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Coastal Ocean Dynamics Seventh course: Estuarine Dynamics. Hans Burchard Leibniz Institute for Baltic Sea Research Warnemünde hans.burchard@io-warnemuende.de. The principle of estuarine circulation. MacCready and Geyer (2010). Knudsen formula of 1900. Volume conservation :. s=0.
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Coastal Ocean Dynamics Seventh course: Estuarine Dynamics Hans Burchard Leibniz Institute for Baltic Sea Research Warnemünde hans.burchard@io-warnemuende.de
The principleofestuarinecirculation MacCreadyand Geyer (2010)
Knudsen formulaof 1900 Volume conservation: s=0 Salt conservation: 0
Analytical solutionforestuarinecirculation Balance betweenpressuregradientandfriction: . With weobtaintheanalyticalsolution: .
Tidalstraining after flood after ebb MacCreadyand Geyer (2010) after Simpson et al. (1990)
Estuarinecirculation due totidalstraining 75% level 75% level MacCready & Geyer (2010) after Jay & Musiak (1994)
Simple modelsimulationsofestuarinecirculation undertidallyenergeticconditions Estuarinecirc. Withfull-scale1D model (GOTM, www.gotm.net): Gravitationalcirculation andtidalstrainingprofiles canbedecomposed. Straining Gravitational Result: Tidal straining makes about 2/3 of estuarine circulation. Burchard andHetland (JPO 2010)
Lateral circulation in tidalestuaries Floodcurrentsarefaster in thedeepchannel such thatsalinitybecomeshigher in thechannelcentrethanatthesides. This lateral densitygradientthencauses lateral circulation. Ebbisviceversa. MacCready & Geyer (2010)
Floating material collectedattidal front duringflood (Conwy River, Wales, UK) Nunes & Simpson (1985)
Estuarinecirculation due to lateral circulation Duringflood high (positive) surfacemomentumisverticallytransportedtothenearbedregion. Duringebb, relatively high (negative, but less negative than in channelcentre) istransportedfromthesidestothecentralnear-bedregion. This bothsupportsestuarinecirculation. MacCready & Geyer (2010)
Enhancement of estuarine circulation in channelised tidal flow (2D slice modelling with GETM) www.getm.eu Burchard et al. (JPO 2011)
Transverse structure ofestuarinecirculation Gravitationalcirculation Tidalstrainingcirculation Advectivecirculation Barotropiccirculation Burchard et al. (JPO 2011)
Estuarine circulation drives SPM fluxes
EstuarinecirculationdrivesSPM fluxes Observations in the Elbe estuary: Kappenberg et al. (1995)
Generation ofestuarineturbiditymaxima(ETMs) Sediment accumulation
Consequencesof estuarinecirculation on sedimenttransport ETM ETM = estuarineturbiditymaximum Jay andMusiak (1994)
Modelling (2DV) ETM formation Burchard and Baumert (1998)
Observationsof ETM in lower Elbe River Run-off Neu-Darchau = 707 m3/s Salinity (g/kg) Courtesy Jens Kappenberg
Modelling (3D) ETM formation lowwater ebbtide high water floodtide Burchard et al. (2004)
Ems ashyperturbidestuary Talke et al. (2009)
Isthere a positive feedbackloop in estuarie? Winterwerp, 2013
Whathappenedtothe Ems estuary? Pers. Comm. Henk Schuttelaars, 2013 Elbe Winterwerp, 2013