Air pollution - Climate change impacts

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

View this study at:

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

guus.velders@rivm.nl

Title

Emission scenarios for a global hydrogen economy and the consequences for global air pollution

Reference

Global Environmental Change
Volume 21, Issue 3, August 2011, Pages 983-994
Symposium on Social Theory and the Environment in the New World (dis)Order

Author(s)

Bas van Ruijven,, Jean-Francois Lamarque, Detlef P. van Vuuren, Tom Kram, Hans Eerens

Study type

Peer Review Journal

Abstract

Hydrogen is named as possible energy carrier for future energy systems. However, the impact of large-scale hydrogen use on the atmosphere is uncertain. Application of hydrogen in clean fuel cells reduces emissions of air pollutants, but emissions from hydrogen production and leakages of molecular hydrogen could influence atmospheric chemistry. This paper combines a global energy system model and a global atmospheric model to explore the range of impacts of hydrogen on atmospheric chemistry. We found that emissions of molecular hydrogen may range from 0.2 up to 10% (or 25-167 Tg hydrogen/yr) for a global hydrogen energy system. The lower end of this range would in fact be equal to current emissions from fossil fuel combustion. Hydrogen energy use leads to a clear decrease in emissions of carbon monoxide, nitrogen oxides and sulphur dioxide, but large-scale hydrogen production from coal may lead to net increase in emissions of nitrous oxide and volatile organic compound. Compared to a reference scenario, this would lead to positive impacts on surface concentrations of carbon monoxide, nitrogen oxides and ozone. However, if hydrogen leakage would not be minimised it leads to an increase in methane lifetimes and a decrease in stratospheric ozone concentrations.

Policy theme(s)

Air pollution >> Source of emissions >> Transport emissions
Air pollution >> Impact of emissions >> Climate change impacts
Environmental technologies >> Climate change mitigation >> Low carbon technologies
Environmental technologies >> Pollution control >> Low polluting technologies

Keywords:

Hydrogen energy; Atmospheric chemistry; Molecular hydrogen emissions; Stratospheric ozone; Air polluting emissions

Entry Source:

Selected for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://www.sciencedirect.com/science/article/pii/S0959378011000409
There is a fee to view this study in full

Contact the study author at:

bas.vanruijven@pbl.nl