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Visibility and Haze
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Visibility Report to Congress - November 2001

Visibility in Mandatory Federal Class I Areas, 1994-1998
A Report to Congress

  • Cover Page (pdf) (176.58 KB)
  • Table of Contents (pdf) (83.34 KB)
  • Front Pages (Abbreviations, Acronyms, Glossary of Terms) (pdf) (117.13 KB)
  • Executive Summary (pdf) (253.37 KB)
  • Chapter 1 - Introduction to Visibility Issues (pdf) (355.07 KB)
  • Chapter 2 - Visibility in Individual Mandatory Federal Class I Areas (pdf) (3.54 MB)
  • Chapter 3 - National and Regional Discussions of Visibility (pdf) (1.17 MB)
  • Chapter 4 - References (pdf) (75.92 KB)
  • Appendix A - List of 156 Mandatory Federal Class I Areas Where Visibility is an Important Value (pdf) (69.66 KB)
  • Appendix B - Explanation of Method for Creating Summary Data from Raw IMPROVE Data (pdf) (61.7 KB)
  • Appendix C - Methodology for Calculating Light Extinction from Monitored Aerosol Mass Data (pdf) (211.38 KB)
  • Appendix D - Theil Method to Determine Statistically Significant Trends (pdf) (85.58 KB)
  • Technical Report Data (pdf) (5.18 KB)
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Contact Us to ask a question, provide feedback, or report a problem.
Last updated on January 19, 2023
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