New CoHA Product Access Page & Representativeness Analysis 7 Feb 2007

New Query Tool on CoHA web In beta testing… Select CoHA results using this query page Select site or all sites within a state

Example Selecting New Mexico gives you all of the CoHA products for that state for all 9 class I areas

Representativeness Assessment Assessment of the representativeness of 2002 worst case days compared to a five year base period (2000 to 2004) Based on CoHA HYSPLIT runs with EDAS and FNL For each IMPROVE site in the WRAP region Generated two maps at each site: Difference between 2002 and the 5-year worst 20% residence time Ratio of 2002 over the 5-year worst 20% residence time

What Contributes to Variations? Differences in annual residence time during the worst case days may be due to: drought El Nino, La Nina year to year variations in wildfires intensity, number and locations local and regional high wind dust events Asian dust events (one significant one in 2002) stagnation events as represented by high sulfate, organics and nitrate

Meteorological Variations 2002 was a moderate El Niño year Summer of 2002 was hot and dry compared to climate Surface temperature anomaly map showing anomalies of around 1.5 degrees C through most of WRAP region

Variability in Smoke PMF Smoke Factor for 2002 Contribution of PMF smoke factor to PM2.5 in µg/m3

Fires in 2002

Variations in Dust Concentrations Comparison of dust (fine dust + coarse mass) on 2002 compared to 2001- 2003 mean Based on DRI’s Causes of Dust Analysis

Variations in # of Dust Days Comparison of the number of worst case dust days in 2002 compared to 2001- 2003 mean Based on DRI’s Causes of Dust Analysis

Click on this icon to access 2002 Representativeness maps

Example: Agua Tibia Difference map Ratio map

Interpretations Computing a difference map of 2002 RT versus 5-year RT gives positive numbers for higher than average frequencies from those areas and negative for lower than average frequencies Ratio of 2002 to 5-year RT gives "enhancement" factor when passing over those areas, but no information about frequency

Gila Wilderness Example Difference Ratio

THANKS!