1,721,047 research outputs found
Biopolymers form a gelatinous microlayer at the air-sea interface when Arctic sea ice melts
Get PDFThe interface layer between ocean and atmosphere is only a couple of micrometers thick but plays
a critical role in climate relevant processes, including the air-sea exchange of gas and heat and the
emission of primary organic aerosols (POA). Recent findings suggest that low-level cloud formation
above the Arctic Ocean may be linked to organic polymers produced by marine microorganisms. Sea
ice harbors high amounts of polymeric substances that are produced by cells growing within the seaice
brine. Here, we report from a research cruise to the central Arctic Ocean in 2012. Our study shows
that microbial polymers accumulate at the air-sea interface when the sea ice melts. Proteinaceous
compounds represented the major fraction of polymers supporting the formation of a gelatinous
interface microlayer and providing a hitherto unrecognized potential source of marine POA. Our study
indicates a novel link between sea ice-ocean and atmosphere that may be sensitive to climate change
Master track of ELISABETH MANN BORGESE cruise EMB369 in 1 sec resolution (zipped, 51 MB)
No full textRaw data acquired by position sensors on board RV Elisabeth Mann Borgese during expedition EMB369 were processed to receive a validated master track which can be used as reference of further expedition data. During EMB369 data from the motion reference unit exail Phins Gen.3, the Trimble SPS356 GPS receiver, the Furuno GP-170 and the Furuno GP-150 GPS receiver were used to calculate the mastertrack. Data were downloaded from DAVIS SHIP data base (https://dship.bsh.de) with a resolution of 1 sec. Processing and evaluation of the data is outlined in the data processing report. Processed data are provided as a master track with 1 sec resolution derived from the position sensors' data selected by priority and a generalized track with a reduced set of the most significant positions of the master track
Master track of ELISABETH MANN BORGESE cruise EMB369 in 1 sec resolution (zipped, 51 MB)
No full textRaw data acquired by position sensors on board RV Elisabeth Mann Borgese during expedition EMB369 were processed to receive a validated master track which can be used as reference of further expedition data. During EMB369 data from the motion reference unit exail Phins Gen.3, the Trimble SPS356 GPS receiver, the Furuno GP-170 and the Furuno GP-150 GPS receiver were used to calculate the mastertrack. Data were downloaded from DAVIS SHIP data base (https://dship.bsh.de) with a resolution of 1 sec. Processing and evaluation of the data is outlined in the data processing report. Processed data are provided as a master track with 1 sec resolution derived from the position sensors' data selected by priority and a generalized track with a reduced set of the most significant positions of the master track
Master tracks in different resolutions of ELISABETH MANN BORGESE cruise EMB369, Rostock - Rostock, 2025-06-23 - 2025-07-07
No full textRaw data acquired by position sensors on board RV Elisabeth Mann Borgese during expedition EMB369 were processed to receive a validated master track which can be used as reference of further expedition data. During EMB369 data from the motion reference unit exail Phins Gen.3, the Trimble SPS356 GPS receiver, the Furuno GP-170 and the Furuno GP-150 GPS receiver were used to calculate the mastertrack. Data were downloaded from DAVIS SHIP data base (https://dship.bsh.de) with a resolution of 1 sec. Processing and evaluation of the data is outlined in the data processing report. Processed data are provided as a master track with 1 sec resolution derived from the position sensors' data selected by priority and a generalized track with a reduced set of the most significant positions of the master track
Master tracks in different resolutions of ELISABETH MANN BORGESE cruise EMB369, Rostock - Rostock, 2025-06-23 - 2025-07-07
No full textRaw data acquired by position sensors on board RV Elisabeth Mann Borgese during expedition EMB369 were processed to receive a validated master track which can be used as reference of further expedition data. During EMB369 data from the motion reference unit exail Phins Gen.3, the Trimble SPS356 GPS receiver, the Furuno GP-170 and the Furuno GP-150 GPS receiver were used to calculate the mastertrack. Data were downloaded from DAVIS SHIP data base (https://dship.bsh.de) with a resolution of 1 sec. Processing and evaluation of the data is outlined in the data processing report. Processed data are provided as a master track with 1 sec resolution derived from the position sensors' data selected by priority and a generalized track with a reduced set of the most significant positions of the master track
Organic matter composition and heterotrophic bacterial activity at declining summer sea ice in the central Arctic Ocean
Get PDFThe Arctic Ocean is highly susceptible to climate change as evidenced by rapid warming and the drastic loss of sea ice during summer. The consequences of these environmental changes for the microbial cycling of organic matter are largely unexplored. Here, we investigated the distribution and composition of dissolved organic matter (DOM) along with heterotrophic bacterial activity in seawater and sea ice of the Eurasian Basin at the time of the record ice minimum in 2012. Bacteria in seawater were highly responsive to fresh organic matter and remineralized on average 55% of primary production in the upper mixed layer. Correlation analysis showed that the accumulation of dissolved combined carbohydrates (DCCHO) and dissolved amino acids (DAA), two major components of fresh organic matter, was related to the drawdown of nitrate. Nitrate‐depleted surface waters at stations adjacent to the Laptev Sea showed about 25% higher concentrations of DAA than stations adjacent to the Barents Sea and in the central Arctic basin. Carbohydrate concentration was the best predictor of heterotrophic bacterial activity in sea ice. In contrast, variability in sea‐ice bacterial biomass was largely driven by differences in ice thickness. This decoupling of bacterial biomass and activity may mitigate the negative effects of biomass loss due to ice melting on heterotrophic bacterial functions. Overall, our results reveal that changes in DOM production and inventories induced by sea‐ice loss have a high potential to enhance the bacterial remineralization of organic matter in seawater and sea ice of the Arctic Ocean
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Benthic Biodiversity from Microbes to Multicellular Organisms and Its Functional Interplays
No full textThis Special Issue explores the assessment of benthic biodiversity, spanning microbes, protists, megafauna, and fish, and its responses to both natural and human-induced drivers. It emphasizes how these communities influence key ecosystem functions such as biogeochemical fluxes and material transport across the seafloor. Despite advances in marine ecology, much of the benthic realm—particularly beyond macrofauna—remains poorly understood. By bringing together observational, experimental, and modeling approaches, this collection provides new insights into the complex dynamics of benthic communities and their reactions to environmental gradients and anthropogenic pressures
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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