The Grand Canyon's iconic vistas are increasingly obscured by a persistent haze, prompting an urgent scientific investigation into its causes and effects. This report from the National Research Council details the findings of a comprehensive study aimed at understanding the atmospheric conditions contributing to this phenomenon. It examines the complex interplay of natural and anthropogenic factors, including emissions from regional sources and meteorological patterns, that lead to reduced visibility and potential ecological impacts within the park.

This report is recognized as a foundational scientific assessment of air quality issues within a major national park. It provides a detailed, data-driven analysis that has informed subsequent research and policy discussions regarding the preservation of natural visibility. The study's methodology and findings are cited in numerous academic papers and environmental impact assessments related to air pollution in protected areas.