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Houston-Galveston-Brazoria 8-Hour Ozone SIP Modeling (2005/2006 Episodes): MM5 Modeling Domain

Meteorological modeling (MM5) domain: horizontal grid and vertical layer structures for the Houston-Galveston-Brazoria 8-hour ozone SIP revision (2005 and 2006 episodes).

Below are the MM5 horizontal grid and vertical layer structures used in the 2006 Houston-Galveston-Brazoria eight-hour ozone SIP modeling (HGB8H2).

Horizontal Grid Structure

The MM5 modeling domain is defined from the Lambert Conformal Conic map projection.

First True Latitude (Alpha): 30ºN
Second True Latitude (Beta): 60ºN
Central Longitude (Gamma): 100ºW
Projection Origin: (100ºW, 40ºN)
Spheroid: Perfect Sphere, Radius = 6370 km

The horizontal modeling domain grid structure consists of a coarse grid continental domain and four nested subdomains: the Continental Domain, U.S. Domain, South U.S. Domain, and East Texas Domain.

Domain Name Range (km) Number of Grid Points Cell Size (km) Domain Number
in MM5
Easting Northing Easting Northing Easting Northing
Continental Domain (-2808,2808) (-2268,2268) 53 43 108 108 1
U.S. Domain (-1296,2160) (-1728,972) 97 76 36 36 2
South U.S. Domain (-648,1080) (-1548,-360) 145 100 12 12 3
East Texas Domain (72,732) (-1380,-648) 166 184 4 4 4

HGB8H2 MM5 Modeling Domain
HGB8H2 MM5 Modeling Domain

Vertical Layer Structure

Layer Sigma Layer Top
(m AGL)
Center
(m AGL)
Thickness
(m)
43 0.000 20806.8 20362.1 889.6
42 0.010 19917.3 19341.4 1151.7
41 0.025 18765.6 18117.9 1295.3
40 0.045 17470.3 16918.8 1103.1
39 0.065 16367.2 15773.2 1188.1
38 0.090 15179.1 14662.7 1032.8
37 0.115 14146.3 13602.4 1087.8
36 0.145 13058.5 12577.6 961.9
35 0.175 12096.6 11596.6 1000.0
34 0.210 11096.7 10587.9 1017.5
33 0.250 10079.1 9622.9 912.6
32 0.290 9166.6 8752.3 828.6
31 0.330 8338.0 7958.1 759.8
30 0.370 7578.2 7269.5 617.3
29 0.405 6960.9 6671.3 579.2
28 0.440 6381.7 6108.8 545.8
27 0.475 5835.9 5577.7 516.3
26 0.510 5319.5 5108.7 421.6
25 0.540 4898.0 4695.9 404.0
24 0.570 4493.9 4299.9 388.0
23 0.600 4105.9 3919.3 373.3
22 0.630 3732.7 3552.8 359.7
21 0.660 3373.0 3199.5 347.1
20 0.690 3025.9 2858.2 335.5
19 0.720 2690.4 2528.1 324.6
18 0.750 2365.8 2234.4 262.8
17 0.775 2103.0 1974.9 256.1
16 0.800 1846.9 1721.9 249.8
15 0.825 1597.0 1475.1 243.9
14 0.850 1353.2 1281.4 143.6
13 0.865 1209.6 1138.8 141.6
12 0.880 1068.0 998.1 139.7
11 0.895 928.3 859.4 137.8
10 0.910 790.5 745.0 90.9
9 0.920 699.6 654.6 90.1
8 0.930 609.5 564.9 89.3
7 0.940 520.2 476.0 88.5
6 0.950 431.7 387.8 87.8
5 0.960 343.9 300.4 87.0
4 0.970 256.9 213.7 86.3
3 0.980 170.5 127.7 85.6
2 0.990 84.9 59.4 51.0
1 0.996 33.9 16.9 33.9
0 1.000 0.0 0.0 0.0
Note: AGL - above ground level.
HGB8H2 MM5 vertical layers