Modelling snow ice and superimposed ice on landfast sea ice in Kongsfjorden, Svalbard

Caixin Wang,

Bin Cheng,

Keguang Wang,

Sebastian Gerland,

Olga Pavlova

Опубликована Авг. 24, 2015

Snow ice and superimposed ice formation on landfast sea ice in a Svalbard fjord, Kongsfjorden, was investigated with a high-resolution thermodynamic snow and sea-ice model, applying meteorological weather station data as external forcing. The model shows that sea-ice formation occurs both at the ice bottom and at the snow/ice interface. Modelling results indicated that the total snow ice and superimposed ice, which formed at the snow/ice interface, was about 14 cm during the simulation period, accounting for about 15% of the total ice mass and 35% of the total ice growth. Introducing a time-dependent snow density improved the modelled results, …

The significant inputs of trace elements and rare earth elements from melting glaciers in Antarctic coastal waters

Intae Kim,

Guebuem Kim,

Eun Jung Choy

Опубликована Май 7, 2015

To evaluate the impact of modern glacier melting on the chemical enrichment of Antarctic coastal waters, we measured trace elements, including dissolved iron (Fe) and rare earth elements (REEs), together with dissolved inorganic nitrogen, phosphorous, silicate and dissolved organic carbon (DOC) in ice, snow and coastal seawater of Marian Cove in the northernmost part of Antarctica (62°S). There was an increase in the concentrations of Fe and other trace elements (Al, Mn, Cr, Ni, Co, Pb and REEs) between the bay mouth and the glacier valleys. Good correlations between salinity and these chemical elements indicate that the trend was mainly …

Assessing regional populations of ground-nesting marine birds in the Canadian High Arctic

Mark Maftei,

Shanti E. Davis,

Mark L. Mallory

Опубликована Апрель 7, 2015

The Queens Channel region of Nunavut is an ecologically distinct area within the Canadian High Arctic consisting of an extensive archipelago of small, low-lying gravel islands throughout which form several localized but highly productive polynyas. We used aerial survey and colony-monitoring data to assess regional- and colony-level fluctuations in the number of birds in this region between 2002 and 2013. Regional and colony-specific monitoring suggested that common eider (Somateria mollissima) numbers are increasing, while numbers of Arctic terns (Sterna paradisaea) may be in decline. Based on these data, we suggest that even infrequent comprehensive surveys are more useful than annual …

Foraging ecology of ringed seals (Pusa hispida), beluga whales (Delphinapterus leucas) and narwhals (Monodon monoceros) in the Canadian High Arctic determined by stomach content and stable isotope analysis

Jordan K. Matley,

Terry A. Dick,

Aaron T. Fisk

Опубликована Май 18, 2015

Stomach content and stable isotope analysis (δ13C and δ15N from liver and muscle) were used to identify habitat and seasonal prey selection by ringed seals (Pusa hispida; n=21), beluga whales (Delphinapterus leucas; n=13) and narwhals (Monodon monoceros; n=3) in the eastern Canadian Arctic. Arctic cod (Boreogadus saida) was the main prey item of all three species. Diet reconstruction from otoliths and stable isotope analysis revealed that while ringed seal size influenced prey selection patterns, it was variable. Prey-size selection and on-site observations found that ringed seals foraged on smaller, non-schooling cod whereas belugas and narwhals consumed larger individuals in schools. …

Observing the Arctic Ocean carbon cycle in a changing environment

Leif G. Anderson,

Robie W. Macdonald

Опубликована Дек. 10, 2015

Climate warming is especially pronounced in the Arctic, which has led to decreased sea-ice coverage and substantial permafrost thawing. These changes have a profound impact on the carbon cycle that directly affects the air–sea exchange of carbon dioxide (CO2), possibly leading to substantial feedback on atmospheric CO2 concentration. Several recent studies have indicated such feedback but the future quantitative impact is very uncertain. To minimize these uncertainties, there is a need for extensive field studies in order to achieve both a better process understanding as well as to detect probable trends in these processes. In this contribution, we describe a …

Patterns and trends of macrobenthic abundance, biomass and production in the deep Arctic Ocean

Renate Degen,

Antje Boetius,

Thomas Brey,

Andrey Vedenin,

Manuela Gusky

Опубликована Авг. 26, 2015

Little is known about the distribution and dynamics of macrobenthic communities of the deep Arctic Ocean. The few previous studies report low standing stocks and confirm a gradient with declining biomass from the slopes down to the basins, as commonly reported for deep-sea benthos. In this study, we investigated regional differences of faunal abundance and biomass, and made for the first time ever estimates of deep Arctic community production by using a multi-parameter artificial neural network model. The underlying data set combines data from recent field studies with published and unpublished data from the past 20 years, to analyse the …

Application of remotely piloted aircraft systems in observing the atmospheric boundary layer over Antarctic sea ice in winter

Marius O. Jonassen,

Andreas Scholtz,

Timo Vihma,

Astrid Lampert,

Gert König-Langlo,

Christof Lüpkes,

Priit Tisler,

Barbara Altstädter

Опубликована Окт. 8, 2015

The main aim of this paper is to explore the potential of combining measurements from fixed- and rotary-wing remotely piloted aircraft systems (RPAS) to complement data sets from radio soundings as well as ship and sea-ice-based instrumentation for atmospheric boundary layer (ABL) profiling. This study represents a proof-of-concept of RPAS observations in the Antarctic sea-ice zone. We present first results from the RV Polarstern Antarctic winter expedition in the Weddell Sea in June–August 2013, during which three RPAS were operated to measure temperature, humidity and wind; a fixed-wing small unmanned meteorological observer (SUMO), a fixed-wing meteorological mini-aerial vehicle, and an …

Mapping lichen distribution on the Antarctic Peninsula using remote sensing, lichen spectra and photographic documentation by citizen scientists

Paula Casanovas,

Martin Black,

Peter Fretwell,

Peter Convey

Опубликована Дек. 26, 2015

On the Antarctic Peninsula, lichens are the most diverse botanical component of the terrestrial ecosystem. However, detailed information on the distribution of lichens on the Antarctic Peninsula region is scarce, and the data available exhibit significant heterogeneity in sampling frequency and effort. Satellite remote sensing, in particular the use of the Normalized Difference Vegetation Index (NDVI), has facilitated determination of vegetation richness and cover distribution in some remote and otherwise inaccessible environments. However, it is known that using NDVI for the detection of vegetation can overlook the presence of lichens even if their land cover is extensive. We tested the …

Ice - ocean coupled computations for sea-ice prediction to support ice navigation in Arctic sea routes

Liyanarachchi Waruna Arampath De Silva,

Hajime Yamaguchi,

Jun Ono

Опубликована Ноя. 23, 2015

With the recent rapid decrease in summer sea ice in the Arctic Ocean extending the navigation period in the Arctic sea routes (ASR), the precise prediction of ice distribution is crucial for safe and efficient navigation in the Arctic Ocean. In general, however, most of the available numerical models have exhibited significant uncertainties in short-term and narrow-area predictions, especially in marginal ice zones such as the ASR. In this study, we predict short-term sea-ice conditions in the ASR by using a mesoscale eddy-resolving ice–ocean coupled model that explicitly treats ice floe collisions in marginal ice zones. First, numerical issues associated …

Arctic climate change in an ensemble of regional CORDEX simulations

Torben Koenigk,

Peter Berg,

Ralf Döscher

Опубликована Март 9, 2015

Fifth phase Climate Model Intercomparison Project historical and scenario simulations from four global climate models (GCMs) using the Representative Concentration Pathways greenhouse gas concentration trajectories RCP4.5 and RCP8.5 are downscaled over the Arctic with the regional Rossby Centre Atmosphere model (RCA). The regional model simulations largely reflect the circulation bias patterns of the driving global models in the historical period, indicating the importance of lateral and lower boundary conditions. However, local differences occur as a reduced winter 2-m air temperature bias over the Arctic Ocean and increased cold biases over land areas in RCA. The projected changes are dominated by …

The role of atmospheric precipitation in introducing contaminants to the surface waters of the Fuglebekken catchment, Spitsbergen

Katarzyna Kozak,

Krystyna Kozioł,

Bartłomiej Luks,

Stanisław Chmiel,

Marek Ruman,

Mariusz Marć,

Jacek Namieśnik,

Żaneta Polkowska

Опубликована Ноя. 23, 2015

Although the Svalbard Archipelago is located at a high latitude, far from potential contaminant sources, it is not free from anthropogenic impact. Towards the Fuglebekken catchment, in the southern part of Spitsbergen, north of Hornsund fjord, contaminants can be transported from mainland pollution sources. In the precipitation and surface water collected in the catchment, the following elements were detected and quantified: Ag, Al, As, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Cs, Mo, Ni, Pb, Sb, Se, Sr, Tl, U, V and Zn. Additionally, pH, electrical conductivity and total organic carbon (TOC) were determined in those samples. The acidic …

Variability in transport of terrigenous material on the shelves and the deep Arctic Ocean during the Holocene

Carolyn Wegner,

Katrina E. Bennett,

Anne de Vernal,

Matthias Forwick,

Michael Fritz,

Maija Heikkilä,

Hugues Lantuit,

Michał Laska,

Mateusz Moskalik,

Matt O'Regan,

Agnieszka Promińska,

Volker Rachold,

Jorien E. Vonk,

Magdalena Łacka,

Joanna Pawłowska,

Kirstin Werner

Опубликована Дек. 9, 2015

Arctic coastal zones serve as a sensitive filter for terrigenous matter input onto the shelves via river discharge and coastal erosion. This material is further distributed across the Arctic by ocean currents and sea ice. The coastal regions are particularly vulnerable to changes related to recent climate change. We compiled a pan-Arctic review that looks into the changing Holocene sources, transport processes and sinks of terrigenous sediment in the Arctic Ocean. Existing palaeoceanographic studies demonstrate how climate warming and the disappearance of ice sheets during the early Holocene initiated eustatic sea-level rise that greatly modified the physiography of the Arctic …

Summertime plankton ecology in Fram Strait - a compilation of long- and short-term observations

Eva-Maria Nöthig,

Astrid Bracher,

Anja Engel,

Katja Metfies,

Barbara Niehoff,

Ilka Peeken,

Eduard Bauerfeind,

Alexandra Cherkasheva,

Steffi Gäbler-Schwarz,

Kristin Hardge,

Estelle Kilias,

Angelina Kraft,

Yohannes Mebrahtom Kidane,

Catherine Lalande,

Judith Piontek,

Karolin Thomisch,

Mascha Wurst

Опубликована Дек. 1, 2015

Between Greenland and Spitsbergen, Fram Strait is a region where cold ice-covered Polar Water exits the Arctic Ocean with the East Greenland Current (EGC) and warm Atlantic Water enters the Arctic Ocean with the West Spitsbergen Current (WSC). In this compilation, we present two different data sets from plankton ecological observations in Fram Strait: (1) long-term measurements of satellite-derived (1998–2012) and in situ chlorophyll a (chl a) measurements (mainly summer cruises, 1991–2012) plus protist compositions (a station in WSC, eight summer cruises, 1998–2011); and (2) short-term measurements of a multidisciplinary approach that includes traditional plankton investigations, remote sensing, zooplankton, microbiological …

On-site and in situ remediation technologies applicable to petroleum hydrocarbon contaminated sites in the Antarctic and Arctic

Danielle Camenzuli,

Benjamin L. Freidman

Опубликована Сен. 7, 2015

Petroleum hydrocarbon contaminated sites, associated with the contemporary and legacy effects of human activities, remain a serious environmental problem in the Antarctic and Arctic. The management of contaminated sites in these regions is often confounded by the logistical, environmental, legislative and financial challenges associated with operating in polar environments. In response to the need for efficient and safe methods for managing contaminated sites, several technologies have been adapted for on-site or in situ application in these regions. This article reviews six technologies which are currently being adapted or developed for the remediation of petroleum hydrocarbon contaminated sites in the Antarctic …

Status and trends in the structure of Arctic benthic food webs

Monika Ke ̨dra,

Charlotte Moritz,

Emily S. Choy,

Carmen David,

Renate Degen,

Steven Duerksen,

Ingrid Ellingsen,

Barbara Górska,

Jacqueline M. Grebmeier,

Dubrava Kirievskaya,

Dick van Oevelen,

Kasia Piwosz,

Annette Samuelsen,

Jan Marcin Węsławski

Опубликована Май 20, 2015

Ongoing climate warming is causing a dramatic loss of sea ice in the Arctic Ocean, and it is projected that the Arctic Ocean will become seasonally ice-free by 2040. Many studies of local Arctic food webs now exist, and with this review paper we aim to synthesize these into a large-scale assessment of the current status of knowledge on the structure of various Arctic marine food webs and their response to climate change, and to sea-ice retreat in particular. Key drivers of ecosystem change and potential consequences for ecosystem functioning and Arctic marine food webs are identified along the sea-ice …

Regional passive seismic monitoring reveals dynamic glacier activity on Spitsbergen, Svalbard

Andreas Köhler,

Christian Weidle,

Steven J. Gibbons,

Christopher Nuth,

Johannes Schweitzer

Опубликована Дек. 4, 2015

Dynamic glacier activity is increasingly observed through passive seismic monitoring. We analysed near-regional-scale seismicity on the Arctic archipelago of Svalbard to identify seismic icequake signals and to study their spatial–temporal distribution within the 14-year period from 2000 until 2013. This is the first study that uses seismic data recorded on permanent broadband stations to detect and locate icequakes in different regions of Spitsbergen, the main island of the archipelago. A temporary local seismic network and direct observations of glacier calving and surging were used to identify icequake sources. We observed a high number of icequakes with clear spectral peaks between …