| 1. |
- Qi, Di, et al.
(författare)
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Climate change drives rapid decadal acidification in the Arctic Ocean from 1994 to 2020
- 2022
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 377:6614, s. 1544-1550
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Tidskriftsartikel (refereegranskat)abstract
- The Arctic Ocean has experienced rapid warming and sea ice loss in recent decades, becoming the first open-ocean basin to experience widespread aragonite undersaturation [saturation state of aragonite (Warag) < 1]. However, its trend toward long-term ocean acidification and the underlying mechanisms remain undocumented. Here, we report rapid acidification there, with rates three to four times higher than in other ocean basins, and attribute it to changing sea ice coverage on a decadal time scale. Sea ice melt exposes seawater to the atmosphere and promotes rapid uptake of atmospheric carbon dioxide, lowering its alkalinity and buffer capacity and thus leading to sharp declines in pH and Warag. We predict a further decrease in pH, particularly at higher latitudes where sea ice retreat is active, whereas Arctic warming may counteract decreases in Warag in the future.
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| 2. |
- Cai, Wei-Jun, et al.
(författare)
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Carbon fluxes across boundaries in the Pacific sector of the Arctic Ocean in a changing environment
- 2014
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Ingår i: THE PACIFIC ARCTIC REGION: ECOSYSTEM STATUS AND TRENDS IN A RAPIDLY CHANGING ENVIRONMENT. - : Springer. - 9789401788625
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Bokkapitel (refereegranskat)abstract
- In this chapter we examine carbon fluxes across the land-ocean and air-sea boundaries in the Pacific Arctic Region (PAR) as well as ocean gateway exchanges in the region. The latter ocean gateway fluxes includes dissolved inorganic carbon (DIC) transported into the area from the Pacific Ocean via Bering Strait and exported to the Atlantic Ocean via the Canadian Archipelago, as well as exchanges between various sub-regions within the system. We emphasize the changes in the magnitudes of these fluxes in the context of climate warming and sea-ice melt, as well as other hydrological cycle changes in the Arctic. We conclude that while the inflow of DIC from the Pacific Ocean is relatively well quantified (623 ± 78 Tg C yr-1; T=1012), the intermittent input flux from the East Siberian Sea (ESS) is not (32 ± 16 Tg C yr-1). Most of the uncertainty is associated with variability in actual water flux rather than DIC content of this water, and thus is viewed as a systematic error in our DIC mass balance analysis. Furthermore, we determined an export flux of 749 Tg C yr-1 to the Atlantic Ocean, with the caveat that this term has unknown uncertainty due to a paucity of DIC data from the Canadian Archipelago. Within the PAR, the Chukchi Sea is the dominant site for atmospheric carbon dioxide (CO2) uptake (up to 35-46 Tg C yr-1), while the Beaufort Sea (2.9 Tg C yr-1) and the Canadian Archipelago (~10 Tg C yr-1) take-up much less CO2 with latter potentially a weak source of CO2 to the atmosphere during certain times of the year. Additionally, the ESS shelf is a net source of CO2 for the atmosphere (< 5 Tg C yr-1). Summertime CO2 uptake capacity in the deep Canada Basin has increased greatly over the past few years as sea-ice retreat progresses rapidly though earlier flux estimates may be on the high end. Overall, the PAR appears to export more DIC to the Atlantic Ocean than it receives through the combined inputs from the Pacific Ocean, the ESS, the atmosphere, and the rivers by a small amount (45 Tg C yr-1 or 6%). Our preliminary DIC budget suggests that the PAR is probably weakly net heterotrophic (i.e., respiring more organic carbon, OC, than its production). This tentative assessment of the trophic status of the PAR, if supported by further data, suggests that in addition to labile OC produced in the highly productive marginal seas, some riverine and coastal erosion-derived OC is also recycled within this Arctic system. As warming progresses, the Arctic Ocean may produce and export more DIC to the Atlantic Ocean. Whether this change will turn the Arctic Ocean into a weaker CO2 sink or even a CO2 source for the atmosphere is uncertain and dependent on multiple factors that control the rate of surface water CO2 increase versus the rate of the atmospheric CO2 increase.
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| 3. |
- Jiao, Liping, et al.
(författare)
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Persistent toxic substances in remote lake and coastal sediments from Svalbard, Norwegian Arctic : Levels, sources and fluxes
- 2009
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Ingår i: Environmental Pollution. - : Elsevier. - 0269-7491 .- 1873-6424. ; 157:4, s. 1342-1351
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Tidskriftsartikel (refereegranskat)abstract
- Surface sediments from remote lakes and coastal areas from Ny-Ålesund, Svalbard, Norwegian Arctic were analyzed for polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). Relatively high levels of PAHs were encountered from several lakes from Ny-Ålesund, which were within the range of levels reported for European high mountain lakes and some urban/industrialized areas in the world, pointing to the role of remote Arctic lakes as potential reservoir of semi-volatile organic compounds. Specific patterns of PBDEs were observed, showing higher concentrations of lower brominated compounds such as BDE-7, 17 and 28. Estimated surface sediment fluxes of PAHs in Ny-Ålesund remote lakes were similar to those observed for some European high mountain lakes. The current PAH levels in sediments from three lakes exceeded Canadian sediment quality guidelines, suggesting the presence of possible risks for aquatic organisms and the need for further studies.
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| 4. |
- Shao, Mingjiao, et al.
(författare)
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High-Performance Biodegradable Energy Storage Devices Enabled by Heterostructured MoO3-MoS2 Composites
- 2023
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Ingår i: Small. - : Wiley-VCH Verlagsgesellschaft. - 1613-6810 .- 1613-6829. ; 19:10
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Tidskriftsartikel (refereegranskat)abstract
- Biodegradable implantable devices are of growing interest in biosensors and bioelectronics. One of the key unresolved challenges is the availability of power supply. To enable biodegradable energy-storage devices, herein, 2D heterostructured MoO3–MoS2 nanosheet arrays are synthesized on water-soluble Mo foil, showing a high areal capacitance of 164.38 mF cm−2 (at 0.5 mA cm−2). Employing the MoO3–MoS2 composite as electrodes of a symmetric supercapacitor, an asymmetric Zn-ion hybrid supercapacitor, and an Mg primary battery are demonstrated. Benefiting from the advantages of MoO3–MoS2 heterostructure, the Zn-ion hybrid supercapacitors deliver a high areal capacitance (181.86 mF cm−2 at 0.5 mA cm−2) and energy density (30.56 µWh cm−2), and the Mg primary batteries provide a stable high output voltage (≈1.6 V) and a long working life in air/liquid environment. All of the used materials exhibit desirable biocompatibility, and these fabricated devices are also fully biodegradable. Demonstration experiments display their potential applications as biodegradable power sources for various electronic devices.
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