Monitoring of Pollution by Means of Remote Sensing
531
establishment of the flood currents because of the estuary's configuration (less inertia,
gravity etc.) (Fig.4).
The waters in the Tinto channel are partially blocked during the ebb tide. The
water from the Odiel and El Burro channels flows to the main channel obstructing the
Tinto waters. Only after a one-two hour delay does the Tinto channel manage to drain
to the Padre Santo channel.
During ebb tide interesting patterns of turbidity plumes generated by the
ebbing estuarine waters are found in the main channel mouth. The tidal phase and
coefficient seem to be the main controlling factors as is demonstrated by the
similarities between the turbidity patterns when both parameters have similar values.
1)
2)
3)
low coefficient: little turbid water reaches the end of the jetty and the
turbidity maximum concentrates along the main channel
medium coefficient: the turbid water volume is higher and there is a sharp
westward deflection of the plume
high coefficient: turbid water is pushed away from the jetty and the westward
deflection becomes a clear spiral.
The Punta Umbría channel turbidity plume spreads over a large area because
the volume of water drained during ebbing water is higher than the volume of water
that enters during flooding water. This means that this channel drains some of the
Odiel water. This is important because, at low and medium coefficients, most of the
estuarine water exchange takes place through this channel.
Zoning the Estuary
This is an attempt to establish the typical spatial distribution of water masses in the
estuary and coastal zone for each stage of the tide. To characterize the different
synoptic situations the first step was to group the available images according to the
hydrodynamic situation which they represent. Having checked the state of the tide at
each image, the images were grouped into three sets, high water (+/- 1hour), low water
(+0-2 hours),and ebbing water (1-3 hours before low water) (Table 1). There are no
images for flooding waters.
531
establishment of the flood currents because of the estuary's configuration (less inertia,
gravity etc.) (Fig.4).
The waters in the Tinto channel are partially blocked during the ebb tide. The
water from the Odiel and El Burro channels flows to the main channel obstructing the
Tinto waters. Only after a one-two hour delay does the Tinto channel manage to drain
to the Padre Santo channel.
During ebb tide interesting patterns of turbidity plumes generated by the
ebbing estuarine waters are found in the main channel mouth. The tidal phase and
coefficient seem to be the main controlling factors as is demonstrated by the
similarities between the turbidity patterns when both parameters have similar values.
1)
2)
3)
low coefficient: little turbid water reaches the end of the jetty and the
turbidity maximum concentrates along the main channel
medium coefficient: the turbid water volume is higher and there is a sharp
westward deflection of the plume
high coefficient: turbid water is pushed away from the jetty and the westward
deflection becomes a clear spiral.
The Punta Umbría channel turbidity plume spreads over a large area because
the volume of water drained during ebbing water is higher than the volume of water
that enters during flooding water. This means that this channel drains some of the
Odiel water. This is important because, at low and medium coefficients, most of the
estuarine water exchange takes place through this channel.
Zoning the Estuary
This is an attempt to establish the typical spatial distribution of water masses in the
estuary and coastal zone for each stage of the tide. To characterize the different
synoptic situations the first step was to group the available images according to the
hydrodynamic situation which they represent. Having checked the state of the tide at
each image, the images were grouped into three sets, high water (+/- 1hour), low water
(+0-2 hours),and ebbing water (1-3 hours before low water) (Table 1). There are no
images for flooding waters.