2
Chemical Oceanography, 4th Edition
1. The Geochemical Oceans Sections Study (GEOSECS) from 1970 to 1980
2. The World Ocean Circulation Experiment (WOCE) from 1990 to 2000
3. The Climate Variability and Predictability (CLIVAR) project from 2001 to the present
Early theoretical studies of surface tides were made by Newton and Laplace and of
waves by Gerstner and Stokes. The Scandinavian meteorologists Bjerknes, Ekman, and
Helland- Hansen developed the field of dynamic oceanography. Recent studies have examined coastal processes, western boundary currents (such as the Gulf Stream), and smallscale fluctuations, eddies or rings, bottom water movement, and the use of tracers to study
large- scale mixing processes. Currently, physical and chemical oceanographers are participating in CLIVAR. This study is a continuation of the WOCE program. This global
study includes a reoccupation of some of the long lines that were studied as part of the
Joint Global Ocean Flux Study (JGOFS) and Ocean–Atmosphere Carbon Exchange Study
(OACES) CO 2 programs, which are discussed further elsewhere in this book. Future oceanography will have a strong component dealing with satellites and remote sensing techniques utilizing moored arrays of instruments in the oceans. This global ocean observing
system (GOOS) will be concerned with making continuous physical and chemical measurements of the global ocean. It should also be pointed out that a new International Study
of Marine Biogeochemical Cycles of Trace Elements and Their Isotopes has been initiated.
It is called GEOTRACES. These studies should provide a wealth of information on the
effect that trace metals have on biogeochemical processes in the oceans.
1.2 Physical Characteristics of the Oceans
Some general physical features of the oceans to keep in mind are the following:
1. Of the earth’s surface, 71% is covered by the oceans (361 × 10 6 km 2 ).
2. The deepest trench is 11,022 m (Mariana); the highest mountain on land is 8848 m
(Mt. Everest).
3. The Southern Hemisphere has the largest percentage of water (80.9%) in the oceans.
4. The world oceans are made up of 50% Pacific, 29% Atlantic, and 21% Indian Oceans
by volume.
5. The major depth zone of the ocean (74%) lies between 3 and 6 km.
6. Of ocean waters, 50% have a temperature range between 1.3 and 3.8°C and salinity
(grams of salt in 1 kg of seawater) between 34.6 and 34.8.
7. The mean depth of the oceans is 3.7 km; the mean temperature is 3.5°C, and the
mean salinity is 34.7.
The major features of the ocean floor are shown in Figure 1.1. Continental margins show
a wide range of unique features, and a number of studies have been conducted of seamounts that occur in deep- sea basins. The detailed structure has been examined for the
midocean ridge systems (see Figure 1.2).
The shore is the part of the land mass close to the sea that has been modified by the
sea. The continental shelf is seaward from the shore and has a gradient or slope of 1 to
Chemical Oceanography, 4th Edition
1. The Geochemical Oceans Sections Study (GEOSECS) from 1970 to 1980
2. The World Ocean Circulation Experiment (WOCE) from 1990 to 2000
3. The Climate Variability and Predictability (CLIVAR) project from 2001 to the present
Early theoretical studies of surface tides were made by Newton and Laplace and of
waves by Gerstner and Stokes. The Scandinavian meteorologists Bjerknes, Ekman, and
Helland- Hansen developed the field of dynamic oceanography. Recent studies have examined coastal processes, western boundary currents (such as the Gulf Stream), and smallscale fluctuations, eddies or rings, bottom water movement, and the use of tracers to study
large- scale mixing processes. Currently, physical and chemical oceanographers are participating in CLIVAR. This study is a continuation of the WOCE program. This global
study includes a reoccupation of some of the long lines that were studied as part of the
Joint Global Ocean Flux Study (JGOFS) and Ocean–Atmosphere Carbon Exchange Study
(OACES) CO 2 programs, which are discussed further elsewhere in this book. Future oceanography will have a strong component dealing with satellites and remote sensing techniques utilizing moored arrays of instruments in the oceans. This global ocean observing
system (GOOS) will be concerned with making continuous physical and chemical measurements of the global ocean. It should also be pointed out that a new International Study
of Marine Biogeochemical Cycles of Trace Elements and Their Isotopes has been initiated.
It is called GEOTRACES. These studies should provide a wealth of information on the
effect that trace metals have on biogeochemical processes in the oceans.
1.2 Physical Characteristics of the Oceans
Some general physical features of the oceans to keep in mind are the following:
1. Of the earth’s surface, 71% is covered by the oceans (361 × 10 6 km 2 ).
2. The deepest trench is 11,022 m (Mariana); the highest mountain on land is 8848 m
(Mt. Everest).
3. The Southern Hemisphere has the largest percentage of water (80.9%) in the oceans.
4. The world oceans are made up of 50% Pacific, 29% Atlantic, and 21% Indian Oceans
by volume.
5. The major depth zone of the ocean (74%) lies between 3 and 6 km.
6. Of ocean waters, 50% have a temperature range between 1.3 and 3.8°C and salinity
(grams of salt in 1 kg of seawater) between 34.6 and 34.8.
7. The mean depth of the oceans is 3.7 km; the mean temperature is 3.5°C, and the
mean salinity is 34.7.
The major features of the ocean floor are shown in Figure 1.1. Continental margins show
a wide range of unique features, and a number of studies have been conducted of seamounts that occur in deep- sea basins. The detailed structure has been examined for the
midocean ridge systems (see Figure 1.2).
The shore is the part of the land mass close to the sea that has been modified by the
sea. The continental shelf is seaward from the shore and has a gradient or slope of 1 to