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2007), Phenomenological reconstructions of the solar signature in the NH surface temperature records since 1600
- J. Geophys. Res
"... Northern Hemisphere surface temperature records since 1600 ..."
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Cited by 47 (19 self)
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Northern Hemisphere surface temperature records since 1600
2009), Effects of anthropogenic land cover change on the carbon cycle of the last millennium, Global Biogeochem
- Cycles
"... of the last millennium ..."
Terrestrial carbon cycle dynamics under recent and future climate change
- Journal of Climate
, 2005
"... The behavior of the terrestrial carbon cycle under historical and future climate change is examined using the University of Victoria Earth System Climate Model, now coupled to a dynamic terrestrial vegetation and global carbon cycle model. When forced by historical emissions of CO 2 from fossil fuel ..."
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Cited by 24 (4 self)
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The behavior of the terrestrial carbon cycle under historical and future climate change is examined using the University of Victoria Earth System Climate Model, now coupled to a dynamic terrestrial vegetation and global carbon cycle model. When forced by historical emissions of CO 2 from fossil fuels and land-use change, the coupled climate–carbon cycle model accurately reproduces historical atmospheric CO 2 trends, as well as terrestrial and oceanic uptake for the past two decades. Under six twenty-first-century CO 2 emissions scenarios, both terrestrial and oceanic carbon sinks continue to increase, though terrestrial uptake slows in the latter half of the century. Climate–carbon cycle feedbacks are isolated by comparing a coupled model run with a run where climate and the carbon cycle are uncoupled. The modeled positive feedback between the carbon cycle and climate is found to be relatively small, resulting in an increase in simulated CO 2 of 60 ppmv at the year 2100. Including non-CO 2 greenhouse gas forcing and increasing the model’s climate sensitivity increase the effect of this feedback to 140 ppmv. The UVic model does not, however, simulate a switch from a terrestrial carbon sink to a source during the twenty-first century, as earlier studies have suggested. This can be explained by a lack of substantial reductions in simulated vegetation productivity due to climate changes. 1.
The early anthropogenic hypothesis: Challenges and responses
- Rev. Geophys
, 2007
"... anthropogenic intervention caused CH4 and CO2 increases that kept climate from cooling and that preindustrial pandemics caused CO2 decreases and a small cooling. Every aspect of this early anthropogenic hypothesis has been challenged: the timescale, the issue of stage 11 as a better analog, the abil ..."
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Cited by 20 (0 self)
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anthropogenic intervention caused CH4 and CO2 increases that kept climate from cooling and that preindustrial pandemics caused CO2 decreases and a small cooling. Every aspect of this early anthropogenic hypothesis has been challenged: the timescale, the issue of stage 11 as a better analog, the ability of human activities to account for the gas anomalies, and the impact of the pandemics. This review finds that the late Holocene gas trends are anomalous in all ice timescales; greenhouse gases decreased during the closest stage 11 insolation analog; disproportionate biomass burning and rice irrigation can explain the methane anomaly; and pandemics explain half of the CO2 decrease since 1000 years ago. Only 25 % of the CO2 anomaly can, however, be explained by carbon from early deforestation. The remainder must have come from climate system feedbacks, including a Holocene ocean that remained anomalously warm because of anthropogenic intervention.
What should protected area managers do in the face of climate change? The George Wright Forum
, 2005
"... Recent climate change. While rapid in terms of geological time scales, these changes were, well, geological in pace. Over the past 100 years, however, global average temperature has risen approximately 0.6°C, and the rate of warming has greatly acceler-a ted since the 1970s (Figure 2). T h i s chang ..."
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Cited by 17 (0 self)
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Recent climate change. While rapid in terms of geological time scales, these changes were, well, geological in pace. Over the past 100 years, however, global average temperature has risen approximately 0.6°C, and the rate of warming has greatly acceler-a ted since the 1970s (Figure 2). T h i s change is ascribed mainly to rapid and large releases of greenhouse gases from the burn-ing of fossil fuels for power generation and t ransportation (IPCC 2001a). It is eve n possible that we re it not for incre a s e d releases of CO2 and CH4 due to the burn-ing of forests to clear land for agriculture, starting around 8,000 years ago, and the invention of rice paddy cultivation about 6,000 ye a rs ago, the Earth would have a l re a dy ente red the next glacial inte r va l (Ruddiman 2003). Impacts of re cent climate change. There is ample evidence of the physical and ecological impacts of recent climate change. Walther et al. (2002) summarize many of these observed changes, such as increased
Abstract Science for Global Sustainability: Toward a New Paradigm
, 2005
"... This paper provides a context for the Dahlem Workshop on “Earth System Analysis for Sustainability.” The authors begin by characterizing the contemporary epoch of Earth history in which humanity has emerged as a major—and uniquely self-reflexive—geological force. They turn next to the extraordinary ..."
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Cited by 9 (0 self)
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This paper provides a context for the Dahlem Workshop on “Earth System Analysis for Sustainability.” The authors begin by characterizing the contemporary epoch of Earth history in which humanity has emerged as a major—and uniquely self-reflexive—geological force. They turn next to the extraordinary revolution in our understanding of the Earth system that is now underway, pointing out how it has built on and qualitatively extended the approaches that have served science and society so well since the first Copernican revolution. The authors then discuss the novel challenges posed by the urgent need to harness science and other forms of knowledge in promoting a worldwide sustainability transition that enhances human prosperity while protecting the Earth’s life-support systems and reducing hunger and poverty. Finally, the authors provide an overview of how the contributions to this Dahlem Workshop addressed the
F.: The early anthropogenic hypothesis a year later
- Climatic Change
, 2005
"... Ruddiman (2003) introduced a three-part hypothesis on early anthropogenic in-fluences on late Holocene climate. He proposed that humans reversed a natural decrease in atmospheric CO2 values 8000 years ago by starting to clear forests for farms, that they reversed a natural methane decrease after 500 ..."
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Cited by 5 (0 self)
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Ruddiman (2003) introduced a three-part hypothesis on early anthropogenic in-fluences on late Holocene climate. He proposed that humans reversed a natural decrease in atmospheric CO2 values 8000 years ago by starting to clear forests for farms, that they reversed a natural methane decrease after 5000 years ago mainly by
Ecology & the Accumulation of Capital: A Brief Environmental History of Neoliberalism
"... The developing tendencies of history constitute a higher reality than the empirical ‘facts ’ (Lukács, 1971: 181). “We have mixed our labour with the earth, our forces with its forces too deeply to be able to draw back and separate either out,” Raymond Williams first argued in 1971 (1980: 83). In an ..."
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Cited by 5 (1 self)
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The developing tendencies of history constitute a higher reality than the empirical ‘facts ’ (Lukács, 1971: 181). “We have mixed our labour with the earth, our forces with its forces too deeply to be able to draw back and separate either out,” Raymond Williams first argued in 1971 (1980: 83). In an extraordinary essay, Williams directs his critique towards those “singular abstractions ” – society and nature – that confuse and obscure the historical relations between humans and the rest of nature. But this is only part of what makes Williams ’ argument so extraordinary. While we may perceive (or fail to perceive) the “products ” of humanity’s “complex dealings with the physical world, ” Williams outlines an approach that would demolish the fictions inscribed in these singular abstractions, and deliver “not only a more sophisticated but a more radically honest accounting. ” This alternative accounting is one premised on relations rather than “products”: We ourselves are products: the pollution of industrial society is to be found not only in the water and in the air, but in the slums, the traffic jams, and not these only as physical objects 1
The Palaeoanthropocene – The beginnings of anthropogenic environmental change. Anthropocene Available at:
, 2014
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Soils as sources and sinks of greenhouse gases
"... intact peatlands and from rice agriculture; asN20 from unmanaged and managed soils; and as CO2 from land-use change. Methane emissions attributable to other wetlands add another 1.6-3.8 Gt CO2 equivalents. From a global standpoint, N20 from unmanaged soils and CH 4 from peatlands and other wetlands ..."
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intact peatlands and from rice agriculture; asN20 from unmanaged and managed soils; and as CO2 from land-use change. Methane emissions attributable to other wetlands add another 1.6-3.8 Gt CO2 equivalents. From a global standpoint, N20 from unmanaged soils and CH 4 from peatlands and other wetlands make soils naturally net greenhouse gas emitters. In addition, the storage of carbon in soils and the fluxes of CH 4 and N20 have been changed by anthropogenic effects towards emission rates 52 to 72 % above those under natural conditions before the dawn of intensive agriculture and land-use change. Land-use changes on mineral soils induced most of the recorded losses of soil organic matter (SOM), but there is evidence that proper agricultural management of soil resources is able to recover some of these losses and to maintain soil functions. However, the discrep-ancy between so-called 'sequestration potentials ' and the measures already adopted is amazingly large. Globally, only about 5 % of the cropped areas is managed according to practices uch as no tillage or organic farming. The contribution f soil loss by erosion, desertification a d sealing to global oxidative SOM losses is uncertain; however, in the case of soil erosion, it is considered to be a major factor in global SOM decline. Mitigation
