This graph features atmospheric temperature and methane levels, a powerful greehouse gas, that combine measurements from Antarctica ice core data as far back as 800,000 years up to the most recent measurements averaged from a global network of air sampling sites. We encourage you to embed this graph directly into your website. The graph is fully customizable to fit your websites' look and feel. This is a free service, but we do ask for a donation if you find this useful. This is a project of the 2 Degrees Institute, a non-profit organization.
Changes in past atmospheric methane concentrations are determined by measuring the composition of air trapped in ice
cores from Antarctica. So far, the Antarctic Vostok and EPICA
Dome C ice cores have provided a composite record of atmospheric
methane levels over the past 800,000 years.
Credits:
Loulergue, L., A. Schilt, R. Spahni, V. Masson-Delmotte, T. Blunier,
B. Lemieux, J.-M. Barnola, D. Raynaud, T.F. Stocker, and J. Chappellaz. 2008.
Orbital and millennial-scale features of atmospheric CH4 over the past
800,000 years.
Nature, Vol. 453, pp. 383-386, 15 May 2008. doi:10.1038/nature06950
Learn about temperature data sources.
The methane ice core records for this time period are derived from three cores
obtained from Law Dome, East Antarctica from 1987 to 1993, and samples from
the Eurocore and GISP2 ice cores from the Summit region, Greenland.
The Law Dome sites satisfy many of the desirable characteristics of an ideal
ice core site for atmospheric reconstructions including negligible melting
of the ice sheet surface, low concentrations of impurities, regular stratigraphic
layering undisturbed at the surface by wind or at depth by ice flow, and high
snow accumulation rate.
Credits:
Etheridge, D.M., et al., 2002
Ice Core, Firn Air and Archived Air Atmospheric Methane Concentration Data
IGBP PAGES/World Data Center for Paleoclimatology
Data Contribution Series #2002-039.
NOAA/NGDC Paleoclimatology Program, Boulder CO, USA.
Etheridge, D. M., Steele, L. P., Francey, R. J., and
Langenfelds, R. L., 1998, Atmospheric methane between 1000 A.D. and present:
Evidence of anthropogenic emissions and climatic variability
J. Geophys. Res. Vol. 103, No. D13, p. 15,979 (98JD00923)
Learn about temperature data sources.
Globally-averaged, monthly mean atmospheric methane abundance is determined from marine surface sites. The Global Monitoring Division of NOAA's Earth System Research Laboratory has measured methane since 1983 at a globally distributed network of air sampling sites.
Credits: Ed Dlugokencky, NOAA/ESRL (www.esrl.noaa.gov/gmd/ccgg/trends_ch4/)
Learn about temperature data sources.
Dr. Pieter Tans
NOAA's Earth System Research Laboratory
Dr. Jeremy Shakun
Boston College
Dr. Geoff Dutton
NOAA's Earth System Research Laboratory
Dr. Ed Dlugokencky
NOAA's Earth System Research Laboratory
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