Edits agreed by the CDM_OBS Governance group - 24th April 2025

tables/observations_fields.dat

@@ -18,3 +18,6 @@ field_id	field_name	kind	description
 17	wl code	2	WCode to designate the wavelength pair(s) used for total ozone measurement.
 18	obs code	2	Code to designate the type of total ozone measurement.
 19	m mu	2	The harmonic mean of the relative slant path through the ozone layer at 22Km for each of the observations used to compute the daily value. 
+20	instrument_viewing_azimuth_angle	2	The azimuth viewing direction of the instrument using north as the reference plane and increasing clockwise (0 for north, 90 for east and so on)
+21	instrument_viewing_zenith_angle	2	The zenith viewing direction of the instrument in degrees between viewing angle and vertical.
+22	sample temperature	2	  Temperature measured inside the instrument where gas concentration is sampled.

tables/observed_variable.dat

@@ -177,3 +177,16 @@ variable	parameter_group	domain	sub_domain	name	units	description
 188	temperature	atmospheric		hourly maximum soil temperature	K	Lot 1 is using Ts - WMO abbrev.
 189	temperature	atmospheric		hourly minimum soil temperature	K	Lot 1 is using Ts - WMO abbrev.
 190				precipitable water column era5	kg m-2	TBD (GNSS variable)
+191	methane	atmospheric	upper-air	methane_total_column	mol/m^2	retrieved total vertical CH4 column between boundaries of the altitude grid. The multiplication factor to convert mol/m2 to molec/cm2 is 6.02214×10^19
+192	methane	atmospheric	upper-air	methane_volume_mixing_ratio	ppmv	vertical CH4 concentration profile from solar absorption measurements 
+193	methane	atmospheric	upper-air	methane_partial_column	mol/m^2	CH4 partial column concentration in the considered retrieval layer. The multiplication factor to convert mol/m2 to molec/cm2 is 6.02214×10^19.
+194	carbon monoxide	atmospheric	upper-air	carbon_monoxide_total_column	mol/m^2	retrieved total vertical CO column between boundaries of the altitude grid. The multiplication factor to convert mol/m2 to molec/cm2 is 6.02214×10^19.
+195	carbon monoxide	atmospheric	upper-air	carbon_monoxide_partial_column	mol/m^2	CO partial column concentration in the considered retrieval layer. The multiplication factor to convert mol/m2 to molec/cm2 is 6.02214×10^19.
+196	carbon monoxide	atmospheric	upper-air	carbon_monoxide_volume_mixing_ratio	ppmv	vertical CO concentration profile from solar absorption measurements 
+197	ozone	atmospheric	upper-air	ozone_total_column_air_mass_factor	1	The Air Mass Factor (AMF) associated with the total vertical column of the target gas retrieved from zenith DOAS measurements; it is defined as the ratio between the Slant Column Density (SCD) and the Vertical Column Density (VCD) of the gas AMF=SCD/VCD. The AMF depends on the optical path length, the vertical distribution of absorbing trace gases in the atmosphere, the Earth's surface reflectivity (albedo), and other factors.
+198	ozone	atmospheric	upper-air	ozone_partial_column	mol/m^2	O3 partial column concentration in a considered vertical layer. The multiplication factor to convert mol/m2 to molec/cm2 is 6.02214×10^19
+199	ozone	atmospheric	upper-air	ozone_slant_column	mol/m^3	Zenith slant column density of target gas corresponding to the observation report timestamp. The multiplication factor to convert mol/m3 to molec/cm3 is 6.02214×10^17.
+200	clouds	atmospheric	upper-air	cloud conditions	coded	Sky conditions; Possible Values: clear-sky; thin clouds; thick clouds; broken clouds; [empty]. [empty] means that the cloud retrieval is not successful, not possible or missing. 
+201	ozone, CH4, CO, HCOCH, NO2	atmospheric	surface; upper-air	solar_azimuth_angle	degrees	Solar azimuth angle is the horizontal angle between the line of sight to the sun and a reference direction which is often due north. The angle is measured clockwise.
+202	ozone	atmospheric	upper-air	ozone_reference_total_ozone	DU	Daily value of total column ozone amount defined as the 'best representative value' in the order of Direct Sun (DS), Zenith Cloud (ZS) and Focused Moon (FM). The multiplication factor to convert mol/m^2 to DU is 2241.15.
+

tables/uncertainty_type.dat

@@ -6,3 +6,11 @@ uncertainty type	name	description	reference
 5	total	The total uncertainty is the sum in quadrature of all the contributions (systematic, quasi-systematic and statistical) to the uncertainty budget.	\hspace{10 mm}	
 6	ozone_partial_pressure_total_uncertainty	Total uncertainty in the calculation of the ozone partial pressure as a composite of the individual uncertainties contribution. Uncertainties due to systamtic bias are assumed as random and following a random normal distribution. The uncertainty calculation also accounts for the increased uncertainty incurred by homogenizing the data record.	\hspace{10 mm}	
 7	ozone_partial_pressure_percentage_uncertainty	Percentage total uncertainty in the calculation of the ozone partial pressure as a composite of the individual uncertainties contribution. Uncertainties due to systamtic bias are assumed as random and following a random normal distribution. The uncertainty calculation also accounts for the increased uncertainty incurred by homogenizing the data record.	\hspace{10 mm}	
+8	negative_random_uncertainty	Random uncertainties are the uncertainty contributions due to random effects causing random errors that cannot be corrected for in a single measured value, even in principle, because the effect is stochastic. According to the GUM, while uncertainty is typically expressed as a standard deviation and assumed to be symmetric, it may become asymmetric in cases involving non-linear measurement models or non-Gaussian input distributions.	
+9	positive_random_uncertainty	Random uncertainties are the uncertainty contributions due to random effects causing random errors that cannot be corrected for in a single measured value, even in principle, because the effect is stochastic. According to the GUM, while uncertainty is typically expressed as a standard deviation and assumed to be symmetric, it may become asymmetric in cases involving non-linear measurement models or non-Gaussian input distributions.	
+10	negative_systematic_uncertainty	Systematic errors which, although removable in principle, cannot be corrected in practice. Systematic uncertainties are the uncertainty contributions due to systematic effects which, although they can be corrected in principle, cannot be corrected in practice. In other words, systematic. Negative uncertainty refers to the systematic errors  (correlated in time) which generates a negative bias.	
+11	positive_systematic_uncertainty	Systematic errors which, although removable in principle, cannot be corrected in practice. Systematic uncertainties are the uncertainty contributions due to systematic effects which, although they can be corrected in principle, cannot be corrected in practice. In other words, systematic. Positive uncertainty refers to the systematic errors  (correlated in time) which generates a  positive bias.	
+12	negative_quasisystematic_uncertainty	The quasi-systematic uncertainties are related to the estimates of errors which are random at high temporal resolution but they becomes correlated between measurements at smaller resolutions. Negative uncertainty refers to the component correlated in time which generates a  negative bias that cannot be corrected in practice.	
+13	positive_quasisystematic_uncertainty	The quasi-systematic uncertainties are related to the estimates of errors which are random at high temporal resolution but they becomes correlated between measurements at smaller resolutions. Positive uncertainty refers to the component correlated in time which generates a positive bias that cannot be corrected in practice.	
+14	negative_total_uncertainty	The total uncertainty is the sum in quadrature of all the contributions (systematic, quasi-systematic and statistical) to the uncertainty budget. Negative uncertainty refers to square combination of the random component and the component correlated in time which generates a  negative bias that cannot be corrected in practice.	
+15	positive_total_uncertainty	The total uncertainty is the sum in quadrature of all the contributions (systematic, quasi-systematic and statistical) to the uncertainty budget. Positive uncertainty refers to square combination of the random component and the component correlated in time which generates a positive bias that cannot be corrected in practice."	

tables/units.dat

@@ -46,7 +46,9 @@ units	name	abbreviation	base_units
 230	week		NULL
 231	year	a	NULL
 300	per cent	\%	NULL
-301	parts per thousand	0/00	NULL
+301	parts per thousand	ppt	NULL
+302	parts per million	ppm	NULL
+303	parts per million by volume	ppmv	NULL
 310	eighths of cloud	okta	NULL
 320	degrees true	deg	NULL
 321	degrees per second	deg/s	NULL