This table lists the possible values for leveltype1 or leveltype2 and the interpretation of the corresponding numerical value l1 or l2. More...

This table lists the possible values for leveltype1 or leveltype2 and the interpretation of the corresponding numerical value l1 or l2.

Leveltype values in the range 0-255 can be used for defining either a single level (leveltype1) or a surface delimiting a layer (leveltype1 and leveltype2) with any meaningful combination of leveltypes; values of leveltype >255 have a special use for encoding cloud values in SYNOP reports and they do not strictly define physical surfaces.

The idea is borrowed from the GRIB edition 2 fixed surface concept and the values for leveltype coincide with the GRIB standard where possible.

leveltype   Meaning                                unit/contents of l1/l2

0           Reserved

1           Ground or Water Surface

2           Cloud Base Level

3           Level of Cloud Tops

4           Level of 0C Isotherm

5           Level of Adiabatic Condensation Lifted
            from the Surface

6           Maximum Wind Level

7           Tropopause

8           Nominal Top of the Atmosphere          DB-All.e encodes the
                                                   channel number of polar
                                                   satellites in L1

9           Sea Bottom

10-19       Reserved

20          Isothermal Level                       K/10

21-99       Reserved

100         Isobaric Surface                       Pa

101         Mean Sea Level

102         Specific Altitude Above Mean Sea Level mm

103         Specified Height Level Above Ground    mm

104         Sigma Level

105         Hybrid Level

106         Depth Below Land Surface               mm

107         Isentropic (theta) Level               K/10

108         Level at Specified Pressure Difference Pa
            from Ground to Level

109         Potential Vorticity Surface            10-9 K m2 kg-1 s-1

110         Reserved

111         Eta (NAM) Level (see note below)       1/10000

112         116 Reserved

117         Mixed Layer Depth                      mm



leveltype   Meaning                                unit/contents of l1/l2

118-159 Res

160         Depth Below Sea Level                  mm

161-191 Res

200         Entire atmosphere (considered as a
            single layer)

201         Entire ocean (considered as a single
            layer)

204         Highest tropospheric freezing level

206         Grid scale cloud bottom level

207         Grid scale cloud top level

209         Boundary layer cloud bottom level

210         Boundary layer cloud top level

211         Boundary layer cloud layer

212         Low cloud bottom level

213         Low cloud top level

214         Low cloud layer

215         Cloud ceiling

220         Planetary Boundary Layer

222         Middle cloud bottom level

223         Middle cloud top level

224         Middle cloud layer

232         High cloud bottom level

233         High cloud top level

234         High cloud layer

235         Ocean Isotherm Level                   K/10

240         Ocean Mixed Layer

241         Ordered Sequence of Data

242         Convective cloud bottom level

243         Convective cloud top level

244         Convective cloud layer



leveltype   Meaning                                unit/contents of l1/l2

245         Lowest level of the wet bulb zero

246         Maximum equivalent potential
            temperature level

247         Equilibrium level

248         Shallow convective cloud bottom level

249         Shallow convective cloud top level

251         Deep convective cloud bottom level

252         Deep convective cloud top level

253         Lowest bottom level of supercooled
            liquid water layer

254         Highest top level of supercooled
            liquid water layer

256         Clouds

257         Information about the station that
            generated the data

258         (use when ltype1=256) Cloud Data
            group, L2 = 1 low clouds, 2 middle
            clouds, 3 high clouds, 0 others

259         (use when ltype1=256) Individual cloud
            groups, L2 = group number

260         (use when ltype1=256) Cloud drift, L2
            = group number

261         (use when ltype1=256) Cloud elevation,
            L2 = group number; (use when
            ltype1=264) L2 = swell wave group
            number

262         (use when ltype1=256) Direction and
            elevation of clouds, L2 is ignored

263         (use when ltype1=256) Cloud groups
            with bases below station level, L2 =
            group number

264         Waves