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FAMOUS-CI, a fast Earth System GCM
No full textFAMOUS is a low resolution, fast version of the HadCM3 coupled atmosphere-ocean general circulation model, which runs without flux adjustments. Basing FAMOUS on HadCM3 means its results are directly traceable to a widely used AOGCM, giving confidence in its results. As part of the UK QUEST Earth System Model project, FAMOUS has been improved and expanded to include the terrestrial and marine carbon cycles. FAMOUS has also been coupled to the GLIMMER ice-sheet model, allowing all the main influences on Quaternary climate to interact fully.
The carbon cycle is represented by the HadOCC NPZD marine carbon cycle model, and the MOSES2.2 tiled land scheme. TRIFFID is used to simulate dynamic vegetation. Both the pre-industrial climate and climate sensitivity of FAMOUS compare well with HadCM3, suggesting that the lower resolution of FAMOUS is not a significant problem. FAMOUS-C can simulate over 100 years of climate per day using 8 processors of a cluster, making both millennial-scale transient runs and large ensembles feasible
MOLES-v3 Information Model
No full textThe Metadata Objects for Linking Environmental Sciences (MOLES) model has been developed within the Natural Environment Research Council (NERC) DataGrid project [NERC DataGrid] to fill a missing part of the ‘metadata spectrum’. It is a framework within which to encode the relationships between the tools used to obtain data, the activities which organised their use, and the datasets produced. MOLES is primarily of use to consumers of data, especially in an interdisciplinary context, to allow them to establish details of provenance, and to compare and contrast such information without recourse to discipline-specific metadata or private communications with the original investigators [Lawrence et al 2009]. MOLES is also of use to the custodians of data, providing an organising paradigm for the data and metadata.
The work described in this paper is a high-level view of the structure and content of a recent major revision of MOLES (v3.3) carried out as part of a NERC DataGrid extension project. The concepts of MOLES v3.3 are rooted in the harmonised ISO model [Harmonised ISO model] - particularly in metadata standards (ISO 19115, ISO 19115-2) and the ‘Observations and Measurements’ conceptual model (ISO 19156). MOLES exploits existing concepts and relationships, and specialises information in these standards.
A typical sequence of data capturing involves one or more projects under which a number of activities are undertaken, using appropriate tools and methods to produce the datasets. Following this typical sequence, the relevant metadata can be partitioned into the following main sections – helpful in mapping onto the most suitable standards from the ISO 19100 series.
• Project section
• Activity section (including both observation acquisition and numerical computation)
• Observation section (metadata regarding the methods used to obtained the data, the spatial and temporal sampling regime, quality etc.)
• Observation collection section
The key concepts in MOLES v3.3 are:
a) the result of an observation is defined uniquely from the property (of a feature-of-interest), the sampling-feature (carrying the targeted property values), the procedure used to obtain the result and the time (discrete instant or period) at which the observation takes place.
b) an ‘Acquisition’ and a ‘Computation’ can serve as the basis for describing any observation process chain (procedure). The ‘Acquisition’ uses an instrument – sensor or human being – to produce the results and is associated with field trips, flights, cruises etc., whereas the ‘Computation’ class involves specific processing steps. A process chain may consist of any combination of ‘Acquisitions’ and/or ‘Computations’ occurring in parallel or in any order during the data capturing sequence.
c) The results can be organised in collections with significantly more flexibility than if one used the original project alone
d) the structure of individual observation collections may be domain-specific, in general; however we are investigating the use of CSML (Climate Science Modelling Language) for atmospheric data
The model has been tested as a desk exercise by constructing object models for scenarios from various disciplines.
References
NERC DATAGRID: http://ndg.nerc.ac.uk
LAWRENCE ET. AL. ,Information in environmental data grids, Phil. Trans. R. Soc. A, March 2009 vol. 367 no. 1890 1003-1014
ISO HARMONISED MODEL: All relevant ISO standards for geographic metadata from the TC211 series (eg. ISO 19xxx), and is harmonised within a formal UML description in the ‘HollowWorld’ packages available at https://www.seegrid.csiro.au/twiki/bin/view/AppSchemas/HollowWorl
National Centre for Earth Observation Top Stories 2008/09
No full textThe National Centre for Earth Observation is one of the NERC's research and collaborative centres. The NCEO has now been running for just over a year (from April 2008). This brochure is a selection of NCEO's early scientific achievements
Trends in long-term synoptic observations of clouds and precipitation at Vernadsky
No full textReanalysis data shows as a consequence a significant reduction in sea ice in the area of the Western Antarctic Peninsula. This is thought to have caused the temperature increase observed in the records, which make the Western Antarctic Peninsula one of the fastest warming regions on Earth. Recently performed comprehensive analyses of synoptic observations of cloud parameters recorded at the Antarctic base Faraday/ Vernadsky for the period 1960 to 2005 have shown that one effect of the warming is a significant increase in the annual mean of the total cloud cover. The strongest and most significant positive seasonal trend was found in winter, but positive tendencies are observable in all seasons. A direct consequence of these changes is an increase in the number of days on which some form of precipitation is recorded. In combination with the rising air temperatures this leads to significant changes in the phase of the observed precipitation. The number of non-frozen precipitation events has increased by 2.4 events per year. Though the highest seasonal trend is observed in summer (1.2 events per year), the increases in spring and autumn will probably have the most impact
A geo-referenced database for surface roughness parameters over Greater Manchester
No full textIn this presentation information on urban morphology available for Greater Manchester in northwest England is analysed, and an approach to derive the roughness parameters needed to model the surface sensible heat flux is described. A surface morphologic database for Greater Manchester, developed from analysis of digitised geo-referenced data of the surface elements height (Cities Revealed Building Heights Data and Environment Agency data), aerial photography, maps and field surveys, is described. Initially, data of a sample area of Greater Manchester are analysed. Land-use categories are established for Greater Manchester, and reference morphologic parameters are attributed to each land-use category. The fraction of urbanised area and model surface morphologic parameters, such as the surface elements height (zH) and frontal area index (λF), are estimated and mapped over a rectangular grid of 1km x 1km resolution, for the Greater Manchester study area. Using these values it was possible to obtain model estimates of the zero-plan displacement height (zD) and roughness height for momentum (z0M) for each domain cell
