MLS_L2_CH3OH

Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of MLS_L2_CH3OH 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

CH3OH_volume_mixing_ratio

double

{time, vertical}

[ppv]

CH3OH volume mixing ratio

CH3OH_volume_mixing_ratio_uncertainty

double

{time, vertical}

[ppv]

uncertainty of the CH3OH volume mixing ratio

CH3OH_volume_mixing_ratio_validity

int32

{time, vertical}

quality flag for the CH3OH 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.x-4.0 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.

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

field name

mapping description

datetime

path

/HDFEOS/SWATHS/CH3OH/Geolocation_Fields/Time[]

description

the time converted from TAI93 to seconds since 2000-01-01T00:00:00

longitude

path

/HDFEOS/SWATHS/CH3OH/Geolocation_Fields/Longitude[]

latitude

path

/HDFEOS/SWATHS/CH3OH/Geolocation_Fields/Latitude[]

pressure

path

/HDFEOS/SWATHS/CH3OH/Geolocation_Fields/Pressure[]

CH3OH_volume_mixing_ratio

path

/HDFEOS/SWATHS/CH3OH/Data_Fields/L2gpValue[]

CH3OH_volume_mixing_ratio_uncertainty

path

/HDFEOS/SWATHS/CH3OH/Data_Fields/L2gpPrecision[]

CH3OH_volume_mixing_ratio_validity

path

/HDFEOS/SWATHS/CH3OH/Data_Fields/Status[], /HDFEOS/SWATHS/CH3OH/Data_Fields/Quality[], /HDFEOS/SWATHS/CH3OH/Data_Fields/Convergence[], /HDFEOS/SWATHS/CH3OH/Data_Fields/L2gpPrecision[], /HDFEOS/SWATHS/CH3OH/Geolocation_Fields/Pressure[]

description

see generic mapping description