Understanding the lake breeze and other drivers of ozone in Southeast Wisconsin Kohler Andrae State Park, Sheboygan, WI Angela Dickens, Ph.D. – with Mike Majewski, Bob Lopez & David Bizot Policy Analyst LADCO and Wisconsin Department of Natural Resources

Lake Michigan Shoreline: WI’s worst ozone problems 2 Draft ozone design values: data have been QA’ed but are not yet been reviewed by EPA

Lake Michigan Shoreline: WI’s worst ozone problems 3 Nonattainment for 2008 standard Draft ozone design values: data have been QA’ed but are not yet been reviewed by EPA

Lake Michigan Shoreline: WI’s worst ozone problems 4 Nonattainment for 2008 standard Draft ozone design values: data have been QA’ed but are not yet been reviewed by EPA

5 Lakeshore Ozone in Wisconsin Chicago Milwaukee

76 ppb 71 ppb 66 ppb 61 ppb Emissions and ozone are way down, but… LADCO model projections for 2018 From Alex Cohan, LADCO 6

One problem: Models don’t do a good job reproducing the lake breeze Can’t accurately model ozone along the lakeshore Needed for attainment demonstrations, etc. Major needs for Wisconsin: Understand the lake breeze better Improve modeling of the lake breeze 7

8 Use of paired lakeshore-inland monitors DRAFT Design Values Data have been QA’ed but have not been reviewed by EPA Operated miles inland Operated 2013 & miles inland

9 Use of paired lakeshore-inland monitors DRAFT Design Values Data have been QA’ed but have not been reviewed by EPA Operated miles inland Operated 2013 & miles inland 1-hour ozone concentrations

Wind conditions leading to high ozone Kenosha lakeshore site ( ) 10

Wind conditions leading to high ozone Kenosha lakeshore site ( ) 11

Inland Wind conditions leading to high ozone Lakeshore-inland comparison (2014 only) Lakeshore 12

Inland Wind conditions leading to high ozone Lakeshore-inland comparison (2014 only) Lakeshore Different wind directions lead to high ozone 13

Comparison of lakeshore and inland monitor concentrations One-hour ozone concentrations for 2013 & 2014 (June-August only) Kenosha 14

Comparison of lakeshore and inland monitor concentrations One-hour ozone concentrations for 2013 & 2014 (June-August only) Kenosha 15

Comparison of lakeshore and inland monitor concentrations One-hour ozone concentrations for 2013 & 2014 (June-August only) Kenosha 16

17 Comparison of lakeshore and inland monitor concentrations One-hour ozone concentrations for 2014 (June-August only) Kenosha Lakeshore exceeds standard Inland exceeds standard >80

18 Comparison of lakeshore and inland monitor concentrations One-hour ozone concentrations for 2014 (June-August only) Only one inland 8-hour average exceeded the standard Kenosha Lakeshore exceeds standard Inland exceeds standard >80

19 Comparison of lakeshore and inland monitor concentrations One-hour ozone concentrations for 2014 (June-August only) Only one inland 8-hour average exceeded the standard Kenosha Lakeshore exceeds standard Inland exceeds standard >80 Lakeshore-inland difference (ppb)

20 Comparison of lakeshore and inland monitor concentrations One-hour ozone concentrations for 2014 (June-August only) Only one inland 8-hour average exceeded the standard 7-12 ppb (10-17%) Larger differences in Sheboygan (11-17 ppb) Kenosha Lakeshore exceeds standard Inland exceeds standard >80 Lakeshore-inland difference (ppb)

Differences in ozone concentrations Kenosha lakeshore-inland sites (2013 & 2014) (winds shown are for the lakeshore monitor) 21

Differences in ozone concentrations Kenosha lakeshore-inland sites (2013 & 2014) (winds shown are for the lakeshore monitor) 22

Conclusions: Ozone drops off sharply within a few km of the shoreline Ozone concentrations and concentration differences are largest with southerly winds Exact direction varies depending on geography Very narrow range of wind direction for a site Different wind conditions lead to high ozone inland versus on the lakeshore 23

Other Efforts: 1) Fine-scale modeling of the Lake Michigan lake breeze AQAST Re-Analysis Tiger Team project: Brad Pierce & Scott Spak 2) Model validation from the LADCO Aircraft Project Theresa Foley, Army Research Laboratory 3) Ground-based and satellite analysis of ozone precursors in WI Tracey Holloway & students 4)Comparison and origins of ozone trends in WI and Chicago Ping Jing (Loyola U.) and David Streets 5) New field campaign??? 24

Thank you! 25

Effects of the lake breeze on ozone concentrations 2014 data have been QA’ed but are not yet been reviewed by EPA

Effects of the lake breeze on ozone concentrations pre/post-lake breeze Lake breeze Average of events 2014 data have been QA’ed but are not yet been reviewed by EPA

Effects of the lake breeze on ozone concentrations pre/post-lake breeze Lake breeze Average of events 2014 data have been QA’ed but are not yet been reviewed by EPA

Effects of the lake breeze on ozone concentrations 2014 data have been QA’ed but are not yet been reviewed by EPA

Effects of the lake breeze on ozone concentrations Pre/post lake breeze Lake breeze 2014 data have been QA’ed but are not yet been reviewed by EPA