#Code:table:4.5: Fixed surface types and units
0:0:Reserved
1:sfc:Ground or water surface:none:SFC
2:2:Cloud base level:none:CBL
3:3:Level of cloud tops:none:CTL
4:4:Level of 0o C isotherm:none:0DEG
5:5:Level of adiabatic condensation lifted from the surface:none:ADCL
6:6:Maximum wind level:none:MWSL
7:7:Tropopause:none:TRO
8:sfc:Nominal top of the atmosphere:none:NTAT
9:9:Sea bottom:none:SEAB
10:10:Entire Atmosphere:none:EATM
11:11:Cumulonimbus Base:m:CB
12:12:Cumulonimbus Top:m:CT
13:13:Lowest level where vertically integrated cloud cover exceeds the specified percentage (cloud base for a given percentage cloud cover):%:BCC
14:14:Level of free convection:none:LFC
15:15:Convection condensation level:none:CCL
16:16:Level of neutral buoyancy or equilibrium:LNB
# 17-19 Reserved
20:20:Isothermal level:K:TMPL
21:21:Lowest level where mass density exceeds the specified value (base for a given threshold of mass density):kg m-3:BMD
22:22:Highest level where mass density exceeds the specified value (top for a given threshold of mass density):kg m-3:TMD
23:23:Lowest level where air concentration exceeds the specified value (base for a given threshold of air concentration:Bq m-3:BAC
24:24:Highest level where air concentration exceeds the specified value (top for a given threshold of air concentration):Bq m-3:TAC
#21-99 Reserved
100:pl:Isobaric surface:Pa:ISBL
101:sfc:Mean sea level:Pa:MSL
102:102:Specific altitude above mean sea level:m:AMSL
103:sfc:Specified height level above ground:m:HTGL
104:104:Sigma level (sigma value):none:SIGL
105:105:Hybrid level:none:HYBL
106:sfc:Depth below land surface:m:DBLL
107:pt:Isentropic (theta) level:K:THEL
108:108:Level at specified pressure difference from ground to level:Pa:SPDL
109:pv:Potential vorticity:K m2 kg-1 s-1:PVL
110:110:Reserved
111:111:Eta level:Eta value:ETAL
# 112 Reserved
113:113:Logarithmic hybrid level:none:LHBYL
114:114:Snow level:Numeric:SNOWL
115:115:Sigma height level:Numeric:SHL
#116 reserved
117:117:Mixed layer depth:m:MIXL
118:118:Hybrid Height Level:numeric:HHL
119:119:Hybrid Pressure Level:numeric:HPL
# 120-149 Reserved
150:150:Generalized Vertical Height Coordinate:numeric:GVHC
151:151:Soil level:numeric:SL
160:160:Depth below sea level:m:DBSL
161:161:Depth Below Water Surface:m:DBWS
162:162:Lake or River Bottom:none:LRB
163:163:Bottom Of Sediment Layer:none:BSL
164:164:Bottom Of Thermally Active Sediment Layer:none:BTASL
165:165:Bottom Of Sediment Layer Penetrated By Thermal Wave:none:BSLPTW
166:166:Maxing Layer:none:MXL
167:167:Bottom of Root Zone:none:BRZ
168-173	Reserved
174:174:Top Surface of Ice on Sea, Lake or River:none:TSI
175:175:Top Surface of Ice, under Snow, on Sea, Lake or River:none:TSIUS
176:176:Bottom Surface (underside) Ice on Sea, Lake or River:none:BSI
177:177:Deep Soil (of indefinite depth):none:DSOIL
178:178:Reserved
179:179:Top Surface of Glacier Ice and Inland Ice:none:TSGII
180:180:Deep Inland or Glacier Ice (of indefinite depth):none:DIGI
181:181:Grid Tile Land Fraction as a Model Surface:none:GTLF
182:182:Grid Tile Water Fraction as a Model Surface:none:GTWF
183:183:Grid Tile Ice Fraction on Sea, Lake or River as a Model Surface:none:GTIF
184:184:Grid Tile Glacier Ice and Inland Ice Fraction as a Model Surface:none:GTGIIF
#161-191 Reserved
#192-254 Reserved for local use
200:200:Entire atmosphere (considered as a single layer):none:EATM
201:201:Entire ocean (considered as a single layer):none:EOCN
204:204:Highest tropospheric freezing level:none:HTFL
206:206:Grid scale cloud bottom level:none:GCBL
207:207:Grid scale cloud top level:none:GCTL
209:209:Boundary layer cloud bottom level:none:BCBL
210:210:Boundary layer cloud top level:none:BCTL
211:211:Boundary layer cloud layer:none:BCY
212:212:Low cloud bottom level:none:LCBL
213:213:Low cloud top level:none:LCTL
214:214:Low cloud layer:none:LCY
215:215:Cloud ceiling:none:CCL
220:220:Planetary boundary layer:none:PBL
221:221:Layer between two hybrid levels:none:HYBY
222:222:Middle cloud bottom level:none:MCBL
223:223:Middle cloud top level:none:MCTL
224:224:Middle cloud layer:none:MCY
232:232:High cloud bottom level:none:HCBL
233:233:High cloud top level:none:HCTL
234:234:High cloud layer:none:HCL
235:235:Ocean Isotherm Level (1/10 deg C):1/10 degC:OITL
236:236:Layer between two depths below ocean surface:none:OLYR
237:237:Bottom of Ocean Mixed Layer (m):m:OBML
238:238:Bottom of Ocean Isothermal Layer:m:OBIL
239:239:Layer Ocean Surface and 26C Ocean Isothermal Level:none:S26CY
240:240:Ocean Mixed Layer:none:OMXL
241:241:Ordered Sequence of Data:none:OSEQD
242:242:Convective cloud bottom level:none:CCBL
243:243:Convective cloud top level:none:CCTL
244:244:Convective cloud:none:CCY
245:245:Lowest level of the wet bulb zero:none:LLTW
246:246:Maximum equivalent potential temperature level:none:MTHE
247:247:Equilibrium level:none:EHLT
248:248:Shallow convective cloud bottom level:none:SCBL
249:249:Shallow convective cloud top level:none:SCTL
251:251:Deep convective cloud bottom level:none:DCBL
252:252:Deep convective cloud top level:none:DCTL
253:253:Lowest bottom level of supercooled liquid water layer:none:LSCLW
254:254:Highest top level of supercooled liquid water layer:none:HSCLW
255:255:Missing
