New Computer Fund

Thursday, October 11, 2012

Just Charts Waiting for a Story

Since I have had a few computers crash in the past two years likely due to humid Florida weather, I tend to post stuff on line for safe keeping.  Instead of trying to keep the stuff private, I just let it out there for all to see..  There are lots of Southern Hemisphere Ocean Cores to play with, so I will just post a few charts I think are keepers here from time to time.  References will be a little lax with mainly just the core ID posted unless someone complains, until I either use the charts in a semi-post or just move on.  Geomagnetic fans though might find this one interesting.

SUGGESTED DATA CITATION: Yamamoto, M., et al.  2007.
California Current 136KYr Alkenone Sea Surface Temperature Estimates. 
IGBP PAGES/World Data Center for Paleoclimatology 
Data Contribution Series # 2007-100.
NOAA/NCDC Paleoclimatology Program, Boulder CO, USA.

The Bintanja and van de Wal should make and excellent reference for past sea level.  This chart compares the Herbert et al. 2010 Tropical Eastern Pacific and South China Sea temperature reconstructions.  Opposite axis are used with the Herbert data shifted so the mean value of all three series for the period 0 to 3000 ka, where available, align.  The temperature scale is just roughly adjusted for fit near 2000ka.

This is the same chart from 1500 to 3000 ka with the rough adjustment period in the highlight box.  This is the period which had two closely space magnetic reversals followed by the longer Compass North orientation. 

The first part of the chart which shows the shift circa 900 to 920 ka which starts the rise in Tropical Eastern Pacific Temperature and sea level wide fluctuation range.

The shift in the highlight box not only change the slope of tropical Pacific SST, it appears to have accentuated the longer 400ka orbital cycle.  

The DSD607 is in the Northern Atlantic which provides a good comparison to the tropical eastern Pacific.  The same Herbert et al. 2010 for ODP846 and Lawrence et al. 2010 

Lawrence, K.T., S. Sosdian, H.E. White, and Y. Rosenthal. 2010. 
North Atlantic climate evolution through the Plio-Pleistocene climate transitions. 
Earth and Planetary Science Letters, Vol. 300, Issues 3-4, 
1 December 2010, pp. 329-342. 

Interesting take in the Abstract:

We propose that the expansion of the West Antarctic ice sheet (WAIS) across the MPT increased the production and export of Antarctic Bottom Water from the Southern Ocean and subsequently controlled its incursion into the North Atlantic, especially during glacial intervals. It follows that the early 100 kyr response of BWT implies an early response of the WAIS relative to the northern hemisphere deglaciation. Thus, in the "100 kyr world," both northern hemisphere and southern hemisphere processes affect climate conditions in the North Atlantic Ocean.

I wonder if they noticed the magnetic reversal coordination which could be due to Antarctic Ice Sheet movement.?

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