#  Open Research Data, third (final) version, March 2018

**Project Name:** Gap Analysis for Integrated Atmospheric ECV Climate
Monitoring (GAIA-CLIM)

**Funder:** European Commission (Horizon 2020)

**Grant Title:** No 640276

#  1\. Project brief description

The Gap Analysis for Integrated Atmospheric ECV Climate Monitoring (GAIA-CLIM)
Project endeavoured to establish improved methods for the characterisation of
satellite-based Earth Observation (EO) data by surface-based and sub-orbital
measurement platforms for six of the GCOS atmospheric Essential Climate
Variables (ECVs), namely, Temperature, Water Vapour, Ozone, Carbon Dioxide,
Methane, and Aerosols. GAIA-CLIM added value by:

  * Objectively assessing and mapping existing measurement capabilities 

  

  * Improving traceability and uncertainty quantification on sub-orbital measurements; 

  

  * Quantifying co-location uncertainties between sub-orbital and satellite data; 

  

  * Using traceable measurements in data assimilation; and 

  

  * Providing co-location match-up data, metadata, and uncertainty estimates via a ‘virtual observatory’ facility. 

  

The novel approach of GAIA-CLIM was to demonstrate comprehensive, traceable,
EO Cal/Val for a number of metrologically mature ECVs, in the domains of
atmospheric state and composition, that will guarantee that products are
assessable and intelligible to third-party users.

Further details on GAIA-CLIM’s project outcomes can be found at  _www.gaia-
clim.eu_

#  2\. Outline of GAIA-CLIM’s policy for data management

GAIA-CLIM has been a member of the Open Data Pilot under H2020. The project
promoted the processing and sharing of data openly in support of project aims
of enhancing the long-term value of EO data for the scientific community. The
purpose of this Data Management Plan (DMP) is to document the collection and
use of data records that were managed within the GAIA-CLIM project. This third
and final version of the DMP, updated from previous versions D7.1 and D7.2,
reflects the final status of the project in relation to data produced and/or
collected. It provides a final agreed record of the data management policies
of GAIA-CLIM in respect of data dissemination.

This DMP ensured that:

  * There has been a coherent and evolving approach as to what, specifically, is required on management of data by the consortium throughout the lifetime of the project, and after its completion. 

  

  * Project findings are publicly available both during and after the project (including the virtual observatory, which will continue to be accessible on EUMETSAT servers after the end of the project). In addition, that they represent a lasting legacy to the contributing observing networks, leading to improvements in data traceability and comparability of EO measurement systems. 

  

  * Data preservation strategies are in place in support of long-term use of project outcomes. 

  

  * Data usage by GAIA-CLIM respects conditions of use, policy on access, and intellectual property rights of the primary data collectors, including authorship and acknowledgement that accurately reflects the contributions of those involved. 

  

It should be stressed that GAIA-CLIM constituted a rather particular case in
terms of data management as covered by the guidance pertaining to the
preparation of DMPs under the H2020 Pilot on Open Research Data. The project
did not directly collect primary data, i.e., make measurements for the sole
purpose of the project. Rather, it provided added value and additional
metadata to existing measurements (by optimizing the value of multiple sources
of primary data to enable traceable characterization of EO data) taken by both
consortium members under separate funding support and by third party
institutions. Therefore, and in line with the project objectives, as used in
this document, the term ‘project data’ refers to metadata and / or value-added
products, i.e. secondary data products arising from primary data created,
hosted, and managed by existing networks and stations, in order to improve
global capabilities to use non-satellite data to characterise space-borne
satellite measurement systems.

In this context, it is important to stress that GAIA-CLIM has retained only
that primary data used in its mission, which solely constitutes a small subset
of the primary data made available by the contributing observing networks. It
was never the intention of GAIA-CLIM to create or curate a comprehensive
archive from underlying primary observational networks, nor would it have been
practical to do so. Contributing networks retain primary Intellectual Property
Rights (IPR) and may well, in future, revise their data, data formats,
metadata etc. We note in particular that the C3S 311a Lot 3 activity  1  ,
instigated in 2017 (and led by GAIA-CLIM participants), constitutes an
operational service for accessing the baseline and reference in-situ data
holdings. This is a more appropriate mechanism to address the issue, providing
a sustainable long-term resource for multiple use cases.

Sharing of value added products derived from GAIA-CLIM is important to the
long-term study of EO sensor performance, validation of satellite-derived data
products, and to maximize their value in climate applications. In this regard,
this DMP focusses primarily upon supporting the scientific findings of the
project, which has been actively working to create appropriate linkages, and
maximize the availability and utility of the data and tools produced after the
project. The release of the data and associated products into the public
domain has been the _de facto_ policy, ensuring usability and longterm
availability of data to scientific and public audiences alike. Collaboration
with internal and external project partners will remain ongoing to ensure this
takes place on a best endeavours-basis post-project cessation.

The main way of actually serving data from the GAIA-CLIM project is through
its ‘virtual observatory’ tool  2  , developed and hosted by TUT and EUMETSAT.
The virtual observatory is intended to provide the user with access to both
metadata and observational data from different ground-based reference networks
with co-located satellite data. GAIA-CLIM has used measurements of
metrologically “reference-quality” (from GRUAN and NDACC networks) that are
traceable and have well quantified uncertainty estimates and measurements
(from AERONET), for which no sufficient evidence has yet been provided to
assess the reference-quality status, but which are close to that status. A
full listing of contributing observations is available at the end of this
document under Annex 2. Importantly, GAIA-CLIM only made use of those primary
observations to which no academic restrictions to use, reuse, and re-
distribution currently apply. The providers of primary data from these
networks have thereby either implicitly or explicitly agreed to release that
portion of their data which we have utilised according to this DMP. Similarly,
GAIA-CLIM has only used satellite data available for re-use and
redistribution. Furthermore, re-analysis and Numerical Weather Prediction
(NWP) data are also part of the virtual observatory. Such data arose from
within the consortium (ECMWF and MO partners under WP4) without restriction.
However, GAIA-CLIM work in many cases built upon pre-existing capabilities of
the partners. In a restricted subset of these cases, IPR restrictions relate
to these background materials as articulated in the Consortium Agreement (cf.
Annex 1). A list of co-located datasets available in the virtual observatory
is given in Annex 3.

The virtual observatory data policy is made explicit and is in compliance with
the H2020 Pilot on Open Research Data (s. next section) and this DMP.

Project parts that dealt with enhancing existing primary data streams were:

  * Preparation and assessment of reference-quality non-satellite data (including in global assimilation systems) and characterisation of key satellite datasets: 

    1. Assessment of several new satellite missions, using data assimilation of reference-quality non-satellite measurements, targeting temperature and humidity (under work package 4). 

  

    2. Development of infrastructure to deliver quantified uncertainties for reference-data colocations with satellite measurements (under work packages 3 and 5). 

  

    3. Development of capabilities for preparation, monitoring, analysis, and evaluation of reference-quality data (under work packages 2 and 5). 

  

    4. Development of a general methodology for using reference-quality non-satellite data for the characterisation of EO data (under work packages 4 and 5). 

  
  

  

  * Creation and population of a virtual observatory: 

    1. Creation of a collocation database between EO measures and reference-quality measurements. 

  

    2. Adoption of ISO/WIGOS and ESA-CCI standards for observational metadata in the virtual observatory. 

  

    3. Preparation of data to enable comparisons, including relevant uncertainty information and metadata for users to understand and make appropriate use of the data for various applications. 

  

    4. Creation of data interrogation and visualization tools for both non-satellite and satellite observing capabilities, building upon existing European and global infrastructure capabilities offered by partners and in-kind collaborators. 

  

    5. Planning for the potential transition of the resulting virtual observatory from research to operational status in support of the Copernicus Climate Change Service (C3S) and Copernicus Atmospheric Monitoring Service (CAMS). 

  
  

  

#  3\. Pilot on Open Research Data

GAIA-CLIM participated in the H2020 Pilot on Open Research Data. Knowledge
generated during the project has been shared openly. Any milestones,
deliverables, or technical documents produced, which were deemed public in the
Grant Agreement, have all been published online and made discoverable. Peer-
reviewed publications have all been submitted to journals that are either open
access or allow the authors to pay for the articles to be made open access
(for such instances, the additional charges have been paid).

#  4\. Dissemination and Exploitation of Results

In order to maximize the benefit and usability of project findings, GAIA-CLIM
incorporated a strong focus on user interaction throughout the life cycle of
the project. The virtual observatory, as a key outcome of the project, is the
primary means of dissemination of data and associated project findings through
which end-users are able to access, visualize, and utilize the outputs of the
project. The virtual observatory built upon and extended a number of existing
facilities operated by project partners, which already undertook subsets of
the desired functionality, specifically:

  * the Network of Remote Sensing Ground-Based Observations in support of the Copernicus Atmospheric Service (NORS); 

  

  * the Cloud-Aerosol-Water-Radiation Interactions (ICARE) Project; 

  

  * the US National Oceanic and Atmospheric Administration (NOAA) Products Validation System (NPROVS). 

  

The resulting virtual observatory facility is entirely open and available to
use for any application area. All downloaded data are provided in NetCDF-4
format and use the Climate and Forecast (CF) metadata convention. Significant
efforts have been made to build an interface that is easy to use and which
makes data discovery, visualization, and analysis user-friendly. The virtual
observatory work package included a specific task dedicated to documenting the
steps required to transition this facility from a research to an operational
framework with a view to constituting a long-term infrastructure (see
deliverable D5.8 Transition roadmap for the virtual observatory  3  ).

The GAIA-CLIM website  4  represents the public interface of the project and
shall remain available for at least five years after the end of GAIA-CLIM (on
a best endeavours maintenance basis from NERSC). It provides an overview of
the main results, activities by work package, as well as an open portal to
disseminate information on project outcomes such as publications, peer-
reviewed journal articles, and project deliverables. This particularly
includes access to:

  * The  _Library of (1) smoothing/sampling error estimates for key atmospheric composition_ _measurement systems, and (2) smoothing/sampling error estimates for key data comparisons_ , 

  

  * The  _Product Traceability and Uncertainty_ (PTU) documents developed by WP2. 

  

  * The full  _list of gaps_ i  n knowledge and observing capability identified within the scope of GAIACLIM; 

  

  * The  _virtual observatory_ ,  and 

  

  * The ‘  _GRUAN Processor_ ’  tool. 

  

#  5\. Preservation of value added data products

The value-added tools and data products GAIA-CLIM has retained and made
available consist of:

  * Metadata collected under work package 1 relating to networks and their measurement maturity. This included: 

  

o Station location metadata to ISO standard 19115; o Measurement system
metadata; o Visualisation capabilities; o 3D-tool design for the visualisation
of existing measurements online; o Measurement maturity assessment metadata; o
Observational metadata following WIGOS and ESA-CCI standards.

  * Selected primary data that meets co-location criteria and is deemed reference quality or almost reference quality from underlying networks. (work package 2) 

  

  * Co-location uncertainty information arising from a variety of approaches, including statistically based and dynamically based estimation (work packages WP3 and WP4). 

  

  * The “GRUAN Processor” tools to convert from geophysical to Top of the Atmosphere (TOA) radiance (WP4). 

  

  * Capabilities to visualize, subset, and analyse the co-location database (work package WP5). 

  

Most of the above products and capabilities have been hosted and preserved at
th  e _www.gaia-clim.eu_ domain. Those tools and capabilities preserved
elsewhere are described in subsequent sub-sections.

Were follow-on support available, then new data and services may be able to be
appended and the facilities made operational. These new data and capabilities
would be subject to the data policies of the provider and funder at that time.
GAIA-CLIM shall undertake solely to preserve and make available the data and
functionalities created during the project lifetime.

###  5.1 Virtual observatory

The virtual observatory constitutes the primary means of dissemination of
project results. The virtual observatory facility is entirely open and
available to use for any application area. Data versioning, source locations,
and any DOIs from the primary data sources are retained. Significant efforts
were undertaken to collaborate with existing European and international
programs with similar aims in order to produce a facility which makes data
discovery, visualization, and analysis easy and useful for the end users,
while optimizing the use of reference data. The objective was to develop an
interface that uses software tools to deliver products in standard formats,
such as NetCDF that are compliant with CF conventions. Such formats are self-
describing and provide a definitive description of what the data in each
variable represents, as well as the spatial and temporal properties of the
data. This enables users of data from different sources to decide which
quantities are comparable, and facilitates building applications with powerful
extraction and display capabilities. In turn, this may support the relevance
and sustainability of the facility, or aspects thereof, into the future, as
well as effective data preservation.

The final data products will be kept beyond the lifetime of the project
through the virtual observatory, which shall be hosted by EUMETSAT. It is
important to stress that the virtual observatory is solely a demonstrator
project and therefore the GAIA-CLIM data, documentation, and functionalities
will be retained in “frozen” mode in the state they existed in at the end of
the project with the aim of becoming further developed and integrated into the
emerging Copernicus or any other service. If continued in this way, data and
software distribution policies of the respective service will be applied in
the long-term.

The virtual observatory has been designed and developed as a traditional
client-server application. Visible to the user is the graphical user interface
(GUI) that allows the user to interact with the components of the virtual
observatory. The GUI is used to send queries to retrieve data that result in
graphical displays. The data themselves are stored in a non-relational
database that holds all the data including the uncertainties of the
measurements and the co-locations available in the virtual observatory. The
non-relational data base is very versatile, allowing easy addition of new data
of various types to the virtual observatory and makes extensions in the future
relatively simple, should the virtual observatory be further developed and
made operational.

###  5.2 Metadata discovery tool

The metadata discovery and visualization tool is planned to be maintained by
CNR over long-term, including annual updates of the metadata and the GUI. The
discovery and observational metadata was realised in PostgreSQL and then
linked to a MongoDB via GeoServer platform, all of which are open source. The
3D tool uses the Cesium JavaScript library, which is distributed under the
Apache 2.0 license agreement. To remain consistent with the conditions of use
in our 3D tool, the Cesium logo and a link to its website are present. The
source code of the 3D tool itself is openly available on Github  5  ,
including documentation  6  .

###  5.3 Library of smoothing/sampling uncertainties

Research was undertaken within GAIA-CLIM to improve quantification of the co-
location mismatch uncertainties. Several methods have been developed for - and
applied to - the quantification of smoothing and sampling issues in a range of
atmospheric ground-based measurement techniques, and to estimate the
uncertainties that need to be taken into account when comparing non-perfectly
co-located ground-based and satellite measurements with different spatio-
temporal smoothing and sampling properties. The resulting software and Look-up
tables that constitute input to the virtual observatory have been documented
and shared openly without restriction. The actual guiding material and data
files are hosted by BIRA and available for download by anonymous/guest ftp at:
_ftp://ftp-ae.oma.be/dist/GAIA-CLIM/D3_6/_

###  5.4 GRUAN processor

A stand-alone ‘GRUAN Processor’ module has been developed based on a core
radiative transfer modelling capability built around two existing open-source
software packages (EUMETSAT’s NWP SAF  7  RTTOV fast radiative transfer model
and Radiance Simulator). This software, referred to as the GRUAN Processor,
enables the comparison of collocated geophysical fields and simulated
brightness temperature between radiosonde and model fields.

The Processor will allow improved NWP-based calibration, recalibration, and
validation of satellite instruments thanks to robust channel-by-channel
uncertainty estimates. In addition, it is expected to serve as a long-term,
semi-automatic, monitoring tool for the Met Office NWP global model. The
integration and automation of the Processor in the Met Office system is
expected to take place during the fiscal year 2018/2019. It is to the
discretion of ECMWF to use their copy of the Processor (installed and used
within the scope of the GAIA-CLIM project), and/or its future versions, as an
additional monitoring tool in their system.

This work is in line with the Copernicus CAMS and C3S streams and has the
potential to become an operational Copernicus service with data and graphic-
based monitoring available from the Copernicus portal. The Processor post-
processed outputs are publicly available on a demonstrator web-page  7  hosted
by NWP SAF.

#  6\. Primary source datasets used within GAIA-CLIM

The final contributing networks to the virtual observatory were as follows:

  1. GRUAN, 

  

  2. NDACC, and 

  

  3. AERONET. 

  

  

Further details on these networks, their governance, and their data policies
are given in Annex 2. A list of co-located datasets available in the virtual
observatory is given in Annex 3. As primary data collectors, these networks
have assessed data quality, integrity, originality, and content prior to
publishing. Whilst GAIA-CLIM activities under work package 2 lead to changes
in how a subset of the data are processed by the underlying networks, GAIA-
CLIM was a user, not at a provider, of these primary data products.

As described previously, GAIA-CLIM has respected the data policies and
practices of the data originators/custodians, and the documentation herein
should not be taken to imply advocacy for changing their existing policies.
Rather, it is important to note that GAIA-CLIM activities and this DMP work
alongside and document existing practices that pertain to the source data.
Where networks have data policies that place restrictions on near-real-time
use, GAIA-CLIM has only used the open delayedmode data.

#  7\. Summary

This Data Management Plan presents the data management policy that has been
used by the GAIACLIM partners in their collection and use of data records
during the lifespan of the project. This third and final DMP version has
evolved to reflect the conclusion of the project. Since there was no primary
data produced under the GAIA-CLIM project, the data management policy relates
to metadata and added-value products produced in GAIA-CLIM for existing and
future measurements. This is in keeping with the over-arching objectives of
GAIA-CLIM to provide the necessary methodologies for the characterization of
satellite-based EO data using surface and sub-orbital measurements.