1928 research outputs found
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Characteristics of Antarctic aerosol composition during the Australian fires of 2019–2020
Full text linkDuring the 36th Chinese National Antarctic Research Expedition, aerosol samples were gathered from the Ross Sea in Antarctic to assess the climatic impact of the Australian fires that occurred in 2019–2020. The chemical compositions, including levoglucosan (Lev) and its isomers, galactosan (Gan) and mannosan (Man), were analyzed. Principal component analysis helped identify the potential sources of these chemical components. By combining backward trajectories with the ratios of CLev/CMan and CMan/CGan, it was further inferred that Australia might be the potential source region for biomass burning. The radiative forcing resulting from biomass burning was evaluated using the Santa Barbara DISORT Atmospheric Radiative Transfer (SBDART) model, which revealed that black carbon emitted from biomass burning could slightly warm the atmosphere (+0.52 W·m–2) while causing slightly cooling at the surface (–0.73 W·m–2) and the top of the atmosphere (–0.22 W·m–2) over the Ross Sea
Sustainable observations of landfast sea ice in the cryosphere: a case study at the Liaodong Bay, Bohai Sea, North China
Full text linkSustainable monitoring of sea ice is crucial for better understanding air-ice-ocean interactions and identifying new processes. However, it is an expensive process particularly for the polar cryosphere environment. The seasonal ice-covered sea area can be used as a test bed for cryosphere-related process studies due to convenient access and conduction of field work, and the seasonal regime variation of the Arctic sea ice resulting from climate changes. In this paper, a small landfast sea ice monitoring program has been carried out for four consecutive seasons at Jiangjunshi Port, the Bohai Sea, North China, analyzing the temperature and salinity of air, ice and ocean and discussing the influence on mechanical properties. The effect of air temperature on sea ice temperature is focused. During low-temperature periods, the maximum correlation coefficient between air temperature and ice temperature, along with temperature fluctuation within ice, decreases as ice depth increases. Ice salinity was measured using ice core sampling and ice crumb sampling, with ice crumb salinity twice larger compared to ice core sampling when the ice temperature is −3 ℃. Ice salinity variations with ice temperature and the salinity profiles were fitted. Analysis of the profiles of under-ice seawater salinity reveals the presence of a high-salinity layer near the bottom of sea ice during the initial stage of sea ice growth. Based on the dynamic changes in sea ice temperature and sea ice salinity, this study evaluates the mechanical properties of sea ice, with the fitting determination coefficients of the obtained parameterized formulas significantly better than those reported in current research
Methods for ice velocity mapping in West Antarctica using historical optical satellite images
Full text linkThe Antarctic Ice Sheet harbors more than 90% of the Earth ice mass, with significant losses experienced through dynamic thinning, particularly in West Antarctica. The crucial aspect of investigating ice mass balance in historical periods preceding 1990 hinges on the utilization of ice velocities derived from optical satellite images. We employed declassified satellite images and Landsat images with normalized cross correlation based image matching, adopting an adaptive combination of skills and methods to overcome challenges encountered during the mapping of historical ice velocity in West Antarctica. A basin-wide synthesis velocity map encompassing the coastal regions of most large-scale glaciers and ice shelves in West Antarctica has already been successfully generated. Our results for historical ice velocities cover over 70% of the grounding line in most of the West Antarctic basins. Through adjustments, we uncovered overestimations in ice velocity measurements over an extended period, transforming our ice velocity map into a spatially deterministic, temporally average version. Among all velocity measurements, Thwaites Glacier exhibited a notable spatial variation in the fastest ice flowline and velocity distribution. Overestimation distributions on Thwaites Glacier displayed a clear consistency with the positions of subsequent front calving events, offering insights into the instabilities of ice shelves
Country Reports 2022-2023: Reports from the Adhering Bodies of the International Permafrost Association
Full text linkResearch and exploration of direct current power supply and distribution systems for Antarctic research stations
Full text linkThe power supply and distribution systems for Antarctic research stations have special characteristics. In light of a worldwide trend toward a gradual increase in the application of renewable energy, an analysis was performed to assess the feasibility of achieving a direct current power supply and distribution at Antarctic research stations by comparing the characteristics of direct current and alternating current electricity. Research was also performed on the status quo and future trends in direct current power supply and distribution systems in Antarctica research stations in combination with case studies
Central Arctic Ocean Fisheries Agreement: China’s role and implications for sustainable Arctic governance
Full text linkThe opening of the Arctic Ocean has prompted the signing of the Agreement to Prevent Unregulated High Seas Fisheries in the Central Arctic Ocean (CAOF Agreement) by 10 parties, including the five Arctic Ocean coastal states and the world’s leading distant-water fishing states. The negotiation process, initiated by the United States, progressed in two stages: the “A5 process” and the “A5+5 process”. The CAOF Agreement sets a precedent for cooperation between Arctic and non-Arctic states in managing Arctic high seas resources. It also incorporates several innovative management approaches for Arctic fisheries, such as the precautionary approach, ecosystem-based management, and state-of-the-art scientific knowledge as the basis for decision-making. Since 2015, China has actively participated in the negotiation and implementation of the CAOF Agreement. This article carefully analyzes the background and progressiveness of the CAOF Agreement and examines the responsibility that all state parties share concerning the sustainable use of marine living resources in the Central Arctic Ocean. The article also reviews China’s interests and engagement in the Arctic region, with particular attention to its participation in the CAOF Agreement. Finally, the article concludes by discussing China’s role and implications for sustainable Arctic governance and its broader implications for evolving international environmental and ocean governance
Germany's Arctic Policy Guidelines - Germany and the Arctic in the context of the climate crisis and the Zeitenwende
Full text linkVision for Nordic Defence Cooperation (NORDEFCO)
Full text linkThe Nordic countries are committed to strengthening the deterrence and defence of the Nordic region and the Euro-Atlantic Area. The Nordic countries are prepared and able to conduct combined joint military operations to manage both present and future challenges together and with allies of the North Atlantic Treaty Organisation. Nordic Defence Cooperation complements and contributes to European and transatlantic security and collective defence
Antarctic red algae in dye-sensitized photoelectrochemical cells for water splitting
Full text linkPhycoerythrin extracted from Antarctic red seaweeds shows promising characteristics to be applied as an anode sensitizer in water-splitting photoelectrochemical cells. Under light irradiation and using an LED lamp, the red-colored protein shows an interesting ability to profit the incident light, as confirmed by the presence of oxygen bubbles next to the electrode surface without applying any external potential. Our results showed that the addition of iodide is helpful to allow the regeneration of the dye; nevertheless, oxygen evolution is not favored. Thermodynamics analysis of the involved semi-reactions is also helpful to understand the observed results. The exploration of Antarctic resources offers then an alternative for the development of green energies, with a particular focus on their use as sensitizers to profit from the sunlight in water-splitting as well as in photovoltaic devices
