Observed variable - measurand (atmosphere)
Atmospheric pressure profile
Total lightning density
Lightning density cloud-to-ground
Horizontal wind direction at specified distance from reference surface
Horizontal wind speed at specified distance from reference surface
Cloud amount
Cloud cover
Cloud drop effective radius
Cloud hydrometeor concentration
Effective radius of cloud hydrometeors
Melting layer depth in clouds
PSC occurrence
CH4
CH4 [C-13]
CO2
CO2 [C-13]
CO2 [O-18]
N2O
SF6
SO2F2 (sulphuryl fluoride)
H2O (as a chemical species)
HDO (as a chemical species)
Amount of precipitation
Duration of precipitation
Intensity of precipitation
Occurrence of precipitation during last period (yes/no)
Rate of ice accretion
Type of precipitation
Atmospheric pressure
Characteristic of pressure tendency
Pressure tendency
Beryllium [Be-7]
CO2 [C-14]
Krypton [Kr-85]
Lead [Pb-210]
Radon [Rn-222]
Air temperature (at specified distance from reference surface)
Dew-point temperature (at specified distance from reference surface)
Extreme temperature (min, max) (at specified distance from reference surface)
Temperature profile
Runway visual range
Visibility
Transport calculations (e.g., trajectories)
Turbulence
Turbulence type (low levels and wake vortex)
Humidity (at specified distance from reference surface)
Integrated water vapour
Mass mixing ratio
Object wetness duration
Water vapour pressure
Watervapor profile
Lightning discharge energy
Lightning discharge polarity
Lightning discharge rates
Lightning discharge type (cloud to cloud, cloud to surface)
Surface ozone
Total column ozone
Vertical ozone profile
Past weather
Present weather
Background luminance
Sunshine duration
Surface albedo
UV-B radiation
BrO (bromine monoxide)
C2Cl4 (tetrachloroethene)
C2HCl3 (trichloroethene)
CH2Br2 (dibromomethane)
CH2Cl2 (dichloromethane)
CH3Br (methylbromide)
CH3Cl (methylchloride)
CH3I (methyliodide)
CHBr3 (bromoform)
CHCl3 (chloroform)
COF2 (difluoromethanal, carbonyl fluoride)
ClO (chlorine monoxide)
H2O2 (hydrogen peroxide)
HCl (hydrochloric acid)
HF (hydrofluoric acid)
ROOH
Acidity-Alkalinity
Electric conductivity
Hydrogen ion (H+) or pH
Sulphur (S)
Direction of cloud movement
Gust Speed
Wind (Z component, vertical)
Wind (surface wind direction and speed, horizontal) - deprecated
Upper wind (X, Y components, horizontal)
Aerosol Absorption Optical Depth
Aerosol Extinction Coefficient
Light absorption coefficient, PM1
Light absorption coefficient, PM10
Light absorption coefficient, total aerosol
Light backscattering coefficient, PM1
Light backscattering coefficient, PM10
Light backscattering coefficient, total aerosol
Light scattering coefficient, PM1
Light scattering coefficient, PM10
Light scattering coefficient, total aerosol
Multiwavelength optical depth, total aerosol
Vertical distribution of properties
Cloud ice
Cloud ice (total column)
Cloud ice effective radius
Freezing level height in clouds
Icing potential
CBrClF2 (Halon 1211)
CBrF3 (bromotrifluoromethane, Halon 1301)
C13H10 (9H-fluorene, fluorene), in air
C14H10 (anthracene), PM10
C14H10 (anthracene), in aerosol
C14H10 (anthracene), in air and aerosol
C14H10 (anthracene), in air
C14H10 (phenanthrene), PM10
C14H10 (phenanthrene), in aerosol
C14H10 (phenanthrene), in air
C14H10 (phenanthrene), in air and aerosol
C14H10 (phenanthrene), in wet deposition
C14H10 (phenanthrene), in total precipitation
C16H10 (pyrene), in air and aerosol
C18H12 (Benz(a)anthracene), PM10
C18H12 (Benz(a)anthracene), in aerosol
C18H12 (Benz(a)anthracene), in air
C18H12 (Benz(a)anthracene), in air and aerosol
C18H12 (Benz(a)anthracene), in precipitation
C18H12 (Benz(a)anthracene), in total precipitation
UV Broadband
UV Erythemally weighted
UV Multiband
UV Spectral
Aerosol column burden (mass density)
Aerosol effective radius
Mass concentration (coarse) or Mass PM10
Mass concentration (fine) or Mass PM1
Mass concentration (medium), PM2.5
Mass concentration (size fractionated)
Mass concentration (total aerosol) or Mass TSP
Number concentration
Aerological soundings
Number size distribution, PM10
Number size distribution, total aerosol
Cloud liquid water (CLW)
Cloud liquid water (CLW, total column)
C12H8Cl6 (aldrin), in aerosol
C12H8Cl6 (aldrin), in air
C12H8Cl6 (aldrin), in air and aerosol
C12H8Cl6 (aldrin), in total precipitation
C12H8Cl6 (aldrin), in wet precipitation
C6Cl6 (hexachlorobenzene, HCB), in air
C6H6Cl6 (1,2,3,4,5,6-hexachlorocyclohexane, alpha-lindane, alpha-HCH), in aerosol
C6H6Cl6 (1,2,3,4,5,6-hexachlorocyclohexane, alpha-lindane, alpha-HCH), in air
C6H6Cl6 (1,2,3,4,5,6-hexachlorocyclohexane, alpha-lindane, alpha-HCH), in wet precipitation
C6H6Cl6 (1,2,3,4,5,6-hexachlorocyclohexane, gamma-lindane, gamma-HCH), in air
C6H6Cl6 (1,2,3,4,5,6-hexachlorocyclohexane, gamma-lindane, gamma-HCH), in wet precipitation
Atmospheric density
Ammonia (NH3)
C2H3O5N (peroxyacetylnitrate, PAN)
ClONO2 (chlorine nitrate)
HCN (formonitrile, hydrogen cyanide)
HNO3 (nitric acid)
NO2
NOx
NOy
CCN concentration at single supersaturation
CCN concentration spectra
Hygroscopic growth factor, 110 μm equivalent
Hygroscopic growth factor, 165 μm equivalent
Hygroscopic growth factor, 35 μm equivalent
Hygroscopic growth factor, 50 μm equivalent
Hygroscopic growth factor, 75 μm equivalent
Hygroscopic growth factor, total aerosol
C2F6 (hexafluoroethane, PFC-116)
C3F8 (octafluoropropane, PFC-218)
CF4 (tetrafluoromethane, carbon tetrafluoride, perfluoromethane, PFC-14)
COS (OCS, carbon oxide sulfide, carbonyl sulfide)
CS2 (Carbon disulfide)
SO2
Lightning detection (time and location)
Lightning direction from station
Lightning distance from station
C2H2 (ethyne, acetylene)
C2H2O2 (oxaldehyde, ethanedial)
C2H4 (ethene)
C2H6 (ethane)
C2H6S (dimethylsulfide, DMS)
C3H4 (propyne)
Integrated air samples
C3H4O (prop-2-enal, acrolein)
C3H4O2 (2-oxopropanal, methylglyoxal)
C3H6 (propene)
C3H6O (acetone, propanone)
C3H6O (propanal)
C3H8 (propane)
C4H6 (1,3-butadiene, butadiene)
C4H6O (2-methylprop-2-enal, methacrolein)
C4H6O (but-3-en-2-one, methylvinylketone)
C4H8 (1-butene)
C4H8 (sum of butenes)
C4H8O (butan-2-one, methylethylketone)
C4H8O (butanal isomers)
C5H10 (1-pentene)
C5H10 (2-methyl-1-butene)
C5H10 (2-methyl-2-butene)
C5H10 (3-methyl-1-butene)
C5H10 (cyclopentane)
C5H10 (sum of 1-pentene & 2-methyl-2-butene)
C5H10 (sum of pentenes)
C5H10O (pentanal, valeraldehyde)
C5H12 & C4H8 (sum of 2,2-dimethylpropane & c-2-butene)
C5H12 (2,2-dimethylpropane)
C5H14 (2,3-dimethylbutane)
C5H8 (2-methyl-1,3-butadiene, isoprene)
C5H8 (cyclopentene)
C5Hn (n={10, 8}; sum of 3-methyl-1-butene & cyclopentene)
C5Hn (n={12, 10}; sum of n-pentane & cyclopentane)
C6H12 (cyclohexane)
C6H12 (methylcyclopentane)
C6H12O (hexanal isomers)
C6H14 (2,2-dimethylbutane)
C6H14 (2-methylpentane)
C6H14 (3-methylpentane)
C6H14 (n-hexane)
C6H14 (sum of methylpentanes)
C6H6 (benzene)
C6Hn (n={14, 12}; sum of 3-methylpentane & cyclohexane)
C6Hn (n={14, 12}; sum of 2,2-dimethylbutane & methylcyclopentane
C6Hn (n={14, 12}; sum of 2,3-dimethylbutane & methylcyclopentane
C7H16 (sum of methylhexanes)
C7H6O (benzene carbaldehyde)
C7H8 (toluene)
C8H10 (ethylbenzene)
C8H10 (m-xylene)
C8H10 (o-xylene)
C8H10 (p,m-xylene)
C9H12 (1,2,4-trimethylbenzene)
C9H12 (1,3,5-trimethylbenzene)
CH2O (formaldehyde)
CH3CH2OH (ethanol)
CH3CHO (acetaldehyde, ethanal)
CH3CN (acetonitrile)
CH3OH (methanol)
NMHC
c-C4H8 (cis-2-butene)
c-C5H10 (cis-2-pentene)
i-C4H10 (2-methylpropane, iso-butane)
i-C4H8 (2-methylpropene, iso-butene)
i-C5H12 (2-methylbutane, iso-pentane)
i-C7H16 (2-methylhexane, isoheptane)
n-C4H10 (n-butane)
n-C5H12 (n-pentane)
n-C7H16 (n-heptane)
t-C4H8 (trans-2-butene)
t-C5H10 (trans-2-pentene)
Cloud optical depth
Optical depth of fog
Optical depth within each layer
Short-wave cloud reflectance
Extinction coefficient
Hydrometeor radius
Hydrometeor type
Lithometeor type
Meteorological Optical Range
Obscuration type
Strong acids
Height of cloud base
Height of cloud top
Height of inversion
C2H3Cl2F (1,1-dichloro-1-fluoroethane, HCFC-141b)
C2H3ClF2 (1-chloro-1,1-difluoroethane, HCFC-142b)
C2H3F3 (1,1,1-trifluoroethane, HCFC-143a)
CHClF2 (chlorodifluoromethane, HCFC-22)
Bromide (Br-)
Chloride (Cl-)
Fluoride (F-)
Iodide (I-)
Phosphate (PO4---)
Sulphate (SO4=), corrected
Sulphate (SO4=), total
Calcium (Ca++)
Magnesium (Mg++)
Potassium (K+)
Sodium (Na+)
Type of cloud
Type of high clouds
Type of low clouds
Type of middle clouds
C2H2F4 (1,1,1,2-tetrafluoroethane, HFC-134a)
C2H4F2 (1,1-difluoroethane, HFC-152a)
C2HF5 (pentafluoroethane, HFC-125)
C3H2F6 (1,1,1,2,3,3-hexafluoropropane, HFC-236fa)
C3H3F5 (1,1,1,3,3-Pentafluoropropane, HFC-245fa)
C3HF7 (1,1,1,2,3,3,3-Heptafluoropropane, HFC-227ea)
Special phenomena
C4H5F5 (1,1,1,3,3-pentafluorobutane, HFC-365mfc)
CH2F2 (difluoromethane, HFC-32)
CHF3 (trifluoromethane, HFC-23)
Long-wave radiation (direction unspecified)
Long-wave radiation (downwelling)
Long-wave radiation (upwelling)
Ammonium (NH4+)
Nitrate (NO3-)
State of ground
Nitrite (NO2-)
Diffuse solar radiation
Direct solar radiation
Global solar radiation (downwelling)
Global solar radiation (upwelling)
Acetate (CH3COO-)
Formate (HCOO-)
Propionate (C2H5COO-)
Acidity-Alkalinity, total aerosol
C2Cl2F4 (1,2-dichlorotetrafluoroethane, CFC-114)
C2Cl3F3 (1,1,2-trichloro-1,2,2-trifluoroethane, CFC-113)
C2ClF5 (1-chloro-1,1,2,2,2-pentafluoroethane, CFC-115)
CCl2F2 (dichlorodifluoromethane, CFC-12)
CCl3F (trichlorofluoromethane, CFC-11)
CCl4 (carbon tetrachloride)
CH3CCl3 (1,1,1-trichloroethane)
Aluminium (Al)
Arsenic (As)
Cadmium (Cd)
Chromium (Cr)
Cobalt (Co)
Copper (Cu)
Iron (Fe)
Lead (Pb)
Manganese (Mn)
Mercury (Hg)
Nickel (Ni)
Vanadium (V)
Zinc (Zn)
Chloride (Cl-), PM1
Chloride (Cl-), PM10
Chloride (Cl-), PM2.5
Chloride (Cl-), total aerosol
Fluoride (F-), total aerosol
Sulphate (SO4=), total, PM10
Sulphate (SO4=), total, PM2.5
Elemental carbon (coarse), PM10
Elemental carbon, PM1
Elemental carbon, PM2.5
Total carbon (coarse), PM10
Calcium (Ca++), PM10
Calcium (Ca++), PM2.5
Calcium (Ca++), total aerosol
Magnesium (Mg++), PM10
Magnesium (Mg++), PM2.5
Magnesium (Mg++), total aerosol
Potassium (K+), PM10
Potassium (K+), PM2.5
Potassium (K+), total aerosol
Sodium (Na+), PM10
Sodium (Na+), PM2.5
Sodium (Na+), total aerosol
Ammonia (NH3), PM2.5
Ammonium (NH4+), PM10
Ammonium (NH4+), PM2.5
Ammonium (NH4+), total aerosol
Ammonium nitrate (NH4NO3), total aerosol
Ammonium nitrate (NH4NO3), PM1
Nitrate (NO3-), PM10
Nitrate (NO3-), PM2.5
Nitrate (NO3-), total aerosol
Nitrite (NO2-), total aerosol
Sum of ammonia (NH3) and ammonium (NH4+), in air and aerosol
Sum of nitric acid (HNO3) and nitrate (NO3-), in air and aerosol
Major chemical components (size fractionated)
Major inorganic components (TSP)
Major inorganic components (coarse)
Major inorganic components (fine)
Other chemical components (coarse)
Other chemical components (fine)
C2H3O2- (CH3COO-, acetate), PM1
C2H3O2- (CH3COO-, acetate), in aerosol
C2O4= (oxalate, ethanedioate), PM1
C2O4= (oxalate, ethanedioate), PM10
C2O4= (oxalate, ethanedioate), total aerosol
CH3O3S- (methanesulphonate), PM1
CH3O3S- (methanesulphonate), total aerosol
CHO2- (HCOO-, formate), in aerosol
Carbonaceous-organic material (coarse), PM10
Carbonaceous-organic material (fine)
Titanium (Ti), total aerosol
Aluminium (Al), PM2.5
Aluminium (Al), total aerosol
Antimony (Sb), PM2.5
Antimony (Sb), total aerosol
Arsenic (As), PM10
Arsenic (As), total aerosol
Barium (Ba), PM2.5
Barium (Ba), total aerosol
Bismuth (Bi), PM2.5
Bismuth (Bi), total aerosol
Cadmium (Cd), PM1
Cadmium (Cd), PM10
Cadmium (Cd), PM2.5
Cadmium (Cd), PM2.5 thru PM10
Cadmium (Cd), total aerosol
Cerium (Ce), PM2.5
Cerium (Ce), total aerosol
Chromium (Cr), total aerosol
Cobalt (Co), total aerosol
Copper (Cu), PM10
Copper (Cu), total aerosol
Iron (Fe), total aerosol
Lanthanum (La), PM2.5
Lanthanum (La), total aerosol
Lead (Pb), PM10
Lead (Pb), total aerosol
Lithium (Li), PM2.5
Lithium (Li), total aerosol
Manganese (Mn), PM10
Manganese (Mn), total aerosol
Mercury (Hg), total aerosol
Nickel (Ni), PM10
Nickel (Ni), total aerosol
Phosphorous (P), PM2.5
Phosphorous (P), total aerosol
Rubidium (Rb), PM2.5
Rubidium (Rb), total aerosol
Selenium (Se), total aerosol
Strontium (Sr), PM2.5
Strontium (Sr), total aerosol
Thallium (Tl), PM2.5
Thallium (Tl), total aerosol
Thorium (Th), PM2.5
Thorium (Th), total aerosol
Tin (Sn), PM2.5
Tin (Sn), total aerosol
Uranium (U), PM2.5
Uranium (U), total aerosol
Vanadium (V), PM2.5
Vanadium (V), total aerosol
Zinc (Zn), PM2.5
Zinc (Zn), total aerosol
Aerosol dust concentration (mass)
Aerosol volcanic ash (mass concentration)
Aerosol volcanic ash (Total column)
inapplicable
unknown