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STFC Centre for Environmental Data Archival (CEDA)Annual Report 2010 (April 2009-March 2010)
No full textThe mission of the Centre for Environmental Archival is to deliver long term curation of scientifically important environmental data at the same time as facilitating the use of data by the environmental science community.
CEDA was established by the amalgamation of the activities of two of the Natural Environment Research Council (NERC)
designated data centres: the British Atmospheric Data Centre, and the NERC Earth Observation Data Centre. The process began with administrative functions (in 2005) and has proceeded steadily since, as new activities have and continue to be accreted into CEDA. Until 2008, the constituent parts of CEDA reported independently to NERC, but in 2009 we produced the first public report for CEDA. We are pleased to present here in our second annual report, evidence of the range of activities undertaken in CEDA, from methodical management of data, through innovative software development, to a close engagement with the scientific community – gathering and delivering the requirements of 21st century digital environmental science.
Digital curation involves ensuring that data remains both safe and fit for purpose. For most of us it is intangible, we're not really aware of it except for when things go wrong. We have considerable experience of personal curation failings: we all know someone (or have had it happen to us) who has suffered a hard-drive failure, but just as important is recognising the inability to understand the contents of a spreadsheet we created a few months ago as a curation failure resulting in unneeded angst and repetition of effort. Hopefully, we have less experience of service curation failure, even as we rely on remotely managed data (some of which we create, some of which we consume). From banks to insurance companies, from facebook to flickr, as our world of digital data expands, so too does our dependency. All service providers carry out curation; a delicate balancing act between preserving the bits and bytes, and evolving the way those bits and bytes are stored and understood to support new products and services. So too in science, the journal article is no longer the only important product of science – more and more of the underlying data is being preserved both as evidence for what was done, and as raw material for new and interesting syntheses of information. Digital curation is now part and parcel of doing science, ensuring we understand what was done and can repeat it, even as we have forgotten the doing of it.
CEDA plays its part in curation and evolution by endeavouring to preserve for posterity what has been done and facilitating new and interesting ways of exploiting data for the future. Such facilitation now includes both building new delivery services (which is what the users see) and new information services to ensure the data is always fit for purpose and available for reuse (the hard part of which most users never see). It also includes acquiring third party data as necessary and engaging with producers and users
of data alike. In this, the second annual report of CEDA, we present some of our curation and facilitation accomplishments from the last year, beginning with a summary of important events and collaborations. We follow that with some selected highlights, and some statistical reports, including a financial summary. We then present our targets for next year. CEDA has done much, well, and of necessity; only some of what we have done is presented here, and we trust that you find something of interest
Future changes in lightning from the UKCP09 ensemble of regional climate model projections
No full textThis technical note uses the UKCP09 ensemble projections of regional climate models to investigate the potential future changes in lightning strikes over the UK
Modelling marine stratocumulus and its radiative properties
No full textThe radiative properties of sub-tropical marine stratocumulus, which cover large regions and affect the global climate, are influenced by the presence of drizzle, aerosols, and cloud-top entrainment, all of which are coupled. VOCALS, the VAMOS Ocean-Cloud-Atmosphere-Land Study, is examining the climate system of the southeast Pacific to reduce uncertainties in current and future climate projections, especially those associated with marine stratocumulus and coupled ocean-atmosphere processes. As part of VOCALS-UK we are investigating the small-scale structure and microphysics of marine stratocumulus, and hence its radiative properties, by using the UK Met Office Large Eddy Model (LEM). The model simulations are validated against measurements from the BAe-146 research aircraft obtained during the VOCALS field campaign over the southeast Pacific in October and November 2008.
We have incorporated the new Morrison microphysics scheme into the LEM and compared simulations with the Morrison scheme to those from the LEM standard bulk microphysics. Simulations with the Morrison scheme tend to produce a deeper marine stratocumulus with increased Liquid Water Path (LWP), but reduced precipitation compared to the standard LEM scheme. The cloud droplet effective radii (Re) is increased as not all the cloud condensation nuclei (CCN) are activated, so that radiative cooling at the cloud tops, vertical mixing and cloud top entrainment are all reduced. Overall, results from the Morrison scheme are in better agreement with the measurements.
We then carried out sensitivity studies to quantify the effects of increased CCN number concentration, entrainment of clean air at cloud top, and precipitation on the simulated clouds and their radiative properties, including the inhomogenity over different domain sizes. Increased CCN results in reduced Re, increased albedo, cloud top cooling, vertical mixing and entrainment, and reduced LWP, inhomogeneity and precipitation. Entrainment of clean air results in slightly increased Re, reduced albedo, cooling, vertical mixing, entrainment and LWP, and increased inhomogeneity and precipitation. Precipitation removes liquid water from the cloud, but evapouration of the raindrops then moistens and cools the air below, reducing LWP, vertical mixing and albedo, and increasing cloud layer inhomogeneity. Furthermore the effects are coupled with increased CCN leading to reduced precipitation, and precipitation removing CCN.
The amount of horizontal inhomogeneity in the albedo of the simulated cloud tops over different domain sizes is also examined. Increasing CCN reduces the inhomogeneity across all domain sizes, while both the entrainment of clean air and precipitation increase the inhomogeneity with the greatest increases over the largest domains
The RAPID ocean observation array at 26.5°N in the HadCM3 model
No full textThe RAPID array consists of several moorings at about 26°N in the Atlantic that measure temperature and salinity from which the meridional overturning circulation (MOC) and its components at this latitude can be determined. The main aim of the VALue Of the RAPID array (VALOR) project is to assess the value of the RAPID array observations for predictions of the Atlantic MOC and its impact on
climate. In addition, the project will explore a range of issues concerning the design of a potentional MOC prediction system. One of the models used in this work is the Hadley Centre HadCM3 model. In this work we have investigated the potential issues that may arise
when comparing RAPID array observations and its derived transports with model variables. This could be for comparing an ocean assimilation or an ocean forecast with observations. The main issue is the low resolution of the HadCM3 ocean (1.25°x1.25°), which changes the bathymetry. As an example, most of Florida does not exist, so the
Florida Straits, which is a crucial part of the observations, is missing. The possibility of moving the model array further north to where there is a Florida is investigated, but no convincing reason to do so is found
UK Climate Projections science report: Projections of future daily climate for the UK from the Weather Generator
No full textIn this report the UK Climate Projections (UKCP09) Weather Generator (WG) is introduced. This report covers the needs and principles and how it can be used to assess changes in extremes at spatial and temporal scales finer than the UKCP09 probability distribution functions (PDFs) can provide. Further, an illustration in the way the WG is perturbed to account for future climate change works and some illustrative maps of changes in extremes across the UK are also provide
Climate Data from the BADC
No full textThe BADC provides data support for numerous NERC climate related projects such as RAPID/RAPID-WATCH, QUEST, FREE, as well as national projects such as UKCP09, LINK and international projects like CMIP5, IPCC-DDC. In addition, there are climate datasests from the Met Office available (HadCM3, HadGEM, Gridded datasets, observations) and the CRU.
The BADC also provide interfaces to the data to make more accessible to the user community
Unlocking the full potential of Earth Observation - a presentation of the work of the National Centre for Earth Observation (NCEO)
No full textA presentation about unlocking the full potential of Earth Observatio
Pragmatic service development and customisation with the CEDA OGC Web Services framework
No full textThe CEDA OGC Web Services framework (COWS) emphasises rapid service development by providing a
lightweight layer of OGC web service logic on top of Pylons, a mature web application framework for the Python
language. This approach gives developers a flexible web service development environment without compromising
access to the full range of web application tools and patterns: Model-View-Controller paradigm, XML templating,
Object-Relational-Mapper integration and authentication/authorization. We have found this approach useful for
exploring evolving standards and implementing protocol extensions to meet the requirements of operational
deployments.
This paper outlines how COWS is being used to implement customised WMS, WCS, WFS and WPS ser-
vices in a variety of web applications from experimental prototypes to load-balanced cluster deployments serving
10-100 simultaneous users. In particular we will cover 1) The use of Climate Science Modeling Language
(CSML) in complex-feature aware WMS, WCS and WFS services, 2) Extending WMS to support applications
with features specific to earth system science and 3) A cluster-enabled Web Processing Service (WPS) supporting
asynchronous data processing.
The COWS WPS underpins all backend services in the UK Climate Projections User Interface where users
can extract, plot and further process outputs from a multi-dimensional probabilistic climate model dataset. The
COWS WPS supports cluster job execution, result caching, execution time estimation and user management. The
COWS WMS and WCS components drive the project-specific NCEO and QESDI portals developed by the British
Atmospheric Data Centre. These portals use CSML as a backend description format and implement features such
as multiple WMS layer dimensions and climatology axes that are beyond the scope of general purpose GIS tools
and yet vital for atmospheric science applications