create ozone sonde measurements documentation

docs/b-data-atmosphere/b5-ozone-measurements-profiles.md

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-# Ozone measurements – Profiles (O3 radio soundings, SOMORA)
+# Ozone measurements – Profiles (O3 soundings, SOMORA MWR, Dobson and Brewer Umkehr)
+MeteoSwiss launches balloon-borne ozone sondes three times a week (12:00 UTC) from the sounding station in Payerne (PAY, 46.81°N, 6.94°E). The timeseries is one of the world's longest continuous vertical ozone profile records dating back to 1968. 
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+The electrochemical concentration cell (ECC) ozone sonde from [EN-SCI](https://www.en-sci.com/ecc-ozonesonde/) measure the current produced by the red-ox reaction of ozone in a potassium iodide solution (0.5% KI in bromide buffer). The ozone partial pressure (in mPa) is calculated from the cell current, the air temperature, the pump flow rate and the conversion efficiency. A background current is characterized during the Standard Operation Procedure ([SOP](https://www.fz-juelich.de/en/ice/ice-3/scientific-infrastructure/asopos)) and subtracted from the in-flight measured current. ECC sondes are the international standard for vertical ozone profiling and provide measurements from the surface to ~30-35 km altitude with ~5% accuracy.
+
+The ozone profiles measurement are essential for climate research and assessment of [ozone recovery](https://portal-cdn.scnat.ch/asset/ada969fa-0e8b-584a-bb54-09351504e952/Scientific-Assessment-of-Ozone-Depletion-2022-Executive-Summary%20%281%29.pdf?b=92b1b4c2-dd69-50a5-908e-bce08e9ea5d7&v=aa61c90c-a394-5c1c-8845-6aa45bdf8a4c_0&s=I05nHAAbyzH0_iDk3-m_2uQOVLU5_CDoK9IcXBv4YJ3deYA3pdSbRhu-xOkrgXH5Wc3qQ5MXQnRiGOcC7qyKahhCM-e58UY0-ZpAQyK5O2j6ZEgztqg7Cz2z0YE3-kz0rynqLl-ZgWJrnHME5qPuFc2xpsoNZAclVrlGO7wTOn4). The data are saved daily in the MeteoSwiss database, uploaded daily to the [NILU EVDC database](), uploaded monthly to the [NDACC DHF](https://www-air.larc.nasa.gov/missions/ndacc/data.html?station=payerne/ames/o3sonde/) and to the WMO [WOUDC](https://woudc.org/en/data/data-search-and-download) database.
 
 :::warning