Lake breezes in the lower Great Lakes region during BAQS-Met 2007

1. Lake breezes in the lower Great Lakes region during BAQS-Met 2007 David Sills1, Jeff Brook2, Ilan Levy2, Paul Makar2, Junhua Zhang2, Peter Taylor3, Katherine Hayden2, and Lesley Elliott1 1Cloud Physics and Severe Weather Research Section, Environment Canada, Toronto, Canada 2Air Quality Research Division, Environment Canada, Toronto, Canada 3Department of Earth and Space Science and Engineering, York University, Toronto, Canada 2011 GLOM Workshop 21–23 March, Ithaca, NY

2. Like déjà vu all over again My lake breeze-related presentations at GLOMW: • 1997 – ELBOW 97 • 1999 – more ELBOW 97 • 2000 – lake breezes and tornadoes • 2002 – ELBOW 2001 • 2003 – more ELBOW 2001 • 2005 – lake breezes at RSD • 2010 – comparing GEM / RUC lake breeze forecasts Co-authored lake breeze-related presentations at GLOMW: • 2001 – ELBOW 2001 • 2004 – BAQS-Met preparations • 2008 – lake breezes / air quality case study What more could this guy possibly sayabout #%&@ lake breezes?!?

3. Busy beavers • Continuing analysis of the ELBOW 2001 data • New data and analysis from the BAQS-Met 2007 lake breeze / air quality study • Updated conceptual understanding of lake breezes and their impacts in the lower Great Lakes region

4. Why are lake breezes important? • Affect the climate of the region around the lake • Affect summer severe weather: • Lake air typically suppresses thunderstorms • The lake-breeze front provides a lifting mechanism for the initiation of thunderstorms, most often over land • Affect air quality: • 3-D transport of pollutants / precursors in lake-breeze circulations • Increased insolation for photochemistry (ozone) • Decreased mixing height reduces pollutant dispersion

5. Past lake breeze research • Great Lakes lake breeze studies • Biggs and Graves 1962, Estoque 1962, Moroz 1967, Lyons 1972, Estoque et al. 1976, Estoque 1981, Ryznar and Touma 1981, Comer and McKendry 1993, Sills 1998, Laird et al. 2001, etc. • Great Lakes lake breezes / svr wx studies • Shenfeld and Thompson 1962, Changnon 1966, Murphy 1991, Leduc et al. 1993, Clodman and Chisholm 1994, King 1996, King et al. 1996, King 1997, Sills 1998, King and Sills 1998, Sills and King 1998, King et al. 1999, Roebber and Eise 2001, King et al. 2003, etc. • Great Lakes lake breezes / air quality studies • Lyons 1972, Lyons and Cole 1973, Lyons and Olsson 1973, Lyons and Cole 1976, Mukammal et al. 1982, Lyons et al. 1995, Reid et al. 1996, Sills 1998, Hastie et al. 1999, Harris and Kotamarthi 2005, etc.

6. BAQS-Met 2007 • Border Air Quality and Meteorology Study • Focused on Detroit-Windsor and surrounding areas • Environment Canada, York University, University of Toronto, University of Western Ontario • June – August 2007, intensive 20 June – 10 July • Investigate the impacts of mesoscale boundary-layer phenomena, particularly lake-breeze circulations, on local air quality and the regional transport of pollutants

8. Lake breeze (front) detection

9. Lake breeze (front) detection

10. Lake breeze (front) detection Each has strengths and weaknesses, integrating data setsimproves lake-breeze front detection

11. Wind Direction Ozone PM2.5 Wind Speed Temperature Dew Point Lake breeze (front) detection 1 min data Merlin Station (~10 km N of Lake Erie)

12. Lake breeze stats For entire BAQS-Met 2007 period: • Much higher than Great Lakes studies in literature (13 - 45%)… • 100% of high ozone* days had active lake breezes • 86% of days with thunderstorms had active lake breezes • 100% of severe thunderstorm days had active lake breezes * 1-hr avg O3 >= 80 ppb at more than one station

13. Incredible lake breeze facts! During BAQS-Met study period: • Only one day in June / July without a lake breeze in study area • Three periods with lake breezes on all lakes occurring over 11 consecutive days or more (8 June–18 June, 20 June–10 July, 21 July–4 August) • Longest was 21 days (BAQS-Met IOP!) • The Lake Huron shore had 24 consecutive lake breeze days between 20 June and 13 July • That’s twice the highest number of consecutive lake breeze days previously reported (12 days on the Lake Michigan shore; Eichenlaub, 1979) • Greatest observed lake-breeze front penetration distance was over 200 km

14. ‘Classic’ Low Deformation (LD) Moderate-deformation (MD) High-deformation (HD)

15. ‘Classic’ Low Deformation (LD) Moderate Deformation (MD) High-deformation (HD)

16. ‘Classic’ Low Deformation (LD) Moderate Deformation (MD) High Deformation (HD)…

17. Lake breeze stats - intensive During the 21-day intensive observation period: • Lake breezes on each lake on each day of intensive • 9 high ozone days, 3 thunderstorm days, 2 severe thunderstorm days – all with lake breeze influences • Wide variety of synoptic regimes – wind speed light to moderate, direction S through NNE • 3 LD, 13 MD, and 5 HD lake-breeze circulations • 16 Twin Otter aircraft flights • Great data set! • Animations for each day athttp://tinyurl.com/SillsBAQS-MetAnimations

18. GEM-LAM 2.5 Runs sfc winds + 815 m vertical velocity • 58 hybrid-coordinate levels increasing monotonically with height from the Earth’s surface to 10 hPa • Initial and boundary conditions for these high-resolution runs from 15 km GEM-REG with same vertical coordinates as the high-resolution simulation • No convective parameterization scheme • Used to drive air chemistry model (AURAMS)

19. LD Case

21. MD Case

23. HD Case (Mildmay tornadoes)

25. Obs vs GEM penetration distancesat 1700 Local Time

26. Obs vs GEM penetration distancesat 1700 Local Time

27. Obs vs GEM penetration distancesat 1700 Local Time Maximum penetration distances (km): 215 245 185 160 100 125

28. 215 km LH Penetration

29. 23 June 2007 Wind direction Temperature Dew point Very sharpgradients Frontal widths ~200 m! 190000 UTC

30. Lift at lake-breeze fronts Updrafts at fronts up to 5 m s-1, but not quite how we thought… 2000 F r e e A t m o s p h e r e ENTRAINMENT ZONE CAPPING INVERSION Residual Layer /Return Flow LCL 1000 Height (m) Convective Mixed Layer LCL CAPPING INVERSION Inflow Layer TIBL 0 Land Lake Horizontal Distance

31. Lift at lake-breeze fronts Updrafts at fronts up to 5 m s-1, but not quite how we thought… 2000 F r e e A t m o s p h e r e ENTRAINMENT ZONE CAPPING INVERSION Residual Layer /Return Flow LCL 1000 Height (m) Convective Mixed Layer LCL CAPPING INVERSION Inflow Layer TIBL 0 Land Lake Horizontal Distance

32. 18 Jul 2007 Chatham area (E of LSC)

33. No severe weather reported!?

36. MLCAPE ~ 900 K/kg 0-6 km shear = 39 knots

37. BAQS-Met publications to date • Special issue of Atmospheric Chemistry and Physics • Brook, J. R, P. A. Makar, D. M. L. Sills, K. L. Hayden, and R. McLaren, 2011: The 2007 Border Air Quality and Meteorology Study: exploring the nature of air quality over southern Ontario. Submitted to Atmos. Chem. Phys. Discuss. • Hayden, K.L., D. M. L. Sills, J. R. Brook, S.-M. Li, P. Makar,M. Z. Markovic, P. Liu, K. G. Anlauf, J. M. O’Brien, Q. Lin, and R. McLaren, 2011: The impact of lake breezes on trace gases and particles during BAQS-Met 2007. Submitted to Atmos. Chem. Phys. Discuss. • Sills, D. M. L., J. R. Brook, I. Levy, P. A. Makar, J. Zhang, and P. A. Taylor, 2011: Lake breezes in the southern Great Lakes region and their influence during BAQS-Met 2007. Atmos. Chem. Phys. Discuss., 11, 3579-3626. • Levy, I., P. A. Makar, D. Sills, J. Zhang, K. L. Hayden, C. Mihele, J. Narayan, M. D. Moran, S. Sjostedt, and J. Brook: Unraveling the complex local-scale flows influencing ozone patterns in the southern Great Lakes of North America, Atmos. Chem. Phys., 10, 10895-10915. • Makar, P. A., J. Zhang, W. Gong, C. Stroud, D. Sills, K. L. Hayden, J. Brook, I. Levy, C. Mihele, M. D. Moran, D. W. Tarasick, and H. He, 2010: Mass tracking for chemical analysis: the causes of ozone formation in southern Ontario during BAQS-Met 2007. Atmos. Chem. Phys., 10, 11151-11173. • Many more related to various aspects of atmospheric chemistry

38. ELBOW 2001 Results

39. Convective Initiation • Work by PhD candidate Lisa Alexander at YorkU • Radar cells reaching 40 dBz were identified, and their distance to the nearest boundary measured • Boundary and cell type/direction/speed, plus other parameters also recorded

40. Convective Initiation • Cell initiation clearly occurs more frequently closer to boundaries • Found that moving boundaries were by far the best initiators of storms (78%) • Also, lake-breeze fronts often generated the first storm cells, but subsequent gust fronts initiated the most storm cells (55%)

42. Facing NE 1351 LT 18 Jul 05

43. Huron Erie

44. Building Cu No Cu No Cu Cloud base (LCL) Huron Erie

45. Acknowledgements • Norbert Driedger, Emma Hung, Brian Greaves for their work on the mesoanalysis database and products • Jake Urbanek, Bradley Drummond, Tomasz Stapf, Steven Brady, Tatiana Bukhman and Julie Narayan for contributions to data collection and quality control • Katherine Hayden and Craig Stroud for assistance with data analysis • Patrick King for many years of collaborative work on southern Ontario lake breezes

46. Future Work • Lots of analysis left to do for both ELBOW 2001 and BAQS-Met 2007 • Focus on vertical velocity and parcel trajectories at lake-breeze fronts using aircraft data and GEM model output • Also lake-breeze front interactions • Will allow better understanding of factors affecting thunderstorm initiation and svr wx • Look for yet another lake breeze talk soon!