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NAKAZAWA T. Current understanding of the global cycling of carbon dioxide, methane, and nitrous oxide. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2020; 96:394-419. [PMID: 33177295 PMCID: PMC7725657 DOI: 10.2183/pjab.96.030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Accepted: 08/31/2020] [Indexed: 06/11/2023]
Abstract
To address the climate change caused by anthropogenic emissions of greenhouse gases into the atmosphere, it is essential to understand and quantitatively elucidate their cycling on the Earth's surface. This paper first presents an overview of the global cycling of three greenhouse gases, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), followed by a description of their variations in the atmosphere. This paper then presents the recent global budgets of these greenhouse gases estimated using two different approaches, top-down and bottom-up. Discussions on our current knowledge regarding the global cycling of the three gases are also presented.
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Schilt A, Brook EJ, Bauska TK, Baggenstos D, Fischer H, Joos F, Petrenko VV, Schaefer H, Schmitt J, Severinghaus JP, Spahni R, Stocker TF. Isotopic constraints on marine and terrestrial N2O emissions during the last deglaciation. Nature 2015; 516:234-7. [PMID: 25503236 DOI: 10.1038/nature13971] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 10/13/2014] [Indexed: 11/09/2022]
Abstract
Nitrous oxide (N2O) is an important greenhouse gas and ozone-depleting substance that has anthropogenic as well as natural marine and terrestrial sources. The tropospheric N2O concentrations have varied substantially in the past in concert with changing climate on glacial-interglacial and millennial timescales. It is not well understood, however, how N2O emissions from marine and terrestrial sources change in response to varying environmental conditions. The distinct isotopic compositions of marine and terrestrial N2O sources can help disentangle the relative changes in marine and terrestrial N2O emissions during past climate variations. Here we present N2O concentration and isotopic data for the last deglaciation, from 16,000 to 10,000 years before present, retrieved from air bubbles trapped in polar ice at Taylor Glacier, Antarctica. With the help of our data and a box model of the N2O cycle, we find a 30 per cent increase in total N2O emissions from the late glacial to the interglacial, with terrestrial and marine emissions contributing equally to the overall increase and generally evolving in parallel over the last deglaciation, even though there is no a priori connection between the drivers of the two sources. However, we find that terrestrial emissions dominated on centennial timescales, consistent with a state-of-the-art dynamic global vegetation and land surface process model that suggests that during the last deglaciation emission changes were strongly influenced by temperature and precipitation patterns over land surfaces. The results improve our understanding of the drivers of natural N2O emissions and are consistent with the idea that natural N2O emissions will probably increase in response to anthropogenic warming.
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Affiliation(s)
- Adrian Schilt
- 1] College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, Oregon 97331, USA [2] Climate and Environmental Physics, Physics Institute, and Oeschger Centre for Climate Change Research, University of Bern, 3012 Bern, Switzerland
| | - Edward J Brook
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, Oregon 97331, USA
| | - Thomas K Bauska
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, Oregon 97331, USA
| | - Daniel Baggenstos
- Scripps Institution of Oceanography, University of California, San Diego, California 92037, USA
| | - Hubertus Fischer
- Climate and Environmental Physics, Physics Institute, and Oeschger Centre for Climate Change Research, University of Bern, 3012 Bern, Switzerland
| | - Fortunat Joos
- Climate and Environmental Physics, Physics Institute, and Oeschger Centre for Climate Change Research, University of Bern, 3012 Bern, Switzerland
| | - Vasilii V Petrenko
- Department of Earth and Environmental Sciences, University of Rochester, Rochester, New York 14627, USA
| | - Hinrich Schaefer
- National Institute of Water and Atmospheric Research, Wellington 6021, New Zealand
| | - Jochen Schmitt
- Climate and Environmental Physics, Physics Institute, and Oeschger Centre for Climate Change Research, University of Bern, 3012 Bern, Switzerland
| | - Jeffrey P Severinghaus
- Scripps Institution of Oceanography, University of California, San Diego, California 92037, USA
| | - Renato Spahni
- Climate and Environmental Physics, Physics Institute, and Oeschger Centre for Climate Change Research, University of Bern, 3012 Bern, Switzerland
| | - Thomas F Stocker
- Climate and Environmental Physics, Physics Institute, and Oeschger Centre for Climate Change Research, University of Bern, 3012 Bern, Switzerland
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Yeung LY, Young ED, Schauble EA. Measurements of18O18O and17O18O in the atmosphere and the role of isotope-exchange reactions. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012jd017992] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Mitchell LE, Brook EJ, Sowers T, McConnell JR, Taylor K. Multidecadal variability of atmospheric methane, 1000–1800 C.E. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jg001441] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Northern peatland initiation lagged abrupt increases in deglacial atmospheric CH4. Proc Natl Acad Sci U S A 2011; 108:4748-53. [PMID: 21368146 DOI: 10.1073/pnas.1013270108] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Peatlands are a key component of the global carbon cycle. Chronologies of peatland initiation are typically based on compiled basal peat radiocarbon (14C) dates and frequency histograms of binned calibrated age ranges. However, such compilations are problematic because poor quality 14C dates are commonly included and because frequency histograms of binned age ranges introduce chronological artefacts that bias the record of peatland initiation. Using a published compilation of 274 basal 14C dates from Alaska as a case study, we show that nearly half the 14C dates are inappropriate for reconstructing peatland initiation, and that the temporal structure of peatland initiation is sensitive to sampling biases and treatment of calibrated 14C dates. We present revised chronologies of peatland initiation for Alaska and the circumpolar Arctic based on summed probability distributions of calibrated 14C dates. These revised chronologies reveal that northern peatland initiation lagged abrupt increases in atmospheric CH4 concentration at the start of the Bølling-Allerød interstadial (Termination 1A) and the end of the Younger Dryas chronozone (Termination 1B), suggesting that northern peatlands were not the primary drivers of the rapid increases in atmospheric CH4. Our results demonstrate that subtle methodological changes in the synthesis of basal 14C ages lead to substantially different interpretations of temporal trends in peatland initiation, with direct implications for the role of peatlands in the global carbon cycle.
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Kunasek SA, Alexander B, Steig EJ, Sofen ED, Jackson TL, Thiemens MH, McConnell JR, Gleason DJ, Amos HM. Sulfate sources and oxidation chemistry over the past 230 years from sulfur and oxygen isotopes of sulfate in a West Antarctic ice core. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010jd013846] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Weber SL, Drury AJ, Toonen WHJ, van Weele M. Wetland methane emissions during the Last Glacial Maximum estimated from PMIP2 simulations: Climate, vegetation, and geographic controls. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd012110] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Petrenko VV, Smith AM, Brook EJ, Lowe D, Riedel K, Brailsford G, Hua Q, Schaefer H, Reeh N, Weiss RF, Etheridge D, Severinghaus JP. 14
CH
4
Measurements in Greenland Ice: Investigating Last Glacial Termination CH
4
Sources. Science 2009; 324:506-8. [DOI: 10.1126/science.1168909] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Vasilii V. Petrenko
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093, USA
| | - Andrew M. Smith
- Australian Nuclear Science and Technology Organisation (ANSTO), Private Mail Box 1, Menai, NSW 2234, Australia
| | - Edward J. Brook
- Department of Geosciences, Oregon State University, Corvallis, OR 97331, USA
| | - Dave Lowe
- National Institute of Water and Atmospheric Research Ltd., Post Office Box 14901, Kilbirnie, 301 Evans Bay Parade, Wellington, New Zealand
| | - Katja Riedel
- National Institute of Water and Atmospheric Research Ltd., Post Office Box 14901, Kilbirnie, 301 Evans Bay Parade, Wellington, New Zealand
| | - Gordon Brailsford
- National Institute of Water and Atmospheric Research Ltd., Post Office Box 14901, Kilbirnie, 301 Evans Bay Parade, Wellington, New Zealand
| | - Quan Hua
- Australian Nuclear Science and Technology Organisation (ANSTO), Private Mail Box 1, Menai, NSW 2234, Australia
| | - Hinrich Schaefer
- National Institute of Water and Atmospheric Research Ltd., Post Office Box 14901, Kilbirnie, 301 Evans Bay Parade, Wellington, New Zealand
| | - Niels Reeh
- DTU Space, National Space Institute, Technical University of Denmark, Ørsteds Plads, Building 348, DK-2800 Kongens Lyngby, Denmark
| | - Ray F. Weiss
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093, USA
| | - David Etheridge
- Commonwealth Scientific and Industrial Research Organisation, Marine and Atmospheric Research, Private Mail Box 1, Aspendale, VIC 3195, Australia
| | - Jeffrey P. Severinghaus
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093, USA
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Kunasek SA, Alexander B, Steig EJ, Hastings MG, Gleason DJ, Jarvis JC. Measurements and modeling of Δ17O of nitrate in snowpits from Summit, Greenland. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008jd010103] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Whiticar M, Schaefer H. Constraining past global tropospheric methane budgets with carbon and hydrogen isotope ratios in ice. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2007; 365:1793-828. [PMID: 17513274 DOI: 10.1098/rsta.2007.2048] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Upon closer inspection, the classical view of the synchronous relationship between tropospheric methane mixing ratio and Greenland temperature observed in ice samples reveals clearly discernable variations in the magnitude of this response during the Late Pleistocene (<50kyr BP). During the Holocene this relationship appears to decouple, indicating that other factors have modulated the methane budget in the past 10kyr BP. The delta13CH4 and deltaD-CH4 of tropospheric methane recorded in ice samples provide a useful constraint on the palaeomethane budget estimations. Anticipated changes in palaeoenvironmental conditions are recorded as changes in the isotope signals of the methane precursors, which are then translated into past global delta13CH4 and deltaD-CH4 signatures. We present the first methane budgets for the late glacial period that are constrained by dual stable isotopes. The overall isotope variations indicate that the Younger Dryas (YD) and Preindustrial Holocene have methane that is 13C- and 2H-enriched, relative to Modern. The shift is small for delta13CH4 (approx. 1 per thousand) but greater for deltaD-CH4 (approx. 9 per thousand). The YD delta13CH4-deltaD-CH4 record shows a remarkable relationship between them from 12.15 to 11.52kyr BP. The corresponding C- and H-isotope mass balances possibly indicate fluctuating emissions of thermogenic gas. This delta13CH4-deltaD-CH4 relationship breaks down during the YD-Preboreal transition. In both age cases, catastrophic releases of hydrates with Archaeal isotope signatures can be ruled out. Thermogenic clathrate releases are possible during the YD period, but so are conventional natural gas seepages.
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Affiliation(s)
- Michael Whiticar
- School of Earth and Ocean Sciences, University of Victoria, Victoria, British Columbia, Canada.
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Worton DR, Sturges WT, Gohar LK, Shine KP, Martinerie P, Oram DE, Humphrey SP, Begley P, Gunn L, Barnola JM, Schwander J, Mulvaney R. Atmospheric trends and radiative forcings of CF4 and C2F6 inferred from firn air. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2007; 41:2184-9. [PMID: 17438761 DOI: 10.1021/es061710t] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The atmospheric histories of two potent greenhouse gases, tetrafluoromethane (CF4) and hexafluoroethane (C2F6), have been reconstructed for the 20th century based on firn air measurements from both hemispheres. The reconstructed atmospheric trends show that the mixing ratios of both CF4 and C2F6 have increased during the 20th century by factors of approximately 2 and approximately 10, respectively. Initially, the increasing mixing ratios coincided with the rise in primary aluminum production. However, a slower atmospheric growth rate for CF4 appears to be evident during the 1990s, which supports recent aluminum industry reports of reduced CF4 emissions. This work illustrates the changing relationship between CF4 and C2F6 that is likely to be largely the result of both reduced emissions from the aluminum industry and faster growing emissions of C2F6 from the semiconductor industry. Measurements of C2F6 in the older firn air indicate a natural background mixing ratio of <0.3 parts per trillion (ppt), demonstrating that natural sources of this gas are negligible. However, CF4 was deduced to have a preindustrial mixing ratio of 34 -1 ppt (-50% of contemporary levels). This is in good agreement with the previous work of Harnisch et al. (18) and provides independent confirmation of their results. As a result of the large global warming potentials of CF4 and C2F6, these results have important implications for radiative forcing calculations. The radiative forcings of CF4 and C2F6 are shown to have increased over the past 50 years to values in 2001 of 4.1 x 10(-3) Wm(-2) and 7.5 x 10(-4) Wm(-2), respectively, relative to preindustrial concentrations. These forcings are small compared to present day forcings due to the major greenhouse gases but, if the current trends continue, they will continue to increase since both gases have essentially infinite lifetimes. There is, therefore, a large incentive to reduce perfluorocarbon emissions such that through the implementation of the Kyoto Protocol, the atmospheric growth rates may decline in the future.
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Affiliation(s)
- David R Worton
- School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
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Sowers T. Late Quaternary Atmospheric CH4 Isotope Record Suggests Marine Clathrates Are Stable. Science 2006; 311:838-40. [PMID: 16469923 DOI: 10.1126/science.1121235] [Citation(s) in RCA: 159] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
One explanation for the abrupt increases in atmospheric CH4, that occurred repeatedly during the last glacial cycle involves clathrate destabalization events. Because marine clathrates have a distinct deuterium/hydrogen (D/H) isotope ratio, any such destabilization event should cause the D/H ratio of atmospheric CH4 (deltaD(CH4)) to increase. Analyses of air trapped in the ice from the second Greenland ice sheet project show stable and/or decreasing deltaD(CH4) values during the end of the Younger and Older Dryas periods and one stadial period, suggesting that marine clathrates were stable during these abrupt warming episodes. Elevated glacial deltaD(CH4) values may be the result of a lower ratio of net to gross wetland CH4 emissions and an increase in petroleum-based emissions.
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Affiliation(s)
- Todd Sowers
- Department of Geosciences and the Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA 16802, USA.
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Alexander B. Impact of preindustrial biomass-burning emissions on the oxidation pathways of tropospheric sulfur and nitrogen. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2003jd004218] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Sowers T, Alley RB, Jubenville J. Ice core records of atmospheric N2O covering the last 106,000 years. Science 2003; 301:945-8. [PMID: 12920293 DOI: 10.1126/science.1085293] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Paleoatmospheric records of trace-gas concentrations recovered from ice cores provide important sources of information on many biogeochemical cycles involving carbon, nitrogen, and oxygen. Here, we present a 106,000-year record of atmospheric nitrous oxide (N2O) along with corresponding isotopic records spanning the last 30,000 years, which together suggest minimal changes in the ratio of marine to terrestrial N2O production. During the last glacial termination, both marine and oceanic N2O emissions increased by 40 +/- 8%. We speculate that our records do not support those hypotheses that invoke enhanced export production to explain low carbon dioxide values during glacial periods.
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Affiliation(s)
- Todd Sowers
- Department of Geosciences and the EMS Environment Institute, Pennsylvania State University, UniversityPark, PA 16802, USA.
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Dentener F. Interannual variability and trend of CH4lifetime as a measure for OH changes in the 1979–1993 time period. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002jd002916] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Lelieveld J, Peters W, Dentener FJ, Krol MC. Stability of tropospheric hydroxyl chemistry. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2002jd002272] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- J. Lelieveld
- Max-Planck-Institute for Chemistry; Mainz Germany
| | - W. Peters
- Institute for Marine and Atmospheric Research; Utrecht Netherlands
| | - F. J. Dentener
- Joint Research Centre; Environment Institute; Ispra Italy
| | - M. C. Krol
- Institute for Marine and Atmospheric Research; Utrecht Netherlands
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Houweling S, Dentener F, Lelieveld J. Simulation of preindustrial atmospheric methane to constrain the global source strength of natural wetlands. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/2000jd900193] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Severinghaus JP, Brook EJ. Abrupt climate change at the end of the last glacial period inferred from trapped air in polar Ice. Science 1999; 286:930-4. [PMID: 10542141 DOI: 10.1126/science.286.5441.930] [Citation(s) in RCA: 423] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The last glacial period was terminated by an abrupt warming event in the North Atlantic approximately 15,000 years before the present, and warming events of similar age have been reported from low latitudes. Understanding the mechanism of this termination requires that the precise relative timing of abrupt climate warming in the tropics versus the North Atlantic be known. Nitrogen and argon isotopes in trapped air in Greenland ice show that the Greenland Summit warmed 9 +/- 3 degrees C over a period of several decades, beginning 14,672 years ago. Atmospheric methane concentrations rose abruptly over a approximately 50-year period and began their increase 20 to 30 years after the onset of the abrupt Greenland warming. These data suggest that tropical climate became warmer or wetter (or both) approximately 20 to 80 years after the onset of Greenland warming, supporting a North Atlantic rather than a tropical trigger for the climate event.
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Affiliation(s)
- JP Severinghaus
- Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92037, USA. Department of Geology, Washington State University, 14204 NE Salmon Creek Avenue, Vancouver, WA 98686, USA
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Triple-isotope composition of atmospheric oxygen as a tracer of biosphere productivity. Nature 1999. [DOI: 10.1038/22987] [Citation(s) in RCA: 230] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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21
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Kiselev A, Karol I. Modeling of the tropospheric carbon monoxide distribution in the northern temperate latitudinal belt. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s1465-9972(99)00006-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Wang Y, Jacob DJ. Anthropogenic forcing on tropospheric ozone and OH since preindustrial times. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/1998jd100004] [Citation(s) in RCA: 190] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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23
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Etheridge DM, Steele LP, Francey RJ, Langenfelds RL. Atmospheric methane between 1000 A.D. and present: Evidence of anthropogenic emissions and climatic variability. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98jd00923] [Citation(s) in RCA: 384] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Wang Y, Jacob DJ, Logan JA. Global simulation of tropospheric O3-NOx-hydrocarbon chemistry: 1. Model formulation. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98jd00158] [Citation(s) in RCA: 465] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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25
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Timing of abrupt climate change at the end of the Younger Dryas interval from thermally fractionated gases in polar ice. Nature 1998. [DOI: 10.1038/34346] [Citation(s) in RCA: 533] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Brook EJ, Sowers T, Orchardo J. Rapid Variations in Atmospheric Methane Concentration During the Past 110,000 Years. Science 1996; 273:1087-91. [PMID: 8688091 DOI: 10.1126/science.273.5278.1087] [Citation(s) in RCA: 271] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A methane record from the GISP2 ice core reveals that millennial-scale variations in atmospheric methane concentration characterized much of the past 110,00 years. As previously observed in a shorter record from central Greenland, abrupt concentration shifts of about 50 to 300 parts per billion by volume were coeval with most of the interstadial warming events (better known as Dansgaard-Oeschger events) recorded in the GISP2 ice core throughout the last glacial period. The magnitude of the rapid concentration shifts varied on a longer time scale in a manner consistent with variations in Northern Hemisphere summer insolation, which suggests that insolation may have modulated the effects of interstadial climate change on the terrestrial biosphere.
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Affiliation(s)
- EJ Brook
- E. J. Brook and J. Orchardo, Graduate School of Oceanography, University of Rhode Island, Narragansett, RI 02882, USA. T. Sowers, 447 Deike Building, Geosciences Department, Pennsylvania State University, University Park, PA 16802, USA
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