Haze in the Grand Canyon -- Copyright -- Preface -- Contents -- Executive Summary -- BACKGROUND -- THE NATIONAL RESEARCH COUNCIL STUDY -- QUALITATIVE ASSESSMENT -- QUANTITATIVE ASSESSMENT -- ESTIMATES OF THE RANGE OF POSSIBLE IMPACTS FROM NGS -- THE COMMITTEE'S CONCLUSIONS IN PERSPECTIVE -- Haze in the Grand Canyon -- Haze in the Grand Canyon: An Evaluation of the Winter Haze Intensive Tracer Experiment -- BACKGROUND -- THE NRC COMMITTEE STUDY -- The Committee, Its Charge, and Its Approach -- The Committee's Specific Interpretation of Its Charge -- EVALUATION OF WHITEX -- Whitex Overview -- WHITEX SOURCE-ATTRIBUTION MODELS -- CRITICAL ASPECTS OF WHITEX TECHNIQUES AND DESIGN -- Qualitative Assessment -- Meteorological Evidence -- Photographic Evidence -- Chemical and Physical Evidence -- Quantitative Assessment -- LIMITATIONS OF THE WHITEX STUDY -- Weaknesses in the Data Base -- Uncertainties about Tracer Data -- Absence of Measurements within the Grand Canyon -- Inadequacy of Background Measurements -- Departures from Statistical Assumptions -- Formulation of Statistical Models -- Simplifications in the DMB Model -- Potential Covariance of NGS and Other Source Contributions -- Estimates of the Range of Possible Impacts of NGS Emissions at Hopi Point -- Minimum Conversion of SO2 to -- Maximum Conversion of SO2 to -- THE COMMITTEE'S CONCLUSIONS IN PERSPECTIVE -- CONCLUSIONS -- References -- Appendices -- Appendix 1: Nature of the Visibility Problem -- Contents -- Chapter 1 Introduction -- 1.1 Overview -- 1.2 Background -- 1.3 Study Plan -- 1.4 Interrelationships Between Aerosol, Optical and Visibility Apportionment -- 1.5 Measurement Program -- 1.6 Report Outline -- References -- Chapter 9 Conclusions -- 9.1 Introduction -- 9.2 Climatology of the Area -- 9.3 Light Extinction Budget -- 9.4 Attribution of Regional Sulfur and Visibility Impairment.

9.4.1 Emissions Analysis -- 9.4.2 Trajectory and Streakline Analysis -- 9.4.3 Spatial and Temporal Trends in Ambient Concentrations -- 9.4.4 Deterministic Wind Field Modeling -- 9.4.5 Tracer Mass Balance Regression (TMBR) Analysis -- 9.4.6 Differential Mass Balance (DMB) Analysis -- 9.4.7 Attribution of Visibility -- 9.4.8 Synthesis -- 3.2 CD4 Tracer Injection -- 3.3 Sample Collection -- Chemical Mass Balance With Unique Tracer -- Appendix 6B: Tracer Mass Balance Model Regression (TMBR) Model and Tracer Mass Balance (TMB) Model -- OVERVIEW -- MODEL EQUATIONS -- MODEL CALCULATIONS AND UNCERTAINTIES -- Model Assumptions -- Potential Deviations From Assumptions -- Effect of Nonconstant Regression Coefficients In The TMB Model -- MODEL INPUTS -- MODEL OUTPUTS -- Appendix 3: CD4 As An Air-Mass Tracer -- Appendix 4: Commission On Physical Sciences, Mathematics, And Resources -- STAFF.