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

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

Following are the CAMx horizontal grid and vertical layer structures used for the Houston-Galveston-Brazoria (HGB) eight-Hour ozone SIP 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 East US 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
East US Domain
(8-Hour SIP)
(-108,2376) (-1584,828) 69 67 36 36
Old Regional Domain
(1-Hour SIP MCR)
(-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
HGB8H CAMx Domain


Vertical Layer Structure

MM5
Layer
Layer
Top
(m AGL)
East US and East Texas Domains HGBPA, HGB, and BPA 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.