Meeting:Abstract 2011 CSDMS meeting-053: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
<!--{{CSDMS meeting program template | |||
|CSDMS meeting first hydrological choice=I am not interested | |||
|CSDMS meeting second hydrological choice=I am not interested | |||
|CSDMS meeting first terrestrial choice=I am not interested | |||
|CSDMS meeting second terrestrial choice=I am not interested | |||
|CSDMS meeting first coastal choice=SWAN | |||
|CSDMS meeting second coastal choice=ADCIRC | |||
|CSDMS meeting first marine choice=ROMS | |||
|CSDMS meeting second marine choice=WaveWatch III^TM | |||
|CSDMS meeting first carbonate choice=I am not interested | |||
|CSDMS meeting second carbonate choice=I am not interested | |||
|CSDMS meeting first tool choice=I am not interested | |||
|CSDMS meeting second tool choice=I am not interested | |||
}}--> | |||
{{CSDMS meeting personal information template | {{CSDMS meeting personal information template | ||
|CSDMS meeting first name=Malcolm | |CSDMS meeting first name=Malcolm | ||
| Line 16: | Line 30: | ||
}} | }} | ||
{{CSDMS meeting abstract template | {{CSDMS meeting abstract template | ||
|CSDMS meeting abstract= | |CSDMS meeting abstract= The seasonal depletion of oxygen (hypoxia) is a significant water quality issue in Chesapeake Bay. Billions of dollars have been spent on nutrient reduction with the goal of decreasing the extent and severity of summer hypoxia. However, assessing the effectiveness of these efforts is often confounded by the complexity and variability of the physical processes that control the distribution of dissolved oxygen in the Bay. The goal of this presentation is to assess the importance of the variations in physical forcing on modulating dissolved oxygen in Chesapeake Bay using a 3-D circulation model with an extremely simple formulation for oxygen dynamics. The model uses a depth-dependent oxygen utilization (respiration) that is constant in time and exchanges oxygen with the atmosphere via a surface flux. Despite the simplicity of the approach, this model can accurately simulate the observed seasonal cycle of hypoxia in the Bay. Further, because the biological utilization of oxygen is constant in time, the model effectively isolates the role of physical processes in modulating dissolved oxygen in this system. Model runs demonstrate that variations in wind speed and direction are the most important physical variables in controlling seasonal hypoxia. Secondary effects are attributed to variations in water temperature. Surprisingly, the model suggests that the magnitude of river discharge has little impact on the extent and severity of seasonal hypoxia in the Bay. A 15-year simulation with this model demonstrates some skill, but fails to capture much of the observed inter-annual variability in hypoxic volume. Model residuals are statistically correlated with integrated nitrogen loading, emphasizing the importance of biological processes in controlling the inter-annual variability. | ||
}} | }} | ||
{{blank line template}} | {{blank line template}} | ||
{{CSDMS meeting program template1 | |||
|CSDMS meeting first | |CSDMS meeting first day choice=CEM | ||
|CSDMS meeting second day choice=Delft3D | |||
|CSDMS meeting third day choice=I can not attend a clinic | |||
}} | |||
|CSDMS meeting second | |||
|CSDMS meeting | |||
}} | |||
{{CSDMS meeting logistics template | {{CSDMS meeting logistics template | ||
|Attend all days=Yes | |Attend all days=Yes | ||
Revision as of 15:47, 4 October 2011
"USA" is not in the list (Afghanistan, Albania, Algeria, Andorra, Angola, Antigua and Barbuda, Argentina, Armenia, Australia, Austria, ...) of allowed values for the "Country member" property.
Browse abstracts
Malcolm Scully choose to not submit an abstract for this conference.
[[Image:|300px|right|link=File:]]The seasonal depletion of oxygen (hypoxia) is a significant water quality issue in Chesapeake Bay. Billions of dollars have been spent on nutrient reduction with the goal of decreasing the extent and severity of summer hypoxia. However, assessing the effectiveness of these efforts is often confounded by the complexity and variability of the physical processes that control the distribution of dissolved oxygen in the Bay. The goal of this presentation is to assess the importance of the variations in physical forcing on modulating dissolved oxygen in Chesapeake Bay using a 3-D circulation model with an extremely simple formulation for oxygen dynamics. The model uses a depth-dependent oxygen utilization (respiration) that is constant in time and exchanges oxygen with the atmosphere via a surface flux. Despite the simplicity of the approach, this model can accurately simulate the observed seasonal cycle of hypoxia in the Bay. Further, because the biological utilization of oxygen is constant in time, the model effectively isolates the role of physical processes in modulating dissolved oxygen in this system. Model runs demonstrate that variations in wind speed and direction are the most important physical variables in controlling seasonal hypoxia. Secondary effects are attributed to variations in water temperature. Surprisingly, the model suggests that the magnitude of river discharge has little impact on the extent and severity of seasonal hypoxia in the Bay. A 15-year simulation with this model demonstrates some skill, but fails to capture much of the observed inter-annual variability in hypoxic volume. Model residuals are statistically correlated with integrated nitrogen loading, emphasizing the importance of biological processes in controlling the inter-annual variability.
