cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.17592/001.2021102101
title: Antarctic shallow ice cores (NDF, NDFN, DFSE, DFNW) data: Density, chronology, permittivity, DEP, 0 - 20 m

description: The limited number of surface mass balance (SMB) observations in the Antarctic inland hampers estimates of ice sheet contribution to global sea level and locations with million year-old ice. We present finely resolved SMB over the past three centuries in a low-accumulation region on Dome Fuji derived from 1100 km of microwave radar stratigraphy dated with a firn core to 20 m depth where depth hoar dominates. The regional-mean SMB over the past 264 years is estimated to 22.5+-3.3 kg m-2a-1, but with large local variability of up to 30%. We found that local SMB is negatively correlated with surface slope at scales of a few hundred meters, resulting in anomalous zones of low SMB which represent as much as 8-10% of the total SMB on the inland plateau if the SMB-slope relationship is more widely valid. This impact should be investigated further to improve estimates of Antarctic mass balance and sea level contribution. This dataset contains the data from four shallow cores.
DOI: 10.17592/001.2021081701
title: Settling particle fluxes and hydrographic sensor data at Stations NAPt and CAPt, 2010-2014

description: This dataset contains total mass flux of settling particles, the bulk component, stable isotopes (delta13C, delta15N), and diatom assemblages of settling particles, and some daily hydrographic and sea ice conditions at Stations NAP10t-13t (74.5 to 75N, 161.9 to 162W) and CAP12t (75.2N 172.5W) in the western Arctic Ocean from October 2010 to September 2014 (Oct. 2012-Sep. 2013 for CAP12t). The analytical items of bulk component is particulate organic carbon, particulate inorganic carbon, particulate nitrogen, and biogenic opal. The component data for NAP10t includes additional results of elementary analysis on alminium, silicon, calcium, titanium, manganese, iron, magnesium and potassium. Water temerature and salinity were monitored at NAP13t and CAP12t. Current, turbidity, backscatterd acoustic strength, and ice thickness were observed at NAP13t. Reanalysed data on short wave radiation and sea ice concentration were also tabulated for the deployment perios of each sediemnt trap mooring.
DOI: 10.17592/001.2021082301
title: Surface heights over a traverse route from S16 to Dome Fuji, East Antarctica as measured by kinematic GNSS surveys in 2012-2013 and 2018-2019

description: Kinematic global navigation satellite system (GNSS) measurements provide in-situ data that are crucial for detecting subtle changes in the surface height of glaciers and ice sheets. Owing to their accuracy, which is typically less than half a meter, surface heights derived from kinematic GNSS surveys are both valuable and essential for evaluating changes in geometry of glaciers and for assessing satellite altimetry. Here, we present a surface height dataset derived from kinematic GNSS measurements covering a horizontal distance of approximately 1,200 km along an inland traverse route in East Antarctica from a coastal point near Syowa Station and Dome Fuji. More than 1,750,000 GNSS survey data points were processed and saved in CSV format. Based on our error analysis, the accuracy of the height data is less than 0.4 m in the horizontal and vertical directions. This dataset can be used to investigate surface height changes by comparing it with other datasets obtained in the past, as well as those from future remote sensing and in-situ observations.
DOI: 10.17592/001.2021102701
title: Composition of firn air at the H72 ice core site, Antarctica

description: Histories of atmospheric N2O concentration and its d15N and d18O were reconstructed on the basis of the analyses of firn air collected at the H72, Antarctica. The N2O concentration increased from 297 ppbv in 1975 to 314 ppbv in 1998, which reasonably agrees with the results from atmospheric observations and polar ice core analyses. The d15N and d18O showed a secular decrease, the respective values being 8.2 and 45.1% in 1975 and 7.1 and 44.6% in 2001. The secularly decreasing trends reflect that anthropogenic N2O emission from soils played a main role in the atmospheric N2O increase after industrialization.
DOI: 10.17592/001.2021093002
title: High-Resolution 10Be and 36Cl Data from the Antarctic Dome Fuji Ice Core (~100 years around 5480 BCE): An Unusual Grand Solar Minimum Occurrence?

description: Cosmogenic nuclides in tree rings and polar ice cores record the information of past cosmic ray intensities and solar activities. A large 14C increase over 10 years has been discovered around 5480 BCE. The 14C variations in this event differ from those of other short-term cosmic ray events and typical grand solar minima. To elucidate the cause of the 14C increase around 5480 BCE, we measured the 10Be and 36Cl concentrations in the Antarctic Dome Fuji ice core at quasi-annual and 4-5 year resolutions, respectively. Based on the combined 14C, 10Be, and 36Cl data, the 5480 BCE event was probably not caused by a solar proton event (SPE) or a gamma-ray event, because the 36Cl concentration did not significantly increase as expected in these events. The incremented 10Be data were enhanced similarly to those of recent grand solar minima, but more rapidly increased (over ~10 years). These results suggest that an unusual grand solar minimum occurred around 5480 BCE, characterized by a rapidly decreasing solar activity.
DOI: 10.17592/001.2021081001
title: Absolute gravity measurement data at Jang Bogo Station and Mario Zucchelli Station in 2019

description: The data set includes the absolute gravity measurement data that were acquired at Jang Bogo Station (JBS) and Mario Zucchelli Station (MZS), Terra Nova Bay, Antarctica, during the 2019-2020 austral summer season. A Micro-g LaCoste (MGL) FG5-210 absolute gravimeter was employed for the measurements, with the MGL g9 software used for both the data acquisition and processing. The JBS measurements were acquired at an existing gravity reference point, JBSAG1, and a newly established gravity reference point, JBSAG2. The MZS measurements were acquired at two existing gravity reference points, TNB AB and IAGS, where absolute gravity measurements have been repeatedly acquired. The precision of the measurements is better than 0.4 microGal (1 microGal = 10-8 m s-2), yielding an estimated accuracy of better than 5 microGal at each of the occupied gravity reference points. The provided data sets consist of the binary format files from the g9 software to fully ensure the ability to reprocess these data in the future. The data are also provided in three different text formats, thereby allowing these data to be readily used for a range of potential applications. A summary of the obtained absolute gravity values is provided as an Excel file, particularly for any users that are interested in the details of the absolute gravity values.
DOI: 10.17592/001.2021060901
title: Composition of firn air at the North Greenland Ice Core Project (NGRIP) site

description: Reconstructions of the past variations of atmospheric composition are important for better understanding of the changes of climate and atmospheric chemistry. While direct observations of atmospheric composition and isotope ratios are currently available, ice core analyses revealed those in the pre-industrial era. Porous compacted snow layers (firn) over ice sheets also archive air up to 100 years older than that at surface. Depth profiles from firn air measurements are therefore useful for reconstructing historical variations of trace gas species over times about century back in time. They are also helpful for improving firn air transport models toward better understanding of snow densification and interpretation of ice core data. Here we present depth profiles of air composition in the firn at a Greenland site of NGRIP (North Greenland Ice Core Project). Various greenhouse gases, halocarbons and isotope ratios were analyzed from air samples collected from the NGRIP firn by using combination of high-precision measurement systems.
DOI: 10.17592/001.2019122505
title: Biodiversity of multiple taxa and ecosystem properties in 2016

description: Ecosystem properties (surrogate index for ecosystem functioning) and species inventories for multiple taxa (Vascular plant, soil animal, and soil microbial) were measured in sub-arctic region along the Hudson Bay in Kuujjuarapik/Whapmagoostui, Quebec, Canada.
DOI: 10.17592/001.2021012601
title: Zooplankton monitoring using a twin NORPAC net during the 61st Japanese Antarctic Research Expedition in austral summer 2019-2020

description: As part of the monitoring program of the Japanese Antarctic Research Expedition (JARE), zooplankton sampling using a NORPAC (NORth PACific) standard net has been routinely carried out since JARE-14 (1972/73 season) to estimate the long-term trends of abundance, species composition and their temporal/spatial variation in the uppermost 150 m of the Indian Ocean sector of the Southern Ocean. Two separate monitoring surveys were completed during JARE-61 (December 2019 to March 2020). The icebreaker Shirase has a fixed schedule and route, traveling down longitude 110E each December and returning along 150E each March. Data collected on these fixed schedule seems to be ideal for long-term monitoring work in this region. We present data from its 2019/2020 voyage. In additions, separate samplings were carried out on board the T/V Umitaka-maru along 110E longitude in January 2020. This report provides the latest zooplankton data. These transect data can be used as time series and/or seasonal sets over the last 45 years.
DOI: 10.17592/002.2021030390
title: Near InfraRed Aurora and airglow Spectrograph (NIRAS) @ Syowa
title: Aurora and airglow spectroscopic observations

description: Nishiyama, T., Taguchi, M., Suzuki, H. et al. Temporal evolutions of N2+ Meinel (1,2) band near 1.5 um associated with aurora breakup and their effects on mesopause temperature estimations from OH Meinel (3,1) band. Earth Planets Space 73, 30 (2021). https://doi.org/10.1186/s40623-021-01360-0
DOI: 10.17592/001.2020101301
title: Physical and chemical oceanographic data during Umitaka-maru cruise of the 59th Japanese Antarctic Research Expedition in January 2018

description: Connecting all major ocean basins, the Southern Ocean is pivotal in the meridional overturning circulation of the global oceans. High quality physical and chemical oceanographic data in the Southern Ocean are thus critical for improved understanding of future climates. As a part of the 59th Japanese Antarctic Research Expedition research project, we have obtained high quality Conductivity Temperature Depth (CTD) and water sampling data (salinity, dissolved oxygen, and nutrients) at 6 sites located along 110 degree E transect, the southern end of which reached the sea ice edge. Sea surface temperature and salinity were continuously obtained with a Thermosalinograph (TSG) along cruise track taken between Ports of Fremantle and Hobart, except for Australian Exclusive Economic Zone. Data quality was validated by following as far as possible the recommendation for instruments and methods of Global Ocean Ship-Based Hydrographic Investigation Program. CTD and water sampling data are provided in Exchange formats for World Ocean Circulation Experiment Hydrographic Program CTD and bottle data; TSG data are in simple .csv format.
DOI: 10.17592/001.2020103001
title: Meteorological data from ice-free areas in Yukidori Zawa, Langhovde and Kizahashi Hama, Skarvsnes, and Skallen on Soya Coast, East Antarctica during January 2017 - December 2018

description: Meteorological data recorded by automatic weather stations (AWSs) in the Yukidori Zawa (Yukidori Valley), Langhovde, and in Kizahashi Hama, Skarvsnes on the Soya Coast of East Antarctica
DOI: 10.17592/001.2020091601
title: Arcitc-CORDEX dataset for Mirai observation in 2014

description: The Arctic Coordinated Regional Downscaling Experiment (Arctic CORDEX) is a part of the WCRP/CORDEX program. This project focused on the ice-free Arctic Ocean observed by the RV Mirai during September 2014. Each model center prepared the single grid model output at the closest grid point of the ship. This data set, which integrates the nine model runs with six different regional climate models, was analyzed in Inoue et al. (2020, submitted).
DOI: 10.17592/001.2020091501
title: Dataset associated with "Seasonal trends of atmospheric ice nucleating particles over Tokyo"

description: This repository includes the supplementary dataset for the paper entitled "Seasonal trends of atmospheric ice nucleating particles over Tokyo" by Y. Tobo et al. Note that the dataset for the 3-day mean number concentrations of atmospheric ice nucleating particles measured on Tokyo Skytree is archived in a different repository (https://ads.nipr.ac.jp/dataset/A20200727-004).
DOI: 10.17592/001.2020070704
title: Chlorophyll a and macro-nutrient concentrations and photosynthetically active radiation during the training vessel Umitaka-maru cruise of the 60th Japanese Antarctic Research Expedition in January 2019

description: Chlorophyll a concentration is the most common indicator of phytoplankton biomass, fundamentally regulated by macro-nutrients and light intensity. Therefore, long term monitoring of these parameters gives us basic information on ecosystem changes with climate changes. As part of the monitoring programs of the Japanese Antarctic Research Expedition (JARE), chlorophyll a concentration and macro-nutrients (nitrate, nitrite, phosphate and silicic acid) have been measured on board icebreakers Fuji and Shirase since JARE-14 (1972/73 season) and JARE-7 (1965/66 season), respectively. The same monitoring has also been conducted during the cruise of the training vessel (T/V) Umitaka-maru, Tokyo University of Marine Science and Technology since JARE-55 (2013/14 season). The course of the Umitaka-maru is almost same every year; leave from Fremantle, goes down to ice edge (ca. 65S) along 110E meridian and back to Hobart, covering sub-tropical to polar waters in the Southern Ocean. During the cruise, water sampling from underway pump for chlorophyll a and macro-nutrient concentrations were obtained twice a day, and photosynthetically active radiation was continuously measured by a sensor mounted on the navigation bridge deck of the ship. The vertical water sampling for chlorophyll a concentration was conducted at 6 station along 110E meridian, although concentration of macro-nutrients at the same stations were determined by the another monitoring program. This report is the latest data collected during the T/V Umitaka-maru cruise in 2018/19 season.
DOI: 10.17592/001.2020070703
title: Chlorophyll a and macro-nutrients concentrations during the ice breaker Shirase cruise of the 59th Japanese Antarctic Research Expedition

description: Chlorophyll a concentration is the most common indicator of phytoplankton biomass, basically regulated by macro-nutrients and light intensity. Therefore, long term monitoring of these parameters gives us fundamental information on ecosystem changes with climate changes. As part of the monitoring programs of the Japanese Antarctic Research Expedition (JARE), chlorophyll a concentration and macro-nutrients (nitrate, nitrite, phosphate and silicate) have been measured on board icebreakers Fuji and Shirase from JARE-14 in the 1972/73 season and from JARE-7 in the 1965/66 season, respectively. This report is the latest data determined during the Shirase cruise in 2017/18 season.
DOI: 10.17592/001.2020050101
title: Dome Fuji and NEEM ice cores, gas data (15N, 18O, O2/N2, Ar/N2, CH4, N2O, CO2, TAC)

description: Air in polar ice cores provides various information on past climatic and atmospheric changes. We developed a new method combining wet extraction, gas chromatography and mass spectrometry, for high-precision, simultaneous measurements of eight air components (CH4, N2O and CO2 concentrations, delta15N, delta18O, deltaO2/N2, deltaAr/N2 and total air content) from an ice core sample of ~60 g. The ice sample is evacuated for ~2 hours and melted under vacuum, and the released air is continuously transferred into a sample tube at 10 K within 10 minutes. The air is homogenized in the sample tube overnight, and split into two aliquots for mass spectrometric and gas chromatographic measurements. Cares are taken to minimize contamination of greenhouse gases with long evacuation time, consumption of oxygen during sample storage by passivation treatment on sample tubes, and fractionation of isotopic ratios with long homogenization time for splitting. Precisions are assessed by analysing standard gases with artificial ice, and by duplicate measurements of the Dome Fuji and NEEM ice cores. The overall reproducibility (one standard deviation) from duplicate ice-core analyses are 3.2 ppb, 2.2 ppb and 3.1 ppm for CH4, N2O and CO2 concentrations, 0.006, 0.010, 0.09 and 0.12 per mille for delta15N, delta18O, deltaO2/N2 and deltaAr/N2, and 0.67 mlSTP kg-1 for total air content, respectively. Our new method successfully combines the high-precision, small-sample and multiple-species measurements, with a wide range of applications for ice-core paleoenvironmental studies.
DOI: 10.17592/001.2020091101
title: Near-surface snow physics data from SIGMA-Traverse 2018

description: We performed a glaciological field traverse expedition with a traditional Greenlandic dog-sledge to obtain in-situ near-surface snow density and stratigraphy data in 2018 spring. This dataset includes these data from snow pits at four locations visited during the expedition. In addition, information on the spatial variability of snow density at the SIGMA-A site is provided. These data are in the easy-to-read excel format.
DOI: 10.17592/001.2020102701
title: Foraging behavior of Baikal seals.

description: 1. Foraging dives targetting amphipods by Baikal seals detected from accelerometer data. 2. No. of feeding events per dive and dive duration in pinnipeds and toothed whales (data for Fig. 4).
DOI: 10.17592/001.2020072701
title: Arctic river discharge and water temperature simulated by a land surface model, CHANGE

description: The land surface model, CHANGE, simulated Arctic river discharge and water temperature using three different gridded climatic datasets as inputs [WATCH Forcing-Data ERA-Interim; CRUNCEP - Atmospheric Forcing Data for the Community Land Model; and the Global Meteorological Forcing Dataset for land surface modelling from Princeton University]. The datasets are available for the 1979-2015 period, while the PRINC is from 1979-2012.
DOI: 10.17592/001.2020090101
title: Marine environments simulated by the pan-Arctic sea ice-ocean model

description: Monthly time series of sea-ice concentration (ai), sea-ice thickness (hi), sea surface temperature (sst), net shortwave radiation flux (swnt), net longwave radiation flux (lwnt), sensible heat flux (shfx), and latent heat flux (lhfx) for 1979-2018 simulated by the pan-Arctic sea ice-ocean model COCO4.9. All data are recorded in the GrADS format (4 byte binary without headers). Geographical information (e.g., seafloor topography, longitude, latitude, and grid size) is included in "topo.grd". The model domain covers the entire Arctic Ocean, the Nordic seas, and the North Atlantic north of 45 degree N. The model is configured in the spherical coordinate system rotated by 90 degree so that the singular points (i.e., the North and South Poles of the model grid) are located at the equator. The experimental design was developed at the Institute of Arctic Climate and Environment Research/Japan Agency for Marine-Earth Science and Technology (IACE/JAMSTEC). This work was supported by the Arctic Challenge for Sustainability (ArCS) project phase I-II.
DOI: 10.17592/001.2020070702
title: Chlorophyll a and macro-nutrient concentrations and photosynthetically active radiation during the training vessel Umitaka-maru cruise of the 59th Japanese Antarctic Research Expedition in January 2018

description: Chlorophyll a concentration is the most common indicator of phytoplankton biomass, fundamentally regulated by macro-nutrients and light intensity. Therefore, long term monitoring of these parameters gives us basic information on ecosystem changes with climate changes. As part of the monitoring programs of the Japanese Antarctic Research Expedition (JARE), chlorophyll a concentration and macro-nutrients (nitrate, nitrite, phosphate and silicic acid) have been measured on board icebreakers Fuji and Shirase since JARE-14 (1972/73 season) and JARE-7 (1965/66 season), respectively. The same monitoring has also been conducted during the cruise of the training vessel (T/V) Umitaka-maru, Tokyo University of Marine Science and Technology since JARE-55 (2013/14 season). The course of the Umitaka-maru is almost same every year; leave from Fremantle, goes down to ice edge (ca. 65S) along 110E meridian and back to Hobart, covering sub-tropical to polar waters in the Southern Ocean. During the cruise, water sampling from underway pump for chlorophyll a and macro-nutrient concentrations were obtained twice a day, and photosynthetically active radiation was continuously measured by a sensor mounted on the navigation bridge deck of the ship. The vertical water sampling for chlorophyll a concentration was conducted at 6 station along 110E meridian, although concentration of macro-nutrients at the same stations were determined by another monitoring program. This report is the latest data collected during the T/V Umitaka-maru cruise in 2017/18 season.
DOI: 10.17592/001.2020070701
title: Chlorophyll a and macro-nutrients concentrations during the ice breaker Shirase cruise of the 58th Japanese Antarctic Research Expedition

description: Chlorophyll a concentration is the most common indicator of phytoplankton biomass, basically regulated by macro-nutrients and light intensity. Therefore, long term monitoring of these parameters gives us fundamental information on ecosystem changes with climate changes. As part of the monitoring programs of the Japanese Antarctic Research Expedition (JARE), chlorophyll a concentration and macro-nutrients (nitrate, nitrite, phosphate and silicate) have been measured on board icebreakers Fuji and Shirase from JARE-14 in the 1972/73 season and from JARE-7 in the 1965/66 season, respectively. This report is the latest data determined during the Shirase cruise in 2016/17 season.
DOI: 10.17592/001.2019121101
title: Seasonal Variation of Wet Deposition of Black Carbon in Arctic Alaska

description: Black carbon (BC) aerosol deposited in and onto Arctic snow increases the snow's absorption of sunlight and accelerates snowmelt. Wet removal of BC from the atmosphere plays a key role in determining its abundance in the Arctic atmosphere and in Arctic snow. However, this process is poorly understood, mainly due to the scarcity of relevant measurements. To reveal characteristic features of the wet deposition of BC, we made measurements of mass concentration of BC in snow and rain (C_MBC) with relatively high (16%) accuracy and mass concentration of BC in air (M_BC) at the Barrow Atmospheric Baseline Observatory, Alaska, from July 2013 to August 2017 and analyzed them along with routinely measured meteorological parameters from Barrow. Monthly mean M_BC near the surface and C_MBC were poorly correlated from midwinter to early spring, when C_MBC was close to the annual median while M_BC was at its annual peak. Seasonal variations in the altitude distribution of M_BC may lead to these differences in seasonal variation of M_BC near the surface and C_MBC. About 50% of the annual wet deposition of BC occurred in the three months of summer, associated with high values of total precipitation and BC originating from biomass burning. Size distributions of BC in snow and rain were stable throughout the year, suggesting that the size distribution of BC in the lower troposphere was similarly stable. Calculations by two global models reproduced the observed seasonal variations of C_MBC and showed that BC from biomass burning dominated C_MBC in summer.