High latitude ocean gateway changes are thought to play a key role in Cenozoic climate evolution. However, the underlying ocean dynamics are poorly understood. Here we use a fully coupled atmosphere-ocean model to investigate the effect of ocean gateway formation that is associated with the subsidence of the Greenland-Scotland Ridge. We find a threshold in sill depth (∼50 m) that is linked to t...

The light absorbing fraction of dissolved organic carbon (DOC), known as chromophoric dissolved organic matter (CDOM) showed wide seasonal variations in the temperate estuarine zone in front of the Po River mouth. DOC concentrations increased from winter through spring mainly as a seasonal response to increasing phytoplankton production and thermohaline stratification. The monthly dependence of...

The sensitivity of oxygen depletion in turbid estuaries to parameters like freshwater discharge, depth, and sediment availability is investigated using an idealized model. The model describes tidally averaged circulation and suspended sediment concentration (SSC), which are input into an advection–diffusion sink module of dissolved oxygen (DO). Based on the analysis of field data collected in t...

An equilibrium model based on the CO2 system was developed to model pH throughout the estuarine salinity range using the composition of the river and seawater end members. In order to validate the model, a spectrophotometric method was used to measure pH in an estuary and laboratory mixing experiments. The model successfully represented the measured pH values ( 0.1 pH units) for three different...

We conducted irradiation experiments with riverine, estuarine, and marine water samples to investigate the possibility of photochemical methane (CH4) formation. CH4 photoproduction was undetectable under oxic conditions or in the absence of methyl radical precursors indicating that its photochemical formation is negligible in the present ocean. Significant photochemical CH4 production was obser...

Benthic bivalves are important links between primary production and consumers, and are essential intermediates in the flow of energy through estuarine systems. However, information on the diet of filter feeding bivalves in estuarine ecosystems is uncertain, as estuarine waters contain particulate matter from a range of sources and as bivalves are opportunistic feeders. We surveyed bivalves at d...

Recent advances in our understanding of estuarine circulation and salinity structure are reviewed. We focus on well- and partially mixed systems that are long relative to the tidal excursion. Dynamics of the coupled system of width- and tidally averaged momentum and salt equations are now better understood owing to the development of simple numerical solution techniques. These have led to a gre...

The composition of the mesozooplanktonic community was studied in the Punta Morales estuary, Gulf of Nicoya, Pacific coast of Costa Rica, during 1997. Oblique plankton hauls were performed during high and low tide using a 280 microm mesh screen net equipped with a flowmeter. The community was characterized by holoplanktonic and meroplanktonic organisms. For the holoplanktonic community, the mai...

Through the analysis of benthic foraminifera in soft bottom sediments Laizhou Bay – Yellow River Delta system, this study characterized foraminiferal biotopes and explored possibility obtaining an index ecological quality comparable with other estuarine coastal environments world. Five have been identified their distribution patterns highlight stress from marine-fluvial water mixing pollution. ...