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

Photochemical model CAMx modeling domain: horizontal grid and vertical layer structures for the Houston-Galveston-Brazoria 8-hour ozone SIP revision (2005 and 2006 Episodes).

Following are the CAMx horizontal grid and vertical layer structures used for the 2005/2006 Houston-Galveston-Brazoria eight-hour ozone SIP modeling (HGB8H2).

Horizontal Grid Structure

The CAMx modeling domain is defined in 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 structure consists of a coarse-grid East US domain and nested fine-grid subdomains: East Texas subdomain, Houston-Galveston-Brazoria/Beaumont-Port Arthur (HGB/BPA) subdomain, and the Houston-Galveston (HG) subdomains.

Domain Name Range (km) Number of Cells Cell Size (km) Name in
CAMx
Easting Northing Easting Northing Easting Northing
East US Domain (-108,2376) (-1584,828) 69 67 36 36 eus_36km
East Texas Subdomain (-12,1056) (-1488,-420) 89 89 12 12 etx_12km
HGB/BPA Subdomain (356,688) (-1228,-968) 83 65 4 4 hgbpa_04km
HG Subdomain (394,542) (-1154,-1042) 74 56 2 2 hg_02km

Vertical Layer Structure

MM5
Layer
Layer
Top
(m AGL)
East US and East Texas Domains HGB/BPA and HG Domains
CAMx
Layer
Center
(m AGL)
Thickness
(m)
CAMx
Layer
Center
(m AGL)
Thickness
(m)
38 15179.1 17 12172.9 6012.5 CAMx Layers II 28 13637.9 3082.5 CAMx Layers II
36 12096.6       27 10631.6 2930.0
32 9166.6 16 7501.3 3330.7 26 8063.8 2205.7
29 6960.9       25 6398.4 1125.0
27 5835.9 15 4970.9 1730.0 24 5367.0 937.9
25 4898.0       23 4502.2 791.6
23 4106.4 14 3565.9 1080.0 22 3739.9 733.0
21 3373.5       21 3199.9 347.2
20 3026.3 13 2564.5 922.9 20 2858.3 335.9
19 2690.4       19 2528.3 324.3
18 2366.1       18 2234.7 262.8
17 2103.3 12 1728.1 749.8 17 1975.2 256.2
16 1847.2       16 1722.2 249.9
15 1597.3       15 1475.3 243.9
14 1353.4 11 1210.6 285.2 14 1281.6 143.6
13 1209.8       13 1139.0 141.6
12 1068.2 10 929.3 277.5 12 998.3 139.7
11 928.5       11 859.5 137.8
10 790.6 9 700.0 181.0 10 745.2 90.9
9 699.7       9 654.7 90.1
8 609.7 8 564.9 89.3 8 565.0 89.3
7 520.3 7 476.0 88.5 7 476.1 88.5
6 431.8 6 387.8 87.8 6 387.9 87.8
5 344.0 5 300.4 87.0 5 300.5 87.1
4 256.9 4 213.7 86.3 4 213.8 86.3
3 170.6 3 127.7 85.6 3 127.8 85.6
2 85.0 2 59.4 51.0 2 59.4 51.0
1 33.9 1 16.9 33.9 1 17.0 33.9

Note: AGL - Above ground level.