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Cimel Update

The FSF Cimel sun photometer has joined the AERONET sun photometer network. It was upgraded and calibrated by NASA Goddard Space & Flight Centre in October 2005, before being relocated to the Chilbolton Observatory. The decision was made following a consultation process with our users and then put forward for discussion at our Bi-annual Steering Committee Meeting in May 2005.The FSF Cimel will be one of the first sun photometers in the UK to become part of the AERONET Program. The Cimel will no longer be available for loan to FSF users. However, it will remain the property of FSF, and be stationed and supported by CCLRC at, the Chilbolton Observatory, Hampshire.

If you wish to see the specifications of this instrument then click here


The AERONET (AErosol RObotic NETwork) program is made up of 236 Cimel sun photometers world-wide providing access to continuous, globally distributed observations of spectral aerosol optical depths, inversion products, and precipitable water in geographically diverse aerosol regimes. The data is analysed by NASA who then assess aerosol optical properties and validate satellite retrievals of aerosol optical properties.

Locations details and contact information for the Cimel sun photometer on the Chilbolton site are available through the AERONET site information page.

Getting AERONET data

Level 1.0 and 1.5 direct sun, AOT, Almucantars and Principle Plane data sets for the FSF Chilbolton sun photometer are available from the AERONET site for dates starting from October 2005. A complete listing of sites and data sets from all the other AERONET instruments world-wide can be downloaded free of charge from the AERONET website by following this link, click on the 'Download tool' under 'Data Access.'