Notation	Name	Description	Status
24	Human observation	Observation of clouds from the Earth's surface by a human obs...	stable
58	(Optical) filter Instrument		stable
59	(Ruler for) rain gauge		stable
60	(Ultra)sonic anemometer		stable
62	Adsorption - scintillation counting		stable
63	Aerovane (wind vane with propeller)		stable
64	Alpha counting		stable
65	Anemometer [general]		stable
66	Aneroid barometer (evacuated capsule)		stable
67	Anion exchange membrane (AEM)		stable
68	Atmometer		stable
69	Atmospherics ('sferics') detection		stable
70	Atomic absorption spectrophotometry (AAS)		stable
71	Atomic emission spectrophotometry (AES)		stable
72	BSRN compliant instrument		stable
73	Barometer, mercury column		stable
74	Barometer, mercury-free column		stable
75	Beta counting		stable
76	Bimetal thermometer		stable
77	Bowen-ratio method		stable
78	Brewer		stable
79	Brewer-GDR		stable
80	Brewer-Mast Sonde		stable
82	Capacitive rain sensor		stable
83	Capillary electrophoresis (CE)		stable
84	Carbon-Iodine Sonde (KC Sonde)		stable
87	Colorimetric titration (Gran method)		stable
88	Colorimetric titration [general]		stable
90	Colorimetry (Saltzman)		stable
91	Colorimetry (thorin)		stable
94	Conductometry		stable
95	Cup anemometer		stable
96	Cup anemometer (3 or 4 cups)		stable
97	Cuvette		stable
98	Denuder		stable
99	Denuder		stable
102	Disdrometer (drop spectrographs)		stable
103	Disjunct eddy covariance method		stable
105	Dissipation method		stable
106	Dobson		stable
107	ECC Sonde		stable
108	Eddy accumulation method		stable
109	Eddy covariance method		stable
110	Electric conductivity (EC meter)		stable
111	Electronic pressure transducer (silicon diaphragm)		stable
112	Estimation from visual observation		stable
113	Evaporation pan and-or tank		stable
114	Faraday cup photochemistry		stable
115	Filter sampling + alpha counting		stable
116	Filter sampling + gamma spectrometry		stable
119	Flame-ionization detector (FID)		stable
120	Flask sampling (analytical method unspecified)		stable
121	Flow injection analyzer (FIA)		stable
123	Flux variance method		stable
125	Gradient method		stable
127	Gravimetry [general]		stable
129	High Performance Liquid Chromatography (HPLC)		stable
130	Hot wire anemometer		stable
132	Hypsometer (water boiling point)		stable
133	ICP-AES		stable
134	ICP-MS		stable
135	Indian Sonde		stable
136	Interferential method		stable
137	Ion Chromatography (IC) [general]		stable
142	Doppler wind lidar	Light detection and ranging (lidar) with Doppler capability (...	stable
143	Raman lidar	Light detection and ranging (lidar) with Raman capability, ty...	stable
144	Liquid-in-glass thermometer (mercury-free)		stable
146	Lysimeter		stable
147	Mass balance method		stable
149	Mercury-in-glass thermometer		stable
150	Microbarometer (dewar)		stable
151	Microtops		stable
152	Microtops		stable
153	Microtops		stable
154	Microwave profiler		stable
155	Microwave radiometry		stable
156	Microwave radiometry		stable
157	NILU_O_2		stable
158	NILU_O_3		stable
166	Ozone sonde (unspecified)		stable
167	Passive Samplers [general]		stable
168	Photoacoustic detection		stable
170	Pluviograph		stable
171	Potassium iodide (KI) method		stable
172	Potentiometry (ion-selective electrode)		stable
173	Potentiometry (pH meter)		stable
174	Pressure balance (piston)		stable
175	Pressure plate (solid blade)		stable
176	Pressure tube		stable
177	Propeller anemometer		stable
179	Pyranometer (measurement of IR radiation)		stable
180	Pyrradiometer (total global, UV+IR)		stable
181	Radio acoustic sounding system (RASS)		stable
182	Radio acoustic sounding system (RASS)		stable
183	Radio detection and ranging (Radar)		stable
184	Radio detection and ranging (Radar) profiler		stable
185	Radiochemical Methods [general]		stable
186	Regener Sonde (chemiluminescence)		stable
188	Resistance thermometer, thermistor		stable
189	SAOZ (UV-vis diode array spectrometer)		stable
190	Scatterometer	Visual range is calculated by measuring the return of light b...	stable
191	Separation + manometric determination		stable
195	Sonic thermometer		stable
196	Sound detection and ranging (Sodar) profiler		stable
197	Sunphotometry-Filter Radiometry		stable
198	Sunshine duration		retired
199	Surface chamber		stable
201	Thermocouple, thermopile		stable
202	Thermometer-Thermoelement		superseded
204	Tipping bucket rain gauge (totalizer)		stable
205	Titration		stable
207	Transmissometer	Visual range is calculated by measuring the extinction coeffi...	stable
208	Transport modeling (model unspecified)		stable
209	Turbidity measurement		stable
210	Umkehr method		stable
211	Volumetric measurement		stable
212	Weighing type rain gauge (totalizer)		stable
213	Wet Chemical Methods [general]		stable
214	Wind sock (textile tube)		stable
215	Wind vane (solid blade)		stable
217	Aerodyne mass spectrometer (AMS)		stable
218	EUSAAR protocol		stable
219	Filter + beta attenuation (betameter, beta gauge)		stable
220	Filter + light attenuation (aethalometer)		stable
221	Mass Spectrometry (MS) [general]		stable
222	Monitor for AeRosols and GAses (MARGA)		stable
223	Particle induced x-ray emission (PIXE)		stable
224	Particle soot absorption photometry (PSAP)		stable
225	Thermo-optical analyzer (Sunset Labs)		stable
226	X-ray fluorescence (XRF)		stable
227	Aerodynamic particle sizing spectrometer (APS)		stable
228	Aerosol backscatter sonde		stable
229	Light scattering		stable
230	Nephelometry, integrating		stable
231	Cloud condensation nuclei (CCN) counter		stable
232	Condensation particle counter (CPC)		stable
233	Continuous gravimetry		stable
234	Differential mobility particle sizer (DMA, DMPS)		stable
235	Diffusion battery		stable
236	Electric mobility [general]		stable
237	Electrostatic classifier		stable
238	Multiangle absorption photometry (MAAP)		stable
239	Multistage impactor		stable
240	Optical particle counter (OPC)		stable
241	Scanning mobility particle sizer (SMPS)		stable
242	Twomey static thermal diffusion chamber		stable
244	Sun-tracking photometry		stable
245	Ceilometer		stable
246	Flexpart (dispersion modeling)		stable
247	Flextra (trajectory modeling)		stable
248	Hysplit (trajectory modeling)		stable
249	Lagranto (trajectory modeling)		stable
250	Thin film capacitance		stable
251	Chilled mirror		stable
252	Lithium chloride (LiCl)		stable
253	Hair hygrometer-hygrograph		stable
254	Hygrometer [general]		stable
255	IR absorption hygrometer		stable
256	Optical hygrometer		stable
257	UV fluorescence-based hygrometer (Lyman-α)	Detection of UV fluorescence signal emitted by the excited OH...	stable
258	Electrical aspiration (Frankenberger type)		stable
259	Mechanical aspiration		stable
260	(Ultra)sonic ranger		superseded
261	Gradiated pole		superseded
262	Snow pillow		superseded
263	Bimetallic actinograph		stable
264	Pyrheliometer (direct solar, broadband)		stable
265	Pyrgeometer (global, infrared)		stable
266	Pyranometer (global solar, broadband)		stable
267	Spectral pyranometer		stable
268	UV-vis spectrometry-radiometry		stable
269	Lidar for temperature observations	Light detection and ranging (Lidar) profiler for temperature ...	superseded
270	Tetrachloromercurate (TCM) absorption - CL		stable
271	Colorimetry (ANSA)		stable
272	Colorimetry (Griess)		stable
273	Colorimetry (indophenol, Bertholet)		stable
274	Colorimetry (mercury thiocyanate+iron alum)		stable
275	Colorimetry (NEDA)		stable
276	Colorimetry (Nessler, K2HgI4)		stable
277	Colorimetry (sodium salicylate method for nitrate)		stable
278	Colorimetry [general]		stable
279	Filter sampling (analytical method unspecified)		stable
280	Adsorption tube (charcoal) + elution + GC		stable
281	Filter sampling + combustion + IC		stable
282	Filter sampling + combustion + other		stable
283	Filter sampling + extraction + IC		stable
284	Filter sampling + extraction + other		stable
285	Filter sampling + gravimetry		stable
286	Impregnated filter		stable
287	Catalytic conversion 'Au' - CL		stable
288	Catalytic conversion 'Fe' - CL		stable
289	Catalytic conversion 'Mb' - CL		stable
290	Chemiluminescence (CL) [general]		stable
291	Photolytic conversion - CL		stable
292	Monitor for AeRosols and GAses (MARGA) Metrohm		stable
293	Filter sampling + photo multiplier tube (PMT)		stable
294	Fluorescence [general]		stable
295	UV fluorescence		stable
296	Vacuum UV fluorescence		stable
297	Gas Chromatography (GC) [general]		stable
298	GC-ECD		stable
299	GC-ECD-FID		stable
300	GC-ECD-MS		stable
301	GC-FID		stable
302	GC-HgO reduction-UV absorption		stable
303	GC-MS		stable
304	H2O2 conversion - IC		stable
305	Cavity ring-down spectroscopy (CRDS)		stable
306	Cavity-enhanced absorption spectroscopy (CEAS)		stable
307	Integrated cavity output spectroscopy (ICOS)		stable
308	Laser induced fluorescence (LIF)		stable
309	Laser photoacoustic spectroscopy (LPAS)		stable
310	Laser spectroscopy [general]		stable
311	Quantum cascade laser (QCL) spectroscopy		stable
312	Chemical ionization MS (CIMS) with matrix isolation		stable
313	Proton transfer reaction mass spectrometry (PTR-MS)		stable
314	IR spectrometry-radiometry [general]		stable
315	Light absorption photometry		stable
316	Long path absorption photometry (LOPAP)		stable
317	Non-dispersive IR (NDIR) absorption		stable
318	Non-dispersive UV (NDUV)		stable
319	UV absorption spectrometry-radiometry		stable
320	Integrated path differential absorption (IPDA) lidar	Light detection and ranging (lidar) with integrated path diff...	stable
321	Differential optical absorption (DOAS)		stable
322	Fourier-transform IR spectroscopy (FTIR)		stable
323	TCCON Fourier-transform IR spectroscopy (TCCON-FTIR)		stable
325	Magnetron		superseded
326	Klystron		superseded
327	Radiosonde with NAVAID		stable
328	Radiosonde with radar tracking		stable
329	Radiosonde with radiotheodolite tracking		stable
330	Radiosonde with composite method tracking		stable
331	Radiosonde (tracking unspecified)		stable
332	Pilot balloon with optical tracking)		stable
335	Differential absorption lidar (DIAL)	Light detection and ranging (lidar) with differential absorpt...	stable
336	Microwave radiometry		stable
338	Tunable diode lase spectroscopy (TDLS)	Tunable diode lase spectroscopy (TDLS)	stable
339	UV spectroradiometry		stable
340	Wet-bulb thermometer	A thermometer having a bulb that is kept moistened when humid...	stable
341	Backscatter lidar	Elastic backscatter light detection and ranging (lidar) typic...	stable
342	High spectral resolution (HSR) lidar	Light detection and ranging (lidar) with high spectral resolu...	stable
343	Polarized lidar	Light detection and ranging (lidar) capable of determining th...	stable
344	GC-CVAFS	Gas chromatography and detection by cold vapour atomic fluore...	stable
345	GC-TCD	Gas chromatography and detection by a thermal conductivity de...	stable
346	Electrostatic collection + alpha counting	Alpha counting after electrostatic collection of measurand.	stable
347	Tunable Infrared Laser Differential Absorption Spectroscopy (TILDAS)	Tunable Infrared Laser Differential Absorption Spectroscopy (...	stable
348	Radionuclide decay counting [general]	Determination of the counts measured per unit time as a resul...	stable
349	IR-GFC	Infrared absorption measurement based on the gas-filter corre...	stable
414	Fog collection	Collection of fog using a mesh or similar capturing device an...	stable
415	Campbell-Stokes burn method	Sunshine duration is determined by evaluating the burnt areas...	stable
416	Contrast-evaluating and scanning devices	Sunshine duration is determined by combining multi-sensor det...	stable
417	GC-CVAFS	Gas chromatography and detection by cold vapour atomic fluore...	stable
418	GC-TCD	Gas chromatography and detection by a thermal conductivity de...	stable
inapplicable	inapplicable	None of the codes in the table are applicable in the context ...	stable
unknown	unknown	The measurement/observing method is unknown.	stable