed Mackenzie River extending...
The contribution of freshwater components (e.g., meteoric, sea ice, and Pacific water) in the Canada Basin is quantified using salinity, δ 18 O, nutrient data collected 2003 2004. penetration depth ice meltwater limited to upper 30 m, brine, rejected during formation, observed from 250 m depth. fraction meteoric water high 50 decreases with entering via Bering Strait main source below throughflow, which transports salinity 32.5 together supplied upstream Strait, contributes up 75% input...
Pacific Water flows northward through Bering Strait and penetrates the Arctic Ocean halocline throughout Canadian Basin sector of Arctic.In summer, Summer (PSW) is modified by surface buoyancy fluxes mixing as it crosses shallow Chukchi Sea before entering deep ocean.Measurements from Ice-Tethered Profilers, moorings, hydrographic surveys between 2003 2013 reveal spatial temporal variability in PSW component Central Canada with increasing trends integrated heat freshwater content, a...
Abstract Marine nitrogen fixation occurs not only in subtropical and tropical regions but also colder regions. However, the distribution of diazotrophs, rate, its contribution to cycle Arctic Ocean remain poorly understood. We examined diazotroph community structure activity shelf off‐shelf Chukchi Sea, western Ocean, during late summer 2015. The nitrate ammonium assimilation rates were determined simultaneously gain insights into role region. by Illumina sequencing was mainly composed...
The future conditions of Arctic sea ice and marine ecosystems are interest not only to climate scientists, but also economic governmental bodies. However, the lack widespread, year-long biogeochemical observations remains an obstacle understanding complicated variability biological pump. Here we show early winter maximum sinking biogenic flux in western Ocean illustrate importance shelf-break eddies pumping from wide shelves adjacent deep basins using a combination mooring three-dimensional...
We produced 204 monthly maps of the air–sea CO2 flux in Arctic north 60°N, including Ocean and its adjacent seas, from January 1997 to December 2013 by using a self-organizing map technique. The partial pressure (pCO2) surface water data were obtained shipboard underway measurements or calculated alkalinity total inorganic carbon samples. Subsequently, we investigated basin-wide distribution seasonal interannual variability fluxes. 17-year annual mean shows that all areas seas net sinks....
The recent influx of microplastics into the Arctic Ocean may increase environmental stress on western marine ecosystem, which is experiencing significant sea-ice loss due to global warming. Quantitative data in are very limited, and microplastic budget water column completely unknown. To fill gaps our knowledge microplastics, we observed surface concentrations (number particles per unit volume seawater) meso- using a neuston net, wind speeds wave heights Chukchi Sea, Bering Strait, Sea. From...
We examine the varieties and spatial distributions of Pacific Eastern Arctic origin halocline waters in Canada Basin using 2002–2003 hydrographic data. The structure is different from because it includes fresher Winter Waters that form a “cold halostad” which lies above lower waters. halostad Basin, however, not spatially uniform, depends on pathway history source water. Water entering through Bering Strait becomes salty due to sea ice formation this, turn, dependent occurrence distribution...
Barrow Canyon, in the northeast Chukchi Sea, is a major conduit for Pacific Water to enter interior Arctic basins. Assemblies of annual (September 2000 August 2008) temperature, salinity, and velocity data acquired from mooring array mouth Canyon high‐resolution hydrographic transects along 2002, 2010, 2011 have enabled direct computation volume, heat, freshwater fluxes. Annual mean volume transport through was 0.45 Sv, which consisted 0.44 Sv 0.01 Atlantic Water. represents 55% long‐term...
The Arctic Ocean has been experiencing rapid warming, which accelerates sea ice melt. Further, the increasing area and duration of ice-free conditions enhance ocean uptake CO2. We conducted two shipboard experiments in September 2015 2016 to examine effects temperature, CO2, salinity on phytoplankton dynamics better understand impacts environmental changes ecosystem. Two temperature (control: <3°C 5°C above control), CO2 levels ~300 μatm 300/450 control; i.e., 600/750 μatm), 29 27 2016, 1.4...
[1] Recent freshening of the Arctic Ocean due to melting sea ice and enhanced Ekman pumping has deepened nutricline over Canada Basin reduced nutrient concentrations in euphotic zone. Cold-core eddies frequently transport nutrient-rich shelf water Basin, but are much deeper than Because warm-core appear near surface or at a depth range shallower that cold-core eddies, they may play crucial role determining distributions zone hence affect primary production. During late summer/early fall...
Abstract. This study aims to improve understanding of carbon cycling in the Buor-Khaya Bay (BKB) and adjacent part Laptev Sea by studying inter-annual, seasonal, meso-scale variability related hydrological biogeochemical parameters water, as well factors controlling dioxide (CO2) emission. Here we present data sets obtained on summer cruises winter expeditions during 12 yr investigation. Based analysis, suggest that heterotrophic BKB area, input terrestrially borne organic (OC) varies...
Abstract Isoprene (C 5 H 8 ) and three volatile organic iodine compounds (VOIs: CH 3 I, C 2 ClI) in surface seawater were measured the western Arctic, Northwest Pacific, Indian, Southern Oceans during period 2008–2012. These are believed to play an important role marine atmospheric chemistry after their emission. The measurements performed with high time‐resolution (1–6 h intervals) using online equilibrator gas chromatography mass spectrometer. was most abundant high‐productivity...
The location and magnitude of oceanic iron sources remain uncertain owing to a scarcity data, particularly in the Arctic Ocean. formation cold, dense water subsurface layer western Ocean is key process lateral transport iron, macronutrients, other chemical constituents. Here, we present humic-like fluorescent dissolved organic matter, nutrient concentration data waters above continental slope shelf along two transects across shelf-basin interface We detected high concentrations bottom plume...
Abstract. We analysed mooring and ship-based hydrographic biogeochemical data obtained from a Hope Valley biological hotspot in the southern Chukchi Sea. The moorings were deployed 16 July 2012 to 19 2014, captured during spring autumn blooms with high chlorophyll concentrations. Turbidity increased dissolved oxygen decreased bottom water at site before bloom, suggesting an accumulation of particulate organic matter its decomposition (nutrient regeneration) bottom. This event may have been...
Over the past few decades, sea ice retreat during summer has been enhanced in Pacific sector of Arctic basin, likely due part to increasing summertime heat flux Pacific-origin water from Bering Strait. Barrow Canyon, northeast Chukchi Sea, is a major conduit through which enters basin. This paper presents results 6 repeat high-resolution shipboard hydrographic/velocity sections occupied across Canyon 2010. The different masses feeding canyon – Alaskan coastal (ACW), Sea (BSW), and winter...
Abstract A fixed‐point observation station was set up in the northern Chukchi Sea during autumn 2013, and for about 2 weeks conductivity‐temperature‐depth (CTD)/water samplings (6 h) microstructure turbulence measurements (2 to 3 times a day) were performed. This enabled us estimate vertical nutrient fluxes impact of different types turbulent mixing on biological activity. There have been no such observations this region, where incoming low‐salinity water from Pacific Ocean, river water,...