Level layer

This table lists all the various value combinations to use as a level layer:

	Level type			Meaning			Contents (l1)			Contents (l2)
	0			Reserved
	1			Ground or water surface
	2			Cloud base level
	3			Level of cloud tops
	4			Level of 0$^o$C isotherm
	5			Level of adiabatic condensation lifted from the surface
	6			Maximum wind level
	7			Tropopause
	8			Nominal top of atmosphere
	9			Sea bottom
	10-19			Reserved
	20			Isothermal level			Temperature in 1/100 K
	21-99			Reserved
	100			Isobaric surface			Pressure in hPa
	101			Layer between two isobaric surfaces			Pressure of top in kPa			Pressure of bottom in kPa
	102			Mean sea level
	103			Specified altitude above mean sea level			Altitude in meters
	104			Layer between two specified altitudes above mean sea level			Altitude of top in hm			Altitude of bottom in hm
	105			Specified height above ground			Height in meters
	106			Layer between two specified height levels above ground			Height of top in hm			Height of bottom in hm
	107			Sigma level			Sigma value in 1/10000
	108			Layer between two sigma levels			Sigma value of top in 1/100			Sigma value of bottom in 1/100
	109			Hybrid level			Level number
	110			Layer between two hybrid levels			Level number of top			Level number of bottom
	111			Depth below land surface			Depth in centimeters
	112			Layer between two depths below land surface			Depth of upper surface in cm			Depth of lower surface in cm
	113			Isentropic (theta) level			Potential temperature in K
	114			Layer between two isentropic levels			475 K minus theta of top in K			475 K minus theta of bottom in K
	115			Level at specified pressure difference from ground to level			Pressure difference in hPa
	116			Layer between two levels at specified pressure differences from ground to level			Pressure difference from ground to top level in hPa			Pressure difference from ground to bottom level in hPa
	117			Potential vorticity surface			10-9 K m2 kg-1 s-1
	118			Reserved
	119			ETA* level			ETA value in 1/10000
	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			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			Specified height level above ground (high precision)			Height in centimeters
	126-127			Reserved
	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			Layer between two isobaric surfaces (mixed precision)			Pressure of top in kPa			1100 hPa minus pressure of bottom in hPa
	142-159			Reserved
	160			Depth below sea level			Depth in meters
	161-199			Reserved
	200			Entire atmosphere (considered as a single layer)
	201			Entire ocean (considered as a single layer)
	202-254			Reserved
	256			Cloud levels			0			0=General Cloud Group, 1=CL, 2=CM, 3=CH
	256			Synop cloud group 1			1
	256			Synop cloud group 2			2
	256			Synop cloud group 3			3
	256			Synop cloud group 4			4
	257			Extra anagraphical informations