Summary
347
bordered by Colombia, Panama, and Costa Rica; and the Gulf of Honduras
(see Chap. 1 by Heyman and Kjerfve).
4 Tides, Waves, and Relative Sea Level
Tidal processes break down vertical stratification in the water column,
disperse sediment, nutrients, and pollutants and generate residual tidal circulation in estuaries and bays. Thus, it is important to understand local
manifestation of tidal processes in managing coastal systems. Tidal conditions vary along the coasts of the South American continent. Tides along the
Pacific coast are mostly mixed semidiurnal. Spring tides range from 1.5 min
the south of the continent, 5 min the Gulf of Panama, to more than 7 mat the
mouth of the Colorado River in the inner Gulf of California (see Chap. 22 by
Alvarez-Borrego). Part of the Pacific coast of Mexico until the entrance to
the Gulf of California experiences mixed, mainly diurnal tides with a tidal
range of less than 1 m (see Chap. 20 by Flores Verdugo et al.). South of the
equator, the predominant semidiurnal (M 2 ) tidal phase progresses from
north to south along the Pacific coast of South America, consistent with the
propagation of a Kelvin wave. The progression of the tidal phase from the
Gulf of Panama to the Gulf of California cannot easily be attributed to a
large-scale amphidromic system, whereas along the Pacific coast of Baja
California the semidiurnal phase progresses northward, also consistent
with the propagation of a Kelvin wave (Fig. 3).Along the Atlantic coast south
of the mouth of the Amazon River, tides are mostly semi diurnal with a northward progression of the dominant M 2 phase. Macrotidal conditions occur
on the broad Patagonian shelf, including the entrance to the Strait of Magellan, with peak spring tides exceeding 11 m at Rio Gallegos, Argentina. The
coast between the mouth of the Rio de la Plata estuary and Cabo Frio, Brazil,
experiences mostly mixed semidiurnal or diurnal tides (range <1m).
Macrotides with spring ranges exceeding 6 m also occur in inshore waters
along the coast of northern Brazil (Maranhao and Pani) and the mouth of
the Amazon River. North of the equator the spring tidal range decreases
from 6 to 2m in the delta of the Orinoco (see Chap. 4 by Conde) and the
semidiurnal tide occurs largely in phase. Within the Caribbean, the tide is
microtidal with an average range of 0.2 m. The tide is mixed and mainly
diurnal in the eastern portion of the Caribbean basin, then becomes diurnal
and further to the west mixed and mainly diurnal, and in the western portion of the basin mixed and mainly semidiurnal (Kjerfve 1981; Fig. 3).
Waves, and the longshore currents they produce, are the main cause of
coastal erosion, alongshore transport, and sediment deposition. Storm
347
bordered by Colombia, Panama, and Costa Rica; and the Gulf of Honduras
(see Chap. 1 by Heyman and Kjerfve).
4 Tides, Waves, and Relative Sea Level
Tidal processes break down vertical stratification in the water column,
disperse sediment, nutrients, and pollutants and generate residual tidal circulation in estuaries and bays. Thus, it is important to understand local
manifestation of tidal processes in managing coastal systems. Tidal conditions vary along the coasts of the South American continent. Tides along the
Pacific coast are mostly mixed semidiurnal. Spring tides range from 1.5 min
the south of the continent, 5 min the Gulf of Panama, to more than 7 mat the
mouth of the Colorado River in the inner Gulf of California (see Chap. 22 by
Alvarez-Borrego). Part of the Pacific coast of Mexico until the entrance to
the Gulf of California experiences mixed, mainly diurnal tides with a tidal
range of less than 1 m (see Chap. 20 by Flores Verdugo et al.). South of the
equator, the predominant semidiurnal (M 2 ) tidal phase progresses from
north to south along the Pacific coast of South America, consistent with the
propagation of a Kelvin wave. The progression of the tidal phase from the
Gulf of Panama to the Gulf of California cannot easily be attributed to a
large-scale amphidromic system, whereas along the Pacific coast of Baja
California the semidiurnal phase progresses northward, also consistent
with the propagation of a Kelvin wave (Fig. 3).Along the Atlantic coast south
of the mouth of the Amazon River, tides are mostly semi diurnal with a northward progression of the dominant M 2 phase. Macrotidal conditions occur
on the broad Patagonian shelf, including the entrance to the Strait of Magellan, with peak spring tides exceeding 11 m at Rio Gallegos, Argentina. The
coast between the mouth of the Rio de la Plata estuary and Cabo Frio, Brazil,
experiences mostly mixed semidiurnal or diurnal tides (range <1m).
Macrotides with spring ranges exceeding 6 m also occur in inshore waters
along the coast of northern Brazil (Maranhao and Pani) and the mouth of
the Amazon River. North of the equator the spring tidal range decreases
from 6 to 2m in the delta of the Orinoco (see Chap. 4 by Conde) and the
semidiurnal tide occurs largely in phase. Within the Caribbean, the tide is
microtidal with an average range of 0.2 m. The tide is mixed and mainly
diurnal in the eastern portion of the Caribbean basin, then becomes diurnal
and further to the west mixed and mainly diurnal, and in the western portion of the basin mixed and mainly semidiurnal (Kjerfve 1981; Fig. 3).
Waves, and the longshore currents they produce, are the main cause of
coastal erosion, alongshore transport, and sediment deposition. Storm