|
|
|
|
|
|
|
![](images/dian9.gif) |
Pushing the frontiers of marine ecological modeling: where are we now and how can we move forward?
|
|
|
Variability of hypoxia in coastal transition zone off Pearl River Estuary: observational and modelling studies P-B3-03-S Dou Li* , Department of Ocean Science, Hong Kong University of Science and Technology Jianping Gan, Department of Ocean Science, Hong Kong University of Science and Technology Presenter Email: dliar@connect.ust.hk |
The deterioration of hypoxia (dissolved oxygen or DO<2 mg l-1) condition in the Pearl River estuary and adjacent coastal waters has attracted more and more attentions recently. In this study, data from two summer cruises in 2017 and 2018 are used to examine spatial and temporal variability of hypoxia in the Pearl River Estuary (PRE) and adjacent coastal waters around Hong Kong. Observations showed that there existed hypoxia occurred the coastal transition zone (CTZ) off PRE featured with two strong hypoxic centers in western and eastern part of the CTZ. We observed high variability of the hypoxia, as reflected by the location, area, thickness and volume of hypoxic waters from field measurements under variable wind, and river runoff and tidal forcing. A three-dimensional (3-D) coupled physical-biogeochemical model was applied to interpret the observed variability and explore the underlying mechanisms for the formation, sustenance and dissipation of hypoxia. Based on the variable physical and biogeochemical forcing conditions during the surveys, we conduct direct simulation on the observed biophysical responses under different forcing conditions. We conducted a series of analyses to determine the intrinsic coupled physical-biogeochemical response to the extrinsic forcing of winds, tides, river discharge of both buoyancy and nutrient loading, and the associated estuarine-shelf circulation in the CTZ. |
|
|
|
|
|
|
|
|