Distribution and reproduction of the Arctic ctenophore Mertensia ovum in the Baltic Sea

AbstractThe storm events in the Baltic Sea are examined in connection with the main weather patterns grouped into the circulation types (CTs), and their changes in present climate. A calendar of storms was derived from results of wave model SWAN (Simulating WAves Nearshore) experiments for 1948-2011. Based on this calendar, a catalogue of atmospheric sea level pressure (SLP) fields was prepared for CTs from the NCEP/NCAR dataset. SLP fields were then analyzed using a pattern recognition algorithm which employed empirical orthogonal decomposition and cluster analysis. For every CT we conducted an analysis of their seasonal and interannual changes, along with their role in storm event formation. An increase of the storm CTs’ frequency in the second part of the 20th century was shown to be in a close agreement with teleconnection circulation patterns such as the Arctic Oscillation, North Atlantic Oscillation and the Scandinavian blocking.

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Zoologisch-botanische Exkursionen an das Weiße Meer – seine Fischgemeinschaft und historische Verbindungen zur Ostsee

Archiv Natur- und Landeskunde Mecklenburg-Vorpommern ◽

10.30819/anlk.58.11 ◽

2021 ◽

Vol 58 ◽

pp. 131-145

Author(s):

Helmut M. Winkler

Keyword(s):

Baltic Sea ◽

Fish Species ◽

Fish Community ◽

White Sea ◽

The Arctic ◽

The White Sea ◽

The Baltic Sea ◽

Marginal Sea ◽

Glacial Relicts ◽

The Baltic

Ragnar Kinzelbach hat das langjährige Projekt der zoologisch-botanischen Austauschpraktika der Moskauer und der Rostocker Universität mit der ihm eigenen Vehemenz tatkräftig unterstützt und begleitet. Zweimal nahm er am Feldpraktikum in Russland am Weißen Meer teil. In diesem Beitrag wird dieses Randmeer vorgestellt und mit der Ostsee verglichen, einschließlich der postglazialen Entwicklung. Ein bis heute noch nicht endgültig entschiedenes Thema ist die Diskussion um Glazialrelikte der Ostseefauna, die zum Teil mit dem Weißen Meer in Verbindung stehen. Es wird eine Übersicht der Fischgemeinschaft des bis in die Arktis reichenden Weißen Meeres gegeben und auf Besonderheiten verwiesen. Mit weniger als 50 marinen Fischarten, von denen nur 32 etabliert sind, ist es sehr artenarm. 23 Fischarten konnten als Belege für die Zoologische Sammlung der Rostocker Universität gesammelt werden. Zoological and botanical excursions to the White Sea – its fish community and historical connections to the Baltic Sea Abstract: With his characteristic vehemence, Ragnar Kinzelbach actively supported and accompanied the longstanding zoological-botanical students exchange project between the universities of Moscow and Rostock. Twice he participated in the field courses in Russia at the White Sea. This paper presents this marginal sea in comparison with the Baltic Sea, including the postglacial development. A topic that has not yet been conclusively resolved is the discussion of glacial relicts of the Baltic fauna, some of which are associated with the White Sea. An overview of the fish community of the White Sea, which extends into the Arctic, is given and special features are pointed out. It is a very species-poor sea, with fewer than 50 marine fish species, of which only 32 are established. 23 fish species were collected for the zoological collection of the Rostock University

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Feeding of the Arctic ctenophore Mertensia ovum in the Baltic Sea: evidence of the use of microbial prey

Journal of Plankton Research ◽

10.1093/plankt/fbt101 ◽

2013 ◽

Vol 36 (1) ◽

pp. 91-103 ◽

Cited By ~ 4

Author(s):

Sanna Majaneva ◽

Outi Setälä ◽

Elena Gorokhova ◽

Maiju Lehtiniemi

Keyword(s):

Baltic Sea ◽

The Arctic ◽

The Baltic Sea ◽

The Baltic

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Multidecadal dynamics of the Arctic copepod Limnocalanus macrurus in relation to environmental variability in the Baltic Sea

ICES Journal of Marine Science ◽

10.1093/icesjms/fsz101 ◽

2019 ◽

Vol 76 (7) ◽

pp. 2427-2436 ◽

Cited By ~ 1

Author(s):

Heli Einberg ◽

Riina Klais ◽

Gunta Rubene ◽

Georgs Kornilovs ◽

Ivars Putnis ◽

...

Keyword(s):

Baltic Sea ◽

Water Temperature ◽

Environmental Variability ◽

The Arctic ◽

The Baltic Sea ◽

Bottom Water Temperature ◽

Limnocalanus Macrurus ◽

The Baltic ◽

Winter Severity

Abstract The Arctic Limnocalanus macrurus is a prominent representative of large copepods which performs several essential functions in freshwater and marine ecosystems. Being a cold stenotherm species, its distribution is primarily confined to deeper water layers. Based on the long-term observations from one of the largest spatially confined natural populations of this species in the Baltic Sea, we detected profound long-term variability of L. macrurus during 1958–2016: high abundances before the 1980s, then nearly disappearance in the 1990s and recovery in the 2000s. The main environmental parameters explaining the interannual variability of L. macrurus in spring were herring spawning stock biomass in preceding year, winter severity, and bottom water temperature in preceding summer. The effect of winter severity and water temperature was also non-linear. The sliding window correlation analysis pointed to a non-stationary relationship between the abundance of L. macrurus and the key variables. Given the observed pronounced seasonality in the population structure of L. macrurus (young stages dominated in the beginning of the year and only adults were left in the population in summer and autumn) we identified the dynamics of key environmental variables to understand this species under different ecosystem configurations and different combinations of drivers of change.

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Species identification based on a semi-diagnostic marker: Evaluation of a simple conchological test for distinguishing blue mussels Mytilus edulis L. and M. trossulus Gould

PLoS ONE ◽

10.1371/journal.pone.0249587 ◽

2021 ◽

Vol 16 (7) ◽

pp. e0249587

Author(s):

Vadim Khaitov ◽

Julia Marchenko ◽

Marina Katolikova ◽

Risto Väinölä ◽

Sarah E. Kingston ◽

...

Keyword(s):

Baltic Sea ◽

Mytilus Edulis ◽

Species Identification ◽

Barents Sea ◽

White Sea ◽

The Arctic ◽

The White Sea ◽

The Baltic Sea ◽

Blue Mussels ◽

The Baltic

Cryptic and hybridizing species may lack diagnostic taxonomic characters leaving researchers with semi-diagnostic ones. Identification based on such characters is probabilistic, the probability of correct identification depending on the species composition in a mixed population. Here we test the possibilities of applying a semi-diagnostic conchological character for distinguishing two cryptic species of blue mussels, Mytilus edulis and M. trossulus. These ecologically, stratigraphically and economically important molluscs co-occur and hybridize in many areas of the North Atlantic and the neighboring Arctic. Any cues for distinguishing them in sympatry without genotyping would save much research effort. Recently these species have been shown to statistically differ in the White Sea, where a simple character of the shell was used to distinguish two mussel morphotypes. In this paper, we analyzed the associations between morphotypes and species-specific genotypes based on an abundant material from the waters of the Kola Peninsula (White Sea, Barents Sea) and a more limited material from Norway, the Baltic Sea, Scotland and the Gulf of Maine. The performance of the “morphotype test” for species identification was formally evaluated using approaches from evidence-based medicine. Interspecific differences in the morphotype frequencies were ubiquitous and unidirectional, but their scale varied geographically (from 75% in the White Sea to 15% in the Baltic Sea). In addition, salinity-related variation of this character within M. edulis was revealed in the Arctic Barents Sea. For every studied region, we established relationships between the proportions of the morphotypes in the populations as well as between the proportions of the morphotypes in samples and the probabilities of mussels of different morphotypes being M. trossulus and M. edulis. We provide recommendations for the application of the morphotype test to mussels from unstudied contact zones and note that they may apply equally well to other taxa identified by semi-diagnostic traits.

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Review of 'Atmospheric teleconnections between the Arctic and the Baltic Sea regions' by Liisi Jakobson, Erko Jakobson, Piia Post, and Jaak Jaagus (esd-2017-37)

10.5194/esd-2017-37-rc3 ◽

2017 ◽

Author(s):

Anonymous

Keyword(s):

Baltic Sea ◽

The Arctic ◽

The Baltic Sea ◽

Atmospheric Teleconnections ◽

The Baltic

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Ship Based Measurements of Seasonal Atmospheric Mercury Concentrations over the Baltic Sea

10.20944/preprints201711.0159.v1 ◽

2017 ◽

Author(s):

Hanna Hoeglind ◽

Sofia Eriksson ◽

Katarina Gardfeldt

Keyword(s):

Baltic Sea ◽

Background Level ◽

Ambient Air ◽

Atmospheric Mercury ◽

Anthropogenic Sources ◽

The Arctic ◽

The Baltic Sea ◽

Back Trajectories ◽

Gaseous Mercury ◽

The Baltic

Mercury is a toxic pollutant emitted from both natural sources and through human activities. A global interest in atmospheric mercury has risen ever since the discovery of the Minamata disease in 1956. Properties of gaseous elemental mercury enable long range transport which can cause pollution even in pristine environments. Total gaseous mercury (TGM) was measured from winter 2016 to spring 2017 over the Baltic Sea. A Tekran 2357A mercury analyser was installed aboard the research and icebreaking vessel Oden for the purpose of continuous measurements of gaseous mercury in ambient air. Measurements were performed during a campaign along the Swedish east coast and in the Bothnian Bay near Lulea during the icebreaking season. Data was evaluated from Gothenburg using a plotting software and back trajectories for air masses were calculated. The TGM average of 1.365 ± 0.054 ng/m3 during winter and 1.288 ± 0.140 ng/m3 during spring was calculated as well as a total average of 1.362 ± 0.158 ng/m3. Back trajectories showed a possible correlation of anthropogenic sources elevating the mercury background level in some areas. There were also indications of depleted air, i.e., air with lower concentrations than average, being transported from the Arctic to northern Sweden resulting in a drop in TGM levels.

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Estimation of degree of sea ice ridging based on dual-polarized C-band SAR data

The Cryosphere ◽

10.5194/tc-12-343-2018 ◽

2018 ◽

Vol 12 (1) ◽

pp. 343-364 ◽

Cited By ~ 12

Author(s):

Alexandru Gegiuc ◽

Markku Similä ◽

Juha Karvonen ◽

Mikko Lensu ◽

Marko Mäkynen ◽

...

Keyword(s):

Sea Ice ◽

Baltic Sea ◽

Arctic Ocean ◽

Texture Features ◽

The Arctic ◽

The Baltic Sea ◽

Essential Information ◽

Ice Concentration ◽

Dual Polarized ◽

The Baltic

Abstract. For ship navigation in the Baltic Sea ice, parameters such as ice edge, ice concentration, ice thickness and degree of ridging are usually reported daily in manually prepared ice charts. These charts provide icebreakers with essential information for route optimization and fuel calculations. However, manual ice charting requires long analysis times, and detailed analysis of large areas (e.g. Arctic Ocean) is not feasible. Here, we propose a method for automatic estimation of the degree of ice ridging in the Baltic Sea region, based on RADARSAT-2 C-band dual-polarized (HH/HV channels) SAR texture features and sea ice concentration information extracted from Finnish ice charts. The SAR images were first segmented and then several texture features were extracted for each segment. Using the random forest method, we classified them into four classes of ridging intensity and compared them to the reference data extracted from the digitized ice charts. The overall agreement between the ice-chart-based degree of ice ridging and the automated results varied monthly, being 83, 63 and 81 % in January, February and March 2013, respectively. The correspondence between the degree of ice ridging reported in the ice charts and the actual ridge density was validated with data collected during a field campaign in March 2011. In principle the method can be applied to the seasonal sea ice regime in the Arctic Ocean.

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Atmospheric teleconnections between the Arctic and the Baltic Sea regions

10.5194/esd-2017-37 ◽

2017 ◽

Author(s):

Liisi Jakobson ◽

Erko Jakobson ◽

Piia Post ◽

Jaak Jaagus

Keyword(s):

Baltic Sea ◽

Reanalysis Data ◽

Specific Humidity ◽

The Arctic ◽

The Baltic Sea ◽

Sea Ice Concentration ◽

Strong Negative Correlation ◽

Baffin Bay ◽

Baltic Sea Region ◽

The Baltic

Abstract. The teleconnections between meteorological parameters of the Arctic and the Baltic Sea regions were analysed based on the NCEP-CFSR reanalysis data for 1979–2015. The Baltic Sea region was characterised by meteorological values at a testing point (TP) in Southern Estonia (58 N, 26 E). Temperature and specific humidity at the 1000 hPa level at the TP have a strong negative correlation with the Greenland region during all seasons except summer. The strongest teleconnections between the same parameter at the Baltic Sea region and the Arctic are found in winter, but they are clearly affected by the Arctic Oscillation (AO) index. After removal of the AO index variability, correlations in winter were below ±0.5, while in other seasons there remained regions with strong (|R| > 0.5) correlations. Strong correlations are present between different climate variables at the TP and the Arctic. Temperature and wind speed at the 1000 hPa level in the Baltic Sea region have a significant positive correlation with sea ice concentration in Baffin Bay and in regions between the North Pole and Greenland during all seasons except summer. These teleconnections cannot be explained with the AO index variability. The most permanent lagged correlations in 1000 hPa temperature are in summer at the TP with the Baffin Bay region in the previous spring, winter and even autumn. At every season there are some regions in the Arctic that has strong teleconnections (|R| > 0.5, p

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