Climate change and energy - Air pollution and climate change

Title

Preserving Montreal Protocol Climate Benefits by Limiting HFCs

Reference

Science, 2012; 335 (6071): 922
DOI: 10.1126/science.1216414

Author(s)

G. J. M. Velders, A. R. Ravishankara, M. K. Miller, M. J. Molina, J. Alcamo, J. S. Daniel, D. W. Fahey, S. A. Montzka, S. Reimann

Study type

Peer Review Journal     

Abstract

The Montreal Protocol is perhaps the most successful international environmental treaty, responsible for global phaseout of the consumption and production of ozone-depleting substances (ODSs), e.g., chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs). Hydrofluorocarbons (HFCs), which do not destroy stratospheric ozone, were considered long-term substitutes for ODSs and are not controlled by the Montreal Protocol. Because most HFCs are potent greenhouse gases (GHGs), they are included in the Kyoto Protocol. But climate benefits provided by this protocol are limited as they apply only to developed countries and over a short time (2008–2012). As we describe below, with no impending global controls on HFCs, inclusion of HFCs under the Montreal Protocol offers a path, starting in the short term, to preserve the climate benefits already achieved by this protocol.

Policy theme(s)

Air pollution >> Impact of emissions >> Climate change impacts
Air pollution >> Impact of emissions >> Ozone layer impacts
Climate change and energy >> Greenhouse gas emissions >> Air pollution and climate change

Keywords

Entry Source:

Selected for Science for Environment Policy News Alert

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http://www.sciencemag.org/content/335/6071/922.summary
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Contact the study author at:

guus.velders@rivm.nl

Title

Earth's energy imbalance and implications

Reference

Atmospheric Chemistry and Physics, 11, 13421-13449, 2011
Part EU Funded
(Open Access)

Author(s)

J. Hansen, M. Sato, P. Kharecha, and K. von Schuckmann

Study type

Peer Review Journal    

Abstract

Abstract. Improving observations of ocean heat content show that Earth is absorbing more energy from the Sun than it is radiating to space as heat, even during the recent solar minimum. The inferred planetary energy imbalance, 0.58 ± 0.15 W m−2 during the 6-yr period 2005–2010, confirms the dominant role of the human-made greenhouse effect in driving global climate change. Observed surface temperature change and ocean heat gain together constrain the net climate forcing and ocean mixing rates. We conclude that most climate models mix heat too efficiently into the deep ocean and as a result underestimate the negative forcing by human-made aerosols. Aerosol climate forcing today is inferred to be −1.6 ± 0.3 W m−2, implying substantial aerosol indirect climate forcing via cloud changes. Continued failure to quantify the specific origins of this large forcing is untenable, as knowledge of changing aerosol effects is needed to understand future climate change. We conclude that recent slowdown of ocean heat uptake was caused by a delayed rebound effect from Mount Pinatubo aerosols and a deep prolonged solar minimum. Observed sea level rise during the Argo float era is readily accounted for by ice melt and ocean thermal expansion, but the ascendency of ice melt leads us to anticipate acceleration of the rate of sea level rise this decade.

Policy theme(s)

Climate change and energy >> Greenhouse gas emissions >> Air pollution and climate change

Keywords

Entry Source:

Selected for Science for Environment Policy News Alert

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http://www.atmos-chem-phys.net/11/13421/2011/acp-11-13421-2011.html
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Contact the study author at:

james.e.hansen@nasa.gov

Title

Simultaneously Mitigating Near-Term Climate Change and Improving Human Health and Food Security

Reference

Science 13 January 2012:
Vol. 335 no. 6065 pp. 183-189
DOI: 10.1126/science.1210026

Author(s)

Drew Shindell , Johan C. I. Kuylenstierna, Elisabetta Vignati, et al

Study type

Peer Review Journal    

Abstract

Tropospheric ozone and black carbon (BC) contribute to both degraded air quality and global warming. We considered ~400 emission control measures to reduce these pollutants by using current technology and experience. We identified 14 measures targeting methane and BC emissions that reduce projected global mean warming ~0.5°C by 2050. This strategy avoids 0.7 to 4.7 million annual premature deaths from outdoor air pollution and increases annual crop yields by 30 to 135 million metric tons due to ozone reductions in 2030 and beyond. Benefits of methane emissions reductions are valued at $700 to $5000 per metric ton, which is well above typical marginal abatement costs (less than $250). The selected controls target different sources and influence climate on shorter time scales than those of carbon dioxide–reduction measures. Implementing both substantially reduces the risks of crossing the 2°C threshold.

Policy theme(s)

Agriculture >> Agricultural management >> Food security
Air pollution >> Impact of emissions >> Health impacts
Air pollution >> Managing emissions >> Reduction measures
Climate change and energy >> Greenhouse gas emissions >> Air pollution and climate change

Keywords

Entry Source:

Selected for Science for Environment Policy News Alert

View this study at:

http://www.sciencemag.org/content/335/6065/183.abstract?sid=f40702ab-13ca-4dc4-8b1a-c1b0414daebe

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drew.t.shindell@nasa.gov

Title

Cost-effective control of air quality and greenhouse gases in Europe: Modeling and policy applications

Reference

Environmental Modelling and Software
Volume 26, Issue 12, December 2011, Pages 1489–1501
EU Funded

Author(s)

Study type

Peer Review Journal   

Abstract

Environmental policies in Europe have successfully eliminated the most visible and immediate harmful effects of air pollution in the last decades. However, there is ample and robust scientific evidence that even at present rates Europe's emissions to the atmosphere pose a significant threat to human health, ecosystems and the global climate, though in a less visible and immediate way. As many of the 'low hanging fruits' have been harvested by now, further action will place higher demands on economic resources, especially at a time when resources are strained by an economic crisis. In addition, interactions and interdependencies of the various measures could even lead to counter-productive outcomes of strategies if they are ignored.
Integrated assessment models, such as the GAINS (Greenhouse gas – Air pollution Interactions and Synergies) model, have been developed to identify portfolios of measures that improve air quality and reduce greenhouse gas emissions at least cost. Such models bring together scientific knowledge and quality-controlled data on future socio-economic driving forces of emissions, on the technical and economic features of the available emission control options, on the chemical transformation and dispersion of pollutants in the atmosphere, and the resulting impacts on human health and the environment. The GAINS model and its predecessor have been used to inform the key negotiations on air pollution control agreements in Europe during the last two decades.

This paper describes the methodological approach of the GAINS model and its components. It presents a recent policy analysis that explores the likely future development of emissions and air quality in Europe in the absence of further policy measures, and assesses the potential and costs for further environmental improvements. To inform the forthcoming negotiations on the revision of the Gothenburg Protocol of the Convention on Long-range Transboundary Air Pollution, the paper discusses the implications of alternative formulations of environmental policy targets on a cost-effective allocation of further mitigation measures.

Policy theme(s)

Air pollution >> Managing emissions >> Reduction measures
Climate change and energy >> Greenhouse gas emissions >> Air pollution and climate change

Keywords

Air pollution; Integrated assessment; Cost-effectiveness; GAINS model;
Convention on Long-range transboundary air pollution; Science–policy interface;
Decision support

Entry Source:

Shortlisted for Science for Environment Policy News Alert

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http://www.sciencedirect.com/science/article/pii/S1364815211001733
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Contact the study author at:

amann@iiasa.ac.at

Title

The climate penalty for clean fossil fuel combustion

Reference

Atmospheric Chemistry and Physics, 11, 12917-12924, 2011

Author(s)

W. Junkermann, B. Vogel, and M. A. Sutton

Study type

Peer Review Journal   

Abstract

To cope with the world's growing demand for energy, a large number of coal-fired power plants are currently in operation or under construction. To prevent environmental damage from acidic sulphur and particulate emissions, many such installations are equipped with flue gas cleaning technology that reduces the emitted amounts of sulphur dioxide (SO2) and nitrogen dioxide (NO2). However, the consequences of this technology for aerosol emissions, and in particular the regional scale impact on cloud microphysics, have not been studied until now. We performed airborne investigations to measure aerosol size distributions in the air masses downwind of coal-fired power installations. We show how the current generation of clean technology reduces the emission of sulphur and fine particulate matter, but leads to an unanticipated increase in the direct emission of ultrafine particles (1–10 nm median diameter) which are highly effective precursors of cloud condensation nuclei (CCN). Our analysis shows how these additional ultrafine particles probably modify cloud microphysics, as well as precipitation intensity and distribution on a regional scale downwind of emission sources. Effectively, the number of small water droplets might be increased, thus reducing the water available for large droplets and rain formation. The possible corresponding changes in the precipitation budget with a shift from more frequent steady rain to occasionally more vigorous rain events, or even a significant regional reduction of annual precipitation, introduce an unanticipated risk for regional climate and agricultural production, especially in semi-arid climate zones.

Policy theme(s)

Air pollution >> Source of emissions >> Industrial emissions
Climate change and energy >> Greenhouse gas emissions >> Air pollution and climate change

Keywords

Entry Source:

Selected for Science for Environment Policy News Alert

View this study at:

http://www.atmos-chem-phys.net/11/12917/2011/acp-11-12917-2011.html
There study is free to view 

Contact the study author at:

Wolfgang.junkermann@kit.edu