Polar Research (E-Journal)
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Impact of summertime anthropogenic emissions on atmospheric black carbon at Ny-Åesund in the Arctic
No full textMeasurements of equivalent black carbon (EBC), calculated from aethalometer measurements of light attenuation, were carried out in July 2011 at Ny-Ålesund in the Arctic. Highly elevated EBC concentrations were observed within the settlement of Ny-Ålesund, with a median value of 17 ng m−3, which was about two times the background level. Results from the ensemble empirical mode decomposition method suggested that about 60–80% of atmospheric EBC concentrations at Ny-Ålesund were from local emissions, while only 20–40% arrived via atmospheric transport. The estimated average local emission rate was 8.1 g h−1, with an uncertainty of approximately a factor of two. The pollution plume was confined to 10 km downwind of the settlement, with the total EBC deposition estimated to be 6.4–44 ng m−2 h−1. This may affect snow black carbon (BC) concentrations in nearby glaciated areas. The efficiencies of the long-range transport were estimated based on cluster analysis and potential precipitation contribution function, and the results implied that transport from western Europe is more efficient than from central Russia, on account of relatively rapid transport from western Europe and infrequent precipitation along this route. However, there was no correlation between air mass back-trajectories and EBC concentrations, suggesting that the contribution of long-range transport to EBC measured in Ny-Ålesund might be not significant in this season.Keywords: Equivalent black carbon; Ny-Ålesund; human influences; transport efficiency.(Published: 18 February 2014)Citation: Polar Research 2014, 33, 21821, http://dx.doi.org/10.3402/polar.v33.2182
Benthic foraminifera from the Lower Jurassic transgressive mudstones of the south-western Barents Sea - a possible high-latitude expression of the global Pliensbachian-Toarcian turnover?
No full textThe Lower Jurassic section of two commercial wells (7119/12-1 and 7119/12-2), drilled in the Hammerfest Basin, was analysed for foraminiferal assemblages in order to reconstruct palaeoenvironmental changes. Foraminifera occurred singularly in transgressive mudstone intervals of the Stø Formation in well 7119/12-1. High-energy marginal marine and offshore sandstones and freshwater sand- and mudstones were barren of foraminifera. Three distinct foraminiferal assemblages could be distinguished. They contain exclusively agglutinated taxa and have extremely low species diversities, indicating restricted environmental conditions. The main restricting factor was low salinity in strongly delta-influenced waters. Foraminiferal assemblage 1 is developed at the base of the Stø Formation and suggests transgressive, extremely hyposaline lagoonal conditions. Assemblages 2 and 3 occur in hyposaline prodelta shelf mudstones of the Stø Formation and reveal increased diversities in major local transgressive phases. The foraminiferal assemblages indicate Pliensbachian–Toarcian ages. The mudstones of the Stø Formation are regarded as a local expression of the global Pliensbachian–Toarcian turnover recording regional transgressive developments in the Toarcian.Keywords: Barents Sea; foraminifera; marginal marine environments; Early Jurassic; Pliensbachian–Toarcian turnover.(Published: 28 January 2014)Citation: Polar Research 2014, 33, 20206, http://dx.doi.org/10.3402/polar.v33.2020
Games in the Arctic: applying game theory insights to Arctic challenges
No full textWe illustrate the benefits of game theoretic analysis for assisting decision-makers in resolving conflicts and other challenges in a rapidly evolving region. We review a series of salient Arctic issues with global implications—managing open-access fisheries, opening Arctic areas for resource extraction and ensuring effective environmental regulation for natural resource extraction—and provide insights to help reach socially preferred outcomes. We provide an overview of game theoretic analysis in layman’s terms, explaining how game theory can help researchers and decision-makers to better understand conflicts, and how to identify the need for, and improve the design of, policy interventions. We believe that game theoretic tools are particularly useful in a region with a diverse set of players ranging from countries to firms to individuals. We argue that the Arctic Council should take a more active governing role in the region by, for example, dispersing information to “players” in order to alleviate conflicts regarding the management of common-pool resources such as open-access fisheries and natural resource extraction. We also identify side payments—that is, monetary or in-kind compensation from one party of a conflict to another—as a key mechanism for reaching a more biologically, culturally and economically sustainable Arctic future. By emphasizing the practical insights generated from an academic discipline, we present game theory as an influential tool in shaping the future of the Arctic—for individual researchers, for inter-disciplinary research and for policy-makers themselves.Keywords: Arctic futures; Arctic games; environmental regulation; resource contests; side payments; effective governance.(Published: 8 August 2014)Citation: Polar Research 2014, 33, 23357, http://dx.doi.org/10.3402/polar.v33.2335
Changes in meltwater chemistry over a 20-year period following a thermal regime switch from polythermal to cold-based glaciation at Austre Brøggerbreen, Svalbard
No full textOur long-term study gives a rare insight into meltwater hydrochemistry following the transition of Austre Brøggerbreen from polythermal to cold-based glaciation and its continued retreat. We find that the processes responsible for ion acquisition did not change throughout the period of records but became more productive. Two regimes before and after July/August 2000 were identified from changes in solute concentrations and pH. They resulted from increased chemical weathering occurring in ice-marginal and proglacial environments that have become progressively exposed by glacier retreat. Carbonate carbonation nearly doubled between 2000 and 2010, whilst increases in the weathering of silicate minerals were also marked. In addition, the end of ablation season chemistry was characterized by reactions in long residence time flow paths like those in subglacial environments, in spite of their absence in the watershed. Furthermore, the retreat of the glacier caused the sudden re-routing of meltwaters through its immediate forefield during 2009, which more than doubled crustal ion yields in this particular year and influenced chemical weathering in 2010 regardless of a low water flux. Such a “flush” of crustally derived ions can be meaningful for downstream terrestrial and marine ecosystems. We therefore find that, during glacier retreat, the recently exposed forefield is the most chemically active part of the watershed, making high rates of weathering possible, even when ice losses have caused a switch to cold-based conditions with no delayed subglacial drainage flowpaths. In addition, the drainage system reorganization events result in significant pCO2 depletion in an otherwise high pCO2 system.Keywords: High Arctic; Bayelva; meltwater geochemistry; chemical weathering in glacierized catchment; glacier retreat; climate change.(Published: 23 October 2014)Citation: Polar Research 2014, 33, 22779, http://dx.doi.org/10.3402/polar.v33.2277
The impact of seabirds on the content of various forms of phosphorus in organic soils of the Bellsund coast, western Spitsbergen
No full textIn areas isolated from direct human impact, such as Spitsbergen, environmental changes result mainly from natural processes, which include nutrient enrichment caused by seabirds. The objective of this study was to evaluate the degree of nutrient enrichment of organic soils fertilized by seabirds, indicated by the phosphorus content and transformations. This study encompassed two areas on the Bellsund coast. A profile without the influence of seabirds and profiles located at different distances from the colony of birds (0–150 m) were analysed. A sequential phosphorus fractionation method was used, and three inorganic P (Pi) fractions were obtained as a result: Pi-L (labile P), Pi-FeAl (P associated with Fe and Al) and Pi-CaMg (P associated with Ca and Mg); and two fractions of organic P (Po): Po-HuAc (P associated with humic acids) and Po-Res (residual P). Polar organic soils not subjected to the direct seabird impact contained amounts of total phosphorus (Pt) similar to organic soils in other climate zones. The presence of the seabird colony increased the Pt content and changed the distribution between the ratio of organic and inorganic P fractions. Within the inorganic P fraction, the Pi–CaMg component was dominant and its distribution was modified by the fertilizing effect of bird droppings. The nutrient enrichment of organic soils by birds in the polar zone was therefore very strong.Keywords: Phosphorus fractions; organic soils; seabirds; nutrient enrichment; Spitsbergen.(Published: 17 October 2014)Citation: Polar Research 2014, 33, 19986, http://dx.doi.org/10.3402/polar.v33.1998
Assessing trend and variation of Arctic sea-ice extent during 1979-2012 from a latitude perspective of ice edge
No full textArctic sea-ice extent (in summer) has been shrinking since the 1970s. However, we have little knowledge of the detailed spatial variability of this shrinking. In this study, we examine the (latitudinal) ice extent along each degree of longitude, using the monthly Arctic ice index data sets (1979–2012) from the National Snow and Ice Data Center. Statistical analysis suggests that: (1) for summer months (July–October), there was a 34-year declining trend in sea-ice extent at most regions, except for the Canadian Arctic Archipelago, Greenland and Svalbard, with retreat rates of 0.0562–0.0898 latitude degree/year (or 6.26–10.00 km/year, at a significance level of 0.05); (2) for sea ice not geographically muted by the continental coastline in winter months (January–April), there was a declining trend of 0.0216–0.0559 latitude degree/year (2.40–6.22 km/year, at a significance level of 0.05). Regionally, the most evident sea-ice decline occurred in the Chukchi Sea from August to October, Baffin Bay and Greenland Sea from January to May, Barents Sea in most months, Kara Sea from July to August and Laptev Sea and eastern Siberian Sea in August and September. Trend analysis also indicates that: (1) the decline in summer ice extent became significant (at a 0.05 significance level) since 1999 and (2) winter ice extent showed a clear changing point (decline) around 2000, becoming statistically significant around 2005. The Pacific–Siberian sector of the Arctic accounted for most of the summer sea-ice decline, while the winter recovery of sea ice in the Atlantic sector tended to decrease.Keywords: NSIDC ice index; Arctic; sea-ice extent; ice-edge latitude.(Published: 11 September 2014)Citation: Polar Research 2014, 33, 21249, http://dx.doi.org/10.3402/polar.v33.2124
Variability of humidity conditions in the Arctic during the first International Polar Year, 1882-83
No full textOf all the early instrumental data for the Arctic, the meteorological data gathered during the first International Polar Year, in 1882–83 (IPY-1), are the best in terms of coverage, quality and resolution. Research carried out during IPY-1 scientific expeditions brought a significant contribution to the development of hygrometry in polar regions at the end of the 19th century. The present paper gives a detailed analysis of a unique series of humidity measurements that were carried out during IPY-1 at hourly resolutions at nine meteorological stations, relatively evenly distributed in the High Arctic. It gives an overall view of the humidity conditions prevalent in the Arctic at that time. The results show that the spatial distribution of atmospheric water vapour pressure (e) and relative humidity (RH) in the Arctic during IPY-1 was similar to the present. In the annual course the highest values of e were noted in July and August, while the lowest occurred in the cold half of the year. In comparison to present-day conditions (1961–1990), the mean values of RH in the IPY-1 period (September 1882 to July 1883) were higher by 2.4–5.6%. Most of the changes observed between historical and modern RH values are not significant. The majority of historical daily RH values lie between a distance of less than two standard deviations from current long-term monthly means.To access the supplementary material for this article, please see Supplementary files in the column to the right (under Article Tools).Keywords: Humidity conditions; Arctic; early instrumental period; historical climatology(Published: 8 September 2014)Citation: Polar Research 2014, 33, 23896, http://dx.doi.org/10.3402/polar.v33.2389
Walruses recovering after 60+ years of protection in Svalbard, Norway
No full textWalruses were brought to the brink of extinction in Svalbard (Norway) during 350 years of unregulated harvesting. They became protected in 1952, when few remained. During the first 30 years of protection, approximately 100 animals became established within the archipelago, most of which likely came from Franz Josef Land, to the east. A marked recovery has taken place since then. This study reports the results of a photographic aerial survey flown in summer 2012, covering all current and historical haul-out sites for walruses in Svalbard. It provides updates regarding the increasing numbers of: (1) land-based haul-out sites (from 78 in 2006 to 91 in 2012); (2) occupied sites (from 17 in 2006 to 24 in the 2012 survey); (3) sites with mother–calf pairs (which increased from a single site with a single small calf in 2006 to 10 sites with a total of 57 small calves in 2012) and; (4) a 48% increase in abundance in the six-year period between the two surveys to 3886 (confidence interval 3553–4262) animals, including animals in the water at the time of the survey. Future environmental change might reduce benthic production in the Arctic, reducing the prey-base for walruses, and also impact walruses directly via declines in their sea-ice breeding habitat. But, currently the Svalbard walrus population is growing at a rate that matches the theoretical maximum rate of growth that has been calculated for recovering walrus populations under favourable environmental conditions with no food limitations.Keywords: Arctic; expansion; mother–calf distribution; pinniped; population trend.(Published: 7 October 2014)Citation: Polar Research 2014, 33, 26034, http://dx.doi.org/10.3402/polar.v33.2603
Three artotrogids (Crustacea: Copepoda: Siphonostomatoida) from the Ross Sea, Antarctica
No full textThe Artotrogidae, one of the most primitive of siphonostomatoid families, consists currently of 117 species in 21 genera. Most of these species (65%) are poorly or incompletely described since they have been rarely recorded in recent decades and, when encountered, have been found in very low numbers. During the 19th Italian Antarctic Expedition, with the RV Italica, to the Ross Sea in austral summer 2004, some artotrogid copepods were collected. This paper redescribes two species of artotrogid copepods, which are known only from the Southern Ocean, Neobradypontius neglectus and Cryptopontiuslatus, and describes for the first time a male of the genus Neobradypontius. Furthermore, a new species is described and added to Sestropontius, increasing the number of known species of this genus to three. The main discrepancies between the original descriptions and the specimens of the two species collected from the Ross Sea redescribed here were on the armature of the antennary exopod and leg 5. The new species, Sestropontius italicae, shares with its most similar congener, S. mckinnoni, the armature of the third endopodal segment of leg 1 and leg 2 and that of the third exopodal segment of leg 4. However, the segmentation of the antennae and the armature on the antennary exopod are different.Keywords: Antarctica; Artotrogidae; redescription; Neobradypontius; Sestropontius; CryptopontiusTo access larger versions of Figs. 2–12 please see the supplementary file in the column to the right (under Article Tools)(Published: 8 December 2014)Citation: Polar Research 2014, 33, 24135, http://dx.doi.org/10.3402/polar.v33.2413
Egg masses of the Patagonian squid (Doryteuthis Amerigo gahi) attached to giant kelp (Macrocystis pyrifera) in the sub-Antarctic ecoregion
No full textEgg masses of the Patagonian squid Doryteuthis (Amerigo) gahi attached to giant kelp (Macrocystis pyrifera) in the Magellanic channels of the sub-Antarctic ecoregion in southern South America is documented for the first time. Of seven egg masses observed between 2008 and 2011, one was taken to the laboratory to be analysed and photographed. Comprising long transparent capsules containing eggs, the masses were strongly attached to the stipes of M. pyrifera. This macroalgae is a potentially important economic resource due to its multiple industrial uses; this study shows that it also serves an important ecological role as a spawning substrate for D. gahi.Keywords: Doryteuthis; egg masses; giant kelp; Patagonian squid; sub-Antarctic ecoregion(Published: 5 November 2014)Citation: Polar Research 2014, 33, 21636, http://dx.doi.org/10.3402/polar.v33.2163