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

  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},
  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… 

Changing boreal methane sources and constant biomass burning during the last termination

An ice core record of carbon isotopic ratios in methane over the entire last glacial–interglacial transition shows that the carbon in atmospheric methane was isotopically much heavier in cold climate periods, and the atmospheric lifetime of methane is reduced duringcold climate periods.

Multidecadal variability of atmospheric methane, 1000–1800 C.E.

[1] We present a new high-precision, high-resolution record of atmospheric methane from the West Antarctic Ice Sheet (WAIS) Divide ice core covering 1000–1800 C.E., a time period known as the late

Atmospheric methane control mechanisms during the early Holocene

Abstract. Understanding processes controlling the atmospheric methane (CH4) mixing ratio is crucial to predict and mitigate future climate changes in this gas. Despite recent detailed studies of the

Constraining past global tropospheric methane budgets with carbon and hydrogen isotope ratios in ice

  • M. WhiticarH. Schaefer
  • Environmental Science, Geography
    Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
  • 2007
The first methane budgets for the late glacial period that are constrained by dual stable isotopes are presented and indicate that the Younger Dryas (YD) and Preindustrial Holocene have methane that is 13C- and 2H-enriched, relative to Modern.

Ice Record of δ13C for Atmospheric CH4 Across the Younger Dryas-Preboreal Transition

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Glacial/interglacial wetland, biomass burning, and geologic methane emissions constrained by dual stable isotopic CH4 ice core records

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A 21st-century shift from fossil-fuel to biogenic methane emissions indicated by 13CH4

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Reconstruction of Paleofire Emissions Over the Past Millennium From Measurements of Ice Core Acetylene

Acetylene is a short‐lived trace gas produced during combustion of fossil fuels, biomass, and biofuels. Biomass burning is likely the only major source of acetylene in the preindustrial atmosphere,



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

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

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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