Aluminum (Al)

Atomic number: 13
Atomic weight: 26.98154
Average concentration in ocean: 1.11 nmol/kg
Residence time: 200 yrs

Distribution in ocean
Dissolved aluminum has the vertical profile of a scavenged element.  Concentrations are high at the surface due to input from dust and the concentrations decrease with depth as dissolved Al is sorbed onto sinking particles and carried into the sediments (data). 

Speciation
Aluminum is present in seawater as the hydrolyzed Al (III) species Al(OH)30 and Al(OH)4-. 

Residence time
The residence time was determined from a diffusion-advection-reaction model (Orians and Bruland, 1986).

Analysis
Aluminum was first determined in seawater by forming a fluorescent complex with the organic compound lumogallion (Hydes, 1983).  It can also be determined by graphite furnace atomic absorption spectrophotometry after preconcentration and by flow injection analysis with fluorescence detection.

References