Polar Research最新文献

Svalbard has long been thought to represent the easternmost realm of the Ellesmerian Orogeny in the late Devonian or early Mississippian (Svalbardian tectonic event). Several authors do not agree and present alternative interpretations of the observed structures in older and more recent articles. This article discusses a number of issues that, in our opinion, are not sufficiently considered in those works, but which are essential for the understanding of the Svalbardian tectonic event: (1) the possibility of re-deposited palynomorphs in the discussion of the deformational ages, (2) the age and structural setting of the crucial Adriabukta Formation in southern Spitsbergen, and (3) the presence and nature of the Svalbardian angular unconformity in central and southern Spitsbergen.

The range of tularemia, a disease caused by the bacterium Francisella tularensis, may expand alongside climate change in the North. Transmission occurs via biting arthropods, contaminated water sources, infected animal tissues and fluids and even aerosolized bacteria. Little research has been published on F. tularensis in northern Canada. We investigated whether Rangifer (caribou and reindeer) in Canada and Alaska are exposed to F. tularensis, as they provide significant cultural and subsistence value. From 2016 to 2020, 336 serum samples were collected from Rangifer across 17 herds, including captive reindeer in Alaska (n = 30) and wild caribou across Canada (n = 306) during collaring or harvesting efforts. Using a microagglutination test, we detected antibodies against F. tularensis in 7% of captive reindeer (CI₉₅ 2–21), 6% of migratory tundra caribou (CI₉₅ 4–11) and 10% of mountain woodland caribou (CI₉₅ 6–17), with the highest seroprevalence observed in animals from Nunavut (17%) and British Columbia, Canada (18%). Ten of the herds (n = 10/17; 59%) had at least one positive animal. Evidence of exposure to F. tularensis indicates that further studies are needed to characterize sources of transmission for Rangifer species and any potential health effects following infection.

The stratospheric polar vortex (SPV) weakening is linked to surface circulation changes. This study employs statistical analysis using reanalysis data to compare the anomalous SPV behaviour in the Northern (NH) and Southern (SH) hemispheres and its downward impacts on surface climate. The onset of annual SPV weakening occurs in mid-January and late September in the NH and SH hemispheres, respectively. Following the onset of SPV weakening, stratospheric polar cap height (PCH) anomalies were strongly correlated with tropospheric PCH anomalies. Significant cold anomalies were observed over Eurasia within 30 days after SPV weakening onset in the NH, whereas warming responses occurred in the SH 30–60 days after onset over Antarctica, except in the Antarctic Peninsula. These contrasting surface temperature responses to SPV weakening events in both hemispheres are the results of changes in the geopotential height in the troposphere, reminiscent of the change in geopotential height in the lower stratosphere, with a trough over Eurasia in the NH, and a higher height anomaly over East Antarctica in the SH. SPV changes have played a role in modulating surface climate via a downward influence on tropospheric circulation in recent decades. Even though they show a weakening trend in both hemispheres, SPV changes cannot fully explain long-term temperature trends. This is partially because SPV trends observed during the analysis period are relatively weak. This study enhances our understanding of the characteristics of the SPV coupled with troposphere circulation and can contribute to improved surface weather forecasting.

Corporate social responsibility (CSR) practices—by which companies contribute positively to society through their voluntary actions and initiatives—have advanced slowly in Russia. In Russia, the separation between the state and business is not clear, as is the difference between state-owned companies and nominally ‘private’—but still state-controlled—companies, and this has shaped CSR. CSR as practiced in Russia is state-initiated to an extent greater than that in many other countries. The Yamalo-Nenets Autonomous Okrug (YNAO), in the Russian Arctic, has a significant population of indigenous people whose way of life has traditionally been based on reindeer herding, fishing and other subsistence activities that are threatened by the ecological damage caused by the hydrocarbon extraction that is carried out in the region by large state-owned or state-controlled corporations such as the parastatal corporation Gazprom. CSR has the potential to ameliorate some of the problems faced by residents of the YNAO, including difficulties relating to transportation, the supply of goods, health care and environmental protection. To achieve this, the CSR roles of the different parties involved need to be better defined and the CSR actions should shift emphasis from modernizing the larger settlements of the YNAO to improving the lives of people who maintain a more traditional way of life on the tundra. Drawing on interviews, government and company documents, and Russian and non-Russian scholarly papers, this Perspective piece considers some aspects of CSR in the YNAO and points to topics of future research.

Antarctica and the Southern Ocean play vital roles in the Earth system, exerting significant influence on global atmospheric, cryospheric, and oceanic processes. Understanding the ongoing changes in Antarctica and their broader impact on global dynamics is imperative. Achieving this understanding necessitates dedicated and coordinated observations of environmental parameters in the region.

The Troll Observing Network (TONe) is Norway's proactive initiative to the call for sustained, coordinated, complementary, geographically spread, and societally relevant long-term observations from Antarctica. Centered around the Troll Research Station in Dronning Maud Land, a region characterized by limited data availability, TONe constitutes a comprehensive state-of-the-art observatory network, specifically designed for environmental observations for studying and monitoring of the atmosphere, terrestrial, and marine environments. TONe aims to facilitate broad and open access to observational data and shared services to the international research communities as a foundation for acquiring knowledge of societal significance.

TONe will, however, be a limited contribution the broader international data gathering effort required to underpin a strengthened understanding of Antarctica in the Earth system. TONE is an important initiative focused on a data sparse region of Antarctica, but has only substantial added value when seen in the context of similar ongoing and future efforts around the continent.

A cross-valley beach terrace in Iladalen, in the south-east of the island of Barentsøya, Svalbard, is interpreted as having been built by long-shore sediment transport and deposition, with its maximum height at about 88 m a.s.l., marking the marine limit at deglaciation. A whale vertebra—most probably from a bowhead whale (Balaena mysticetus)—was found embedded in the upper part of the littoral sediments at a height of ca. 80 m a.s.l., that is, about 8 m below the marine limit at deglaciation The bone is dated to 10 762 ± 137 cal yr BP, just a few hundred years after the generally accepted deglaciation of the coastal parts of Barentsøya, about 11 000 years ago. The vertebra’s age and altitudinal position fit well with the relative sea-level curve constructed for the north-eastern tip of the island of Edgeøya, some 29 km east–south-east of Iladalen.

Upper Triassic (Carnian) sandstones of the De Geerdalen Formation cored south of the island of Kvitøya (80°N), north-easternmost Svalbard, are described in terms of sedimentary facies and petrography and compared regionally in the northern Barents Shelf. The succession off Kvitøya is characterized by its great thickness and is dominated by deltaic deposits with high sand content of lithic–feldspathic compositions. Comparison of sediment facies and sandstone compositions with adjacent areas suggest that the succession off Kvitøya is part of a larger delta system with its main sediment source from the east. The delta sedimentation was terminated by marine transgression in the earliest Norian. The sandstone compositions off Kvitøya differ from nearby locations by the higher content of cherty rock fragments and reworked volcanic debris in the Kvitøya sandstone, which is most distinct in the lower part of the succession. Provenance signatures are investigated by mineral–chemical analysis of detrital feldspars, rock fragments, garnet and Cr-spinel, characterizing a wide variety of igneous, metamorphic and sedimentary terranes, including palaeo-Urals and areas farther to east. Additional, more proximal sediment source areas may also have existed that could explain the increased sediment thickness and the mineralogical immature sandstone compositions of the Carnian sediments off Kvitøya.