150 



alone. It is noteworthy as well that with deeper water associated with sea 

 level rise, waves would be admitted more freely, thereby decreasing fluid 

 stratification by virtue of greater mixing in the vertical direction, 

 particularly in estuary mouths . 



Another important research area is related to the development and 

 motion of fronts due to salinity, temperature and sediment density 

 gradients. Understanding the behavior of these fronts is vitally important 

 to a range of water quality and ecological issues. 



It must be mentioned that most of the work done to date appears to 

 have dealt with such effects as those related to channel deepening or 

 changes in upstream river hydrology, rather than sea level rise. As noted, 

 sea level rise can also increase the coastal tide and wave action, 

 particularly if the coastline is rocky, and does not recede, while water 

 depth increases. A similar situation can also arise if the shoreline is 

 erodible, but sea level rise is so rapid as to prevent depths at the mouth 

 from achieving quasi-equilibrium with the hydrodynamic forcing. This would 

 lead to a situation wherein the estuarine mouth would be in deeper water, 

 and where the tide (and waves) would arrive with lesser hindrance due to 

 reduced bottom friction and lesser chance of wave breaking in the offshore 

 waters. In most work carried out so far, the coastal tide (and waves) is 

 typically assumed to practically remain unchanged. 



