Cold-seep benthic communities in the Arctic exist at the nexus of two extreme environments; one reflecting the harsh physical extremes of the Arctic environment and another reflecting the chemical extremes and strong environmental gradients associated with seafloor seepage of methane and toxic sulfide-enriched sediments. Recent ecological investigations of cold seeps at numerous locations on the margins of the Arctic Ocean basin reveal that seabed seepage of reduced gas and fluids strongly influence benthic communities and associated marine ecosystems. These Arctic seep communities are mostly different from both conventional Arctic benthic communities as well as cold-seep systems elsewhere in the world. They are characterized by a lack of large specialized chemo-obligate polychetes and mollusks often seen at non-Arctic seeps, but, nonetheless, have substantially higher benthic abundance and biomass compared to adjacent Arctic areas lacking seeps. Arctic seep communities are dominated by expansive tufts or meadows of siboglinid polychetes, which can reach densities up to >3 × 105 ind.m–2. The enhanced autochthonous chemosynthetic production, combined with reef-like structures from methane-derived authigenic carbonates, provides a rich and complex local habitat that results in aggregations of non-seep specialized fauna from multiple trophic levels, including several commercial species. Cold seeps are far more widespread in the Arctic than thought even a few years ago. They exhibit in situ benthic chemosynthetic production cycles that operate on different spatial and temporal cycles than the sunlight-driven counterpart of photosynthetic production in the ocean’s surface. These systems can act as a spatio-temporal bridge for benthic communities and associated ecosystems that may otherwise suffer from a lack of consistency in food quality from the surface ocean during seasons of low production. As climate change impacts accelerate in Arctic marginal seas, photosynthetic primary production cycles are being modified, including in terms of changes in the timing, magnitude, and quality of photosynthetic carbon, whose delivery to the seabed fuels benthic communities. Furthermore, an increased northward expansion of species is expected as a consequence of warming seas. This may have implications for dispersal and evolution of both chemosymbiotic species as well as for background taxa in the entire realm of the Arctic Ocean basin and fringing seas.
The large declines in Arctic sea-ice age and extent over the last decades could have altered the diversity of sea-ice associated unicellular eukaryotes (referred to as sea-ice protists). A time series from the Russian ice-drift stations from the 1980s to the 2010s revealed changes in community composition and diversity of sea-ice protists from the Central Arctic Ocean. However, these observations have been biased by varying levels of taxonomic resolution and sampling effort, both of which were higher in the early years at drift stations on multiyear sea ice (MYI) in the Central Arctic Ocean. We here combine the Russian ice-drift station data with more recent data to (1) identify common sea-ice protists (in particular diatoms) in drifting sea ice of the Central Arctic Ocean; (2) characterize the potential change in such communities over 35 years in terms of species number and/or community structure; and (3) relate those shifts to relevant environmental factors. In terms of relative abundance, pennate diatoms were the most abundant sea-ice protists across the Arctic, contributing 60% on average of counted cells. Two pennate colony-forming diatom species, Nitzschia frigida and Fragilariopsis cylindrus, dominated at all times, but solitary diatom species were also frequently encountered, e.g., Cylindrotheca closterium and Navicula directa. Multiyear sea ice contained 39% more diatom species than first-year ice (FYI) and showed a relatively even distribution along entire sea-ice cores. The decrease in MYI over the last decades explained the previously reported decreases in sea-ice protist diversity. Our results also indicate that up to 75% of diatom species are incorporated into FYI from the surrounding sea ice and the water column within a few months after the initial formation of the ice, while the remaining 25% are incorporated during ice drift. Thus, changing freeze-up scenarios, as currently witnessed in the Central Arctic, might result in long-term changes of the biodiversity of sea-ice protists in this region.
Half of the Arctic Ocean is deep sea (>1000 m), and this area is currently transitioning from being permanently ice-covered to being seasonally ice-free. Despite these drastic changes, it remains unclear how organisms are distributed in the deep Arctic basins, and particularly what feeds them. Here, we summarize data on auto- and heterotrophic organisms in the benthic, pelagic, and sympagic realm of the Arctic Ocean basins from the past three decades and put together an organic carbon budget for this region. Based on the budget, we investigate whether our current understanding of primary and secondary production and vertical carbon flux are balanced by the current estimates of the carbon demand by deep-sea benthos. At first glance, our budget identifies a mismatch between the carbon supply by primary production (3–46 g C m−2 yr−1), the carbon demand of organisms living in the pelagic (7–17 g C m−2) and the benthic realm (< 5 g C m−2 yr−1) versus the low vertical carbon export (at 200 m: 0.1–1.5 g C m−2 yr−1, at 3000–4000 m: 0.01–0.73 g C m−2 yr−1). To close the budget, we suggest that episodic events of large, fast sinking ice algae aggregates, export of dead zooplankton, as well as large food falls need to be quantified and included. This work emphasizes the clear need for a better understanding of the quantity, phenology, and the regionality of carbon supply and demand in the deep Arctic basins, which will allow us to evaluate how the ecosystem may change in the future.
In recent years, special attention has been paid to the issues of rational nature management and ecological state of the natural environment of the Arctic zone, given the important economic, social and environmental role of this region. The active industrial development of the Arctic zone unambiguously leads to a change in the living conditions of marine biological resources. The Arctic plays an important role in Russian fisheries. The paper considers the conceptual provisions of rational nature management in the conditions of industrial development of the Russian Arctic and identifies the problems and conditions for sustainable development of the Russian fisheries.
Impactful communication remains a vexing problem for climate science researchers and public outreach. This article identifies a range of moving images and screen-based media used to visualize climate change, focusing especially on the Arctic region and the efforts of the United Nations. The authors examine the aesthetics of big data visualization of melting sea ice and glaciers made by NASA and similar entities; eye-witness, expert accounts and youth-produced documentaries designed for United Nations delegates to the annual COP events such as the Youth Climate Report; Please Help the World, the dystopian cli-fi narrative produced for the UN’s COP 15; and Isuma TV’s streaming of works by Indigenous practitioners in Nunavut.
Studying the distribution of zooplankton in relation to their prey and predators is challenging, especially in situ. Recent developments in underwater imaging enable such fine-scale research. We deployed the Lightframe On-sight Keyspecies Investigation (LOKI) image profiler to study the fine-scale (1 m) vertical distribution of the copepods Calanus hyperboreus and C. glacialis in relation to the subsurface chlorophyll maximum (SCM) at the end of the grazing season in August in the North Water and Nares Strait (Canadian Arctic). The vertical distribution of both species was generally consistent with the predictions of the Predator Avoidance Hypothesis. In the absence of a significant SCM, both copepods remained at depth during the night. In the presence of a significant SCM, copepods remained at depth in daytime and a fraction of the population migrated in the SCM at night. All three profiles where the numerically dominant copepodite stages C4 and C5 of the two species grazed in the SCM at night presented the same intriguing pattern: the abundance of C. hyperboreus peaked in the core of the SCM while that of C. glacialis peaked just above and below the core SCM. These distributions of the same-stage congeners in the SCMs were significantly different. Lipid fullness of copepod individuals was significantly higher in C. hyperboreus in the core SCM than in C. glacialis above and below the core SCM. Foraging interference resulting in the exclusion from the core SCM of the smaller C. glacialis by the larger C. hyperboreus could explain this vertical partitioning of the actively grazing copepodite stages of the two species. Alternatively, specific preferences for microalgal and/or microzooplankton food hypothetically occupying different layers in the SCM could explain the observed partitioning. Investigating the observed fine-scale co-distributions further will enable researchers to better predict potential climate change effects on these important Arctic congeners.
How real-world marine food webs absorb change, recover and adapt (that is, ecological resilience) to climate change remains problematic. Here we apply a novel approach to show how the complex changes in resilience of food webs can be understood with a small core set of self-organizing configurations that represent different simultaneously nested and multiple-species interactions. We identified a recent emergent pattern of an improving but possibly short-lived resilience of a highly observed Arctic marine food web (2004–2016), considered a harbinger of future Arctic change. The changes can be explained by continuing subsidiary inputs of Atlantic species that repair (self-organize) interactions within some configurations. Despite significant environmental perturbation, we found that the core ecological processes are maintained. We conclude that Arctic marine food webs can absorb and begin to adapt to ongoing climate change.
The Arctic stratospheric polar vortex usually forms in autumn, reaches its peak intensity in mid-winter and decays in spring. The polar vortex strength and persistence in the winter–spring period play an important role in stratospheric ozone depletion with the return of solar radiation in late winter. The polar vortex breakdown in most cases occurs under the influence of vertically propagating planetary Rossby waves. The increased activity of planetary waves was observed in 1984/1985, 1998/1999 and 2012/2013 and led to the polar vortex breakdown in mid-winter, after which it was not observed for more than a month. In this study, Arctic sea ice loss is considered as the most likely cause of the increased activity of planetary waves resulting in the unusual weakening of the Arctic polar vortex. Arctic sea ice extent was a record low in autumn 1984, 1998 and 2012 in the Beaufort Sea, the Canadian Arctic Archipelago and the Central Arctic.
Coastal fishery systems in the Arctic are undergoing rapid change. This paper examines the ways in which Inuit fishers experience and respond to such change, using a case study from Pangnirtung, Canada. The work is based on over two years of fieldwork, during which semi-structured interviews (n = 62), focus group discussions (n = 6, 31 participants) and key informant interviews (n = 25) were conducted. The changes that most Inuit fishers experience are: changes in sea-ice conditions, Inuit people themselves, the landscape and the seascape, fish-related changes, and changes in weather conditions, markets and fish selling prices. Inuit fishers respond to change individually as well as collectively. Fishers’ responses were examined using the characteristics of a resilience-based conceptual framework focusing on place, human agency, collective action and collaboration, institutions, indigenous and local knowledge systems, and learning. Based on results, this paper identified three community-level adaptive strategies, which are diversification, technology use and fisheries governance that employs a co-management approach. Further, this work recognised four place-specific attributes that can shape community adaptations, which are Inuit worldviews, Inuit-owned institutions, a culture of sharing and collaborating, and indigenous and local knowledge systems. An examination of the ways in which Inuit fishers experience and respond to change is essential to better understand adaptations to climate change. This study delivers new insights to communities, scientists, and policymakers to work together to foster community adaptation.
Our goal is to study the role of demographic change in the development and spread of maritime adaptations in the North American Arctic over the last 6000 years. We compile and analyze a regional radiocarbon database (n = 935) for northern Alaska, using Oxcal to analyze demographic patterns in summed probability distributions. We find that northern Alaskan populations grew significantly over the last 4500 years, although growth was punctuated by three periods of decline from approximately 3700 to 3125 cal BP, 1000 cal BP, and 600 cal BP. We assess possible alternative explanations for the observed demographic patterns (e.g. calibration and taphonomic effects, investigator bias). Region-wide erosion and calibration effects likely contribute to the dearth of radiocarbon dates around 1000 cal BP, and sampling bias may contribute to the post-600 cal BP decline. However, we conclude that the overall pattern reflects regional population growth, decline, and recovery. Population growth predates intensification of marine resource procurement by at least 1200 years; we hypothesize that population growth was a possible driver for late Holocene marine intensification in the Arctic. These findings have further implications for understanding the process of intensification and the development of complexity in coastal hunter-gatherer societies.