Unexpected Changes to the Global Methane Budget over the Past 2000 Years

@article{Ferretti2005UnexpectedCT,
  title={Unexpected Changes to the Global Methane Budget over the Past 2000 Years},
  author={Dominic Francesco Ferretti and J. B. Miller and J. W. C. White and David M. Etheridge and Keith R. Lassey and David C. Lowe and C. M. MacFarling Meure and Mark F. Dreier and Cathy M. Trudinger and Tas D. van Ommen and Ray L. Langenfelds},
  journal={Science},
  year={2005},
  volume={309},
  pages={1714 - 1717}
}
We report a 2000-year Antarctic ice-core record of stable carbon isotope measurements in atmospheric methane (δ13CH4). Large δ13CH4 variations indicate that the methane budget varied unexpectedly during the late preindustrial Holocene (circa 0 to 1700 A.D.). During the first thousand years (0 to 1000 A.D.), δ13CH4 was at least 2 per mil enriched compared to expected values, and during the following 700 years, an about 2 per mil depletion occurred. Our modeled methane source partitioning implies… 

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References

SHOWING 1-10 OF 27 REFERENCES

Changes in the global atmospheric methane budget over the last decades inferred from13C and D isotopic analysis of Antarctic firn air

The atmospheric trend of methane isotopic ratios since the mid-20th century has been reconstructed from Antarctic firn air. High volume air samples were extracted at several depth levels at two sites

Atmospheric methane between 1000 A.D. and present: Evidence of anthropogenic emissions and climatic variability

Atmospheric methane mixing ratios from 1000 A.D. to present are measured in three Antarctic ice cores, two Greenland ice cores, the Antarctic firn layer, and archived air from Tasmania, Australia.

The trend in atmospheric methane δ13C and implications for isotopic constraints on the global methane budget

A recent paper by Tans [1997] has drawn attention to the isotopic disequilibrium that inevitably prevails when atmospheric methane is not in steady state with its sources, noting in particular the

Holocene biomass burning and global dynamics of the carbon cycle.

Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica

The recent completion of drilling at Vostok station in East Antarctica has allowed the extension of the ice record of atmospheric composition and climate to the past four glacial–interglacial cycles.

The Anthropogenic Greenhouse Era Began Thousands of Years Ago

The anthropogenic era is generally thought to have begun 150 to 200 years ago, when the industrial revolution began producing CO2 andCH4 at rates sufficient to alter their compositions in the

Atmospheric methane in the recent and ancient atmospheres Concentrations, trends, and interhemispheric gradient

The concentrations of methane in the old and ancient atmospheres of the earth can be deduced by analyzing the air in bubbles embedded in polar ice cores. Upon analyzing some 80 ice core samples from

The 1991–1992 atmospheric methane anomaly: Southern hemisphere 13C decrease and growth rate fluctuations

Measurements of atmospheric methane from 1989–1996 at Baring Head, New Zealand, and at Scott Base, Antarctica show a seasonal cycle in the mixing ratio with a peak to peak amplitude of 28 ppb. This

A history of δ13C in atmospheric CH4 from the Cape Grim Air Archive and Antarctic firn air

Marine (baseline) air from Cape Grim (41°S), collected and archived in high-pressure metal containers, provides a history of δ13C in atmospheric methane from 1978. A similar history is obtained from