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Houston-Galveston-Brazoria 8-Hour Ozone SIP Modeling (2000 Episode): MM5 Modeling Domain

Meteorological model MM5 modeling domain horizontal grid and vertical layer structures for the Houston-Galveston-Brazoria 8-hour ozone SIP (2000 episode).

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

Horizontal Grid Structure

The MM5 modeling domain is defined with 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 Regional Domain, the East Texas Domain, the Houston-Galveston-Brazoria-Beaumont-Port Arthur (HGBPA) Domain, and the optional Houston-Galveston Bay (HG) Domain.

Domain Range (km) Number of Grid Points Cell Size (km)
Easting Northing Easting Northing Easting Northing
Continental (-2808,2808) (-2268,2268) 53 43 108 108
Regional (-972,2160) (-1728,972) 88 76 36 36
East Texas (-72,1116) (-1548,-360) 100 100 12 12
HGBPA (216,816) (-1356,-816) 151 136 4 4
HG (424,520) (-1156,-1076) 97 81 1 1

HGB SIP MCR MM5 Modeling Domain
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.

MM5 layers