Name	Notation	Description	Types	Status
Surface	1		Concept	stable
Standard level	2		Concept	stable
Tropopause level	3		Concept	stable
Maximum wind level	4		Concept	stable
Significant temperature level	5		Concept	stable
Significant humidity level	6		Concept	stable
Significant wind level	7		Concept	stable
Beginning of missing temperature data	8		Concept	stable
End of missing temperature data	9		Concept	stable
Beginning of missing humidity data	10		Concept	stable
End of missing humidity data	11		Concept	stable
Beginning of missing wind data	12		Concept	stable
End of missing wind data	13		Concept	stable
Top of wind sounding	14		Concept	stable
Level determined by regional decision	15		Concept	stable
Pressure level originally indicated by height as the vertical coordinate	17		Concept	stable