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Impacts from urban & rural surface modifications on meteorology and air quality in Houston: preliminary results Haider Taha haider@altostratus.com Altostratus Inc. 940 Toulouse Way, Martinez, CA 94553 (925) 228-1573 Robert Bornstein San Jose State University pblmodel@hotmail.com Rochelle Balmori San Jose State University balmori@met.sjsu.edu For GUM Workshop, JULY 2004
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OUTLINE uMM5 CONFIGURATION uMM5 CONFIGURATION SYNOPTIC SUMMARY: 700 MB & SFC SYNOPTIC SUMMARY: 700 MB & SFC DOMAIN 1: MM5 SYNOPTIC WINDS VS NWS DOMAIN 1: MM5 SYNOPTIC WINDS VS NWS MM5 WINDS (MESO CONVENTION) MM5 WINDS (MESO CONVENTION) FULL BARB = 1 M/S FULL BARB = 1 M/S FLAG = 5 M/S FLAG = 5 M/S DOMAINS 2-4: MM5 WINDs DOMAINS 2-4: MM5 WINDs DOMAIN 5: uMM5 TEMPs DOMAIN 5: uMM5 TEMPs CONCLUSION CONCLUSION
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Model: EPA uMM5 (Dupont, Burian, et al.) Study: Aug-Sept Houston (Texas ’00) 0 3 episode Improve uMM5 input and physics Evaluate: uMM5 vs. MM5 performance Evaluate uMM5 sensitivity to LU/LC changes Work in progress:
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Urbanization Techniques Urbanize surface, SBL, & PBL momentum, Urbanize surface, SBL, & PBL momentum, thermo, & TKE Eqs Allows prediction within UCL Allows prediction within UCL From vegetation canopy-model of Yamada (1982) From vegetation canopy-model of Yamada (1982) Veg parameters replaced with urban (GIS/RS) terms Veg parameters replaced with urban (GIS/RS) terms Brown and Williams 1998 Brown and Williams 1998 Masson 2000 Masson 2000 Sievers 2001 Sievers 2001 Martilli et al. 2001 (in TVM) Martilli et al. 2001 (in TVM) Dupont et al. 2003 (in MM5) Dupont et al. 2003 (in MM5) LLNL 2004 LLNL 2004
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From Masson (2000)
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5-domain configuration, D0-5 is “urbanized” Resolution: 108, 36, 12, 4, 1 km Grid dimensions (excluding surface): 43×53×28, 55×55×28, 100×100×28, 136×151×28, 133×141×48.
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MM5 input + as f (x, y) in D-05: land use (38 categories) roughness elements anthropogenic heat as f (t) vegetation and building heights paved surface fractions drag-force coefficients for buildings & vegy building height-to-width, wall-to-plan, & impervious-area ratios building frontal, building plan, & and rooftop area-densities vegetation top- and area-densities root zone and sub-soil layers characterization vegetation-canopy characterization, stomatal resistance ε, cρ, α, etc. of walls and roofs
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Base-case vegetation cover (urban min)
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Modeled increases in vegetation cover (urban max)
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NWS SYNOPTICS
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1200 UTC (0700 DST) 24 AUG ‘00 700 mb 700 mb Pre-episode AM Pre-episode AM SE flow NE of Houston SE flow NE of Houston
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1200 UTC (0500 DST) 25 AUG ‘00 700 mb 700 mb Episode AM Episode AM Opposing NE flow NE of Houston Opposing NE flow NE of Houston Will cause con with sfc SB V Will cause con with sfc SB V
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1200 UTC (0700 DST) 25 AUG Sfc chart Sfc chart Episode AM Episode AM Not much detail Not much detail Similar to day b/f & after Similar to day b/f & after
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D-01 MM5 WINDS
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1200 UTC (0700 DST) 24 AUG 700 mb 700 mb Pre-episode Pre-episode Weak off- shore L (not in NWS) Weak off- shore L (not in NWS) Weak NE flow NE of cityWeak NE flow NE of city
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1200 UTC (0700 DST) 25 AUG 700 mb 700 mb Episode AM Episode AM Stronger off- shore L Stronger off- shore L Stronger NE ff NE of city Stronger NE ff NE of city Will cause con with SB ff Will cause con with SB ff
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1800 DST 23 AUG Sfc chart Sfc chart Pre-episode Pre-episode On-shore SB On-shore SB Not much difference at same time on next 2 days Not much difference at same time on next 2 days Need to see inner domains Need to see inner domains
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D-02 to -04 MM5 Output
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D-05 uMM5 Output
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Daytime (end): 2100 DST 21 AUG Upper L: MM5 Upper L: MM5 Upper R: uMM5 Upper R: uMM5 Lower L: Lower L:MM5-uMM5 uMM5 1 K warmer uMM5 1 K warmer Blob is LU/LC error Blob is LU/LC error
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Nighttime (end): 0900 DST 22 AUG Upper L: MM5 Upper L: MM5 Lower L: uMM5 Lower L: uMM5 Upper R: Upper R:MM5-uMM5 uMM5 2 K cooler uMM5 2 K cooler
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Explanation of uMM5 UHI & UCI Wet soil TI > urban TI > dry soil TI Wet soil TI > urban TI > dry soil TI Urban an area surrounded by wet soil thus has Urban an area surrounded by wet soil thus has Daytime UHI (as urban area warms faster than soil) Daytime UHI (as urban area warms faster than soil) Nighttime UCI (as urban area cools faster than soil) Nighttime UCI (as urban area cools faster than soil) Reverse true with dry rural soil Reverse true with dry rural soil Current results thus consistent with wet rural soil (as expected) around Houston, as uMM5 produced daytime warming & nighttime cooling over urban Houston Current results thus consistent with wet rural soil (as expected) around Houston, as uMM5 produced daytime warming & nighttime cooling over urban Houston
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Ongoing efforts Additional analysis of current simulation results Additional analysis of current simulation results Additional simulations on new 106 CPU cluster Additional simulations on new 106 CPU cluster Use planned 2005-6 Houston field-study data to determine atm and (GIS/RS) urban parameters Use planned 2005-6 Houston field-study data to determine atm and (GIS/RS) urban parameters Develop parameterizations to replace current M-O SBL formulations Develop parameterizations to replace current M-O SBL formulations Link urban CFD & meso-models for Emergency- Response applications Link urban CFD & meso-models for Emergency- Response applications
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