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The CMIP5 Model Documentation Questionnaire: Development of a Metadata Retrieval System for the Metafor Common Information Model
No full textThe EU METAFOR Project (http://metaforclimate.eu) has created a web-based model documentation questionnaire to collect metadata from the modelling groups that are running simulations in support of the Coupled Model Intercomparison Project - 5 (CMIP5). The CMIP5 model documentation questionnaire will retrieve information about the details of the models used, how the simulations were carried out, how the simulations conformed to the CMIP5 experiment requirements and details of the hardware used to perform the simulations. The metadata collected by the CMIP5 questionnaire will allow CMIP5 data to be compared in a scientifically meaningful way.
This paper describes the life-cycle of the CMIP5 questionnaire development which starts with relatively unstructured input from domain specialists and ends with formal XML documents that comply with the METAFOR Common Information Model (CIM).
Each development step is associated with a specific tool. (1) Mind maps are used to capture information requirements from domain experts and build a controlled vocabulary, (2) a python parser processes the XML files generated by the mind maps, (3) Django (python) is used to generate the dynamic structure and content of the web based questionnaire from processed xml and the METAFOR CIM, (4) Python parsers ensure that information entered into the CMIP5 questionnaire is output as CIM compliant xml, (5) CIM compliant output allows automatic information capture tools to harvest questionnaire content into databases such as the Earth System Grid (ESG) metadata catalogue.
This paper will focus on how Django (python) and XML input files are used to generate the structure and content of the CMIP5 questionnaire. It will also address how the choice of development tools listed above provided a framework that enabled working scientists (who we would never ordinarily get to interact with UML and XML) to be part the iterative development process and ensure that the CMIP5 model documentation questionnaire reflects what scientists want to know about the models
Patterns of precipitation: fine scale rain dynamics in South of England
No full textA poster to show the patterns of precipitation on a fine scale dynami
Interpretation and use of future snow projections from the 11-member Met Office Regional Climate Model ensemble
No full textThis report describes how to interpret the 11-member Met Office Regional Climate model ensembles of future snow projections. Daily values of snowfall rate are available at 25 km resolution
from the ensemble of 11 Met Office regional climate model (RCM) variants run for UKCP09. This ensemble was run for the period 1950–2099, driven by the UKCP09 Medium scenario of future emissions of greenhouse gases and aerosols
Applying the Earth System Grid Security System in a Heterogeneous Environment of Data Access Services
No full textCEDA (Centre for Environmental Data Archival) based at STFC Rutherford Appleton Laboratory is host to
the BADC (British Atmospheric Data Centre) and NEODC (NERC Earth Observation Data Centre) with data
holdings of over half a Petabyte. In the coming months this figure is set to increase by over one Petabyte through
the BADC’s role as one of three data centres to host the CMIP5 (Coupled Model Intercomparison Project Phase 5)
core archive of climate model data. Quite apart from the problem of managing the storage of such large volumes
there is the challenge of collating the data together from the modelling centres around the world and enabling
access to these data for the user community.
An infrastructure to support this is being developed under the US Earth System Grid (ESG) and related
projects bringing together participating organisations together in a federation. The ESG architecture defines
Gateways, the web interfaces that enable users to access data and data serving applications organised into Data
Nodes. The BADC has been working in collaboration with US Earth System Grid team and other partners to
develop a security system to restrict access to data. This provides single sign-on via both OpenID and PKI based
means and uses role based authorisation facilitated by SAML and OpenID based interfaces for attribute retrieval.
This presentation will provide an overview of the access control architecture and look at how this has been
implemented for CEDA.
CEDA has developed an expertise in data access and information services over several years through a
number of projects to develop and enhance these capabilities. Participation in CMIP5 comes at a time when a
number of other software development activities are coming to fruition. New services are in the process of being
deployed alongside services making up the system for ESG. The security system must apply access control across
this heterogeneous environment of different data services and technologies. One strand of the development efforts
within CEDA has been the NDG (NERC Datagrid) Security system. This system has been extended to interoperate
with ESG, greatly assisted by the standards based approach adopted for the ESG security architecture. Drawing
from experience from previous projects the decision was taken to refactor the NDG Security software into a
component based architecture to enable a separation of concerns between access control and the functionality of a
given application being protected.
Such an approach is only possible through a generic interface. At CEDA, this has been realised in the
Python programming language using the WSGI (Web Server Gateway Interface) specification. A parallel Java
filter based implementation is also under development with our US partners for use with the THREDDS Data
Server. Using such technologies applications and middleware can be assembled into custom configurations to
meet different requirements. In the case of access control, NDG Security middleware can be layered over the top
of existing applications without the need to modify them. A RESTful approach to the application of authorisation
policy has been key in this approach. We explore the practical implementation of such a scheme alongside the
application of the ESG security architecture to CEDA’s OGC web services implementation COWS
RAPID-WATCH and the RAPID Data Centre
No full textThe RDC is a collaboration of the British Oceanographic Data Centre (BODC) and the British Atmospheric Data Centre (BADC). The group was formed for the RAPID Climate Change Programme and continues to work closely together throughout RAPID-WATCH (”Will the Atlantic Thermohaline Circulation Halt?”)
Why should NERC pay for BADC?
No full textSome background NERC and BADC.
What value is NERC expecting from the BADC.
Evidence of that value is being achieved.
Conclusions
UK Climate Change Projections Report
No full textThe UK Climate Projections (UKCP09) provide projections of climate change for the UK, giving greater spatial and temporal detail, and more information on uncertainty, than previous UK climate scenarios.
This report is designed for those who wish to find out more about the purpose and design of the UKCP09 methodology for producing the probabilistic projections of climate change, and is drafted to suit a range of levels of expertise. It shows some examples of projections; the full set of results is available through
the User Interface and the pre-prepared maps and graphs, with key findings presented in the Briefing Report
