ACS Position Statement

Global Climate Change

ACS Statement on Global Climate Change

Summary

The ACS statement on global climate change reviews the science and recommends action on global climate issues.

ACS Position

Careful and comprehensive scientific assessments have clearly demonstrated that the Earth’s climate system is changing rapidly in response to growing atmospheric burdens of greenhouse gases and absorbing aerosol particles (IPCC, 2007). There is very little room for doubt that observed climate trends are due to human activities. The threats are serious and action is urgently needed to mitigate the risks of climate change.

The reality of global warming, its current serious and potentially disastrous impacts on Earth system properties, and the key role emissions from human activities play in driving these phenomena have been recognized by earlier versions of this ACS policy statement (ACS, 2004), by other major scientific societies, including the American Geophysical Union (AGU, 2003), the American Meteorological Society (AMS, 2007) and the American Association for the Advancement of Science (AAAS, 2007), and by the U. S. National Academies and ten other leading national academies of science (NA, 2005). This statement reviews key global climate change impacts and recommends actions required to mitigate or adapt to currently anticipated consequences.

Climate Change Impacts

The effects of projected unmitigated climate change on key Earth system components, ecological systems and human society over the next fifty years will be profound and, quite possibly, irreversible (IPCC, 2007). Higher surface temperatures will severely impact many land-based life forms, damaging vulnerable ecosystems and endangering key plant and animal species. Sea level is rising and the ocean is acidifying; the first threatens coastal habitations and ecosystems, the second will have profound effects on marine ecosystems. Snowfall and snowmelt patterns are changing and rainfall patterns may also be unstable, threatening fresh water supplies in vulnerable regions. Increases in severe weather events are very likely, with increasing damage due to floods, drought, and heat waves. We are, in effect, in the midst of a vast experiment with the Earth’s climate—with uncertain, but likely quite unpleasant, outcomes.

The costs of unchecked climate change in economic loss, human misery, and loss of ecosystem services are likely to be enormous. The United Nations Environment Programme estimated that climate change could cost world gross domestic product from $150 to $300 billion annually unless strong efforts are made by developed and developing nations to curb greenhouse gas emissions (UNEP, 2002). More recently, the Stern Review suggested that: "the overall costs and risks of climate change will be equivalent to losing at least 5% of global GDP [ca. $2 trillion] each year, now and forever" (Stern, 2007). Additional costs due to climate driven increases of refugees, illness, malnutrition, and conflicts over water, energy and food resources could easily dwarf the more easily estimated GDP losses. The costs of lost ecosystem services are difficult to compute, but may ultimately threaten the planet's capacity to sustain the current, much less the projected, population density (Daily et al, 2000).

Recommendations

1. Earth Systems Science

Successfully addressing the challenges of global climate change requires enhanced understanding of Earth system dynamics. Climate change is a very complex phenomenon involving the coupled physical, chemical and biological processes affecting the atmosphere, land surfaces and the oceans. The U.S. has been a leader in Earth system and climate change research, but funding for these activities has dropped dramatically over the past five years, slowing progress in vital areas of atmospheric chemistry, dynamics and radiation transport, cloud and aerosol chemistry and physics, ocean biogeochemistry and dynamics, glacial, ice cap and sea ice dynamics, hydrology, ecology, soil microbiology, multi-scale Earth system modeling and other key disciplines. The ability to quantify trends in climate parameters and resulting impacts on geological and ecological systems will require the enhancement and maintenance of sophisticated Earth observation satellites as well comprehensive in situ atmospheric, oceanic and ecological sensor systems.

Recommendation 1 - Re-invigorate and fully fund a comprehensive U.S. research program to better predict the impacts of climate change on regional, national and global scales and to allow the systematic analyses needed to effectively design and evaluate mitigation and adaptation strategies. Cooperation and collaboration with other nations on both an aggressive Earth systems research agenda and the necessary Earth observing systems should be emphasized.

2. Greenhouse Gas Emission Reduction

Progress to reduce U.S. and global greenhouse gas emissions to mitigate the scale and impact of accelerating climate change must start now using current technological capabilities. Opportunities to reduce CO2 emissions include enhanced fuel economy for on-road and off road vehicles, better insulated and more efficiently heated and cooled buildings, more efficient lighting, and more convenient and available mass transit.

Opportunities also exist to reduce CO2 emissions from fossil fuel combustion by substituting more sustainable biomass based fuels and by adopting non-combustion energy sources based on solar thermal, solar photovoltaic, wind, or tidal power. Successful deployment of enhanced energy conservation and fossil fuel substitution technologies will be expedited by increased research and development funding and shifts in government subsidies and incentives away from fossil fuel producers and users and to energy conservation efforts and more sustainable energy sources. Coal-fueled and nuclear electrical power generation systems may also be part of CO2 reduction strategies if effective and economic means to sequester CO2 emissions from coal combustion or advanced coal processing are developed for the former and if fuel diversion, spent fuel disposal, and power plant security issues are resolved for the latter.

Successful efforts to reduce petroleum and natural gas consumption through conservation or sustainable-fuel substitution will not only reduce net CO2 emissions, but also reduce reliance on fuel sources that are increasingly insecure for both economic and geopolitical reasons. Reduction in reliance on combustion driven energy systems will also contribute to both better air quality and reduced warming.

Many opportunities exist to reduce non-CO2 greenhouse emissions, including biogenic CH4 from landfills, agriculture and other land use practices and biogenic N2O from agricultural and non-agricultural fertilizer use, air pollutant deposition and waste disposal. Geological CH4 emissions associated with natural gas, petroleum and coal production, refining and distribution can also be reduced. Key knowledge needed to design, evaluate and implement better controls for theses non-CO2 greenhouse gases is likely to come from the enhanced Earth systems research called for in Recommendation 1. Reducing CH4 emissions also reduces secondary O3 and CO2 production and reducing N2O emissions reduces stratospheric ozone depletion.

It is certain that there will be no single solution to climate change challenges. Individual technologies may make more sense in particular situations or locales (e.g., solar or wind power). Others may merit national implementation (fuel efficiency standards). With adequate R&D funding, we may also be able to develop additional novel technologies and processes to mitigate climate change. For example, success in green chemistry and nanotechnology may dramatically reduce energy and materials use in the future. Several U.S. states and major municipalities have already set significant greenhouse reduction goals and implemented steps to meet them. The federal government needs to catch up with these forward-looking regions.

Enhanced research in the fields of energy efficiency and conservation, alternative and renewable energy sources, climate change adaptation, pollution prevention, and carbon sequestration also serves other important national goals, including economic prosperity, a high quality of life, and environmental protection. Developing and deploying these technologies will likely reduce energy costs, increase productivity, improve the nation’s energy independence, improve air and water quality, and reduce environmental hazards, in addition to reducing greenhouse gas emissions. These benefits are also sought by other nations opening up the potential of new export markets that could improve our nation’s trade balance.

Recommendation 2a – The U.S. should immediately adopt nationwide goals for rapid and deep reductions in CO2 and other greenhouse gas emissions and develop effective economic drivers to achieve these goals. Options such as emission cap and trade regimes, carbon taxes, or emissions taxes need to be devised, tested and implemented on a national basis. The U.S. should work closely with all major greenhouse gas emitter nations to secure their commitment to similar greenhouse gas emission reductions.

Recommendation 2b – The U.S. should significantly raise its public and private sector investments in technologies to mitigate climate change through economically viable energy conservation, biomass fuel substitution for fossil fuels, carbon sequestration and non-fossil fuel based energy sources. Key actions include

• Federal government revaluation of subsidies and incentives to allow advanced energy technologies to operate on an even playing field with the current, heavily subsidized energy sources.
• Enhanced federal R&D funding to develop both innovative energy sources with low net greenhouse gas emission and energy-efficient technologies and processes for the industrial, agricultural and transportation sectors.
• Business and industry should be encouraged to use private sector funding for development of enhanced low-emission, energy technologies and energy-efficient processes. Additional venture funding must be provided to commercialize new energy-efficient technologies. The growing international demand for advanced, sustainable energy and energy-efficient process technologies in both developed and developing countries represents a major market that U.S. based companies should make every effort to serve, reaping economic benefits for themselves and environmental benefits for everyone.
• Comprehensive evaluation of the life cycle environmental, health, safety, economic and social impacts of new technologies and processes before and during their implementation to ensure they help solve climate change issues without creating unanticipated societal and environmental problems.

3. Adaptation to Global Change

The current levels of long-lived atmospheric greenhouse gases and the levels of increased CO2 and heat absorbed by the world’s oceans ensures that the climate will continue to warm for decades, even if greenhouse gas and absorbing particle emissions are scaled back to more sustainable levels (IPCC, 2007). Thus, our nation and the world must adapt to inevitable changes in water supplies, agricultural productivity, severe weather patterns, sea-level rise and ecosystem viabilities. In order to devise and implement effective adaptation strategies we need to know more and to better communicate what we know to all levels of human society.

The enhanced research and development activities called for in Recommendation 1 will help us better predict the circumstances to which we must adapt. Additional research will be needed to understand how to enable society to survive and thrive under new climate conditions. The public will need to recognize and understand the challenges that need to be faced and to summon the social and political will to identify, evaluate and implement appropriate responses. Public media and educational institutions at all levels will need to be able to explain current and anticipated global change effects and potential response strategies.

Recommendation 3a – Collaboration at every level of government and with other nations should be encouraged to assess current global climate change impacts at regional, national and global scales and to share ways to successfully cope with climate change effects.

Recommendation 3b – The federal government should fund research on methods of adapting to climate change-induced conditions affecting infrastructure, agriculture, and the basic habitability of severely affected areas.

Recommendation 3c – Printed, video and web-based curricular materials examining global climate change and Earth system science, natural and societal impacts of global climate change, and ways individuals and organizations can adopt to reduce greenhouse gas emissions and adaptation options available to regions, states and municipalities should be developed and utilized at all educational levels, from elementary school through college. Media materials addressing these topics should also be developed and posted on continuously updated web sites that are widely advertised. Annual reports on global change issues should be prepared for the Congress and the Nation to stimulate and support informed dialog about how to best deal with climate change.

References

AAAS, 2007, AAAS Board Statement on Climate Change, American Association for the Advancement of Science, http://www.aaas.org/news/press_room/climate_change/mtg_200702/aaas_climate_statement.pdf

AGU, 2003, Human Impacts on Climate, American Geophysical Union, http://www.agu.org/outreach/science_policy/positions/climate_change2008.shtml

AMS, 2007, Climate Change, American Meteorological Society, http://www.ametsoc.org/POLICY/2007climatechange.html

Daily, G.C., et al., 2000, The Value of Nature and the Nature of Value, Science 289, 395-396.

IPCC, 2007, Intergovernmental Panel on Climate Change, http://www.ipcc.ch/

NA, 2005, Joint science academies’ statement: Global response to climate change, http://www.nationalacademies.org/onpi/06072005.pdf

Stern, N., 2007, The Economics of Climate Change, Cambridge University Press.

UNEP, 2002, Climate Change & the Financial Services Industry, United Nations Environment Programme, July 2002.