Near-real time ozone forecasting made possible by Envisat

Stratospheric data supplied by Envisat are the basis for a near-real time global ozone forecasting service now available online.

Up in the stratosphere about 25 km above our heads is the ozone layer. Stratospheric ozone absorbs up to 98% of the Sun’s harmful ultraviolet light – making the difference between a suntan and sunburn, and safeguarding all life on Earth. But chemical activity in the stratosphere ultimately due to the presence of manmade gases such as chlorofluorocarbons (CFCs) can thin the ozone layer.

The Brussels-based Belgian Institute for Space Aeronomy (BIRA-IASB from its initials in Flemish and French) has developed a service called the Belgian Assimilation System of Chemical Observations from Envisat (BASCOE) that maps and forecasts not only the concentration of ozone in the stratosphere but also 56 other chemical species, including those responsible for ozone depletion.

BASCOE relies on an instrument aboard Envisat called the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS). It works day and night to measure infrared emissions from the Earth’s ’limb’ – the narrow band of atmosphere between the planetary surface and empty space. Emissions along certain wavelengths work like signatures, indicating the presence of specific atmospheric chemicals.

MIPAS has the capability to measure up to 30 trace gas species, but for the time being only a subset of them is provided by the ESA ground segment operationally to the user community. The others whose concentrations are forecast by BASCOE have their presence calculated indirectly, by assimilating MIPAS level 2 products into a complex computer model of stratospheric chemistry processes developed by BIRA-IASB. The resultant analyses are available within a day.

“The stratosphere is one of the best-understood areas of atmospheric chemistry, a fact which makes the BASCOE model possible,” explained Dominique Fonteyn of BIRA-IASB. “In fact this model predates the launch of Envisat, and was originally intended simply as a summary of our existing understanding of stratospheric chemistry. But the large amount of work that went into it – some 50,000 lines of code – made us look at using it in other ways, and assimilating Envisat data into it for operational use.

“The aim was to reduce the usual time delay between satellite observation and data use, in the same way weather forecasting does. As well as chemical interactions, the model also includes weather data provided by the European Centre for Medium Range Weather Forecasts, because polar stratospheric clouds transported by winds play a major role in the process of ozone destruction.”

Users of the service – available at http://bascoe.oma.be – can obtain forecasts of global ozone levels for the week ahead as well as maps of nitric acid trihydrate (NAT) and active chlorine (ClOx), both implicated in ozone thinning.

The intention to use the MIPAS data to ’fine-tune’ the model in future for increased accuracy, along with assimilating data from other Envisat instruments such as GOMOS (Global Ozone Monitoring by Occultation of Stars) and SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Cartography) once they become available.

Media Contact

Claus Zehner European Space Agency

All news from this category: Earth Sciences

Earth Sciences (also referred to as Geosciences), which deals with basic issues surrounding our planet, plays a vital role in the area of energy and raw materials supply.

Earth Sciences comprises subjects such as geology, geography, geological informatics, paleontology, mineralogy, petrography, crystallography, geophysics, geodesy, glaciology, cartography, photogrammetry, meteorology and seismology, early-warning systems, earthquake research and polar research.

Back to the Homepage

Comments (0)

Write comment

Latest posts

Seawater as an electrical cable !?

Wireless power transfers in the ocean For drones that can be stationed underwater for the adoption of ICT in mariculture. Associate professor Masaya Tamura, Kousuke Murai (who has completed the…

Rare quadruple-helix DNA found in living human cells with glowing probes

New probes allow scientists to see four-stranded DNA interacting with molecules inside living human cells, unravelling its role in cellular processes. DNA usually forms the classic double helix shape of…

A rift in the retina may help repair the optic nerve

In experiments in mouse tissues and human cells, Johns Hopkins Medicine researchers say they have found that removing a membrane that lines the back of the eye may improve the…

Partners & Sponsors

By continuing to use the site, you agree to the use of cookies. more information

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.

Close