Master Level Type Table 201110130948 current 001 surface surface ground or water surface (the atmosphere's lower boundary, land/sea surface) current 004 isth_lvl_0C isth_lvl_0C level of 0 deg C isotherm current 006 max_wnd_lvl max_wnd_lvl maximum wind level current 007 trpp_lvl trpp_lvl tropopause current 008 atms_top atms_top top of atmosphere (nominal top of atmosphere) current 020 isth_lvl isth_lvl isothermal level current 100 isbr_lvl isbr_lvl isobaric surface (constant pressure) current 101 isbr_lay isbr_lay layer between two isobaric levels current 102 msl msl mean sea level current 103 ht_msl ht_msl height above mean sea level current 105 ht_sfc ht_sfc specific height level above ground (height above earth/sea surface) current 107 sgma_lvl sgma_lvl sigma level current 112 grnd_lay grnd_lay The upper layer of the Earth's ground surface current 113 isnt_lvl isnt_lvl isentropic (theta) level (constant theta) listed 160 dpth_sfc dpth_sfc depth below sea level (surface) current 199 wavelen_sfc wavelen_sfc A wavelength at the earth's surface. The wavelength, in nanometers, appears in the first level, the sfc layer is in the second level. current 200 sky_cvr sky_cvr sky cover (entire atmosphere) current 212 low_cld low_cld low cloud layer deprecated 219 isbr_lvl_pa isbr_lvl_pa isobaric (constant pressure) surface in pascals current 222 mid_cld mid_cld middle cloud layer deprecated 232 hi_cld hi_cld high cloud layer deprecated 241 dpth_ix dpth_ix depth index current 250 flight_lvl flight_lvl an altitude above mean sea level. current 251 flight_lvl flight_lvl altitude above 18,000 feet deprecated 252 flight_lvl flight_lvl layer below 18,000 feet deprecated 253 flight_lvl flight_lvl layer in atmosphere 18,000 feet and above. deprecated