Joseph Aldy Provides Perspective on the new Intergovernmental Panel on Climate Change Report

April 7, 2014
By Jenny Li Fowler

The recent report by the Intergovernmental Panel on Climate Change, a United Nations group that periodically summarizes climate science, concluded that ice caps are melting, sea ice in the Arctic is collapsing, water supplies are coming under stress, and other unsettling outcomes if the world stays on its current course.
Joseph Aldy, assistant professor of public policy, helps put the panel’s findings in perspective.
Q:The new report makes several dire conclusions about the impacts of climate change. How do you assess the validity of these findings?
Aldy:The IPCC brings together a group of experts to review and report on the work of the world’s experts on climate change. As a result, the conclusions the IPCC has drawn on the impacts of climate change reflect what many experts have known, because these conclusions are based on papers already published in the top academic journals. If one focuses on evidence, as opposed to political rhetoric, there is no doubt that climate change is occurring, that climate change reflects in large part the contributions of anthropogenic emissions of greenhouse gases, and that climate change will have significant impacts on the lives and livelihoods of people around the world.
Q:The report cites a “domino effect” from climate change that could lead to violent conflicts over land, water and other resources. In what parts of the world is this most likely to occur?

Aldy:Those regions of the world that are already vulnerable to weather and climatic shocks as well as those with weaker infrastructure and institutions, are most likely to experience conflicts over resources. Wealthier nations have much more capacity and financial resources to adapt to a changing climate, but lower-income developing countries may lack the human and financial capital necessary to undertake even modest adaptation investments and strategies. As a result, climate change will likely stress these poor countries’ abilities to provide food and water to their populations.
Q:How will this report incentivize governments to act to confront the challenge of climate change?
Aldy:One important lesson from the international climate negotiations over the past 25 years is that countries do not take actions that are not consistent with their domestic interests. Enhancing public understanding of the risks posed by climate change may facilitate broader domestic support for more aggressive emission abatement and adaptation efforts. It is important that this information drive politically active citizens and voters, whose actions can then impact decision-makers in governments around the world.
Q:President Obama is seeking to impose new limits on the country’s greenhouse emissions. What opposition does he face in the Congress?
Aldy:The most environmentally effective and economically efficient way to address climate change in the United States would be through new, well-designed legislation that would employ market-based approaches to mitigate greenhouse gas emissions. President Obama attempted to work with Congress on such an approach during his first term. A sufficient number of Members of Congress opposed this approach that it stymied the legislative option.
Given the lack of progress with Congress, the President has tasked the Environmental Protection Agency (EPA) to develop greenhouse gas emission standards. The Supreme Court ruled in 2007 that the EPA has the authority under the Clean Air Act to regulate greenhouse gas emissions. Under this authority, the EPA has already regulated carbon dioxide emissions from cars, light trucks, and heavy-duty vehicles. The EPA will finalize a rule establishing a greenhouse gas emission standard on new power plants and propose a greenhouse gas emission standard on existing power plants this year. These actions all fall under existing statutory authority.
This leaves those in Congress who oppose these actions to address climate change with only two options. First, they could pass a new law to change the Clean Air Act. Second, they could challenge the final regulations through the Congressional Review Act, which provides Congress with the opportunity to disapprove of and effectively reject a regulation. Since these actions would require a supermajority in the House and the Senate to override an expected Presidential veto, they are not likely. As a result, political opposition by Members of Congress will likely take the form of statements, hearings, etc., not explicit actions that stop the President’s climate change policy agenda.

Joseph Aldy, assistant professor of public policy

Joseph Aldy, assistant professor of public policy

"One important lesson from the international climate negotiations over the past 25 years is that countries do not take actions that are not consistent with their domestic interests."


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