Wyniki wyszukiwania - Biblioteka Nauki

Ten serwis zostanie wyłączony 2025-02-11.

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: Kattegat

Sortuj według:

Ogranicz wyniki do:

Development and dynamics of a coastal sub-surface phytoplankton bloom in the southwest Kattegat, Baltic Sea

100%

Lund-Hansen L. C.

Oceanologia

2006

tom No. 48 (3)

433-446

The study was based on CTD-casts performed on 5 consecutive days at 7 positions along a shallow- to deep-water transect during the spring bloom in the southwest Kattegat. The development, dynamics and fate of the sub-surface chlorophyll maximum (SCM) are described. The SCM developed at a constant rate of 1.4 mg chl a m-3 d-1, which is equal to a carbon fixation rate of 49.0 mg C m-3 d-1. The SCM developed at 6 m depth at low irradiance levels (10-43.0 žE m-2 s-1). Chl a concentrations reached up to 23 mg chl a m-3 in the centre of the SCM. Growth rates in the SCM were estimated at 0.82 d-1. The water column was only weakly stratified, with nutrients in excess in the whole of the water column. The SCM was relocated vertically to depths below the photic zone by wind-induced advection between the bay and the outer Kattegat. There were indications of a horizontal relocation of the SCM by an internal standing wave. Application of high spatial and temporal resolution made it possible to estimate key SCM parameters, such as growth rates [mg chl a m-3 d-1] and carbon fixation rate [mg C m-3 d-1], on the basis of chl a variations in time and space.

The impact of the modified ships’ routes in the Kattegat on the safety of navigation at the entrance to the Baltic Sea

75%

Kerbrat A. , Guze S.

tom nr 75 (147)

79--88

Since the 1970s, ships in the Kattegat area and the Baltic Sea entrances have been advised to use one of the routes established by the Danish Maritime Safety Administration. As time passed, traffic increased significantly, demanding adjustments to the introduced solutions to accommodate new volumes of ships passing through the entrances to the Baltic Sea. It is estimated that about 70,000 vessels are passaged via Kattegat yearly. Additionally, an increase in the traffic of fishing vessels and small pleasure crafts of different types has been observed, necessitating regulation to ensure the safety of navigation for everyone involved. Therefore, on the 1st of July 2020, a new routing system was introduced in the area of Kattegat by the decision of the International Maritime Organization (IMO). This paper focuses on the exact changes made and how those changes may influence the safety of navigation in Kattegat and the Sound, considering the COLREG rules and human factors in planning and executing passage via this area. A short presentation of recent accidents, and a study of difficulties arising from the new traffic organization, will be given. Brief traffic analysis is conducted using IWRAP MK II software, and historical AIS data from research will advance a more detailed examination and simulations. Finally, the introduced routing system’s effectiveness is compared using density plots from chosen periods. Furthermore, the analysis of the influence on the safety of navigation, as the introduced solution, is observed to be unusual. New routings have been in force for over two years and are accepted and used by most merchant vessels operating in Kattegat. Even so, this period is too short to clearly state that it is completely safe.

Transparency of the North Sea and Baltic Sea - a Secchi depth data mining study

75%

Aarup T.

nr 3

This paper presents the results of a Secchi depth data mining study for the North Sea – Baltic Sea region. 40,829 measurements of Secchi depth were compiled from the area as a result of this study. 4.3% of the observations were found in the international data centers [ICES Oceanographic Data Center in Denmark and the World Ocean Data Center A (WDC–A) in the USA], while 95.7% of the data was provided by individuals and ocean research institutions from the surrounding North Sea and Baltic Sea countries. Inquiries made at the World Ocean Data Center B (WDC–B) in Russia suggested that there could be significant additional holdings in that archive but, unfortunately, no data could be made available. The earliest Secchi depth measurement retrieved in this study dates back to 1902 for the Baltic Sea, while the bulk of the measurements were gathered after 1970. The spatial distribution of Secchi depth measurements in the North Sea is very uneven with surprisingly large sampling gaps in the Western North Sea. Quarterly and annual Secchi depth maps with a 0.5◦×0.5◦ spatial resolution are provided for the transition area between the North Sea and the Baltic Sea (4◦E–16◦E, 53◦N–60◦N).