# CODE TABLE 3 Fixed levels or layers for which the data are included
0 0 Reserved
1 sfc Surface (of the Earth, which includes sea surface)
2 sfc Cloud base level
3 sfc Cloud top level
4 sfc 0 deg (C) isotherm level
5 5 Adiabatic condensation level (parcel lifted from surface)
6 6 Maximum wind speed level
7 7 Tropopause level
8 sfc Nominal top of atmosphere
9 9 Sea bottom
# 10-19 Reserved
20 20 Isothermal level Temperature in 1/100 K
# 21-99 Reserved
100 pl Isobaric level pressure in hectoPascals (hPa) (2 octets)
101 101 Layer between two isobaric levels pressure of top (kPa) pressure of bottom (kPa)
102 sfc Mean sea level 0 0
103 103 Fixed height level height above mean sea level (MSL) in meters
104 104 Layer between two specfied altitudes above mean sea level - altitude of top, altitude of bottom (hm)
105 sfc Fixed height above ground height in meters (2 octets)
106 106 Layer between two height levels above ground - height of top, height of bottom (hm)
107 107 Sigma level sigma value in 1/10000 (2 octets)
108 108 Layer between two sigma levels sigma value at top in 1/100 sigma value at bottom in 1/100
109 ml Hybrid level level number (2 octets)
110 ml Layer between two hybrid levels level number of top level number of bottom
111 sfc Depth below land surface centimeters (2 octets)
112 sfc Layer between two depths below land surface - depth of upper surface, depth of lower surface (cm)
113 pt Isentropic (theta) level Potential Temp. degrees K (2 octets)
114 114 Layer between two isentropic levels 475K minus theta of top in Deg. K 475K minus theta of bottom in Deg. K
115 115 Level at specified pressure difference from ground to level hPa (2 octets)
116 116 Layer between two levels at specified pressure differences from ground to levels pressure difference from ground to top level hPa pressure difference from ground to bottom level hPa
117 pv Potential vorticity surface 10-9 K m2 kg-1 s-1
# 118 Reserved
119 119 ETA level: ETA value in 1/10000 (2 octets)
120 120 Layer between two ETA levels: ETA value at top of layer in 1/100, ETA value at bottom of layer in 1/100
121 121 Layer between two isobaric surfaces (high precision) 1100 hPa minus pressure of top, in hPa 1100 hPa minus pressure of bottom, in hPa
# 122-124 Reserved
125 125 Height level above ground (high precision) centimeters (2 octets)
# 126-127 Reserved
128 128 Layer between two sigma levels (high precision) 1.1 minus sigma of top, in 1/1000 of sigma 1.1 minus sigma of bottom, in 1/1000 of sigma
# 129-140 Reserved
141 141 Layer between two isobaric surfaces (mixed precision) pressure of top, in kPa 1100hPa minus pressure of bottom, in hPa
# 142-159 Reserved
160 dp Depth below sea level meters (2 octets)
# 161-199Reserved
200 sfc Entire atmosphere considered as a single layer 0 (2 octets)
201 201 Entire ocean considered as a single layer 0 (2 octets)
# 202-209 Reserved
210 pl Isobaric surface (Pa) (ECMWF extension)
# 211-254 Reserved for local use
255 255 Indicates a missing value
