Talk:Marine isotope stages

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OK... who is watching this page? Anyway, an anon added The difference that has puzzled scientists is the current rise in CO2 levels of MIS1, which according to natural trends based on past interglacials should have been steadily decreasing over the last 5000y. This seems a bit odd. I assume its not referring to the last 150y of obviously anthro increase, but its a slightly confused ref to the Ruddiman hypothesis. In which case I think its rather over stated William M. Connolley 20:57, 6 November 2006 (UTC)

Stages

Each stage represents a glacial, interglacial, stadial or interstadial. Interglacials are odd-numbered; glacials are even numbered, one for each stage, starting from the present and working backward in time. For example, the Holocene is MIS1, or O-stage 1, or just stage 1. The previous interglacial is MIS5, or O-stage 5, or just stage 5.

Exceptionally, MIS2-4 refers to some middle part of the last glacial, because when initially interpreted MIS3 looked like an interglacial.

Stadials and interstadials are identified by a letter following the corresponding glacial or interglacial: 5a, 5b, etc. The dates of the stages were obtained by calibrating the graph on known dates by other methods.

MIS 11 approximately 400ka is the most similar to MIS 1. A difference is that CO₂ levels remained steady or rose during MIS1 (before the industrial era), when by analogy to past interglacials, they should have been steadily decreasing over the last 5000 years. This is the basis of the Early anthropocene hypothesis. DuKu , 26 Jan 2010 Needs cleanup. —Preceding unsigned comment added by DuKu (talk • contribs) 06:45, 26 January 2010 (UTC)

To add some detail (originally heard from Nick Shackleton in a lecture) for the numbering of isotope stage 3/4: Emiliani had expected the palaeoclimate cycles to be primarily governed by orbital obliquity, with a 41 kyr cyclicity. So when the first marine records were obtained, and there was a warming about 40 kyr before present, it was allocated an "interglacial" stage number (3). Only later, when it became apparent that the oxygen isotope stratigraphy was overall dominated by 100,000 year cyclicity in the late Pleistocene, was the numbering system modified to give the 100,000 year interglacials odd numbers. But the stage 3/4 numbering had already "stuck" by then; and anyway it is not really a problem.Orbitalforam (talk) 14:19, 25 May 2010 (UTC)

In the article write that there are 50 cycles of MIS, but only MIS 11 are shown. How about others? Stage 5 (a...e) correspond to around 120ka?--Tranletuhan (talk) 07:59, 16 July 2010 (UTC)

In 2010 the Subcommission on Quaternary Stratigraphy (SQS) (http://quaternary.stratigraphy.org/) dumped earlier MIS versions and started using the Lisiecki & Raymo (2005) LR04 Benthic Stack in their ChronoStratigraphical Correlation Table see notes for 2010: http://quaternary.stratigraphy.org/correlation/chart.html, here's the Lisiecki & Raymo (2005) LR04 Stack links page: http://www.lorraine-lisiecki.com/stack.html and the MIS table: http://www.lorraine-lisiecki.com/LR04_MISboundaries.txt think we oughta follow suit and revise the page MIS data and preceding paragraph? Or keep the existing data and add a new table - or what?108.45.20.126 (talk) 02:09, 28 December 2013 (UTC)

I'd rather add, above the old one. Do you want to do it? Johnbod (talk) 12:48, 28 December 2013 (UTC)

Done it now. Please check over. Johnbod (talk) 15:22, 28 December 2013 (UTC)

Stage 11

When somebody next edits this, please take a look at http://www.whoi.edu/pclift/Ruddiman.pdf, or http://hol.sagepub.com/content/21/5/865.full.pdf+html by Ruddiman, Kutzbach, Vavrus in The Holocene Aug 2011. I think they make a pretty good case (or at least, raise some good red flags) about Stage 11 being considered the best analog of Stage 1., but rather being an outlier in multiple ways. JohnMashey (talk) 22:45, 13 January 2014 (UTC)

Since, uniquely Marine Isotopic Stage 11 has its own article, that is the best initial place for that. I'll copy this section there. I think that "somebody" is you. Johnbod (talk) 01:28, 14 January 2014 (UTC)

book links

• Clark, Webb, Keigwin not yet used Johnbod (talk) 15:12, 11 November 2011 (UTC)

Unreliability of MIS dates

As stated in the article, the International Commission on Stratigraphy has adopted Lisiecki and Raymo's Benthic Stack for MIS dates, and the article cites the dates on her web site. I was puzzled that it gives 14,000 years ago for the start of the Holocene instead of the generally accepted 11,600, and emailed Lisiecki to query it. She replied that 14,000 is based on less well studied time intervals, and 11,600 is preferable. As Mike Christie has pointed out, this shows the danger of relying on raw data. We really need an up to date reliable secondary source. Can anyone suggest one? Dudley Miles (talk) 18:47, 18 September 2015 (UTC)

I think the data in the "Stages" section should be removed; it's essentially primary source data. I agree with Dudley that we need a secondary source for this, but I don't have one on my shelves. Mike Christie (talk - contribs - library) 20:13, 19 September 2015 (UTC)

I disagree; agemodels are bound to change (and hopefully improve) over time. It is useful to have some kind of ball-park reference for the age ranges of marine isotope stages (eg I just used this page for that purpose!). The Gradstein et al timescales can be referred to if you want more precision; but for now, we all know which interglacial is being referred to when we talk about one that "began" at 14ka, even though it didn't exactly! More dubious are the correlations to terrestrial stratigraphic names. The older terrestrial stratigrapic names (before the Anglian, eg "Cromerian") are liable to be "bucket terms" that probably encompass several glacials or interstadials; terrestrial stratigraphic records tend to be incomplete and often poorly chronologically constrained, though still of great interest and utility.Orbitalforam (talk) 14:30, 21 August 2017 (UTC)

Me too. Note that the other date is given in the section below. I'm at something of a loss to see how one set is "primary" and any other "secondary", or indeed what "reliable " means in this contect. If all figures are removed people will just re-add them, on who knows what basis. Johnbod (talk) 14:43, 21 August 2017 (UTC)

There is a much more complete table of correlations to the Marine Isotope Stages in Timeline of glaciation. I believe it can replace the two lists appearing in the current article.216Kleopatra (talk) 06:20, 1 April 2019 (UTC)

The table is useful but in view of the uncertainties I think it is better to add the further information template rather than replace wholesale. Dudley Miles (talk) 07:37, 1 April 2019 (UTC)