CHAPTER 19 ,Palaeoenvironmental Reconstructions
Fig. 19.10. Gas chromatograms
of alkenones in cultures of
Emiliania huxleyi at 25 and
10°C, Redrawn from Prahl and
Wakeham (1987)
1
~
'Vi
c:
!l
oS
37:2
37:3
~J *
37:3
I 37:2
37:4
*
38:2 Et
I ~»2M'
38:3 Et
, A
38:2 Et
38:3 Me
38:3 Et ~
*
Time
38:2 Me
435
25 ·C Culture
39:2
10°C Culture
•
Increased sea surface temperatures are associated with El Nino conditions (Fig. 19.12),
because the intensity of coastal upwelling of colder subsurface water in the eastern
tropical Pacific decreases. The "very strong" EI Nino events of Quinn et al. (1987) had
sea surface temperature anomalies of 7-l2 °C, considerably higher than the sea surface temperature derived from alkenone analyses (e.g. about 2°C for the 1982 El Nino).
This temperature difference may be related to the fact that the alkenone-producing
haptophytes may better record the average temperature of the cooler mixed layer rather
than that at the warmer sea surface,
Fig. 19.10. Gas chromatograms
of alkenones in cultures of
Emiliania huxleyi at 25 and
10°C, Redrawn from Prahl and
Wakeham (1987)
1
~
'Vi
c:
!l
oS
37:2
37:3
~J *
37:3
I 37:2
37:4
*
38:2 Et
I ~»2M'
38:3 Et
, A
38:2 Et
38:3 Me
38:3 Et ~
*
Time
38:2 Me
435
25 ·C Culture
39:2
10°C Culture
•
Increased sea surface temperatures are associated with El Nino conditions (Fig. 19.12),
because the intensity of coastal upwelling of colder subsurface water in the eastern
tropical Pacific decreases. The "very strong" EI Nino events of Quinn et al. (1987) had
sea surface temperature anomalies of 7-l2 °C, considerably higher than the sea surface temperature derived from alkenone analyses (e.g. about 2°C for the 1982 El Nino).
This temperature difference may be related to the fact that the alkenone-producing
haptophytes may better record the average temperature of the cooler mixed layer rather
than that at the warmer sea surface,