Sea-Surface Temperature Estimations Using a Modem Analog Technique
Results
Temperature Reconstructions
Although temperature calculations were performed
both with and without the distance-weighting option, we will limit our discussion of results to the
distance-weighted values obtained. It shall suffice
to note that the distance-weighted values in the
tropical cores, GeoB 1523 and GeoB 2204, averaged 0.65°C warmer overall than the non-distanceweighted temperatures, and in the Rio Grande Rise
cores, GeoB 1312 and GeoB 1309, the distanceweighted temperatures averaged 0.65°C cooler
overall than the non-distance-weighted temperatures.
The results for warm- and cold-season SST's
are illustrated for the tropical cores in Fig. 3 (a),
and for the Rio Grande Rise cores in Fig. 3 (b). Also
included on these figures are oxygen isotope curves
on the right side of each plot, which provide a general stratigraphic orientation, with the glacial stages
indicated by the gray areas. The two tropical cores
are characterized by warm, fairly stable temperatures, especially the warm-season curves (for the
most part between 27° and 28° C), except for a
significant excursion to cooler temperatures in the
upper part of isotope stage 6. In the Brazil Slope
core (GeoB 2204), the warm-season temperature
drops to about 2° below the average for the rest of
the core; and in the Ceara Rise core (GeoB 1523),
the value sinks to about 3° below the average. This
anomaly has also been reported by McIntyre et al.
(1989) in transfer-function temperatures calculated
for two additional west-equatorial Atlantic cores,
which also have otherwise fairly low-amplitude
Fig. 3. SIMMAX MAT warm- and cool-season temperature estimates in °C (distance-weighted) for (a) the tropical cores and (b) the Rio Grande Rise cores, plotted
against em depth in the cores. Stratigraphic framework
for the area is provided by S'80 curves (PDB) at the top
of each plot (for GeoB 1523, S'80 values from R. Schneider, for GeoB 2204, S'80 values from A. Dtirkoop).
a.
SIM.IlAX SST (d.g.C)
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75
Results
Temperature Reconstructions
Although temperature calculations were performed
both with and without the distance-weighting option, we will limit our discussion of results to the
distance-weighted values obtained. It shall suffice
to note that the distance-weighted values in the
tropical cores, GeoB 1523 and GeoB 2204, averaged 0.65°C warmer overall than the non-distanceweighted temperatures, and in the Rio Grande Rise
cores, GeoB 1312 and GeoB 1309, the distanceweighted temperatures averaged 0.65°C cooler
overall than the non-distance-weighted temperatures.
The results for warm- and cold-season SST's
are illustrated for the tropical cores in Fig. 3 (a),
and for the Rio Grande Rise cores in Fig. 3 (b). Also
included on these figures are oxygen isotope curves
on the right side of each plot, which provide a general stratigraphic orientation, with the glacial stages
indicated by the gray areas. The two tropical cores
are characterized by warm, fairly stable temperatures, especially the warm-season curves (for the
most part between 27° and 28° C), except for a
significant excursion to cooler temperatures in the
upper part of isotope stage 6. In the Brazil Slope
core (GeoB 2204), the warm-season temperature
drops to about 2° below the average for the rest of
the core; and in the Ceara Rise core (GeoB 1523),
the value sinks to about 3° below the average. This
anomaly has also been reported by McIntyre et al.
(1989) in transfer-function temperatures calculated
for two additional west-equatorial Atlantic cores,
which also have otherwise fairly low-amplitude
Fig. 3. SIMMAX MAT warm- and cool-season temperature estimates in °C (distance-weighted) for (a) the tropical cores and (b) the Rio Grande Rise cores, plotted
against em depth in the cores. Stratigraphic framework
for the area is provided by S'80 curves (PDB) at the top
of each plot (for GeoB 1523, S'80 values from R. Schneider, for GeoB 2204, S'80 values from A. Dtirkoop).
a.
SIM.IlAX SST (d.g.C)
;.~tI~~::t
"
. .
"
,,,
,.,
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." ..,
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,.. ..... ... p 0
o u.. 0 till 0
~ laO /G . .. "."
SI MMAX SST (d.g C)
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.,
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75