NOAA Long Line Cruises : N95F
Results

1. Chlorophyll depth profiles show that between 43^°S and 30^°S, the vertical variability is low. There are high values (0.3 to 0.4 ug l^-1 ) for chlorophyll found from the surface down to 100 meters. Between 30^°S and 15^°N, the higher chlorophyll values, ranging from 0.2-0.3 ug l^-1 , are found from 100 meters to 175 meters. North of approimately 15^°S, the values of chlorophyll concentration increase. This area of higher concentrations, starts at approximately 100 meters in depth at 15^°S and steadily moves towards the surface as the transect moves north and nears the coast.
2. Phaeopigment profiles show an area of higher concentraions between 65 meters and 110 meters from 9^°S to the equator. Here, the concentration of phaeopigments is approximately 0.4 ug l^-1 .
3. The primary productivity depth profile indicates that primary productivity is high between 40^°S and 30^°S. However, these high values, ranging from 5 to 15 mgC m^-3 d^-1, are only seen in the upper 50 meters. Then, at approximately 30^°S, the productivity delcines and remains low throughout the profile until 15^°S. Between these latitudes, there is a gyre present. At 16°S the high values are present again and are found as deep as 90 meters at 6°S. As the transect nears the coast, the values for primary productivity increase to as high as 20 mgC m^-3 d^-1 and are found at increasingly shallower depths.

4. Surface chlorophyll ranges in value from 0.2 - 0.4 ug l^-1 between 43^° S and 32°S. Then, at 30°S the values decrease greatly to 0.05 ug l^-1 and remain low until approximately 11°S where there is a small peak at 0.20 ug l^-1. There is another peak at 2°N where the value is near 0.3 ug l^-1.
5. Surface carbon follows a similar pattern with value rising from 1 ug l^-1 around 43°S and rising to 13 ug l^-1 at 32°S. The concentration then decreases and remains low until a small peak to 6ug l^-1at 12°S which is followed by a larger peak, 20 ug l^-1, at 2°N.
6. Primary productivity index for the surface shows a steady increase in primary productivity from 0 ug l^-1 at 43°S to just under 80 ug l^-1 at 22°S. The primary productivity then appears to decline sharply and resume increasing at a slower rate from 30 ug l^-1 at 20°S to approximately 70 ug l^-1 at 2°N.

7. Integrated chlorophyll values show a decline from 20 mg m^-2 at 40^o S to 4 mg m^-2 at 24^o S. Moving north from this point there is a more gradual increase to 21 mg m^-2 at 2^o S. Continuing towards the equator, there is a slight dip in the values to around 15 mg m^-2.

8. Integrated carbon values show a similar pattern. They are relatively high between 40^o S and 30^o S, around 250 mg m^-2 d^-1, and then decline to approximately 100 mg m^-2 d^-1 at 24^o S. Moving north from this point, the values rise more or less steadily to about 675 mg m^-2 d^-1 at 1^° N.

9. The integrated primary productivity index (PB) indicates that the productivity rises from about 14 mg C mg chl d^-1 at 43^°S to ~30 mg C mg chl d^-1 at 33^°S. Following this rise, there is a slight dip and then the values rise again to near 37 mg C mg chl d^-1at approximately 23^°S. After another slight dip the values return to near 37 mg C mg chl d^-1 around 10^°S. From here, the productivity appears to decrease steadily to 22 mg C mg chl d^-1 at the equator. Continuing northward towards the coastal waters, the productivity rises sharply to near 51 mg C mg chl d^-1at 2^°N.

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