Predictions in the North Sea
255
above can be used to indicate salient features of the annual cyc1e of nutrients. The
approach involves combining model simulations of the seasonal cyc1e with related
observations and thereby inferring grazing and re-cyc1ing rates. Such simulations
emphasise the importance of the oceanic inputs and the limited effect, away from
the coastal fringe, of riverine and coastal inputs.
The development of nutrient modelling promises to be accelerated by the rapid
development of autonomous sensors combined with the aircraft surveillance noted
earlier.
13.4 Ways forward - future developments
This paper has generalIy described discrete simulations (i.e. one parameter in
isolation) or with 'information flow' (i.e. interaction) in one direction only, e.g.
transport paths defining tracer mixing. Ultimately fulIy coupled models run operationalIy will be required. As an example of this interactive requirement, consider
fine sediments which are important as the medium by which many adsorbed polIutants are carried from river to estuary, estuary to coastal zone and thence to shelf
seaJocean. Suspended sediments also influence the biology of the coastal zone by
their extinction oflight (limiting photosynthesis in deeper turbid waters).
One exciting 'Grand Challenge' is to understand and thence predict coastal bathymetric evolution. New approaches are necessary to bridge the gulf between geomorphologists and process modellers. The 'Soft' Defence approach to coastal
protection (i.e. avoidance offixed installations), now widely adopted, accentuates
this Challenge. Exc1uding engineering influences, our present-day coastlines generalIy reflect the balance between geology, fluvial discharge, supply of mobile sediments, exposure to tides, storm surges and waves and the rate of change of mean
sea level. The transport of mobile coastal sediment is the result of complex interactions between each of these dynamical processes within the governing framework
of the instantaneous bathymetry - which is itself evolving via their integrated
impacts. Over longer time scales some (evolving) balance will be achieved
between the evolving bathymetry due to erosion and settlement of sediment and the
subsequent modification of the forcing mechanisms. To reproduce this evolution
requires fine resolution models run in operational or pre-operational mode. Tidal
analyses of suspended sediment time-series (Fig. 13.8 ), is a related challenge.
Relict features such as submerged sand banks can provide indications oflong-term
bathymetry evolution providing their governing characteristics can be accurately
determined (Huthnance 1982). Long term predictions in Shelf Seas must consider
the contribution to and effect from global polIution, specificalIy possible greenhouse effects such as rise in mean sea level and meteorological changes. The widespread impact of such phenomena emphasises the necessity for international cooperation in alI aspects of these studies. Long-term data sets are vital for such programmes, systematic marine monitoring programmes must be initiated, involving
combinations ofremote sensing, sea-truth moorings and coastal stations.
255
above can be used to indicate salient features of the annual cyc1e of nutrients. The
approach involves combining model simulations of the seasonal cyc1e with related
observations and thereby inferring grazing and re-cyc1ing rates. Such simulations
emphasise the importance of the oceanic inputs and the limited effect, away from
the coastal fringe, of riverine and coastal inputs.
The development of nutrient modelling promises to be accelerated by the rapid
development of autonomous sensors combined with the aircraft surveillance noted
earlier.
13.4 Ways forward - future developments
This paper has generalIy described discrete simulations (i.e. one parameter in
isolation) or with 'information flow' (i.e. interaction) in one direction only, e.g.
transport paths defining tracer mixing. Ultimately fulIy coupled models run operationalIy will be required. As an example of this interactive requirement, consider
fine sediments which are important as the medium by which many adsorbed polIutants are carried from river to estuary, estuary to coastal zone and thence to shelf
seaJocean. Suspended sediments also influence the biology of the coastal zone by
their extinction oflight (limiting photosynthesis in deeper turbid waters).
One exciting 'Grand Challenge' is to understand and thence predict coastal bathymetric evolution. New approaches are necessary to bridge the gulf between geomorphologists and process modellers. The 'Soft' Defence approach to coastal
protection (i.e. avoidance offixed installations), now widely adopted, accentuates
this Challenge. Exc1uding engineering influences, our present-day coastlines generalIy reflect the balance between geology, fluvial discharge, supply of mobile sediments, exposure to tides, storm surges and waves and the rate of change of mean
sea level. The transport of mobile coastal sediment is the result of complex interactions between each of these dynamical processes within the governing framework
of the instantaneous bathymetry - which is itself evolving via their integrated
impacts. Over longer time scales some (evolving) balance will be achieved
between the evolving bathymetry due to erosion and settlement of sediment and the
subsequent modification of the forcing mechanisms. To reproduce this evolution
requires fine resolution models run in operational or pre-operational mode. Tidal
analyses of suspended sediment time-series (Fig. 13.8 ), is a related challenge.
Relict features such as submerged sand banks can provide indications oflong-term
bathymetry evolution providing their governing characteristics can be accurately
determined (Huthnance 1982). Long term predictions in Shelf Seas must consider
the contribution to and effect from global polIution, specificalIy possible greenhouse effects such as rise in mean sea level and meteorological changes. The widespread impact of such phenomena emphasises the necessity for international cooperation in alI aspects of these studies. Long-term data sets are vital for such programmes, systematic marine monitoring programmes must be initiated, involving
combinations ofremote sensing, sea-truth moorings and coastal stations.