Infrared and Visible Optical Sensors

Discussion forum (Wiki) for EO Cal/Val topics

nigelfox — Tue, 22 May 2007 16:03:55 +0000

A new discussion forum has been established to discuss key topics of relevance to the Earth Observation Calibration and Validation community with an emphasis on “Optical sensors and associated systems and infrastructure” http://www.technology-roadmaps.org/ivos/doku.php The current driver for these topics is the requirement (DA-06-02) established by GEOSS to: Develop GEO data quality assurance strategy, beginning with space-based observations and evaluating expansion to in-situ observations.

Please contribute to the discussion and encourage your colleagues to do so as well. If appropriate please feel free to establish new topics of discussion on new pages.

Upcoming Events

Diabound — Mon, 12 Mar 2007 14:39:59 +0000

Registration is now available for CEOS WGCV IVOS 18 (June 11, 2007) at NPL, London, and also for CEOS WGCV plenary 27 (June 12-15, 2007) at NPL, London.

Click here for more information.

Results of: Survey to identify priority requirements for improved data quality for the success of GMES and GEOSS

Diabound — Mon, 12 Mar 2007 11:23:44 +0000

The National Physical Laboratory, the UK national standards laboratory, is leading a study on behalf of ESA to identify and prioritise the requirements for improved data quality to satisfy the current and future needs of the European Earth Observation community, in the GMES context. The results are of course likely to be of interest to the international EO community as a whole in relation to the implementation of the objectives of GEO.

As part of this study a short web based survey was carried out to collect views from the EO community regarding the need for any improvement to data product quality not only in terms of its inherent property but also in how this is ascribed to a delivered product.

Although for some applications it will be essential that there is some form of “certification” of data product quality, it is critical that any new system must be “fit for purpose” and not add time, cost or complexity unless clear benefits are identified.

In order to consult as widely as possible all stakeholders within the EO community were encouraged to make their voice heard through the completion of a short web survey. The results of this survey are now available for review by the community in the associated document.

If you have any comments on the survey or its results please do not hesitate to contact me via the following methods.

More information about the survey is available here

CEOS recommended solar irradiance spectrum for use in Earth Observation applications

hpegrum — Fri, 15 Dec 2006 14:11:34 +0000

Use of exo-atmospheric solar spectral irradiance (200 to 2400 nm)

There are many applications in optical based Earth Observation applications that the use of an exo-atmospheric solar irradiance spectrum is required, and in many cases is embedded as a default, although changeable in many models, particularly radiative transfer codes. However over the years different data sets and models have been derived and subsequently used by different research groups. This has on some occasions led to confusion within the community and sometimes the unfounded cause for debate on observed biases in resultant data products.

As an attempt to minimise this problem CEOS WGCV (endorsed by CEOS plenary 17) has recommended that where possible, use is made of a “standard spectrum” at the highest possible resolution At present the international consensus is that this standard spectrum is a composite published by Thuiller et al and summarised in an Excel spreadsheet available via the following link or on the IVOS private workspace. Standard Spectrum Spreadsheet

G. Thuillier; M. Hersé; D. Labs; T. Foujols; W. Peetermans; D.Gillotay; P.C. Simon; H. Mandel Solar Physics 214(1): 1-22 (2003) http://www.springerlink.com/content/qk6574304g27m272/

However, it is considered essential that in all relevant publications the exact spectrum used should be reported, together with any band integration used, to allow proper comparisons of results to be undertaken. It should therefore be considered when peer reviewing future publications.

Welcome to IVOS

nanodave — Mon, 13 Nov 2006 17:30:24 +0000

Welcome to the IVOS website. Here you will find information and news from the working group, including details of our projects. There are also some useful links to information of interest to the Earth Observation community including the latest news from ESA and NASA.