**Comparison of EPA's RGGS CALPUFF modeling and variants to WRAP BART modeling results** sjb 2011-03-26

All simulations used ENSR meteorology (WRAP AZ domain, CALMET 5.8, with upper air data), except the WRAP results per se. All simulations used visibility method 6, with annual average natural background concentrations. Impacts listed are 98th percentile delta deciviews (ddv). "avg" = average of 2001-2003 individual year results; "mult" = all three years' data considered together for 98th percentile

**Conclusions PM speciation change made little difference;**  **using WRAP CALPUFF puff parameters increased Grand Canyon impacts by 50%; using WRAP CALMET meteorology increased impacts by another 20-100% increase, including 60% at Grand Canyon.** 
**WRAP Comparison Simulations**

**CALMET CALPUFF** **POSTUTIL CALPOST** **emission**
**s Sequence of changes** 
5.8 5.8 1.56 5.6394 EPA(PM10 modeled as PMC, PMF, SO4, EC, SOA) 5.8 5.8 1.56 5.6394 WRAPSmall emission change ; total PM modeled as PMF 5.8 5.8 1.56 5.6394 WRAPSome puff parameters 5.8 5.8 1.56 6.131 WRAPCALPOST version 6.211 6.112 1.52 6.131 WRAPCALPUFF & POSTUTIL versions 6.211 6.112 < 1.5? 6.1? WRAPMeteorology, bigger computational grid, TimeZone=8

**c00 / rgset2 (used by EPA for proposal)** Absolute Differences Relative Differences **vs. prev.**vs. rgset2vs. WRAP **vs. prev.**vs. rgset2vs. WRAP
area 2001 2002 2003avg mult 2001 2001 brca 0.181 0.204 0.295 0.227 0.203 -0.109 -37.6% grca 0.725 0.589 0.508 0.607 0.585 -0.995 -57.8% jotr 0.663 0.583 0.446 0.564 0.508 -0.217 -24.7% syca 0.127 0.177 0.134 0.146 0.135 -0.063 -33.2% zion 0.307 0.382 0.601 0.430 0.390 -0.523 -63.0% WRAP per se **Name** versions of executables

c00 / rgset2 cwe / rgset2_wrapem WRAP0_cf5.8_ct5.6 WRAP0_cf5.8_ct6.1 WRAP0_cf6.1_ct6.1**Comparison of EPA's RGGS CALPUFF modeling and variants to WRAP BART modeling results** sjb 2011-03-26

**cwe / rgset2_wrapem; change from c00 rgset2** Absolute Differences Relative Differences **vs. prev.**vs. rgset2vs. WRAP **vs. prev.**vs. rgset2vs. WRAP 2001 2001 2001 2001 2001 2001 2001 brca 0.180 -0.001 -0.001 -0.110 -0.6% -0.6% -37.9% grca 0.699 -0.026 -0.026 -1.021 -3.6% -3.6% -59.4% jotr 0.653 -0.010 -0.010 -0.227 -1.5% -1.5% -25.8% syca 0.123 -0.004 -0.004 -0.067 -3.1% -3.1% -35.3% zion 0.304 -0.003 -0.003 -0.526 -1.0% -1.0% -63.4% Coarser PM speciation: Small decreases

**WRAP0_cf5.8_ct5.6; change from cwe** Absolute Differences Relative Differences **vs. prev.**vs. rgset2vs. WRAP **vs. prev.**vs. rgset2vs. WRAP 2001 2001 2001 2001 2001 2001 2001 brca 0.186 0.006 0.005 -0.104 3.3% 2.8% -35.9% grca 1.075 0.376 0.350 -0.645 53.8% 48.3% -37.5% jotr 0.717 0.064 0.054 -0.163 9.8% 8.1% -18.5% syca 0.121 -0.002 -0.006 -0.069 -1.6% -4.7% -36.3% zion 0.402 0.098 0.095 -0.428 32.2% 30.9% -51.6% **Change puff parameters: Increase at Grand Canyon big, Zion moderate, Bryce & Joshua Tree small , slight decrease at Sycamore Canyon**

**WRAP0_cf5.8_ct6.1; change from WRAP0_cf5.8_ct5.6** Absolute Differences Relative Differences **vs. prev.**vs. rgset2vs. WRAP **vs. prev.**vs. rgset2vs. WRAP 2001 2001 2001 2001 2001 2001 2001 brca 0.186 0.000 0.005 -0.104 0.0% 2.8% -35.9% grca 1.075 0.000 0.350 -0.645 0.0% 48.3% -37.5% jotr 0.717 0.000 0.054 -0.163 0.0% 8.1% -18.5% syca 0.121 0.000 -0.006 -0.069 0.0% -4.7% -36.3% zion 0.402 0.000 0.095 -0.428 0.0% 30.9% -51.6% Change CALPOST version from 5.6394 to 6.131: No effect.**Comparison of EPA's RGGS CALPUFF modeling and variants to WRAP BART modeling results** sjb 2011-03-26

**WRAP0_cf6.1_ct6.1; change from WRAP0_cf5.8_ct6.1** Absolute Differences Relative Differences **vs. prev.**vs. rgset2vs. WRAP **vs. prev.**vs. rgset2vs. WRAP 2001 2001 2001 2001 2001 2001 2001 brca 0.186 0.000 0.005 -0.104 0.0% 2.8% -35.9% grca 1.075 0.000 0.350 -0.645 0.0% 48.3% -37.5% jotr 0.717 0.000 0.054 -0.163 0.0% 8.1% -18.5% syca 0.121 0.000 -0.006 -0.069 0.0% -4.7% -36.3% zion 0.402 0.000 0.095 -0.428 0.0% 30.9% -51.6% Change CALPUFF version from 5.8 to 6.112: No effect (but results stated in terms of end of preceding day, rather than start of current day)

**WRAP report; change from WRAP0_cf6.1_ct6.1** Absolute Differences Relative Differences **vs. prev.**vs. rgset2 **vs. prev.**vs. rgset2 2001 2002 2003avg 2001 2001 2001 2001 brca 0.29 0.21 0.37 0.29 0.104 0.109 55.9% 60.2% grca 1.72 1.03 1.00 1.25 0.645 0.995 60.0% 137.2% jotr 0.88 0.56 0.55 0.67 0.163 0.217 22.7% 32.7% syca 0.19 0.17 0.14 0.17 0.069 0.063 57.0% 49.6% zion 0.83 0.46 0.74 0.68 0.428 0.523 106.5% 170.4% **Change meteorology ENSR 2008 to WRAP 2007: Big increase at most areas , moderate incr. at Joshua Tree**