IEEE Geoscience and Remote Sensing Magazine - June 2015 - 27

ingesting, archiving and providing quality information to
the user communities. The concept implementation relies
on two major components: a software system [15] and a
Level 1 product Quality Control (QC)/ validation team.
This team runs the software system and performs activities with the objective of providing harmonized quality
information to the user communities.
Essentially the activities of the service are the management and analysis of quality information, the quality assessment of Copernicus Datasets together with validation
of the Earth Observation products included into these Datasets, and the harmonization of the quality information.
For information, the Copernicus Datasets are broken
into two main categories: the CORE Datasets and the ADDitional Datasets. The CORE Dataset is the fixed part of
the data offer, consisting in continuous data delivery from
systematic missions or generation of large predefined coverages. The ADDITIONAL Dataset is the on demand part of
the data offer. Both CORE and ADDITIONAL Datasets are
a collection of Earth Observation products delivered by the
various contributing missions.
A. QuAlity informAtion concept
The Copernicus world addresses different communities.
Despite them often having different requirements, there is
a consensus that the quality information is fundamental
for dimensioning the underlying EO service and ensuring
its correctness. However, the concept of quality information is extremely large and covers a variety of elements.
From the user perspective, it is important to have, principally, access to a synthetic view of the instrument and
product specifications (IPS). It was then expected that IPS
values might be associated with technical documents de-

scribing the methodology/results (background documentation), and an anomaly report (a posteriori report) illustrating deviations between the data provider specifications and
the results from QC. Also, it was expected that, in agreement with the data provider, the IPS would be regularly updated because of new findings while analyzing Copernicus
Datasets and calibration/validation products (synthesis report). An additional point discussed in IPS is the approach
for quality control and mission performance reporting. Indeed, ESA recommends the data provider to apply systematic QC on delivered products and also to regularly report
on mission performance.
The Table 1 shows how the quality information concept
has been implemented and in particular the perimeter of the
CQC. In order to manage the quality information and also
to allow its search by a user [15], a data model has been designed. Hence, all input quality information documents are
archived into a CQC package including basic metadata. The
metadata format is derived from [16] although it is not fully
compliant. The metadata format maintains strong relationship between quality information and its fields of applicability: Copernicus dataset, Product and Platform / Instrument.
The fields of applicability are also indicated in Table 1. The
instrument and product specification document is a focal
point since there is a strong relationship between the IPS and
all other document categories. The CQC software and team
ensure the configuration management of this documentation. All Copernicus services can request these documents
by using a standard user web interface, [15].
B. instrument And product specificAtion
The instrument and product specification is the most
important part of the system. Being a focal point of the

table 1. tHe cQc perimeter iS DefineD by tHe Different cateGorieS of Quality information to be Dealt WitH.
Quality information Document / fielD of applicability

content

Instrument Product Specification (IPS) /
Platform, Instrument

A specification table including the geometric, radiometric, spectral, orbit,
coverage and temporal characteristics of the mission.
It is delivered by the data provider during the integration of the mission
and it is regularly reviewed / updated by the CQC.

Background Documentation
(BgD) / Platform, Instrument

A technical report including the commissioning phase report, calibration /
validation reports, publication / article, description of the data processing
algorithms, the description of the product format. It is delivered by the
data provider and also by the CQC as a result of QC activities.

Mission Performance Report
(MPR) / Platform, Instrument

An operational report including status on mission / sensor performance. It
is delivered by the data provider on a cyclic basis.

Product Quality Report
(PQR) / Product

A quality control report including QC test results associated with each
product delivered to the user. The PQR are accessible from the EOLI SA
and the next generation of Earth Observation (ngEO) catalogue. It enables
Copernicus users to have access to product QC information when selecting / ordering products.

A-posteriori Report
(APR) / Product, Copernicus Dataset

An anomaly report including investigation on anomalies raised by the
Copernicus service. The report is issued by the CQC and reviewed, in some
cases, by the data provider.

Synthesis Report (SYR)
Copernicus Dataset

A technical report on completeness and fit for purpose of all delivered
Copernicus dataset.

june 2015

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Table of Contents for the Digital Edition of IEEE Geoscience and Remote Sensing Magazine - June 2015