File:Five Myr Climate Change.svg
Original file (SVG file, nominally 1,024 × 372 pixels, file size: 68 KB)
Summary
| Description |
Reconstruction of the past 5 million years of climate history, based on oxygen isotope fractionation (serving as a proxy for the total global mass of glacial ice sheets). See the discussion below for a summary of the methods and models used. Català: Reconstrucció dels darrers cinc milions d'anys de la història del clima, basada en el fraccionament d'isòtops d'oxigen (que serveix com a proxy de la massa global total de les capes de gel glacials). Русский: Реконструкция истории климата за последние пять миллионов лет на основе значений δ18O. Эта величина, производная от отношения изотпоов кислорода 18O и 16O (см. δ18O (en)), выступает в роли заменителя (прокси) глобальной температуры.
Note that the resolution of the graph has suffered in the conversion from png to svg. Use the original png if possible. Also note that in 2010, User:SeL media switched the orientation of the time axis and the vertical axes, apparently without discussion, and some descriptions of the image may refer to the older version, resulting in confusion of 'right' and 'left' in the image. |
| Date | (svg file 2009-02-07) |
| Source | svg-version of Five_Myr_Climate_Change.png; original image by User:Dragons flight, based on data (figure 4?) from Lisiecki and Raymo (2005) |
| Author | Dragons flight (Robert A. Rohde), svg by Jo |
| Permission (Reusing this file) |
This figure was prepared by Robert A. Rohde based on published data and is incorporated into the Global Warming Art project. |
| Other versions |
Five_Myr_Climate_Change.png, Derivative works of this file: Five Myr Climate Change-ml.svg, Five Myr Climate Change (de), Five Myr Climate Change (fr) File:Five Myr Climate Change.svg has 3 translations.
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Discussion
This figure shows the climate record of Lisiecki and Raymo (2005) [1] constructed by combining measurements from 57 globally distributed deep sea sediment cores. The measured quantity is oxygen isotope fractionation (δ18O) in benthic foraminifera, which serves as a proxy for the total global mass of glacial ice sheets.
Lisiecki and Raymo constructed this record by first applying a computer aided process of adjusting individual "wiggles" in each sediment core to have the same alignment (i.e. wiggle matching). Then the resulting stacked record is orbitally tuned by adjusting the positions of peaks and valleys to fall at times consistent with an orbitally driven ice model (see: Milankovitch cycles). Both sets of these adjustments are constrained to be within known uncertainties on sedimentation rates and consistent with independently dated tie points (if any). Constructions of this kind are common, however they presume that ice sheets are orbitally driven, and hence data such as this can not be used in establishing the existence of such a relationship.
The observed isotope variations are very similar in shape to the temperature variations recorded at Vostok, Antarctica during the 420 kyr for which that record exists. Hence the right hand scale of the figure was established by fitting the reported temperature variations at Vostok (Petit et al. 1999) to the observed isotope variations. Hence, this temperature scale should be regarded as approximate and its magnitude is only representative of Vostok changes. In particular, temperature changes at polar sites, such as Vostok, frequently exceed the changes observed in the tropics or in the global average. A horizontal line at 0 °C indicates modern temperatures (circa 1950).
Labels are added to indicate regions where 100 kyr and 41 kyr cyclicity is observed. These periodicities match periodic changes in Earth's orbital eccentricity and obliquity respectively, and have been previously established by other studies (not relying on orbital tuning). For discussion of how such orbital changes might drive climate change, see Milankovitch cycles.
References
- Lisiecki, L. E., and M. E. Raymo (2005), A Pliocene-Pleistocene stack of 57 globally distributed benthic δ18O records, Paleoceanography, 20, PA1003, doi:10.1029/2004PA001071; data: doi:10.1594/PANGAEA.704257. — bundled as {{cite DOI|10.1029/2004PA001071}}
- Petit J.R., Jouzel J., Raynaud D., Barkov N.I., Barnola J.M., Basile I., Bender M., Chappellaz J., Davis J., Delaygue G., Delmotte M., Kotlyakov V.M., Legrand M., Lipenkov V., Lorius C., Pépin L., Ritz C., Saltzman E., Stievenard M. (1999) Climate and Atmospheric History of the Past 420,000 years from the Vostok Ice Core, Antarctica, Nature, 399, pp.429-436, doi:10.1038/20859.
Licensing
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Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License. |
  
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This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. | |
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| This licensing tag was added to this file as part of the GFDL licensing update. |
| Dragons flight's Temperature Record Series |
| This figure is part of a series of plots created by Dragons flight to illustrate changes in Earth's temperature and climate across many different time scales. |
| Time Period: 25 yrs | 150 yrs | 1 kyr | 2 kyr | 12 kyr | 450 kyr | 5 Myr | 65 Myr | 500 Myr |
| For articles related to this topic see: Temperature record |
File history
Click on a date/time to view the file as it appeared at that time.
| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 20:06, 6 January 2024 | | 1,024 × 372 (68 KB) | wikimediacommons>Ivsetaki | Added a Russian translation. |
File usage
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