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Description

Expansion of the Instrumental Record

Last 2000 years

This image is a comparison of 10 different published reconstructions of mean temperature changes during the last 1000 years. More recent reconstructions are plotted towards the front and in redder colors, older reconstructions appear towards the back and in bluer colors. An instrumental history of temperature is also shown in black. The medieval warm period and little ice age are labeled at roughly the times when they are historically believed to occur, though it is still disputed whether these were truly global or only regional events. The single, unsmoothed annual value for 2004 is also shown for comparison. ( Image:Instrumental Temperature Record.png shows how 2004 relates to other recent years). This image shows the instrumental record of global average temperatures as compiled by the Climatic Research Unit of the University of East Anglia and the Hadley Centre of the UK Meteorological Office. ... This image shows the instrumental record of global average temperatures as compiled by the Climatic Research Unit of the University of East Anglia and the Hadley Centre of the UK Meteorological Office. ... The instrumental temperature record shows the fluctuations of the temperature of the atmosphere and the oceans since the invention of thermomenters. ... Description Expansion of the last 1000 years Temperature variations during the preceeding 12000 years. ... Description Expansion of the last 1000 years Temperature variations during the preceeding 12000 years. ... The Medieval Warm Period (MWP) or Medieval Climate Optimum was an unusually warm period during the European Medieval period, lasting from about the 10th century to about the 14th century. ... The Little Ice Age brought bitterly cold winters to many parts of the world, but is most thoroughly documented in Europe and North America. ... This image shows the instrumental record of global average temperatures as compiled by the Climatic Research Unit of the University of East Anglia and the Hadley Centre of the UK Meteorological Office. ...

For the purposes of this comparison, the author is agnostic as to which, if any, of the reconstructions of global mean temperature is an accurate reflection of temperature fluctuations during the last 1000 years. However, since this plot is a fair representation of the range of reconstructions appearing in the published scientific literature, it is likely that such reconstructions, accurate or not, will play a significant role in the ongoing discussions of global climate change and global warming. Variations in CO2, temperature and dust from the Vostok ice core over the last 400 000 years The term climate change is used to refer to changes in the Earths global climate or regional climates. ... Global mean surface temperatures 1856-2004 Mean temperature anomalies during the period 1995 to 2004 with respect to the average temperatures from 1940 to 1980 Global warming is a term used to describe the increase over time of the average temperature of the Earths atmosphere and oceans. ...

For each reconstruction, the raw data has been decadally smoothed with a σ = 5 yr Gaussian weighted moving average. Also, each reconstruction was adjusted so that its mean matched the mean of the instrumental record during the period of overlap. The variance (i.e. the scale of fluctuations) was not adjusted (except in one case noted below).

Except as noted below, all original data for this comparison comes from [1] and links therein. It should also be noted that many reconstructions of past climate report substantial error bars, which are not represented on this figure.

Reconstructions

The reconstructions used, in order from oldest to most recent publication are:

1. (dark blue 1000-1991): P.D. Jones, K.R. Briffa, T.P. Barnett, and S.F.B. Tett (1998). "High-resolution Palaeoclimatic Records for the last Millennium: Interpretation, Integration and Comparison with General Circulation Model Control-run Temperatures". The Holocene 8:455-471.
2. (blue 1000-1980): M.E. Mann, R.S. Bradley, and M.K. Hughes (1999). "Northern Hemisphere Temperatures During the Past Millennium: Inferences, Uncertainties, and Limitations". Geophysical Research Letters 26 (6): 759-762.
3. (light blue 1000-1965): Crowley and Lowery (2000). "Northern Hemisphere Temperature Reconstruction". Ambio 29:51-54. Modified as published in Crowley (2000). "Causes of Climate Change Over the Past 1000 Years". Science 289:270-277.
4. (lightest blue 1402-1960): K.R. Briffa, T.J. Osborn, F.H. Schweingruber, I.C. Harris, P.D. Jones, S.G. Shiyatov, S.G. and E.A. Vaganov (2001). "Low-frequency temperature variations from a northern tree-ring density network". J. Geophys. Res. 106:2929-2941.
5. (light green 831-1992): J. Esper, E.R. Cook, and F.H. Schweingruber (2002). "Low-Frequency Signals in Long Tree-Ring Chronologies for Reconstructing Past Temperature Variability". Science 295 (5563): 2250-2253.
6. (yellow 200-1980): M.E. Mann and P.D. Jones (2003). "Global Surface Temperatures over the Past Two Millennia". Geophysical Research Letters 30 (15): 1820. DOI:10.1029/2003GL017814.
7. (orange 200-1995): P.D. Jones and M.E. Mann (2004). "Climate Over Past Millennia". Reviews of Geophysics 42:RG2002. DOI:10.1029/2003RG000143
8. (red-orange 1500-1980): S. Huang (2004). "Merging Information from Different Resources for New Insights into Climate Change in the Past and Future". Geophys. Res Lett. 31:L13205. DOI:10.1029/2004GL019781
9. (red 1-1979): A. Moberg, D.M. Sonechkin, K. Holmgren, N.M. Datsenko and W. Karlén (2005). "Highly variable Northern Hemisphere temperatures reconstructed from low- and high-resolution proxy data". Nature 443:613-617. DOI:10.1038/nature03265
10. (dark red 1600-1990): J.H. Oerlemans (2005). "Extracting a Climate Signal from 169 Glacier Records". Science 308:675-677. DOI:10.1126/science.1107046

(black 1856-2004): Instrumental data was jointly compiled by the Climatic Research Unit and the UK Meteorological Office Hadley Centre. Global Annual Average data set TaveGL2v [2] was used. A digital object identifier (or DOI) is a permanent identifier (permalink) given to a World Wide Web file or other Internet document so that if its Internet address changes, users will be redirected to its new address. ... A digital object identifier (or DOI) is a permanent identifier (permalink) given to a World Wide Web file or other Internet document so that if its Internet address changes, users will be redirected to its new address. ... A digital object identifier (or DOI) is a permanent identifier (permalink) given to a World Wide Web file or other Internet document so that if its Internet address changes, users will be redirected to its new address. ... A digital object identifier (or DOI) is a permanent identifier (permalink) given to a World Wide Web file or other Internet document so that if its Internet address changes, users will be redirected to its new address. ... A digital object identifier (or DOI) is a permanent identifier (permalink) given to a World Wide Web file or other Internet document so that if its Internet address changes, users will be redirected to its new address. ... The Climatic Research Unit is a component of the University of East Anglia. ... The new building on the edge of Exeter The Met Office (note: no longer an abbreviation for Meteorological Office but a name in itself), which has its headquarters at Exeter in Devon, is the UKs national weather service. ... The Hadley Centre for Climate Prediction and Research, which is part of the Met Office, provides a focus in the United Kingdom for the scientific issues associated with climate change. ...

Documentation for the most recent update of the CRU/Hadley instrumental data set appears in: P.D. Jones and A. Moberg (2003). "Hemispheric and large-scale surface air temperature variations: An extensive revision and an update to 2001". Journal of Climate 16:206-223.

Copyright

The original version of this figure was prepared by Dragons flight from publicly available data. The figure may be used under the GFDL. GFDL redirects here. ...

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. Subject to disclaimers.

Download high resolution version (720x720, 40 KB) File links The following pages link to this file: GNU Free Documentation License GNU Lesser General Public License User talk:Space Cadet User talk:Jeronimo User talk:Sandos Image:Sable. ...

Notes

1. Data from Moberg et al. was taken directly from the supplemental information accompanying the Nature article.
2. Data for Oerlemans was provided by William M. Connolley.
3. Esper et al. reported only fluctuations in "arbitrary" units, so the variance in this record was rescaled to match the variance during the period of overlap with the instrumental record.
4. When a paper included mulitple reconstructions, the global annually average temperature data was used. If this was not reported, then Northern Hemisphere annually averaged data was used.
5. Four records appearing at [3] were not used in preparing this graph for the following reasons:
   1. Mann et al. 98 was not included because Mann et al. 99 extended and updated that record.
   2. Briffa et al. 98 was not included because Briffa et al. 2001 extended and updated that record.
   3. Pollack et al. 98 was not included because the reported data was not found to be in a form that allowed for easy replotting.
   4. Mann et al. 2000 was not used because it did not included an original reconstruction covering at least the Northern Hemisphere.

Use

(William M. Connolley 10:30, 15 Feb 2005 (UTC)) A note: I have used this at http://www.realclimate.org/index.php?p=122

Also used in http://www.realclimate.org/index.php?p=121

File history

Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version.
Click on date to download the file or see the image uploaded on that date. Earth, also known as the Earth, Terra, and (mostly in the 19th century) Tellus, is the third-closest planet to the Sun. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... Description Expanded record of instrumental temperatures showing recent global warming This figure shows the last 25 years of globally averaged instrumental surface temperature measurements according to data collected by the Hadley Centre of the UK Meteorological Office and the Climatic Research Unit of the University of East Anglia. ... This image shows the instrumental record of global average temperatures as compiled by the Climatic Research Unit of the University of East Anglia and the Hadley Centre of the UK Meteorological Office. ... Description Expansion of the last 1000 years Temperature variations during the preceeding 12000 years. ... Description Reconstructions of the last 2000 years. ... Description Expanded record of temperature change since the end of the last glacial period Extended record of climate change during the last 5 Myr This figure shows the Antarctic temperature changes during the last several glacial/interglacial cycles of the present ice age and a comparison to changes in global... Description Expansion of changes during the recent sequence of glacials and interglacials This figure shows the climate record of Lisiecki and Raymo (2005) [1] constructed by combining measurements from 57 globally distributed deep sea sediment cores. ... Image File history File links // Description Expanded view of climate change during the last five million years, showing the rapid oscillations in the glacial state. ... Description This figure shows the long-term evolution of oxygen isotope ratios during the Phanerozoic eon as measured in fossils, reported by Veizer et al. ... The temperature record shows the fluctuations of the temperature of the atmosphere and the oceans through various spans of time. ...

• (del) (cur) 04:34, 5 September 2005 . . Dragons flight (40783 bytes) (Reverted to earlier revision)
• (del) (rev) 03:03, 16 August 2005 . . Andrew pmk (43091 bytes) (compress)
• (del) (rev) 22:34, 11 August 2005 . . Zbzw (67806 bytes) (Reverted to earlier revision)
• (del) (rev) 18:44, 18 March 2005 . . Dragons flight (40783 bytes) (Large Labels)
• (del) (rev) 16:38, 18 March 2005 . . Dragons flight (40573 bytes) (Add new data, improve presentation, smaller file)
• (del) (rev) 02:39, 13 February 2005 . . Dragons flight (68669 bytes) (Slight correction)
• (del) (rev) 01:37, 13 February 2005 . . Dragons flight (68940 bytes) (Correcting Esper et al. placement)
• (del) (rev) 00:27, 13 February 2005 . . Dragons flight (67806 bytes) (A comparison of different reconstructions of mean temperature during the last 1000 years)

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• Temperature record of the past 1000 years
• Talk:Temperature record of the past 1000 years
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• Image:2000 Year Temperature Comparison.png
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• Talk:Global warming/Archive 1