Polar Research (E-Journal)
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Mesoscale atmospheric processes over an Arctic fjord as observed during a research aircraft campaign in winter
No full textUnique research aircraft observations were conducted within an Arctic fjord in Svalbard during three days in March 2013. Wijdefjorden is 110 km long, 5–15 km wide and has a north–south axis. Two-thirds of the fjord were covered by land-fast sea ice, but the northern part of the fjord was open. On two days the flow over the fjord was largely controlled by orographic channelling of the north-easterly wind, and on all three days a cold-air mass accumulated over the sea ice in the fjord and gradually propagated towards the open sea in the north. An ice breeze (analogous to land breeze) circulation, due to a strong temperature gradient across the sea-ice edge, was a key driver of the southerly near-surface wind over the fjord. On two days, the cold-air mass reached the open sea and the near-surface air mass warmed rapidly by several Kelvins. On one day, the channelled northerly flow pushed the cold-air mass to the south, from where it gradually propagated back to the north after the channelled flow had weakened. The results suggest that the channelling of the large-scale flow in the fjord can suppress the ice breeze to a shallow near-surface layer and even push the cold-air mass far south of ice edge. The near-surface air temperature and wind fields that were based on the Copernicus Climate Change Service Arctic Regional Reanalysis (CARRA) data set included large errors because CARRA did not have any sea ice in the fjord
Quantifying floridean starch storage patterns in Arctic rhodoliths: blue carbon implications
No full textRhodoliths composed of crustose coralline algae (CCA) are marine calcifiers of global significance. Here, we investigate how floridean starch storage patterns of Arctic rhodoliths from Svalbard are affected by environmental conditions. Quantifying the amount of starch in photomosaic scans of rhodolith slabs via amylopectin–iodine complex formation, we found that shallow water rhodoliths contain significantly higher starch percentages compared to the deeper-water dwellers. We conclude that the observed starch patterns are mainly controlled by water depth because light and rhodolith turnover frequency both decrease in deeper waters. Regarding rhodolith turnover, the occasional burial of turned rhodoliths in deeper waters can result in a dieback of the outer CCA thallus areas, which contain important starch supplies. As rhodoliths are both calcifiers and photoautotrophs, we highlight their relevance in potentially contributing to global blue carbon, that is, their role as a marine carbon sink. In this context, our quantification approach of floridean starch patterns in rhodoliths provides a straightforward basis for further studies on this topic
Relative importance of nanoflagellate grazing and viral lysis for the mortality of heterotrophic bacteria and Synechococcus spp. in a high-latitude fjord (Adventfjorden, Svalbard) during the summer
No full textViral lysis and grazing play crucial but distinct roles in microbial community dynamics and carbon cycling. Yet, their relative influence on the abundance of heterotrophic bacterial and picophytoplankton populations, especially in Arctic fjords, remains poorly understood. To address this knowledge gap, we conducted modified dilution experiments in Adventfjorden, Svalbard, to quantify microbial growth, grazing pressure and virus-induced mortality. Our results showed that the abundance of virus-like particles (VLP) ranged between 1.4 and 8.9 × 106 viruses ml−1, with a negative correlation to salinity. This suggests that freshwater inputs, such as meltwater, could contribute to higher VLP abundance in these waters. The VLP-to-bacteria ratio varied between 9.8 and 700.9, with a large variation below a salinity of 28 PSU and an inverse correlation with salinity. Grazing, primarily by nanoflagellates, emerged as the dominant factor in reducing heterotrophic bacterial and Synechococcus spp. populations, accounting for 12–55% and 20–110% of their production losses, respectively. This study was conducted in summer, when meltwater discharges entered coastal waters in Svalbard fjords at an extremely high rate, providing an opportunity to study microbial processes under projected future warming conditions
When does fakery in nature documentaries go too far and what about the scientists in them?
No full textThis editorial reflects on deception in nature documentaries, ranging from trifling and, arguably, justifiable tricks to the outright hoaxes that gravely mislead viewers and damage public trust in science. Examples are drawn from Disney, BBC, Discovery Channel, Animal Planet and other productions. Scientists who are asked to appear in nature documentaries are advised to proceed with caution and to safeguard their right to speak publicly about falsehoods and dupery in such productions. The availability of inexpensive video-fabricating applications raises the spectre of additional problems
Svalbard Rock Vault: towards safeguarding geological cores and borehole data
No full textContinuous sedimentary drill cores provide crucial data for deciphering past climate variations and characterizing the subsurface for the energy industry (e.g., coal, petroleum, CO2 storage, geothermal energy). The Norwegian High-Arctic archipelago of Svalbard offers a diverse geological record that has been investigated by geoscientists for both scientific and applied projects, with hundreds of boreholes drilled over the past century. Unfortunately, much crucial data, including physical material from the boreholes, have been lost. The Svalbard Rock Vault project aims to safeguard drill cores, cuttings and hand samples from Svalbard and facilitate their scientific reuse. We aim to establish a physical core storage repository in, or near, Longyearbyen, Svalbard. In parallel, ongoing digitization and data integration efforts are improving access to complementary non-physical material, including hard-to-access reports, wireline logs and interpretations. In this contribution, we report on the motivation and background of the Svalbard Rock Vault project, synthesize current knowledge about physical subsurface material from Svalbard, and present a vision of an improved physical core storage facility near Longyearbyen
Representation of Dense Shelf Water formation by global oceanic reanalyses
No full textThis study evaluates the representation of Dense Shelf Water (DSW) formation in the Southern Ocean by two global oceanic reanalyses: GLORYS2v4 and ORAS5. We found that GLORYS2v4 generally represents larger areas and more consistent temporal patterns of DSW compared to ORAS5. This latter reanalysis significantly underestimates the extent and frequency of DSW formation. Although both reanalyses show good statistical agreement with the World Ocean Circulation Experiment data set, with a root mean squared error of approximately 0.7, a mean absolute percentage error of 1.16% and an r value of 0.99, ORAS5 fails to reproduce the expected sea-surface salinity trend, exhibiting a negative trend across most of the Southern Ocean. This may lead to a weak representation of the water-mass formation processes in the region, thereby affecting its ability to satisfactorily represent the Meridional Overturning Circulation and the global thermohaline circulation. These discrepancies are attributed to the nudging process used for the sea-surface temperature in the ORAS5 model. This study highlights the importance of oceanic reanalyses to validate climate modelling results, in particular in high-latitude regions, where observations are scarce and crucial for understanding global climatic changes
Larsen’s cairn: the birth of a new historical site in Antarctica
No full textThis article describes the history of Larsen’s cairn, one of the oldest historical sites in Antarctica, and explains how it became one of the most recently declared Historical Site and Monuments (HSMs) on the continent. Norwegian explorer and whaler Carl Anton Larsen constructed the cairn on Marambio/Seymour Island during the Norwegian Whaling Expedition in 1892. Officially designated as C.A. Larsen Multiexpedition Cairn (HSM 94), this site featured in several episodes of Antarctic history, spanning three periods of Antarctic history: Antarctic whaling, the Heroic Age of Antarctic exploration, and a period characterized by the installation of permanent stations at the end of World War II. Argentina, Norway, Sweden and the UK have all had some involvement in the cairn and all four nations now share an administrative role vis-à-vis the HSM, making it the HSM with the largest number of administrators to date. Adding to its significance, the cairn is linked to the earliest phase of invertebrate palaeontology in Antarctica and can also be considered the first material remains of the Norwegian presence in Antarctica
Environmental management and stewardship practices in Antarctic science and tourism: do they align with environmental concerns?
No full textIn the Antarctic Peninsula, tourism and science operations are interconnected and overlap spatially and temporally, sharing practices aimed at reducing and mitigating the human footprint. Guided by the concepts of environmental management and environmental stewardship, we examined how these environmental practices address the various types of environmental impacts generated by these operations. For this, we categorized the environmental impacts identified in the literature and conducted an expert survey to assess which of these impact categories are the most concerning. Then, we consulted the Inspection Reports of the Antarctic Treaty Consultative Parties, tour operators’ annual reports and documents from the International Association of Antarctica Tour Operators to capture environmental management and stewardship practices. Finally, we evaluated to what extent these practices address the categories of impacts. We identified 68 environmental practices for science and 63 for tourism operations. We classified them into nine categories, which range from mitigating soil and water contamination to limiting landscape modifications, minimizing impacts on flora, fauna and ecosystems and reducing greenhouse gas emissions. We identified a significant number of practices addressing local and specific impact categories. In contrast, a smaller number of practices were identified for the impacts that are most concerning in terms of their geographical scale, duration and severity, according to our experts’ survey. We discuss that the number of practices does not reflect their effectiveness, and the positive influence of some practices in building formal management instruments. Greater collaboration among stakeholders will improve the protection of the Antarctic continent
A 90-year record of glacier changes in the Novaya Zemlya Archipelago, Russian High Arctic
No full textGlacial retreat in the Russian High Arctic, particularly in the Novaya Zemlya Archipelago (NZA), is emblematic of global warming. Some global models project that, by 2100, sea-level rise contributions from melting glaciers in this region could be comparable to contributions from Antarctica’s and Greenland’s peripheral glaciers. However, historical glacier change in the NZA remains poorly known. Here, we present the longest decadal chronology of glacier change in the NZA to date, including a 90-year record (ca. 1931–2021) of frontal length change, and a 70-year record (1952–2021) of glacier area change. Using a combination of survey records, historical maps and satellite imagery, we analyse changes for 63 outlet glaciers, representing 86% of the NZA’s total ice mass. Our results show that the average frontal retreat rate increased each decade since the early 1970s, reaching a peak retreat rate of 65 m a-1 between 2011 and 2021. Glaciers terminating in the Barents Sea experienced the greatest losses, retreating an average of 4.2 km (11.6%) since 1952. During this time, the total glacier area decreased by 1606 km2 (10%). We identified increasing summer air and sea-surface temperatures as key drivers of accelerated glacier retreat, with peak air and sea-surface temperatures occurring from 2011 to 2021, corresponding to the period with the fastest retreat rates and the largest glacier area loss
Arctic shipping 2013–2022: the traffic has grown, with big variation between regions, seasons and ship types
No full textThis article analyses decadal changes in Arctic ship traffic from 2013 to 2022, using data from the Arctic Ship Traffic Data system (ASTD). Shipping in waters affected by sea ice has grown, but how much depends on geographical definitions. The Polar Code area had an average annual growth of 8.7%, mainly due to more traffic in the Barents Sea, where most Arctic ship traffic occurs. Where analysts set the southern boundary of the Barents Sea significantly influences the statistics, for example, to what extent fishing vessels dominate Arctic shipping. Reports on Arctic shipping should consider the significant intra-Arctic variations in activity levels, growth rates and traffic composition. The Kara Sea experienced the biggest annual growth rate—14% on average—because of petroleum projects that have introduced big oil and gas tankers. In contrast, there is minimal activity and growth in the Large Marine Ecosystems of the Northern Canadian Archipelago and the Central Arctic Ocean. Even though the winter traffic has grown in the Barents Sea, the Kara Sea and Baffin Bay, the activities there remain distinctly seasonal. In other seas, ships almost vanish in winter. Transit shipping over the Arctic is still insignificant in a global context. The standard reports in the ASTD are important for understanding Arctic shipping and should be improved. In particular, the Polar Code area needs to be subdivided to enable consistent reporting on overall pan-Arctic and intra-Arctic developments. Definitions for transit traffic should also be agreed upon and opportunities for automatic reporting accordingly investigated