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1

Synoptic conditions governing upwelling along the Polish Baltic coast

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Bednorz E. , Półrolniczak M. , Czernecki B.

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tom No. 55 (4)

767--785

EN

The study analyses atmospheric feedback to the occurrence of upwelling along the Polish Baltic coast. Upwelling events were identified on the basis of daily mean sea surface temperature (SST) maps from the period 1982-2010 derived from the NOAA OI SST V2 High Resolution Dataset. Synoptic conditions favourable to the occurrence of upwelling were determined on the basis of the NCEP/NCAR reanalysis data. On average, there are approximately 23 days with upwelling each year along the Polish Baltic coast, which account for approximately 13% of the warm period (April-September). The pressure pattern with an anticyclone centred over Scandinavia and extending over northern Europe induces a north-easterly flow of air along the Polish Baltic coast, which causes upwelling. Such a circulation pattern is accompanied by positive air temperature anomalies. The opposite pressure conditions, during which a trough of low pressure encompasses Scandinavia, cause a westerly flow over the southern part of the Baltic basin, which effectively inhibits upwelling along the Polish Baltic coast.

2

A statistical approach to coastal upwelling in the Baltic Sea based on the analysis of satellite data for 1990-2009

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Lehmann A. , Myrberg K. , Höflich K.

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tom No. 54 (3)

369-393

EN

A statistical analysis of Baltic Sea upwelling has been carried out to cover, for the first time, the entire sea area for the period 1990-2009. Weekly composite SST maps based on NOAA/AVHRR satellite data were used to evaluate the location and frequency of upwelling. The results obtained were analysed and compared with earlier studies with excellent agreement. Our study enables the most intense upwelling areas in the entire Baltic Sea to be evaluated. According to the analysis of 443 SST maps, the most common upwelling regions are found off the Swedish south and east coasts (frequency 10-25%), the Swedish coast of the Bothnian Bay (16%), the southern tip of Gotland (up to 15%), and the Finnish coast of the Gulf of Finland (up to 15%). Pronounced upwelling also occurs off the Estonian coast and the Baltic east coast (up to 15%), the Polish coast and the west coast of Rügen (10-15%); otherwise the upwelling frequency was between 5 and 10%. Additionally, simulated SST distributions derived from a Baltic Sea numerical model were analysed for the same period. Furthermore, at specific positions close to the coastline, surface winds based on the SMHI meteorological data base were analysed for the same 20-year period. Wind components parallel to the coast were discriminated into favourable and unfavourable winds forcing upwelling. The obtained frequencies of upwelling-favourable winds fit very well the observed upwelling frequencies derived from satellite SST maps. A positive trend of upwelling frequencies along the Swedish east coast and the Finnish coast of the Gulf of Finland was calculated for the period 1990-2009.

3

Response of eastern Indian Ocean (ODP Site 762B) benthic foraminiferal assemblages to the closure of the Indonesian seaway

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Rai A. K. , Singh W. B.

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tom No. 54 (3)

449-472

EN

Pliocene-Pleistocene deep sea benthic foraminifera from ODP Site 762B in the eastern Indian Ocean were examined to understand the tectonically/climatically induced palaeoceanographic changes. In addition to already published data on this site by Rai & Singh (2001), some more faunal parameters were considered in the present work. Characteristic benthic foraminiferal assemblages as well as more diverse fauna during the early Pliocene (before 3.5 Ma) reflected relatively oligotrophic and warm bottom water conditions. At the beginning of the late Pliocene (i.e. ~3 š 0.5 Ma) relative abundances of Uvigerina proboscidea, infaunal taxa and high productivity taxa increased, whereas faunal diversity showed a distinct decline, suggesting the development of pronounced upwelling resulting in higher surface water productivity. The strongly reduced inflow of warm and oligotrophic water masses as the South Equatorial Current (SEC) from the South Pacific to the eastern Indian Ocean due to the effective closure of the Indonesian seaway increased the surface water productivity. The closing of the Indonesian seaway during the late Pliocene was also responsible for the cessation of the warm, southward-flowing Leeuwin Current (LC) and the greater influence of the cold, deep and northward-flowing Western Australian Current (WAC) in the eastern Indian Ocean.

4

Wind-induced variability of hydrological parameters in the coastal zone of the southern Baltic Sea - a numerical study

88%

Jankowski A.

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tom Vol. 29, No. 3

5-34

EN

Abstract The wind-produced variability of temperature, salinity and velocity in the coastal zone of the southern Baltic Sea have been investigated with the help of a three-dimensional F-coordinate baroclinic model. The model was based on the Princeton Ocean Model code of Mellor (1993), known as POM. The main intention of this study was to reproduce the variability of the hydrological conditions as the response of stratified seawaters to the model atmospheric forcing of three successive storms. Winds of constant speed from eight directions over the Baltic during each storm were considered. The presentation of results is limited to the area along the Polish coasts of the Baltic Sea, where the complicated bottom topography exerts a crucial influence on water movements. The numerical model runs show that winds can play an important role in the water exchange between the coastal region and the open sea, generating intense fluctuations of hydrological parameters. When winds are from the SE, E and NE, coastal upwelling is frequent along the Polish Baltic coast (Bychkova and Victorov 1987, Bychkova et al. 1988, Urbanski 1993). The results calculated with the use of the POM code are in agreement with the results obtained using the z-level model (Krauss and Brügge 1991) and from studies in the Great Lakes and in other upwelling areas (Bennet 1974, Krauss 1979, Fennel 1986).

5

Response of coastal phytoplankton to upwelling induced hydrological changes in the Alappuzha mud bank region, southwest coast of India

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Madhu N. V. , Anil P. , Meenu P. , Gireeshkumar T. R. , Muraleedharan K. R. , Rehitha T. V. , Dayana M. , Vishal C. R.

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tom No. 63 (2)

261--275

EN

The response of phytoplankton community to the co-existing events of coastal upwelling and mud banks in the nearshore waters of Alappuzha (15 m depth), located in the southwest coast of India from April to November 2016, is described based on size-fractionated phytoplankton biomass (chlorophyll a), primary production and community composition. The study region exhibited well-distinct spatio-temporal hydrological changes because of the influence of wind-driven coastal upwelling, prevalent during the southwest monsoon (SWM) period. However, the formation of mud banks, in addition to coastal upwelling, was observed at station M2, which facilitated the substantial increase of water column turbidity and inorganic nutrients (ammonium, phosphate, and silicate) during and after the peak SWM period compared to the non-mud bank reference stations (M1 and M3). The prevailing hydrological changes were complemented the corresponding phytoplankton productivity patterns, in which profound domination of nanophytoplankton (2-20 µm) chlorophyll a and primary production was observed throughout the study region, irrespective of seasons. The SIMPER analysis, based on phytoplankton (mostly >20 µm) species composition data (microscopy), revealed the formation of certain characterizing species, mainly comprised of diatoms and dinoflagellates. The consistent predominance of the nanophytoplankton, established under variable hydrological scenarios, showed that the inorganic nutrient (specifically ammonium) availability was instrumental in defining the widespread growth of nanophytoplankton community compared to the prevailing light levels. The present study thus revealed that even the small-sized phytoplankton community could survive in the nutrient-enriched coastal waters, characterised by the co-existing upwelling and mud banks.

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Monitoring the effect of upwelling on the chlorophyll a distribution in the Gulf of Finland (Baltic Sea) using remote sensing and in situ data

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Uiboupin R. , Laanemets J. , Sipelgas L. , Raag L. , Lips I.

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tom No. 54 (3)

395-419

EN

The spatio-temporal variability of chlorophyl a (Chl a) caused by a sequence of upwelling events in the Gulf of Finland in July-August 2006 was studied using remote sensing data and field measurements. Spatial distributions of sea surface temperature (SST) and Chl a concentration were examined using MODIS and MERIS data respectively. The MERIS data were processed with an algorithm developed by the Free University of Berlin (FUB) for case 2 waters. Evaluation of MERIS Chl a versus in situ Chl a showed good correlation (r2 = 0.67), but the concentration was underestimated. The linear regression for a 2 h window was applied to calibrate MERIS Chl a. The spatio-temporal variability exhibited the clear influence of upwelling events and related filaments on Chl a distribution in the western and central Gulf. The lowest Chl a concentrations were recorded in the upwelled water, especially at the upwelling centres, and the highest concentrations (13 mg m-3) were observed about two weeks after the upwelling peak along the northern coast. The areas along the northern coast of upwelled water (4879 km2) on the SST map, and increased Chl a (5526 km2) two weeks later, were roughly coincident. The effect of upwelling events was weak in the eastern part of the Gulf, where Chl a concentration was relatively consistent throughout this period.

7

Upwelling characteristics in the Puck Bay [the Baltic Sea]

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Nowacki J. , Matciak M. , Szymelfenig M. , Kowalewski M.

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nr 2

3-16

8

Simulation of nutrient transport from different depths during an upwelling event in the Gulf of Finland

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Vali G. , Zhurbas V. , Laanemets J. , Elken J.

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nr (1-TI)

EN

Numerical simulation experiments with a high-resolution circulation model were carried out to study nutrient transport from different depths to the surface 10-m layer during an upwelling event along the northern coast of the Gulf of Finland in July 1999. The initial nutrient distribution is based on field measurements performed in the north-western part of the Gulf. Wind forcing covering the period of the upwelling along the northern coast was turned through 180◦ to simulate an upwelling along the southern coast. The simulation results showed that the main phosphorus transport to the upper 10-m layer occurred from depths shallower than 30 m for the upwelling events along both the northern and the southern coasts. Nitrogen transport to the upper 10-m layer was the largest from depths of 40–55 m for the upwelling along the northern and 40–65 m for the upwelling along the southern coast. Simulated cumulative volume transports to the upper 10-m layer from different depths showed that the contribution from deeper layers was larger in the case of the upwelling along the southern coast. The reduction of wind stress had a bigger influence on water transport from the deeper layers.

9

Środowiska sedymentacji ordowiku górnego w regionie kieleckim Gór Świętokrzyskich

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Trela W.

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tom nr 417

109-168

PL

W górnym ordowiku, w regionie kieleckim obserwowane są kontrasty facjalne związane z regionalną aktywnością tektoniczną i różnym tempem subsydencji basenu sedymentacyjnego. Efektem synsedymentacyjnych ruchów tektonicznych było powstanie pod koniec środkowego ordowiku wyniesienia podmorskiego, które w późnym ordowiku było miejscem rozwoju skondensowanych facji węglanowych - grejnstonów, pakstonów i wakstonów. W karadoku wyniesienie to graniczyło od południa z głębokim zbiornikiem, który był miejscem rozwoju facji ilastych. Okresowo sedymentacja w tym zbiorniku odbywała się w warunkach deficytu tlenowego wód dennych. Od późnego lanwirnu po początek późnego karadoku warunki ekologiczne i sedymentacyjne, na obszarze wyniesienia podmorskiego, były kształtowane przez prąd oceaniczny płynący między Avalonią a Baltiką, wzdłuż północnego brzegu bloku małopolskiego, oraz związane z nim prądy wstępujące. Zanik oddziaływania tego prądu był zbieżny ze zmianami cyrkulacji oceanicznej spowodowanej stopniowym zamykaniem w późnym ordowiku zachodniej części morza Tornquista, w wyniku dokowania wschodniej Avalonii do Baltiki oraz przesunięciem obu obszarów w kierunku niższej szerokości geograficznej. Abrazja tego wyniesienia przez falowanie sztormowe i oddziaływanie prądu oceanicznego oraz słabszy potencjał wzrostowy chłodnowodnego zespołu faunistycznego, spowodowały spowolnienie tempa depozycji, lub nawet jego okresowe zatrzymanie. Konsekwencją tego jest znaczna kondensacja osadu i rozwój małego "wygłodzonego wyniesienia podmorskiego" (statved seamount). Pod koniec wczesnego karadoku, w efekcie ożywienia regionalnej aktywności tektonicznej, nastąpiła przebudowa planu paleomorfologicznego. W centralnej części regionu kieleckiego ujawniły się tendencje do wzrostu pojemności akomodacyjnej, związane z tektonicznie uwarunkowanym większym tempem subsydencji tej części wyniesienia podmorskiego. Na przełomie karadoku i aszgilu zaznaczył się spadek względnego poziomu morza. Litologicznym wyrazem globalnej regresji w późnym aszgilu są w regionie kieleckim osady klastyczne (waki kwarcowe) związane z grawitacyjnymi spływami osadu, schodzącymi prawdopodobnie ze skłonu delty stożkowej. Utrzymująca się lokalnie w późnym aszgilu tendencja do pogłębiania basenu sedymentacyjnego centralnej części regionu kieleckiego sprzyjała natomiast zachowaniu ciągłości sedymentacyjnej między ordowikiem i sylurem.

EN

The spatial and temporal extent of the Upper Ordovician facies in the Kielce Region indicates regional tectonic controls on its distribution. The sedimentary basin was affected by differential subsidence rate, which probably originated from synsedimentary block faulting in the basement, that resulted in establishment of horst-like submarine palaeohigh with condensed carbonate deposition - grainstones, packstones to wackestons. During the Caradoc, the palaeohigh was bounded, to the south, by a deeper-water basin subjected to much stronger subsidence rate, where claystone facies were deposited. Periodically, the oxygen-deficient conditions occurred at the basin floor. From the latest Llanvirn to the early Late Caradoc the sedimentary and ecological conditions on the palaeohigh were affected by upwelling associated with the oceanic current that flowed south-eastwards along the northern margins of the Małopolska Block. The cessation of that oceanic current activity and then upwelling inflow was coeval with changes in palaeooceanographic circulation related to gradual closare of the western part of the Tornquist Sea during the latest Ordovician due to collision of the Avalonia with Baltica. The hydrodynamic conditions on the palaeohigh were dominated by interaction of storms and the oceanic palaeocurrent that together with slow carbonate production, resulted in low accumulation rate and subsequently in development of small starved seamount with a condensed carbonate sediment. During the end of the early Caradoc there was a rearrangement of the palaeohigh that resulted in establishment of a deeper water basin in the central part of the Kielce Region, with a continuous sedimentation in some places across the Silurian-Ordovician boundary. During the latest Caradoc and earliest Ashgill, the tectonic activity was intensified in the central part of the Kielce Region, resulting in uplifting of some parts of the basin floor, and subsequently a juxtaposition of the shallow and deep-water deposits in this area. The lithological expression of the Late Ashgill regression in the Kielce Region are clastic deposits (quartz wackes) accumulated by sandy debris flow derived from a fan delta.