Simulations%20for%20a%20Houston%20ozone%20episode%20

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Simulations for a Houston ozone episode the NYC
DHS MSG tracer study with an urbanized MM5

• R. Bornstein, R. Balmori
• E. Weinroth, H. Taha
• San Jose State University
• San Jose, CA
• pblmodel_at_hotmail.com
• Presented at
• AMS Urban-Coastal Conference
• Sept 2007

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Acknowledgements

• Data
• S. Burian, J. Ching
• TCEQ, USFS
• D. Byun
• Urbanization scheme of
• A. Martilli
• S. Dupont
• Funds
• Past NSF, USAID, DHS
• Pending DTRA

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OUTLINE

• Introduction
• Current uMM5 Applications
• Houston ozone
• NYC tracer study
• Future uWRF
• Conclusion

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Recent Meso-met Model Urbanization

• Need to urbanize momentum, thermo , TKE
• surface SfcBL diagnostic-Eqs.
• PBL prognostic-Eqs.
• Start veg-canopy model (Yamada 1982)
• Veg-param replaced with GIS/RS urban-param/data
• Brown and Williams (1998)
• Masson (2000)
• Martilli et al. (2001) in TVM/URBMET
• Dupont, Ching, et al. (2003) in EPA/MM5
• Taha et al. (2005), Balmori et al. (2006) in
  uMM5
• detailed input urban-parameters as f(x,y) for
  our two applications

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uMM5 for Houston

• Goal Accurate urban/rural temps winds for Aug
  2000 O3 episode via
• uMM5
• Houston LU/LC urban morphology parameters from
  S. Burian
• TexAQS2000 field-study data
• USFS urban-reforestation scenarios ?
• UHI O3 changes

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uMM5 Simulation period 22-26 August 2000

• Model configuration
• 5 domains 108, 36, 12, 4, 1 km
• (x, y) grid points
• (43x53, 55x55, 100x100, 136x151, 133x141
• full-s levels 29 in D 1-4 49 in D-5 lowest ½
  s-level7 m
• 2-way feedback in D 1-4
• Parameterizations/physics options
• gt Grell cumulus (D 1-2) gt ETA or MRF PBL (D
  1-4)
• gt Gayno-Seaman PBL (D-5) gt Simple ice
  moisture,
• gt urbanization module NOAH LSM gt RRTM
  radiative cooling
• Inputs
• gt NNRP Reanalysis fields, ADP obs data
• gt Burian morphology from LIDAR building-data
  in D-5
• gt LU/LC modifications (from Byun)

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D-5 UTC episode-day obs of meso O3
transport-patterns influences of sea breeze
UHI-convergence

• GC influences small
• Air-mass movement
• First along-shore (to west) from flow along
• N-edge of cold-core atm-low
• Then Ship-Channel to Houston by
• Bay Breeze UHI-convergence ? max O3
• Finally to NW of Houston by Gulf Breeze

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Episode-day Synoptics 8/25, 12 UTC (08 DST)
Surface
700 hPa
700 hPa sfc GC Hs at weakest (no gradient)
over Texas ? meso-scale forcing (sea breeze UHI
convergence) dominates
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MM5 episode day, 3 PM ( all graphs flag 5
m/s)gt D1 reproduces weak GC p-grad flowgt
D-2 weak coastal-L gt D-3 well-formed L ?
along-shore V
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Domain 4 (3 PM) cyclone off-Houston only on
O3-day (25th)
? Episode day
L
L
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Urbanized Domain 5 near-sfc 3-PM V, 4-days
Hot
Cool

• Episode
• day

Cold-L
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Along-shore flow, 8/25 (episode day) obs at 1500
UTC vs uMM5 (D-5) at 2000 UTC
D-5 (red box) uMM5 captured HGA obs of
along-shore flow (from SST- BC cold-low)
C
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1 km uMM5 Houston UHI 8 PM, 21 Aug

• Upper L MM5 UHI (2.0 K)
• Upper R uMM5 UHI (3.5 K)
• Lower L (uMM5-MM5) UHI

LU/LC error
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8/23 Daytime 2-m UHI obs vs uMM5 (D-5)
H
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UHI-Induced Convergence obs vs. uMM5
OBSERVED
uMM5
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• Base-case (current)
• veg-cover (0.1s)
• urban min (red)
• rural max (green)

min
Modeled changes of veg-cover (0.01s) gt
Urban-reforestation (green) gt Rural-deforestation
(purple)
max increase
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Run 12 (urban reforestation) minus Run 10 (base
case) 2-m ?T at 4 PMreforested central
urban-area cools surrounding deforested
rural-areas warm
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DUHI(t) for Base-case minus Runs 15-18

• UHI Average-T in urban-box minus that in
  rural-box
• Runs 15-18 different urban re-forestation
  scenarios
• DUHIRun-17 UHI minus Run-13 UHI (max effect)
• Reduced UHI ? lower max-O3 (not shown) ?
• EPA emission-reduction credits ? saved

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uMM5 for NYC DHS MSG UDS

• Goal Accurate urban/rural temps winds
• for 9-15 March 05 tracer releases via
• uMM5
• NYC LU/LC urban morphology
• parameters from S. Burian
• DHS MSG UDS field-study data
• met
• tracer

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Obs of UDS Tracer Periods

• GC influences during tracer periods
• Midtown weak, slow synoptic speed
• MSG strong, fast synoptic speeds
• Sea breeze UHI influences
• Midtown strong, with UHI-convergence
• MSG weak
• Urban-barrier influences
• Midtown weak
• MSG strong, with urban barrier divergence
• Modeling studies by
• Midtown Pullen, Holt, Thompson at NRL
• MSG This presentation

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NYC uMM5 DHS UDS MSG 9-15 March 05

• Model configuration
• 4 domains 36, 12, 4, 1 km
• (x, y) grid points
• (110x85, 91x91, 91x91, 33x33)
• full-s levels 29 in D 1-3 48 in D-4 lowest ½
  s-level7 m
• 2-way feedback in D 1-3
• Parameterizations/physics options
• gt Grell cumulus (D 1-2) gt ETA or MRF PBL (D
  1-4)
• gt Gayno-Seaman PBL (D-5) gt Simple ice
  moisture,
• gt urbanization module NOAH LSM gt RRTM
  radiative cooling
• Inputs
• gt NNRP Reanalysis fields, ADP obs data
• gt Burian morphology from LIDAR building-data
  in D-5
• gt LU/LC modifications (from Byun)

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D03
4 MM5 domains
D04
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1900 UTC, 3/11/05, MM5 Domain 3 Sfc-T(K)
synoptic wave-cyclone V ( flag 5 m/s)
C
W
W
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Concurrent Domain-4 uMM5 Streamlines z 60 m
AGL A-B is plane of following x-section
Downwind convergence
A
Slowing divergence
B
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Concurrent Domain-4 uMM5 Streamlines Speed
(purple lines, m/s) at 60 (left) 700 (right) m
AGL Note z-cells from urban-induced con-
divergence
700 m
60 m
A
A
B
B
1000 m
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Concurrent Domain 4 uMM5 Speed (m/s, where flag
5 m/s) at 60 (left) 700 (right) m AGL
slow
slow
fast
fast
Note large urban z0 ? speed-min downwind of
Manhattan Brooklyn (this is high-speed, non-UHI
period)
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Concurrent domain 4 uMM5 Div (1/s) Wind (flag
5 m/s) at 60 (left) 700 (right) m AGL
D
C
D
C
D
D
Note convergence (C) over Manhattan, as roughness
slows wind Also compensating divergence (D)
around convergence area
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Concurrent Domain4- uMM5 w (m/s) V (m/s) at
60 (left) and 700 (right) m AGL

-
-
-
-

Note up-motion () over Manhattan conv-area (of
previous fig) compensating down-motion (-) in
div-area around Manhattan
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Pending uWRF

• uWRF with NCAR (F. Chen) for DTRA
• Martilli-Dupont urbanization
• Burian lidar urban-parameters as f(x,y)
• Taha stat-generalization of Burian
  urban-parameters for areas w/o lidar-obs
• Freedman PBL-turbulence scheme
• Zilitinkevich SfcBL stability-functions, zoh,
  etc.
• Steyn diagnostic hi(x,y) scheme
• SST (x,y,t) from J. Pullen

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SJSU MM5 or uMM5 met output fields are available

• for ozone (design-day cases) and/or
• 4-D BCs for CFD /or quick ER models for
• SFBA (MM5)
• Houston (uMM5)
• NYC (uMM5)
• LA Basin (MM5)
• Israel (RAMS MM5)

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ThanksQuestions?