MLS_L2_HNO3

Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of MLS_L2_HNO3 data.

field name	type	dimensions	unit	description
datetime	double	{time}	[seconds since 2000-01-01]	time of the measurement
longitude	double	{time}	[degree_east]	tangent longitude
latitude	double	{time}	[degree_north]	tangent latitude
pressure	double	{vertical}	[hPa]	pressure per profile level
HNO3_volume_mixing_ratio	double	{time, vertical}	[ppv]	HNO3 volume mixing ratio
HNO3_volume_mixing_ratio_uncertainty	double	{time, vertical}	[ppv]	uncertainty of the HNO3 volume mixing ratio
HNO3_volume_mixing_ratio_validity	int32	{time, vertical}		quality flag for the HNO3 volume mixing ratio
index	int32	{time}		zero-based index of the sample within the source product

Mapping description

Bits 4 to 9 and 11 to 14 in the quality flag denote a specific error condition while bits 0 to 2 denote the severity (bit 0 error, bit 1 warning, bit 2 comment).

Bits 4 to 9 denote the MLS status (bit 4 HICLOUD, bit 5 LOWCLOUD, bit 6 NO_APRIORI_T, bit 7 NUM_ERROR, bit 8 TOO_FEW_RAD, bit 9 GLOB_FAILURE).

Bits 11 to 14 denote specific checks as specified in the EOS MLS data quality document (the pressure range, quality and convergence thresholds come from table 1.1.1 in issue 4.2 of that document): Bit 11 denotes pressure out of range, bit 12 denotes quality below threshold, bit 13 denotes convergence above threshold and bit 14 denotes a negative precision. Also, if any of the bits 11 to 14 is set, bit 0 is automatically set.

Bits 15 and 16 denote the results of checks that are only performed for the HNO3 product. Bit 15 is set if the pressure is at most 68 hPa and the quality flag is not zero. Bit 16 is set if either the pressure is at least 316 hPa and the volume mixing ratio is less than -2.0 or the pressure is between 68 hPa and 215 hPa and the volume mixing ratio is less than -1.2. Again, if any of the bits 15 and 16 is set, bit 0 is automatically set.

The table below details where and how each variable was retrieved from the input product.

field name	mapping description
datetime	path	/HDFEOS/SWATHS/HNO3/Geolocation_Fields/Time[]
	description	the time converted from TAI93 to seconds since 2000-01-01T00:00:00
longitude	path	/HDFEOS/SWATHS/HNO3/Geolocation_Fields/Longitude[]
latitude	path	/HDFEOS/SWATHS/HNO3/Geolocation_Fields/Latitude[]
pressure	path	/HDFEOS/SWATHS/HNO3/Geolocation_Fields/Pressure[]
HNO3_volume_mixing_ratio	path	/HDFEOS/SWATHS/HNO3/Data_Fields/L2gpValue[]
HNO3_volume_mixing_ratio_uncertainty	path	/HDFEOS/SWATHS/HNO3/Data_Fields/L2gpPrecision[]
HNO3_volume_mixing_ratio_validity	path	/HDFEOS/SWATHS/HNO3/Data_Fields/Status[]