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Study of long-term ionospheric variations based on Tromsø Ionosonde and EISCAT radar data
Get PDFThe 15th Symposium on Polar Science/Ordinary sessions [OS] Space and upper atmospheric sciences, Wed. 4 Dec. / Entrance Hall (1st floor), National Institute of Polar Researchconference outpu
New multi-wavelength all-sky imager systems for observation of polar cap aurora
Get PDFThe 15th Symposium on Polar Science/Ordinary sessions [OS] Space and upper atmospheric sciences, Wed. 4 Dec. / Entrance Hall (1st floor), National Institute of Polar Researchconference outpu
Origin of the nightside ionospheric convection for interplanetary magnetic field conditions of Bz>>|By|>0: An extremely modified Dungey cycle concurrent with the interchange cycle
Get PDFThe 15th Symposium on Polar Science/Ordinary sessions [OS] Space and upper atmospheric sciences, Wed. 4 Dec. / Entrance Hall (1st floor), National Institute of Polar Researchconference outpu
Investigation of background radiation levels and environmental radioactivity around Bharati Station, Larsemann Hills in east Antarctica-an overview
No full textStudy on the measurement of background radiation level in and around Bharati station, Larsemann Hills region of East Antarctica was taken up using different types of detectors. The radiation levels due to cosmogenic (especially neutron) and terrestrial origin (gamma and neutron) and natural radioactivity due to presence of primordial radionuclide in the samples of soil, rock, lake water, ice and air were measured. The data on radionuclide activities of soil and lake water are presented pictorially using surfer plot. The study was further extended to the in-situ measurement of Radon/Thoron concentration in soil pores. Measurement of gross alpha and beta activity in air samples was also carried out. These studies were conducted during several Indian Scientific Expeditions to Antarctica (ISEA) (32nd to 36th) for the period from 2012 to 2017. Some of the data generated during the above mentioned expeditions are already published previously and hence mentioned very briefly in the text whereas the unpublished data are presented and discussed in this article for the first time.journal articl
Interrelationships of CO2, CH4, and N2O fluxes in snow-covered temperate soils, Northern Japan
No full textThis study focuses on assessing the concentrations, fluxes, and production rates of greenhouse gases (CO2, CH4, and N2O) in a cold temperate grassland soil underlying snowpack during the winter of 1996/7 in northern Japan. Results included mean ± standard deviation (range) correlation coefficients (R2) for CO2–CH4 concentrations and CO2–N2O concentrations of 0.93 ± 0.07 (0.81–0.99) and 0.96 ± 0.06 (0.83–0.99) for winter, and 0.74 ± 0.17 (0.55–0.92) and 0.96 ± 0.05 (0.88–0.99) for summer, respectively. This suggests close relationships between the mechanisms of CO2 and N2O production and the oxidation of CH4, which are influenced by factors such as oxygen availability, temperature, and moisture in the soil. Furthermore, the study found that winter fluxes of CO2–CH4 and CO2–N2O through the snowpack showed positive linear correlations. Winter CO2 emissions accounted for 96 % of the variability in CH4 oxidation and 77 % of the variability in N2O emissions. This demonstrates that winter CO2 emissions were affected to the magnitude of CH4 oxidations and N2O emissions in the soil. These findings have implications for the modification of terrestrial ecosystem models in temperate regions, particularly in assessing contributions from winter greenhouse gas fluxes to overall annual emissions. Understanding the interrelationships and dynamics of greenhouse gases throughout the year is crucial for accurate modeling and predictions of ecosystem responses to climate change.journal articl
Characterizing Antarctic air-breathing predator dive patterns on a common prey base from stationary echosounders
No full textDiving patterns of air-breathing predators were monitored from three moored subsurface upward-looking echosounders. Complete and partial dive profiles were visible on active acoustic records as echoes that started and/or returned to the surface. Dive metrics: maximum dive depths, durations, and wiggle count were measured and angles, distances, and velocities, were calculated at each site. Dive shapes ‘U’, ‘V’ and ‘W’ were derived using the number of wiggles and the percentage of dive bottom time. Dive profiles were classified into four types with type 1 dives being short in total duration and distance, low velocities, small angles, shallow, and linked to ‘U’ and ‘W’ shapes. Type 2 dives were short in distance, had low velocities, shallow depths, and were linked to ‘V’ dives. Dive types 3 and 4 had higher velocities, larger angles, longer total durations, and were deeper than types 1 and 2. Observed dive types could correspond to travelling, exploring, and foraging predator behaviors. Significant predator-prey overlaps occurred with predator dive profile counts correlated with krill aggregation thickness, density, and depth. This study demonstrates the utility of using stationary active acoustics to identify predator dive profiles with a simultaneous characterization of the potential prey field.journal articl
Indigenous place names in arctic Canada: A publicly accessible inventory of projects
No full textToponyms contain Indigenous modes of understanding and reflect ecological histories and deep relationships between Indigenous communities, arctic environments, time, and land. Completed toponymic studies are useful for researchers to access; however, they are notoriously difficult to find. Many are completed by community groups and published on their websites, or are completed by government agencies and published as grey literature. An inventory of toponym projects has not existed, and eliciting what has been completed where, with whom, and by whom has required long searches through academic and grey literature. In this paper, we inventory Indigenous toponymy projects in the Canadian North, and document our efforts to produce a publicly accessible index where toponymy projects can be found via maps. New or unknown resources can be added by users. Our purpose, here, is to document the production of this resource and to increase awareness of toponymical resources among communities, researchers, scientists, and other stakeholders. We reflect on knowledge gained through construction of the index and make observations on trends in Inuit toponym research through time. We argue for renewed efforts across arctic sciences to recognize Inuit-environment relationships through reference to place names and the ecological histories they encapsulate, and we provide considerations for future work.journal articl
Important factors affecting transportation for shippers and potential demand for the Northeast Passage: A conjoint analysis of Japan
No full textThis study utilized choice-based conjoint analysis, along with conditional logit to identify the following three research questions: RQ1: Which factor of the route is important for sippers in marine transport? RQ2: What is the potential demand for the NEP? How does the shipping cost alter the demand? RQ3: Which industry exhibits a high potential demand for the NEP? According to the results, Shipping Time, Percent Delay, Container Temperature, and Shipping Cost impact route selection by shippers. The following order was determined in terms of importance: Cost > Delay > Time > Temperature. The following values were found for the marginal willingness to pay: USD 31.7/FEU for one-day reduction, USD 35.2/FEU for 1% reduction in the delay rate of 1–3 days, and USD 456.0/FEU for a decrease in temperature inside the container from 15 to 45 °C to 5–20 °C. Furthermore, the potential probability of the selection of NEP is 39.4% if the cost is equal. When the cost increases from USD 2585/FEU to USD 2100–2150/FEU, the share becomes equal to the SCR. The Agriculture and Fisheries industry exhibited the highest potential demand, while the Chemical industry exhibited the least demand. These results led to three policy implications. It should be noted, however, that the accuracy of the analysis remains debatable because it is not random sampling.journal articl
Prompt gamma-ray analysis of Antarctic meteorites (2) – CM chondrites
Get PDFThe 15th Symposium on Polar Science/Ordinary sessions [OA] Antarctic Meteorite, Thu. 5 Dec. / 3F Conference room, The Institute of Statistical Mathematicsconference outpu