Characteristics and inter-annual changes in temperature, salinity and density distribution in the Gulf of Riga

• Autorzy: Skudra M. , Lips U.

Identyfikatory

DOI

10.1016/j.oceano.2016.07.001

• Języki publikacji: EN

Abstrakty

EN

Available CTD profiles from the Gulf of Riga (May–August, 1993–2012) were analyzed to study inter-annual and long-term changes in temperature, salinity and density in relation to river runoff and atmospheric forcing (e.g. Baltic Sea Index). To describe temporal changes in vertical stratification, the upper mixed layer (UML) and deep layer (DL) parameters were estimated. On average the UML depth increases from 8.7 m in May to 9.0, 11.5 and 13.7 m in June, July and August, respectively, and the UML temperature increases from 8.0°C to 12.5, 18.7 and 18.6°C (May, June, July and August) while the UML salinity increases from 4.90 g kg⁻¹ to 5.14, 5.28 and 5.38 g kg⁻¹, respectively. High correlation (r = −0.82) was found between the inter-annual changes in river runoff (spring) and mean salinity in the UML in August as well as between DL mean salinity (r = 0.88) and density (r = 0.84) in the Irbe Strait and DL mean salinity and density in the Gulf of Riga. Inter-annual changes in the UML depth as well as in DL salinity and density had a significant correlation with the changes in Baltic Sea Index. The strongest stratification (August) can be observed in the years with the highest UML temperature and the highest river run-off in spring. We suggest that the predicted increase in water temperature and changes in river run-off due to the climate change would result in faster development of the seasonal thermocline in spring and stronger vertical stratification in summer.

Słowa kluczowe

EN

Gulf of Riga; temperature; salinity; vertical stratification; internal rossby radius

• Wydawca: Polish Academy of Sciences, Institute of Oceanology ; Elsevier
• Czasopismo: Oceanologia
• Rocznik: 2017
• Tom: No. 59 (1)
• Strony: 37--48
• Opis fizyczny: Bibliogr. 30 poz., mapy, tab., wykr.

Twórcy

autor

Skudra M.

• Marine Systems Institute, Tallinn University of Technology, Tallinn, Estonia
• Latvian Institute of Aquatic Ecology, Riga, Latvia

autor

Lips U.

• Marine Systems Institute, Tallinn University of Technology, Tallinn, Estonia

Bibliografia

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Uwagi

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).