Project Period: June 2003- May 2008 Reports: 2005, 2008

1. Project Outline:Technical Support to EPA and RPOsEstimation of Natural Visibility Conditions over the US Project Period: June 2003- May 2008 Reports: 2005, 2008

2. The Haze Rules require States to establish and update Baseline, Natural and Current Visibility Conditions • Baseline conditions represent visibility at the time the regional haze program is established • Natural conditions represent the visibility conditions that would be experienced in the absence of human-caused impairment. • Current condition is the most recent multiyear average, to be revised for each SIP revision. It includes showing progress from the last revision and from the baseline period. • All three visibility parameters are to be derived from multiyear averaging of the best and worst 20% days

3. EPA Haze Rule on Natural Conditions • Reaching the natural visibility conditions is the goal of the EPA visibility program. • Estimating the natural and current conditions establishes how ‘‘close’’ a Class I area is to the goal, i.e. the magnitude of the human-induced ‘exceedance’ over the natural. • The default annual natural visibility is 11-2 deciview for the East, 8 dv for the West. • The regional natural visibility is to be derived from sulfate, nitrate, organic carbon, elemental carbon, and crustal material estimates using IMPROVE methodology. • EPA along with States, tribes, and FLMs to develop and refine the technical guidance on estimating natural conditions (e.g. natural fire and dust) - hence this project?? • States, in turn, will work with the FLMs, tribes and EPA in estimating their natural conditions using these guidelines at each Class I area in the time frame (2003–2005??)

4. Project Goal and Objective The goal of the project is to provide technical support to EPA & RPOs on: Estimation of Natural Visibility Conditions over the US Tasks and Approach: • Conceptual Evaluation of Natural PM and Visibility Conditions • Establish Virtual Workgroup with representatives from EPA, RPOs, scientific community • Quantitative Estimation of Recent Regional Natural Contribution Statistics • Conduct Data Analysis for estimating natural contributions (1995+, surf. and satellite obs) • Real-Time Estimation of Natural Aerosols and Visibility • Implement a Web-based Tool for routine real-time estimation of natural aerosols/visibility

5. Task 1: Conceptual Evaluation of Natural PM and Visibility Conditions • Establishing the main natural source types, e.g. • Windblown dust (local and distant) • Biomass smoke (forest, grass and other uncontrolled fires, local and distant) • Biogenic emissions (trees, marshes, oceans) • Sea salt • Physico-chemical properties of natural aerosols • Size distribution • Chemical composition • Optical properties • Evaluate suitable metrics for statistically describing natural conditions • Relevant aerosol components (e.g. SO4, NO3, OC, EC, Dust) • Spatial scales and resolution of natural events/conditions • Temporal scales and resolution of natural events/conditions

6. July Task 2: Quantitative Estimation of Regional Natural Contributions Approach: • Study each natural aerosol type in detail (dust, smoke, biogenic, sea salt) • Use ALL available aerosol observations (surface and satellite) and model results • Establish source strength/variability and spatio-temporal pattern at relevant scales (e.g.natural aerosol statistics) Example Natural Aerosol Analyses: Fine Dust SeaWiFS satellite image of Sahara dust approaching the continent (July 24,1998). In July, in the Southeast, Sahara dust contributes 4-8 mg.m3, about 2-4 times the local fine dust. For more detail see: Local and Global Dust Over N. America

7. Example Natural Aerosol Analyses: Biomass Smoke Nov 15, 1999 PM2.5 conc., smoke pattern and SeaWiFS image of plumes originating from Kentucky, Nov 15, 1999. Smoke Plumes Smoke Plumes Regional Smoke? Oct 5, 1998 Oct 5, 1998 Satellite data show numerous small fires in the Southeast but the nature of fires is not known. Prescribed burning? Wild fires? For more detail see: Carbonaceous Aerosol and Smoke over the Eastern US

8. Task 3. Real-Time Estimation of Natural Aerosols and Visibility • Rationale • The dominant natural aerosol sources are from windblown dust and biomass smoke. • Dust and smoke events can be monitored real-time by numerous surface and satellite sensors. • Both are ‘episodic’, i.e. short-term extreme concentrations that require AQ management actions. Real-time Aerosol Watch System (RAW) Real-Time Virtual PM Monitoring Dashboard.A web-page for one-stop access to views of current PM/Visibility monitoring data (aerosol, weather) and model output for nowcasting and forecasting. Virtual Workgroup Website.An interactive website which facilitates the active participation of diverse members in the interpretation, discussion, summary and assessment of the aerosol events. Air Quality Managers Console.Delivers a packaged PM data and summary reports prepared by the Virtual workgroups.Helps PM managers make decisions during major aerosol events. The development and implementation of RAW is already being supported at CAPITA by grants from NSF, NOAA, EPA/EMAP, NASA(pending). Incremental funding from this project would support estimating ‘Natural PM/Visibility Contributions’ during such events.

9. Illustration of RAW: Quebec Smoke, July 6, 2002 Right. SeaWiFS satellite and METAR surface haze shown near-real time in the Voyager distributed data browser Below. SeaWiFS, METAR and TOMS Absorbing Aerosol Index superimposed Satellite data are fetched from NASA GSFC; surface data from NWS/CAPITA servers

10. Schedule: Phase I: 2003 – 2005 2003 Conceptual evaluation of natural conditions 2003-5 Analyze natural events 2004-5 Regional natural aerosol statistics 2005 – Interim report Phase II: 2005 – 2008 2006 Re-evaluation of natural condition definitions 2006-8 Analyze natural events including model results 2007-8 Revised regional natural aerosol statistics 2008 – Final report