KMI - Measuring ozone

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main-header__mobile-btn js-mobile-nav-button"> <span class="main-header__mobile-btn__text">menu</span> <span class="main-header__mobile-btn__icon"> <span></span> <span></span> <span></span> <span></span> </span> </button> </div> </header> <div class="main-content-wrapper mobile-nav__content"> <header class="subsite-page-title-wrapper"> <div class="container"> <h1 class="subsite-page-title"> <span class="subsite-page__title__inner"> Ozone, UV and Aerosol studies </span> </h1> </div> </header> <div class="container"> <main role="main" class="main-content"> <div class="container"> <div class="row standard-content"> <div class="col-md-3"> <div class="box"> <nav class="sidebar-nav"> <h3 class="sidebar-nav__title"> Research </h3> <ul class="sidebar-nav__list"> <li id="subnav-5455" class="sidebar-nav__list__item sidebar-nav__list__item--active sidebar-nav__list__item--open sidebar-nav__list__item--sublist"> <a href="/research-themes/ozone"> Ozone </a> <ul class="sidebar-nav__list__item__sublist"> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/ozone/introduction">Ozone in the atmosphere</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/ozone/the-ozone-hole">The ozone hole</a> </li> <li class="sidebar-nav__list__item__sublist__item sidebar-nav__list__item__sublist__item--active"> <a href="/research-themes/ozone/measuringozone">Measuring ozone</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/ozone/instrumental-research">Ozone measurements at Uccle</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/ozone/longtermtrendsuccle">Long-term ozone trends at Uccle</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/ozone/50-years-of-ozone-measurements-at-uccle">50 years of ozonesonde measurements at Uccle</a> </li> </ul> </li> <li id="subnav-5571" class="sidebar-nav__list__item sidebar-nav__list__item--sublist"> <a href="/research-themes/uv"> Ultraviolet (UV) radiation </a> <ul class="sidebar-nav__list__item__sublist"> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/uv/what-is-the-uv-index">What is the UV index?</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/uv/todays-uv-index-at-uccle">Today's UV index at Uccle</a> </li> </ul> </li> <li id="subnav-5447" class="sidebar-nav__list__item sidebar-nav__list__item--sublist"> <a href="/research-themes/aerosols"> Aerosols </a> <ul class="sidebar-nav__list__item__sublist"> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/aerosols/what-are-the-effects-of-aerosols">Why investigate aerosol particles?</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/aerosols/measurements-of-atmospheric-aerosol-particles">Measurements of atmospheric aerosol particles</a> </li> </ul> </li> <li id="subnav-5574" class="sidebar-nav__list__item sidebar-nav__list__item--sublist"> <a href="/research-themes/water-vapour"> Water vapour </a> <ul class="sidebar-nav__list__item__sublist"> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/water-vapour/total-column-water-vapour">Total column water vapour</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/water-vapour/iwv-intercomparisons">IWV intercomparisons</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/water-vapour/fog">Radiation fog</a> </li> </ul> </li> <li id="subnav-5575" class="sidebar-nav__list__item sidebar-nav__list__item--sublist"> <a href="/research-themes/atmospheric-modelling"> Atmospheric modelling </a> <ul class="sidebar-nav__list__item__sublist"> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/atmospheric-modelling/biogenic-modelling">Airborne allergenic pollen modelling</a> </li> </ul> </li> <li id="subnav-5739" class="sidebar-nav__list__item "> <a href="/research-themes/atmospheric-profiling"> Atmospheric profiling </a> </li> </ul> </nav> </div> </div> <div class="col-md-9 sub-page__content"> <div class="box box--content"> <h2 class="box__title">Measuring ozone</h2> <div class="introtext-pp text--intro"> <p>The abundance of ozone in the atmosphere is measured by a variety of techniques that make use of ozone’s unique optical and chemical properties. There are two principal categories of measurement techniques: local and remote. Both ozone measurement techniques have been essential in monitoring changes in the ozone layer and in developing our understanding of the processes that control ozone abundances.</p> </div> <figure class="image-pp"> <img srcset="https://ozone.meteo.be/media/cache/image_small_png/uploads/media/65b7bfd564b4f/q4-1-2022.png 400w, https://ozone.meteo.be/media/cache/image_medium_png/uploads/media/65b7bfd564b4f/q4-1-2022.png 600w, https://ozone.meteo.be/media/cache/image_big_png/uploads/media/65b7bfd564b4f/q4-1-2022.png 1200w, https://ozone.meteo.be/media/cache/image_huge_png/uploads/media/65b7bfd564b4f/q4-1-2022.png 2251w" sizes="100vw" style="width:2251px" alt="measuring ozone" loading="lazy" decoding="async"/> <noscript> <img src="https://ozone.meteo.be/media/cache/image_big_png/uploads/media/65b7bfd564b4f/q4-1-2022.png" alt="measuring ozone" loading="lazy" decoding="async"/> </noscript> <div class="container"> <figcaption> <p>Ozone is measured throughout the atmosphere with instruments on the ground, aircraft, high-altitude balloons, and satellites. Some instruments measure ozone locally in sampled air and others measure ozone remotely a considerable distance away from the instrument. Instruments use optical techniques with either the Sun (direct, reflected, or scattered radiation) or lasers (green lines) as light sources; detect the thermal emissions from ozone and other atmospheric molecules (not shown); or use chemical reactions that are unique to ozone (ozonesonde). Ref: Ross J. Salawitch (Lead Author) et al., "Twenty Questions and Answers About the Ozone Layer: 2022 Update, Scientific Assessment of Ozone Depletion: 2022", 75 pp., World Meteorological Organization, Geneva, Switzerland, 2023.</p> </figcaption> </div> </figure> <h3 id="local-measurements"> Local measurements </h3> <div class="text-pp"> <p>Local measurements of the atmospheric abundance of ozone are those that require air to be drawn directly into an instrument. Once inside an instrument’s detection chamber, the amount of ozone is determined by <strong>measuring the absorption of ultraviolet (UV) light</strong> or by the <strong>electrical current or light produced in a chemical reaction</strong> involving ozone. The last approach is used in “<a href="/instruments-and-observation-techniques/ozonesondes" target="_blank">ozonesondes</a>”, i.e. lightweight, ozone-measuring modules suitable for launching on small balloons. Local ozone-measuring instruments using optical schemes are also used on commercial aircraft to measure the distribution of ozone in the troposphere (e.g. <a href="https://www.iagos.org/" target="_blank">IAGOS</a>).</p> </div> <h3 id="remote-measurements"> Remote measurements </h3> <div class="text-pp"> <p>Remote measurements of total ozone amounts and the altitude distributions of ozone are obtained by detecting ozone at large distances from the instrument. Ground-based <a href="/instruments-and-observation-techniques/spectrophotometers">spectrophotometers</a> measure the total ozone amount by detecting small changes in the amount of the Sun’s UV radiation that reaches the Earth’s surface. But also several satellite instruments use the <strong>absorption of solar UV radiation by the atmosphere</strong> or the <strong>absorption of sunlight scattered from the surface of Earth</strong> to measure ozone on a daily basis, and over nearly the entire globe. Other instruments measure ozone using its <strong>absorption of infrared or visible radiation or its emission of microwave or infrared radiation</strong> at different altitudes in the atmosphere, thereby obtaining information on the vertical distribution of ozone.</p> </div> <p class="link-pp "> <a href="/research-themes/ozone/instrumental-research" > The ozone measurements at Uccle </a> </p> <p class="totop-pp"><a href="#">Top</a></p> </div> </div> <div class="col-md-12 visible-xs visible-sm"> <h2 class="subpage__content__read-more"> Read more </h2> <div class="box"> <nav class="sidebar-nav"> <h3 class="sidebar-nav__title"> Research </h3> <ul class="sidebar-nav__list"> <li id="subnav-54551" class="sidebar-nav__list__item sidebar-nav__list__item--active sidebar-nav__list__item--open sidebar-nav__list__item--sublist"> <a href="/research-themes/ozone"> Ozone </a> <ul class="sidebar-nav__list__item__sublist"> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/ozone/introduction">Ozone in the atmosphere</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/ozone/the-ozone-hole">The ozone hole</a> </li> <li class="sidebar-nav__list__item__sublist__item sidebar-nav__list__item__sublist__item--active"> <a href="/research-themes/ozone/measuringozone">Measuring ozone</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/ozone/instrumental-research">Ozone measurements at Uccle</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/ozone/longtermtrendsuccle">Long-term ozone trends at Uccle</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/ozone/50-years-of-ozone-measurements-at-uccle">50 years of ozonesonde measurements at Uccle</a> </li> </ul> </li> <li id="subnav-55711" class="sidebar-nav__list__item sidebar-nav__list__item--sublist"> <a href="/research-themes/uv"> Ultraviolet (UV) radiation </a> <ul class="sidebar-nav__list__item__sublist"> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/uv/what-is-the-uv-index">What is the UV index?</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/uv/todays-uv-index-at-uccle">Today's UV index at Uccle</a> </li> </ul> </li> <li id="subnav-54471" class="sidebar-nav__list__item sidebar-nav__list__item--sublist"> <a href="/research-themes/aerosols"> Aerosols </a> <ul class="sidebar-nav__list__item__sublist"> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/aerosols/what-are-the-effects-of-aerosols">Why investigate aerosol particles?</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/aerosols/measurements-of-atmospheric-aerosol-particles">Measurements of atmospheric aerosol particles</a> </li> </ul> </li> <li id="subnav-55741" class="sidebar-nav__list__item sidebar-nav__list__item--sublist"> <a href="/research-themes/water-vapour"> Water vapour </a> <ul class="sidebar-nav__list__item__sublist"> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/water-vapour/total-column-water-vapour">Total column water vapour</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/water-vapour/iwv-intercomparisons">IWV intercomparisons</a> </li> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/water-vapour/fog">Radiation fog</a> </li> </ul> </li> <li id="subnav-55751" class="sidebar-nav__list__item sidebar-nav__list__item--sublist"> <a href="/research-themes/atmospheric-modelling"> Atmospheric modelling </a> <ul class="sidebar-nav__list__item__sublist"> <li class="sidebar-nav__list__item__sublist__item "> <a href="/research-themes/atmospheric-modelling/biogenic-modelling">Airborne allergenic pollen modelling</a> </li> </ul> </li> <li id="subnav-57391" class="sidebar-nav__list__item "> <a 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