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The METAFOR project: providing community metadata standards for climate models, simulations and CMIP5
No full textThe results of climate models are now of more than purely academic interest: governments and the private sector
also have a need to discover the results in order to prepare for and mitigate against the potentially severe impacts
of global climate change. Climate modelling is a complex process, which requires accurate and complete metadata
(data describing data) in order to identify, assess and use the climate data stored in digital repositories.
The EU funded METAFOR project has developed a Common Information Model (CIM) to describe in a
standard way climate data and the models and modelling environments that produce this data. To establish the
CIM, METAFOR first considered the metadata models developed by many groups engaged in similar efforts in
Europe and worldwide (for example the US Earth System Curator), explored fragmentation and gaps as well
as duplication of information present in these metadata models, and reviewed current problems in identifying,
accessing or using climate data present in existing repositories. The CIM documents the “simulation context and
models”, i.e. the whys and wherefores and issues associated with any particular simulation.
Climate modelling is a complex process with a wide degree of variability between different models and
different modelling groups. To accommodate this, the CIM has been designed to be highly generic and flexible.
The climate modelling process which is "an activity undertaken using software on computers to produce data" is
described as separate UML packages. This fairly generic structure can be paired with more specific "controlled
vocabularies" in order to restrict the range of valid CIM instances.
METAFOR has been charged by the Working Group on Coupled Modelling (WGCM) via the Coupled
Model Inter-comparison Project (CMIP) panel to define and collect model and experiment metadata for CMIP5.
To do this, a web-based questionnaire will collect information and metadata from the CMIP5 modelling groups
on the details of the models used, how the simulations were carried out, how the models conformed to the specific
CMIP5 experiment requirements. The aim of the questionnaire is to document the climate models in sufficient
detail so that the CMIP5 data can be located and compared by a wide and diverse community, including those
researchers with an interest in the impacts and adaptations of climate change (e.g. IPCC’s WGII). A new set
of “controlled vocabulary” was devised to describe in a standard and structured way the dynamics, physics,
numerical schemes and other parameterisations of the several components (ocean, atmosphere, land surface, sea
ice, atmospheric chemistry, etc.) of the earth system models used in CMIP5.
The CMIP5 model documentation questionnaire is an ambitious metadata collection tool. It will provide
the most comprehensive metadata for a climate model inter-comparison project yet and plans for the community
governance of its associated standards and now being organised. The questionnaire’s close ties with the CIM will
ensure that the metadata for the CMIP5 model runs will be stored in a standard way, enabling the development of
tools to search for and compare CIM documents, and hence different climate model
SEVIRI Fire Radiative Power (FRP) Dataset
No full textThis document describes the SEVIRI Fire Radiative Power (FRP) Dataset archived at BADC/NEODC
Data Publication in the Meteorological Sciences: the OJIMS project
No full textHistorically speaking, scientific publication has mainly focussed on the analysis, interpretation and conclusions
drawn from a given dataset, as these are the information that can be easily published in hard copy text format
with the aid of diagrams. Examining the raw data that forms the dataset is often difficult to do, as datasets are
usually stored in digital media, in a variety of (often proprietary or non-standard) formats. This means that the
peer-review process is generally only applied to the methodology and final conclusions of a piece of work, and not
the underlying data itself. Yet for the conclusions to stand, the data must be of good quality, and the peer-review
process must be used to judge the data quality.
Data publication, involving the peer-review of datasets, would be of benefit to many sectors of the academic
community. For the data scientists, who often spend considerable time and effort ensuring that their data
and metadata is complete, valid and stored in an accredited data repository, this would provide academic credit
in the form of extra publications and citations. Data publication would benefit the wider community, allowing
discovery and reuse of useful datasets, ensuring their curation and providing the best possible value for money.
Overlay journals are a technology which is already being used to facilitate peer review and publication online.
The Overlay Journal Infrastructure for Meteorological Sciences (OJIMS) Project aimed to develop the
mechanisms that could support both a new (overlay) Journal of Meteorological Data and an Open-Access
Repository for documents related to the meteorological sciences. The OJIMS project was conducted by a
partnership between the UK’s Royal Meteorological Society (RMetS) and two members of the National Centre
for Atmospheric Science (NCAS), the British Atmospheric Data Centre (BADC) and the University of Leeds.
Conference delegates at the NCAS Conference in Bristol of 8-10 December 2008 were invited to complete
a survey to assess the potential implications for the meteorological sciences should a data journal and an
open access subject repository be created and operated. Supervised run-throughs of a demonstrator Journal of
Meteorological Data were also carried out by seven volunteers at the conference. The feedback from the surveys
and demonstrations became part of the reports and recommendations produced by the project. This included
discussion of the benefits to data creators, the review process, branding, version control and citations.
The project concluded that standard online journal technologies are suitable for the development and operation
of a data journal as they allow the use of all the functions of journals without the need to engineer new
solutions. The user surveys and interviews also showed that there is a significant desire in the meteorological
sciences community for a data journa
A Flexible Component based Access Control Architecture for OPeNDAP Services
No full textNetwork data access services such as OPeNDAP enable widespread access to data across user communities.
However, without ready means to restrict access to data for such services, data providers and data owners are
constrained from making their data more widely available. Even with such capability, the range of different
security technologies available can make interoperability between services and user client tools a challenge.
OPeNDAP is a key data access service in the infrastructure under development to support the CMIP5 (Couple
Model Intercomparison Project Phase 5). The work is being carried out as part of an international collaboration
including the US Earth System Grid and Curator projects and the EU funded IS-ENES and Metafor projects.
This infrastructure will bring together Petabytes of climate model data and associated metadata from over twenty
modelling centres around the world in a federation with a core archive mirrored at three data centres. A security
system is needed to meet the requirements of organisations responsible for model data including the ability to
restrict data access to registered users, keep them up to date with changes to data and services, audit access and
protect finite computing resources. Individual organisations have existing tools and services such as OPeNDAP
with which users in the climate research community are already familiar. The security system should overlay
access control in a way which maintains the usability and ease of access to these services. The BADC (British
Atmospheric Data Centre) has been working in collaboration with the Earth System Grid development team and
partner organisations to develop the security architecture. OpenID and MyProxy were selected at an early stage in
the ESG project to provide single sign-on capability across the federation of participating organisations.
Building on the existing OPeNDAP specification an architecture based on pluggable server side compo-
nents has been developed at the BADC. These components filter requests to the service they protect and apply
the required authentication and authorisation schemes. Filters have been developed for OpenID and SSL client
based authentication. The latter enabling access with MyProxy issued credentials. By preserving a clear separation
between the security and application functionality, multiple authentication technologies may be supported without
the need for modification to the underlying OPeNDAP application.
The software has been developed in the Python programming language securing the Python based OPeN-
DAP implementation, PyDAP. This utilises the Python WSGI (Web Server Gateway Interface) specification to
create distinct security filter components. Work is also currently underway to develop a parallel Java based filter
implementation to secure the THREDDS Data Server. Whilst the ability to apply this flexible approach to the
server side security layer is important, the development of compatible client software is vital to the take up of these
services across a wide user base. To date PyDAP and wget based clients have been tested and work is planned to
integrate the required security interface into the netCDF API. This forms part of ongoing collaboration with the
OPeNDAP user and development community to ensure interoperability
UKCP09: Spatially coherent projections
No full textThis document describes some of the issues surrounding providing spatially coherent projections within UKCP09 and how this has been addressed
UKCP09: Probabilistic projections of wind speed
No full textThis document describes the probabilistic projections of changes in 30-year mean wind speeds relative to 1961–1990 that have been produced for the UK Climate Projections 2009 (UKCP09). These are based on the same methodology previously used to produce other variables available within UKCP09
Eighth (Advanced) Along Track Scanning Radiometer ((A)ATSR) Users Bulletin and Summary of (A)ATSR Archive Quality Control Results
No full textRegular bulletin regarding (A)ATSR data quality
NERC ARSF Data Management Plan
No full textThe document is an agreed record of the data management needs and issues of the NERC Airborne Research and Survey Facility. It defines who is responsible for data management activities. It includes conditions of use and deposit to clearly express the ownership and rights associated with the data
