While negotiations continue for a United Nations Framework Convention on Climate Change (UNFCCC) by December 2015 to take effect in 2020, a parallel effort to achieve fast climate mitigation is needed under the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) to slow current impacts and reduce risks of passing tipping points that trigger self-amplifying feedback mechanisms that accelerate warming. Fast reductions of short-lived climate pollutants (SLCPs), including black carbon (BC), methane (CH4), tropospheric ozone (TO3), and hydrofluorocarbons (HFCs), can cut the rate of climate change in half by mid-century and by two thirds in the Arctic. The Montreal Protocol can be used to quickly phase down production and consumption of high global warming potential (GWP) HFCs, which can avoid 0.1 °C of warming by 2050, and 0.5 °C by 2100, while catalyzing improvements in appliance energy efficiency, which will provide further climate change mitigation by reducing energy use and carbon dioxide (CO2) emissions, particularly in fast-growing economies like India and China. The simultaneous global deployment of existing technologies can reduce emissions of BC, CH4, and TO3by enough to avoid an additional 0.5 °C of warming by 2050, while providing immediate benefits for human health, agriculture, and sustainable development. Fast action to reduce the four SLCPs will reduce the risk of setting off irreversible feedback mechanisms and provide urgent optimism and momentum for a successful UN climate treaty in 2015.
This special issue on Ozone Layer Protection and Climate Change reflects the leadership of the Association of Environmental Studies and Sciences (AESS) in drawing interdisciplinary attention to important environmental issues. The authors are scientists, diplomats, regulatory authorities, environmental activists, and scholars who are intimately involved in actions that protect the stratospheric ozone layer and climate. This issue provides new information and insightful analytic summaries of critical issues in the protection of the atmospheric environment and is also an urgent appeal to professors and students to place atmospheric protection prominently in thinking, research, teaching, and professional activities related to “sustainable development.” The authors describe and document the bold steps taken by individual and institutional leaders involved in the Montreal Protocol to thwart catastrophic ozone layer destruction, which incidentally, albeit on a sound scientific basis, addressed climate change. Because of strong leadership, effective networking, and concepts such the “precautionary principle” and “start and strengthen,” the Montreal Protocol is considered to be the most successful global environmental treaty. For example, thanks to innovative approaches adopted by both industry and government, the Montreal Protocol has already replaced about 85 % of ozone-depleting greenhouse gases with low global warming potential alternatives and increased product energy efficiency. But hardwork is needed to overcome the important challenges that remain, such as the phasedown of the 15 % of alternatives that are high global warming potential hydrofluorocarbons. Scientists, government officials, scholars, and business people must push for higher standards to achieve the combined goals of reducing both ozone-depleting substances and greenhouse gases.
This assessment report aims to give a concise and accessible picture of the current availability of alternatives to high-global warming potential (GWP) hydrofluorocarbons (HFCs) in their main uses with the elaboration of their efficiency, cost-effectiveness, safety, environmental impacts, and technical performance, as well as their applicability at high ambient temperatures, with the goal of better informing decision-makers about the future of HFCs in a fast-evolving market and regulatory context.
This research paper draws on the discussions at a workshop held at Chatham House in April 2014, outlines the main issues around the question of how best to craft a fair and effective global response to the growth in HFC use. A number of key issues are central to the debate: the principle of equity between developed and developing countries; the availability of alternatives to HFCs; the need for financial support for developing countries; the legal relationship between the climate and ozone regimes; and, underlying all these, the need for political will to resolve these challenges.
Highlights the importance of national enforcement against illegal trade in ensuring reductions in the emission of chemicals that damage the ozone layer and the climate system.
There is growing international interest in mitigating climate change during the early part of this century by reducing emissions of short-lived climate pollutants (SLCPs), in addition to reducing emissions of CO2. The SLCPs include methane (CH4), black carbon aerosols (BC), tropospheric ozone (O3) and hydrofluorocarbons (HFCs). Recent studies have estimated that by mitigating emissions of CH4, BC, and O using available technologies, about 0.5 to 0.6◦C warming can be avoided by mid-21st century. Here we show that avoiding production and use of high-GWP (global warming potential) HFCs by using technologically feasible low-GWP substitutes to meet the increasing global demand can avoid as much as another 0.5◦C warming by the end of the century. This combined mitigation of SLCPs would cut the cumulative warming since 2005 by 50% at 2050 and by 60% at 2100 from the CO2-only mitigation scenarios, significantly reducing the rate of warming and lowering the probability of exceeding the 2◦C warming threshold during this century.
Stratospheric ozone, global warming, and the principle of unintended consequences—An ongoing science and policy success story.
This paper explores the business case for Indian AC companies to phase down HFCs and move to a future based on climate-friendly refrigerants and energy-efficient equipment designs.
Issue of Our Planet, the magazine of the United Nations Environment Programme.
