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Houston-Galveston-Brazoria Ozone SIP Mid-Course Review Modeling: CAMx Modeling Domain

Photochemical Model CAMx modeling domain horizontal grid and vertical layer structures for the Houston-Galveston-Brazoria ozone SIP Mid-Course Review.

Following are the CAMx horizontal grid and vertical layer structures used for the Houston-Galveston-Brazoria (HGB) ozone SIP Mid-Course Review (MCR) modeling.

Horizontal Grid Structure

The CAMx 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 structure consists a coarse grid regional domain and nested fine grid subdomains: East Texas subdomain, Houston-Galveston-Brazoria-Beaumont-Port Arthur (HGBPA) subdomain, and the optional Houston-Galveston Bay (HGB) and Beaumont-Port Arthur (BPA) subdomains.

Domain Name Range (km) Number of Cells Cell Size (km)
Easting Northing Easting Northing Easting Northing
Regional Domain (-108,1512) (-1584,72) 45 46 36 36
East Texas Subdomain (-12,1056) (-1488,-420) 89 89 12 12
HGBPA Subdomain (356,688) (-1228,-968) 83 65 4 4
HGB Subdomain (431,505) (-1153,-1079) 74 74 1 1
BPA Subdomain (539,613) (-1117,-1043) 74 74 1 1

HGB CAMx Modeling Domain
HGMCR CAMx Domain

Vertical Layer Structure

MM5
Layer
Layer Top
(m AGL)
Regional and East Texas Domains HGBPA, HGB, and BPA Domains
CAMx
Layer
Center
(m AGL)
thickness
(m)
CAMx
Layer
Center
(m AGL)
thickness
(m)
27 5835.9 15 4970.9 1730.0 CAMx Layers II 24 5367.0 937.9 CAMx Layers II
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.