Three charts of global average temperature three respective time periods: 800,000 years, 2,000 years, and 139 years, showing current <a href="https://en.wikipedia.org/wiki/global_warming" class="extiw" title="w:global warming">global warming</a> in the perspective of geologic time.
<p><br><i><b>Suggested text for use in articles:</b></i><br>
● <b>Top chart:</b> Earth's climate has cycled between ice ages and warm interglacial periods, with each cycle taking tens of thousands of years or more.<br>
● <b>Middle chart:</b> Global average temperature was in a cooling trend for thousands of years before fossil fuel based industrialization. Since then, it has increased about a full 1°C—in a time period less than 1/3,000th the width of the top chart.<br>
● <b>Bottom chart:</b> This 1°C increase, commonly called <i>global warming,</i> accelerated since 1980—a period less than 1/20,000th the width of the top chart.
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<center><b><u>SOURCES (and related explanations)</u></b>:</center>
<dl><dd><b>1. Top chart (800,000 years)</b>:
<dl><dd>— Data itself:
<dl><dd><ul><li><a rel="nofollow" class="external free" href="https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/epica_domec/edc3deuttemp2007.txt">https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/epica_domec/edc3deuttemp2007.txt</a></li>
<li><a rel="nofollow" class="external free" href="https://web.archive.org/web/20191014051524/https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/epica_domec/edc3deuttemp2007.txt">https://web.archive.org/web/20191014051524/https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/epica_domec/edc3deuttemp2007.txt</a></li></ul></dd></dl></dd></dl></dd></dl><dl><dd><dl><dd>— Chart is described in NASA "Earth observatory" webpage:
<dl><dd><ul><li><a rel="nofollow" class="external free" href="https://earthobservatory.nasa.gov/features/GlobalWarming/page3.php">https://earthobservatory.nasa.gov/features/GlobalWarming/page3.php</a></li>
<li><a rel="nofollow" class="external free" href="https://web.archive.org/web/20190924011459/https://earthobservatory.nasa.gov/features/GlobalWarming/page3.php">https://web.archive.org/web/20190924011459/https://earthobservatory.nasa.gov/features/GlobalWarming/page3.php</a></li></ul></dd></dl></dd>
<dd>— Source provides 5,788 points of data for the 800,000 year period, with <i>many</i> more points for recent millennia than for ancient millennia. Accordingly, uploader RCraig09 averaged readings for each millennium to create a list of 800 data points (one for each millennium), which was used in Microsoft Excel to generate the top chart.<br></dd>
<dd>— Actual data is provided in expandable text, below.</dd></dl></dd></dl><p><span style="color:green" title="green"><i><b>Description from data source page:</b></i></span><br><span style="color:green" title="green">— "NAME OF DATA SET:  EPICA Dome C Ice Core 800KYr Deuterium Data and Temperature Estimates<br>
— LAST UPDATE: 11/26/2007 (Replaced age model. This file now includes EDC3 age model.  Previous version of this file dated 10/16/2007 erroneously included the older EDC1-EDC2 age model)<br>
— CONTRIBUTOR: ValÈrie Masson-Delmotte, LSCE/IPSL IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2007-091<br>
— SUGGESTED DATA CITATION: Jouzel, J., et al.  2007. EPICA Dome C Ice Core 800KYr Deuterium Data and Temperature Estimates. 
IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2007-091. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA.<br>
— ORIGINAL REFERENCE: Jouzel, J., V. Masson-Delmotte, O. Cattani, G. Dreyfus, S. Falourd, G. Hoffmann, B. Minster, J. Nouet, J.M. Barnola, J. Chappellaz, J.C. Gallet, S. Johnsen, M. Leuenberger, L. Loulergue, D. Luethi, H. Oerter, F. Parrenin, G. Raisbeck, D. Raynaud, A. Schilt, J. R. Souchez, R. Spahni, B. Stauffer, J.P. Steffensen, B. Stenni, T.F. Stocker, J.L. Tison, M. Werner, and E.W. Wolff.  2007. Orbital and Millennial Antarctic Climate Variability over the Past 800,000 Years. <i>Science,</i> Vol. 317, No. 5839, pp.793-797, 10 August 2007.<br>
— ABSTRACT: A high-resolution deuterium profile is now available along the entire European Project for Ice Coring in Antarctica Dome C ice core, extending this climate record back to marine isotope stage 20.2, ~800,000 years ago. Experiments performed with an atmospheric general circulation model including water isotopes support its temperature interpretation. We assessed the general 
events and their smoothed Antarctic counterparts for this Dome C record, which reveals the presence of such features with similar 
during previous glacial periods. We suggest that the interplay between obliquity and precession accounts for the variable intensity 
interglacial periods in ice core records.<br>
— GEOGRAPHIC REGION: Antarctica<br>
— PERIOD OF RECORD:  803 KYrBP - present<br>
— ...Column 3: EDC3 age scale (years before year 1950)<br>
— ...Column 5: Temperature estimate (temperature difference from the average of the last 1000 years)</span>"
</p>
<dl><dd><b>2. Middle chart (2,000 years)</b>:
<dl><dd><dl><dd><ul><li>Wikimedia image file <a href="//commons.wikimedia.org/wiki/File:Temperature_reconstruction_last_two_millennia.svg" title="File:Temperature reconstruction last two millennia.svg">File:Temperature reconstruction last two millennia.svg</a> by <a href="//commons.wikimedia.org/wiki/User_talk:Femkemilene" class="mw-redirect" title="User talk:Femkemilene">User talk:Femkemilene</a></li></ul></dd></dl></dd></dl></dd></dl><dl><dd><b>3. Bottom chart (139 years)</b>:
<dl><dd><dl><dd><ul><li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20190726160612/https://www.ncdc.noaa.gov/cag/global/time-series/globe/land_ocean/12/12/1880-2019">Climate at a Glance / Global Time Series</a>. <i>ncdc.noaa.gov</i>. <a href="https://en.wikipedia.org/wiki/National_Oceanic_and_Atmospheric_Administration" class="extiw" title="w:National Oceanic and Atmospheric Administration">NOAA</a> (National Centers for Environmental Information; National Climatic Data Center) (December 2018). Archived from <a rel="nofollow" class="external text" href="https://www.ncdc.noaa.gov/cag/global/time-series/globe/land_ocean/12/12/1880-2019">the original</a> on <span class="mw-formatted-date" title="2019-07-26">26 July 2019</span>. Retrieved on <span class="mw-formatted-date" title="2019-07-27">27 July 2019</span>.</li></ul><dl><dd>— In the NOAA wab page, choose 12-Month timescale, December, 1880-2019, <b>Global</b>, Land and Ocean, <b>Plot</b>.</dd>
<dd>— Data uses 1901-2000 base period (=0°C in the chart).</dd></dl><ul><li>Actual data for this chart is provided in expandable text, below.</li>
<li>FYI: Data, adjusted for a different base period, is used in the top half of uploader RCraig09's other image file: <a href="//commons.wikimedia.org/wiki/File:20190727_COMPARE_warming_stripes_-_Global_vs_Caribbean_1910-2018_(ref_1910-2000).png" title="File:20190727 COMPARE warming stripes - Global vs Caribbean 1910-2018 (ref 1910-2000).png">File: 20190727 COMPARE warming stripes - Global vs Caribbean 1910-2018 (ref 1910-2000).png</a></li></ul></dd></dl></dd></dl></dd></dl>
<a href="//commons.wikimedia.org/wiki/User:RCraig09" title="User:RCraig09">RCraig09</a>
CC BY-SA 4.0
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