This report surveys existing law for legal issues that have arisen, or may arise in the future, on account of climate change and government responses thereto. I. Two of these doctrines, standing and political question, have posed daunting barriers for plaintiffs in climate change cases. How does he show, say, that a drought that destroyed his crops was caused by climate change—indeed, by climate change to which the defendant's greenhouse gas (GHG) emissions contributed? Mitigation—Reducing GHG Emissions

Proactive responses to climate change are usually grouped under one of two headings: mitigation and adaptation. In 2012, the D.C. In 2014, the Supreme Court handed down Utility Air Regulatory Group v. EPA (UARG), answering no to the above question—that is, EPA's regulation of vehicle GHG emissions does not give EPA unqualified authority to apply PSD new source permitting and Title V operating permits to stationary source GHG emissions. Nor did UARG directly touch on the validity of EPA's current use of CAA section 111 in its effort to control GHG emissions from new and existing fossil-fuel-fired power plants. 3. The legal issues raised by climate change under these "little NEPAs" are beyond the scope of this report. Among the emerging legal issues associated with CCS technology are (1) who owns and controls the underground pore space where the CO 2 would be "sequestered" under many of the CCS facility concepts proposed, in particular is pore space part of the surface estate or mineral rights under traditional property law principles; (2) which federal and state agencies would permit and regulate CO 2 pipelines transporting the gas from the point of generation to the sequestration site under the existing framework for pipeline regulation; and (3) concerns over liability exposure that may hinder development of CCS technology. DCC issues have been raised in a variety of climate-change-related contexts. Liability After American Electric Power Co., Inc. v. Connecticut

In American Electric Power Co., Inc. v. Connecticut , the Supreme Court read the CAA to bar federal judges from imposing their own limits on GHG emissions from fossil-fuel-fired power plants, separate from those imposed by EPA under that act. Some issues in the vast universe of insurance-coverage litigation seem to be especially relevant to climate change. There, the Court held that GHG emissions are "air pollutants" under the Clean Air Act, raising the possibility that this ruling will be used to enlarge policy coverage to bring in damage traceable to GHG emissions. Research reveals only one climate-change-related international law action filed against the United States. Climate Change-Induced Water Shortages

		A. These decisions resolved claims of Fifth Amendment takings of water rights and claims of government breach of water-supply contracts based on cutbacks in the amount of water delivered from federal water projects—as demanded by the Endangered Species Act and the Central Valley Improvement Act. But, it would appear, not otherwise. V. Sea Level Rise and Extreme Precipitation

		A. Effect of Sea Level Rise on the Beachfront Owner's Property Line

Sea level rise generally causes the boundary between land and water to move landward. E. Failure to Take Preventive Measures

The scientific consensus that climate change will lead to further sea level rise raises the issue whether governments can be held liable for failing to act to avert the harmful impacts of such rise. Beach Issues

			1. As a result, questions as to liability for harm to neighboring tracts may be raised more often. The Supreme Court, too, has turned its attention recently to beach renourishment projects. Arguably, however, the question remains open. The aim of such disinvestment would be to hold down repair and restoration costs as the result of floods and sea level rise, and to discourage new development in such areas or promote removal of existing development. Responding To and Rebuilding After Natural Disasters

		A. Responding

Legal questions inevitably arise as to whether public and private actions taken in an emergency, climate-change-related or otherwise, are subject to the same legal requirements as when there is no emergency.
This report surveys existing law for legal issues that have arisen, or may arise in the future, on account of climate change and government responses thereto.
At the threshold of many climate-change-related lawsuits are two barriers—whether the plaintiff has standing to sue and whether the claim being made presents a political question. Both barriers have forced courts to apply amorphous standards in a new and complex context.
Efforts to mitigate climate change—i.e., reduce greenhouse gas (GHG) emissions—have spawned a host of legal issues. The Supreme Court resolved a big one in 2007: the Clean Air Act (CAA), it said, authorizes EPA to regulate GHG emissions. Most of EPA's subsequent efforts to carry out that authority have been sustained by the D.C. Circuit. In 2014, however, the Supreme Court held that EPA's regulation of GHG emissions from motor vehicles does not categorically bring GHG emissions from power plants and factories under the permitting sections of the Act. EPA's alternative track for regulating GHG emissions from such "stationary sources," standards of performance for new and existing sources, also raises issues. Still other mitigation issues are (1) the role of the Endangered Species Act in addressing climate change; (2) how climate change must be considered under the National Environmental Policy Act; (3) questions raised by carbon capture and sequestration; and (4) constitutional constraints on state actions to control GHG emissions.
Liability for harms allegedly caused by climate change has raised another crop of legal issues. The Supreme Court has held that the CAA bars federal judges from imposing their own limits on GHG emissions from power plants, suggesting that common law remedies will play little role in addressing climate change. Questions of insurance policy coverage are also likely to be litigated. Finally, the applicability of international law principles to climate change has yet to be resolved.
Water shortages thought to be induced by climate change likely will lead to litigation over the nature of water rights. Shortages have already prompted several lawsuits over whether cutbacks in water delivered from federal projects effect Fifth Amendment takings or breaches of contract.
Sea level rise and extreme precipitation linked to climate change raise questions as to (1) the effect of sea level rise on the beachfront owner's property line; (2) whether public beach access easements migrate with the landward movement of beaches; (3) design and operation of federal levees; and (4) government failure to take preventive measures against climate change harms.
Other adaptation responses to climate change raising legal issues, often property-rights related, are beach armoring (seawalls, bulkheads, etc.), beach renourishment, and "managed retreat" measures. Retreat measures seek to move existing development away from areas likely to be affected by floods and sea level rise, and to discourage new development there.
Natural disasters to which climate change contributes may prompt questions as to whether response actions taken in an emergency are subject to relaxed requirements and, similarly, as to the rebuilding of structures destroyed by such disasters just as they were before.
Finally, immigration and refugee law appear not to cover persons forced to relocate because of climate change impacts such as drought or sea level rise.