1. Urbanized-MM5 urban-climate simulations of Houston-Galveston Bob Bornstein* R. Balmori and H. Taha Dept. of Meteor., San Jose State Univ. San Jose, CA USA for copy of ppt: *pblmodel@hotmail.com pblmodel@hotmail.com presented at 6 th ICUC Göteborg, Sweden 12-16 June 2006

2. OVERVIEW Introduction Introduction –MM5 –Urbanized uMM5 Houston uMM5 Urban Ozone-Study Houston uMM5 Urban Ozone-Study –GC/Synoptic influences –Gulf & Bay breezes –Urban-climate effects Current Current After tree-planting After tree-planting –Ozone-transport patterns Future Work Future Work

3. Urbanization Techniques Urbanize subsurface, surface, UCL, SBL, & PBL: Urbanize subsurface, surface, UCL, SBL, & PBL: momentum, thermo, & TKE Eqs From forest-canopy model (Yamada 1982) From forest-canopy model (Yamada 1982) Veg param replaced with urban (GIS/RS) terms Veg param replaced with urban (GIS/RS) terms –Brown and Williams (1998) –Masson (2000): urban-canyon energy-budget –Martilli et al. (2001): urban+PBL in TVM –Dupont et al. (2003): Martilli + EPA/MM5 (for Ching)  UPC –Taha et al. (2005): LU/LC + UPC  uMM5

4. From EPA uMM5: Mason + Martilli (by Dupont) Within Gayno-Seaman PBL/TKE scheme

5.  Advanced urbanization scheme from Masson Martilli et al. 3 new-terms in each prog. PBL eq. e.g., Momentum ↓ Building: vol & sfc area

6. uMM5 inputs as f (x, y)  land use (38 categories)  roughness elements  anthropogenic heat as f (z, t)  building heights  paved surface-fractions  building drag-force coefficients  building height-to-width, wall-to-plan, & impervious-area ratios  building frontal, building plan, & rooftop area-densities  ε, cρ, α, etc. of walls and roofs

7. UCP-inputs (1 km grid) Houston: Ching & Burian (2006) Building plan area fraction Wall-to-Plan area ratio Building frontal area index Height-to-Width ratio

8. max urban effect Brown & Williams: urbanized meso-met model TKE(z) h c =building top

9. uMM5 Houston Runs: 22-26 August 2000 Model configuration Model configuration –5 Domains: 108, 36, 12, 4, 1 km –(x,y) grids: 43x53, 55x55, 100x100, 136x151, 133x141 –  levels: 29 in Ds1-4; 49 in D5; lowest ½  = 7 m –2-way feedback in D1-4 –96 CPU  4.5 hr for a 24 hr simulation Physics options Physics options > Grell Cu in D1-2 > ETA or MRF PBL in Ds 1-4 > Grell Cu in D1-2 > ETA or MRF PBL in Ds 1-4 > Gayno-Seaman TKE PBL in D5 > Simple ice > Gayno-Seaman TKE PBL in D5 > Simple ice > Urbanization in D-5 > NOAH LSM > RRTM radiation > Urbanization in D-5 > NOAH LSM > RRTM radiation Inputs Inputs > NNRP Reanalysis + ADP obs > NNRP Reanalysis + ADP obs > Burian LIDAR building-data in D5 > Burian LIDAR building-data in D5 > Byun LU/LC modifications > Byun LU/LC modifications

10. Houston Galveston emissions: 2 nd most O 3 -polluted US city SHIP CHANNEL AREA Houston-Galveston refineries & chemical plants: along Galveston Bay ship-channel (Source: Byun 2003)

11. Episode-day Synoptics: 8/25, 12 UTC (08 DST) H H 700 hPa z = 30 m D z = 30 m Surface p = 4 hPa D p = 4 hPa 700 hPa & sfc GC H’s: at weakest (no gradient) over Texas  meso-scale forcings (sea-breeze & UHI-convergence) dominate

12. Concurrent NNRP fields at 700 hPa & sfc H NNRP-inputs to MM5 (as IC/BC) captured GC/synoptic location & strength of NWS-H (on previous slide)  MM5 can thus do well (Bornstein 2006) H D p= 2 hPa D z = 30 m

13. MM5: episode day, 3 PM > D–1: reproduced weak GC p-grad & V > D-2: new weak coastal-L > D-3: (well formed) L  along-shore V L D-1 D-2 D-3 L

14. Domain 4 (3 PM) : L off of Houston on high O 3 day (25 th ) LL  Episode day day

15. uMM5 Domain 5 sfc-winds at 3 PM: 4 successive days  Episode day: off-shore L  along-coast V  warm-inland  high O high O 3 C H

16. 25 Aug (episode day) 1500 UTC (same as last slide) Observed winds at different-scales: alongshore flow Tx2000 HGA HGA (gridded)

17. L H C > 02 UTC: UHI Con > O 3 : urban-L + weak left-over H H 17 UTC: Bay Breeze + Ship Channel max H L H 18 UTC: urban L (titration) O 3 Interval: 5 ppb (00-16 UTC) & 10 ppb (>16 UTC) H L 14 UTC 15 16 17 18 19 21 23 23 UTC Gulf Breeze & trajec- tory of O 3 max + Houston Heat-pump Note: early stagnation

18. Urban-effects on night-(non UHI, as wet rural soil) speeds (D-5): z 0  speed-decreases (m/s) over urban-centers - - - + + + + V Obs uMM5 + + ++ +

19. Daytime UHI (wet rural soil)  urban-induced convergence & acceleration Gridded Obs uMM5 C C C 08/24/00

20. Along–shore V came from Cold-Core L: D-3 MM5 vs Obs Temps MM5: produces coastal cold-core low 18 UTC, Cold-core L (only 1-ob) & Urban area (blue-dot clump) seems to retards cold-air penetration! C H H

21. D-5 uMM5-MM5 UHI at 8 PM on 21 Aug Upper L: MM5 UHI = 2.0 K Upper L: MM5 UHI = 2.0 K Upper R: uMM5 UHI = 3.5 K Upper R: uMM5 UHI = 3.5 K Lower L: uMM5-MM5 = Lower L: uMM5-MM5 = 1.5 K stronger UHI 1.5 K stronger UHI Blob is LU/LC error Blob is LU/LC error H + H C

22. 8/23 Day UHI: obs vs uMM5 (D-5): 2-m Temps H Obs: 1 PM uMM5: 3 PM Cold UHI C

23. Base-case veg (0.1s): urban-min of current tree -cover Modeled increase tree-cover ( 0.01s): urban reforestation rural deforestation

24. Run 14 (urban-reforestation) minus Run 13 (base case): 4 PM 2-m ∆T (K) > reforested urban-areas are cooler > surrounding deforested rural-areas are warmer C’er W’er

25. D UHI(t): Base-case minus Runs 15-18 D UHI(t): Base-case minus Runs 15-18 UHI = Temp in Urban-Box minus Temp in Rural-Box UHI = Temp in Urban-Box minus Temp in Rural-Box Runs 15-18: urban re-forestation scenarios Runs 15-18: urban re-forestation scenarios D UHI = Run-17 UHI minus Run-13 UHI  D UHI = Run-17 UHI minus Run-13 UHI  max effect, green line Reduced UHI  lower max-O 3 (not shown)  Reduced UHI  lower max-O 3 (not shown)  EPA emission-reduction credits  $ saved  Max-impact of –0.9 K of a 3.5 K Noon-UHI, of which 1.5 K was from uMM5 URBAN RURAL

26. Houston Summary NNRP captured GC forcing for MM5: weak High NNRP captured GC forcing for MM5: weak High uMM5 captured the thus strong observed meso effects uMM5 captured the thus strong observed meso effects –Weak offshore Low –Ship-Channel (large source area) stagnation –Sequential Bay and Gulf breezes –Urbanization LU/LC characteristics –Houston: UHI & heat-pump –Urban-V patterns UHI convergence/acceleration UHI convergence/acceleration Roughness deceleration Roughness deceleration –Ozone transport-processes Urban reforestation Urban reforestation –Decreased max-daytime UHI-values –Should thus also decrease max-O 3 values

27. FUTURE WORK (1) Current uMM5  reduced Houston-UHI  Current uMM5  reduced Houston-UHI  reduced: energy use, biogenics, photolosis  reduced (?) CAMx/CMAQ O 3  EPA emission-reduction credits Update uMM5 inputs Update uMM5 inputs –Deep-soil BC-temp to eliminate min-T bias –IC soil-moisture (post rain-storm) to eliminate max-T bias –Satellite SST as f(x,y,t) –Better sea-surface z eq. –Better sea-surface z 0 eq. –Dave Sailor Q via NSF project –Dave Sailor Q a via NSF project

28. FUTURE WORK (2) SJSU/NCAR (Fei Chen) uWRF DTRA proposal SJSU/NCAR (Fei Chen) uWRF DTRA proposal –uMM5 scheme –Zilitinkevich: diag SBL-eqs for very stable & unstable conditions –Freedman: prog k-ε PBL eqs –1-way link to: ER canyon-dispersion models Downscaled climate-change model-output  increased NYC (with Columbia/GISS) Downscaled climate-change model-output  increased NYC (with Columbia/GISS) > thermal-stress deaths (to NSF) > thunderstorms  urban floods (to NSF) > air pollution (to EPA) > air pollution (to EPA)

29. ACKNOWLEDGEMENTS D. Hitchock & P. Smith, State of TX D. Hitchock & P. Smith, State of TX D. Byun, U. of Houston D. Byun, U. of Houston J. Nielsen-Gammon, T&M U. J. Nielsen-Gammon, T&M U. J. Ching & S. Dupont, US EPA J. Ching & S. Dupont, US EPA S. Stetson, SWS Inc S. Stetson, SWS Inc S. Burian, U. of Utah S. Burian, U. of Utah D. Nowak, US Forest Service D. Nowak, US Forest Service Funding from: USAID, NSF, DHS, HARC Funding from: USAID, NSF, DHS, HARC

30. Houston and uMM5 References Balmori, R., 2006: Urbanized MM5 study of urban impacts on an August 2000 Houston O episode. MS Thesis, Dept. of Met., SJSU. Balmori, R., 2006: Urbanized MM5 study of urban impacts on an August 2000 Houston O 3 episode. MS Thesis, Dept. of Met., SJSU. Banta, R. M., et al., 2005: A bad air day in Houston. Bull. Amer. Meteor. Soc., 86, 657-669. Banta, R. M., et al., 2005: A bad air day in Houston. Bull. Amer. Meteor. Soc., 86, 657-669. Byun, D., et al., 2004: Modeling effects of land use/land cover modifications on the UHI and air quality in Houston, Texas. Tech. Note, University of Houston, 55 pp. Byun, D., et al., 2004: Modeling effects of land use/land cover modifications on the UHI and air quality in Houston, Texas. Tech. Note, University of Houston, 55 pp. Dupont, S., et al., 2003: Simulation of meteorological fields within and above urban and rural canopies with MM5. Tech. Rep., US EPA NOAA, ARL, NC, 67 pp. Dupont, S., et al., 2003: Simulation of meteorological fields within and above urban and rural canopies with MM5. Tech. Rep., US EPA NOAA, ARL, NC, 67 pp. Martilli, A., et al., 2002: An urban surface exchange parameterization for mesoscale models. Boundary-Layer Meterol., 104, 261-304. Martilli, A., et al., 2002: An urban surface exchange parameterization for mesoscale models. Boundary-Layer Meterol., 104, 261-304. Nielsen-Gammon, J. W., 2004: The surprising dynamics of the Houston urban sea breeze. Preprints, 84th AMS Conf, Seattle, WA. Nielsen-Gammon, J. W., 2004: The surprising dynamics of the Houston urban sea breeze. Preprints, 84th AMS Conf, Seattle, WA. Taha, H., et al., 2005: UHI alterations from urban-forest changes in Houston: uMM5 model of Aug 2000 O episode. SJSU Report to HARC. Taha, H., et al., 2005: UHI alterations from urban-forest changes in Houston: uMM5 model of Aug 2000 O 3 episode. SJSU Report to HARC.

31. The End Any Questions?