The U.S. National Climate Assessment (NCA; Melillo et al., 2014) identified a number of ways in which climate change is affecting or is likely to affect, people, infrastructure, natural resources, and ecosystems. Those impacts in turn have the potential for important current and future consequences for human health. Research on these impacts is active, with strong evidence to support some aspects and research still in progress for others. Therefore, there is a need to assess our understanding of how the impacts of climate change on the environment can create stressors that can affect human health in a number of dimensions both now and in the future.
In response to this need, the U.S. Global Change Research Program (USGCRP) has initiated an interagency Assessment on the Impacts of Climate Change on Human Health in the United States. The Assessment is intended to inform public health authorities, other planning and policy entities, and the general public. It extends the work begun under the 2008 Synthesis and Assessment Product 4.6 (USGCRP, 2008) Analyses of the Effects of Global Change on Human Health and Welfare and Human Systems and the third NCA released in 2014.
The National Academies of Sciences, Engineering, and Medicine have been asked to conduct an independent review of the Draft Assessment and to address the following questions (see Appendix B):
- Does the report meet its stated goals?
- Is the report responsive to the nation’s needs for information on the health impacts of climate change and their potential implications?
- Does the report accurately reflect the scientific literature? Are there any critical content areas missing from the report?
- Are the approaches to quantitative modeling reasonable and adequately supported by existing literature?
- Are the findings documented in a consistent, transparent, and credible way?
- Are the report’s key messages and graphics clear and appropriate? Specifically, do they reflect supporting evidence, include an assessment of likelihood, and communicate effectively?
- Are the research needs identified in the report appropriate?
A Committee was convened to conduct the review, and this document contains an evaluation presented in answers to the Statement of Task questions, individual chapter reviews, and detailed comments compiled in Appendix A. The Committee was impressed by the tremendous amount of work undertaken to develop such an extensive scientific assessment and suggests ways to improve the document to ensure that the Assessment is responsive to the nation’s needs for information on the possible health impacts of climate change and that the key messages reach a broad audience.
The Committee offers a number of overarching suggestions (in response to its Statement
- Clearly outline the selection process and criteria used to choose the health outcomes and literature discussed within the chapters;
- Clarify the criteria used to judge likelihood and confidence statements and consider disaggregating confidence determinations in key findings to better reflect the diversity of the evidence;
- Reorganize some key findings to improve clarity and to highlight the evidence of health impacts of climate change first and foremost;
- Enhance the discussions of vulnerability from the earliest stages of the Assessment and review the discussion of vulnerability throughout the chapters for consistency;
- Consistently discuss adaptive behavior in the context of each chapter and describe, to the extent that there is literature available, potential adaptive behaviors and interventions that could moderate the health impacts;
- Provide methods for all featured modeling results, including uncertainties and information on accessing the underlying data;
- Consider reordering the chapters to minimize overlap and to enhance opportunities for linkages between related issues;
- Enhance the overarching graphic (Figure ES-1 and similar figures) to effectively portray the key concepts and ensure uniformity of the message; and
- Consistently identify the most important research needs within each chapter.
The Committee appreciates the opportunity to comment on this important work and notes that, with attention to the suggested enhancements, this Assessment will clearly play a significant role in continued efforts to examine and explore the impacts of climate change on human health.