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Making Data a First Class Scientific Output: Data Citation and Publication by NERCâs Environmental Data Centres
No full textThe NERC Science Information Strategy Data Citation and Publication project aims to develop and formalise a method for formally citing and publishing the datasets stored in its environmental data centres. It is believed that this will act as an incentive for scientists, who often invest a great deal of effort in creating datasets, to submit their data to a suitable data repository where it can properly be archived and curated. Data citation and publication will also provide a mechanism for data producers to receive credit for their work, thereby encouraging them to share their data more freely
Mars Analysis Correction Data Assimilation: A Multi-Annual Reanalysis of Atmospheric Observations for the Red Planet
No full textEver-increasing numbers of atmospheric observations from orbiting spacecraft, and increasingly
sophisticated numerical atmospheric models, have recently permitted data assimilation
techniques to be applied to planets beyond the Earth. Mars is the first extra-terrestrial planet for
which reanalyses of the atmospheric state are now available.
The Thermal Emission Spectrometer (TES) on board NASA’s Mars Global Surveyor (MGS) has
produced an extensive atmospheric data set during its scientific mapping phase between 1999
and 2004. Nadir thermal profiles for the atmosphere below about 40 km altitude, and total dust
and water ice opacities, have been retrieved from TES spectra, covering almost three complete
Martian seasonal cycles (each seasonal cycle on Mars corresponds to 668.6 mean solar days,
and the Martian mean solar day is about 24 hours and 40 minutes). Note that dust on Mars plays
a key role in the weather and climate, mainly through its strong absorption of short wave radiation
with a short radiative relaxation timescale of 1-2 days. Assimilating dust opacities correctly is,
therefore, particularly important for atmospheric data assimilation on the Red Planet.
TES retrieved observations have been analysed by assimilation into a Mars general circulation
model (MGCM), making use of a sequential procedure known as the Analysis Correction scheme,
a form of successive corrections method which has proved simple and robust under Martian
conditions, even during the less-than-ideal MGS aerobraking period. The MGCM used at the
University of Oxford and at The Open University consists of a spectral dynamical solver and a
tracer transport scheme developed in the UK. Its package of state-of-the-art physical
parameterization routines is shared with the LMD-MarsGCM, developed by the Laboratoire de
Météorologie Dynamique in Paris (France).
One limitation of TES is that relatively few limb profiles are available, compared to nadir
soundings. Our MGS/TES reanalysis, therefore, does not include observations of temperature
above about 40 km altitude, nor 3D information on dust opacity (the vertical distribution of dust
opacity is prescribed assuming a well mixed dust layer with a rapid transition to a clear upper
atmosphere at a height which depends on latitude and season.
In September 2006 NASA’s Mars Reconnaissance Orbiter (MRO) started its mapping phase. The
Mars Climate Sounder (MCS) on board MRO is a radiometer with eight mid- and far-infrared
channels and one visible channel, which takes measurements in limb and off-nadir geometries.
Retrieved vertical profiles of temperature, dust and water ice opacities from MCS observations
can now be assimilated using the same scheme we used for TES, with the advantage of the
extension in altitude (thermal profiles can extend to above 80 km altitude, although errors become
larger at greater altitudes), the increased vertical resolution (~ 5km compared to > 10km for TES
nadir retrievals), and the direct information on the vertical distribution of dust and water ice.
Overall, the application of our data assimilation scheme to retrieved observations from TES and
MCS spans almost six complete Martian seasonal cycles. This represents a multi-annual
climatology for Mars, which has the advantage of being a complete, dynamically-balanced, fourdimensional
best-fit to observations for all the atmospheric variables, including those for which no
direct measurements are available (e.g. wind and surface pressure) and with regions of no
observations filled-in in a physically-consistent way.
The reanalysis represents, therefore, a unique opportunity to study the inter-annual variability of
the Martian weather and climate with respect to all its components, such as the dust cycle, the
water cycle, the CO2 cycle, the atmospheric tides and other prominent waves, such as high
latitude baroclinic waves.
In this contribution we present the first results of a complete assimilation of both datasets, using a
consistent model and data assimilation scheme, and highlight the challenges of combining TES
and MCS data assimilation to produce a multi-annual climatology. Particular attention will be
devoted to the inter-annual variability of the atmospheric thermal field in response to dust storm
activity. We will also provide an insight into the dynamics, looking in particular at the high latitude
winds, waves and polar vortices.
Our data assimilation products are freely available to the community for both science- and
engineering-oriented purposes. The British Atmospheric Data Centre (BADC,
http://badc.nerc.ac.uk) hosts our datasets, which, for the time being, are limited to the MGS/TES
reanalysis. People may contact the corresponding author in order to register their interest and be
updated about the status of the project. New versions of the MGS/TES reanalysis as well as the
MRO/MCS reanalysis will be made available through the BADC in future.
Interested people can download the current TES reanalysis dataset by registering at the BADC
and searching for the MACDA (“Mars Analysis Correction Data Assimilation”) project. The direct
link to the project is provided by the following URL:
http://badc.nerc.ac.uk/view/badc.nerc.ac.uk__ATOM__DE_095e8da2-cf02-11e0-8b7a-
00e08147026
Retrieval of Global Tropospheric Methane Distributions from IASI
No full textIn poster describes a scheme that has been developed at the Rutherford Appleton Laboratory to retrieve methane distributions from the IASI instrument on METOP. IASI is an infrared nadir viewing Fourier transform spectrometer, primarily sensitive to methane in the middle to upper troposphere. Methane is an important greenhouse gas, and knowledge of its distribution, sources and sinks, and trend within the atmosphere are important for our understanding of the current atmosphere and future climate. The ability to measure information on methane from space allows global methane distributions to be derived alongside seasonal and even longer term variations in its concentration. Here, results from our version 1 methane data are described, and their quality is illustrated by comparison to models and other satellite data. In addition, the impact of clouds on the results are investigated. This is found to be a critical source of error leading to anomalously high retrieved methane value
RAL Summer Student Christopher Brambley: Adding details of historic solar images from the Royal Observatory, Greenwich, to the UKSSDC database
No full textIn 2008, the UK Solar System Data Center (UKSSDC) recovered a large selection of solar images from underneath a stairwell in the University of Cambridge.
This presentation deals kinds with:
1. What kinds of image are in the collection.
2. Where you can go to browse the contents of this collection.
3. The possible uses of such images
Ionosondes: Past, present and future
No full textAs RAL Space celebrates 50 years in Space, it also looks back on its longest running experiment: the monitoring of the ionosphere with ionosondes. This presentation looks at the history of ionosondes, what has been learnt from them in the past, what they continue to tell us, and how they might develop in the future
E-infrastructure for climate and atmospheric science research
No full textRecent government in e-Infrastructure will transform aspects of environmental science by supporting both fundamental science and innovative uses of environmental data by the commmercial sector. The STFC Centre for Environmental Data Archival (CEDA) is heavily involved in two major projects: JASMIN - a NERC funded facility which will support both data archival and scientific data analysis, and CEMS - the Facility for Climate and Environmental Monitoring from Space - aimed at fostering knowledge exchange and commercial exploitation of environmental data. JASMIN and CEMS will share some hardware.
In this presentation, we concentrate on JASMIN, which will consist of multi-Petabyte fast reliable storage and co-located data analysis compute at the STFC Rutherford Appleton Laboratory, with satellite installations at Reading, Leeds and Bristol Universities. JASMIN is a response to the growing use of direct numerical simulation in the environmental sciences resulting in much higher demand for high performance computing. This growth in HPC is accompanied by a transition in its nature, with data intensive HPC becoming an ever increasing part of the mix. (For example, at the time of writing CEDA is currently evaluating the requirements in terms of storage and co-located analysis compute for three grants each of which is expected to produce in excess of 0.5 PB of data over the next three years - this on top of known data acquisition already measured in PB. Clearly every grant round could bring similar requirements.)
Such data intensive HPC is being carried out on on many different supercomputers, so it is no longer satisfactory to assume that putting storage alongside the HPC will solve the analysis problem (since such a solution, alone, could result in an NxN data transfer problem for data comparison between results on N supercomputers). Inevitably one needs to reduce the data transfer problem down to as close to Nx1 as possible - hence JASMIN - a facility configured for data storage AND analysis. For analysis, JASMIN will deploy a "private cloud" to allow the community to develop their own analysis environment using their favourite operating system configuration. JASMIN will also be used, along with a large tape facilities provided by STFC, to provide persistent storage for the archival and curation functions which CEDA also provides. These storage and computing advances will be supported by high-bandwidth network connectivity between key collaborating institutions (particularly supercomputing sites), both within the UK and in the Europe, and new light paths have been established alongside the JASMIN activity.
JASMIN: Joint Analysis System Meeting e-Infrastructure Need
Benchmarking OPeNDAP services for modern ESM data workloads
No full textExperience from the 5th Coupled Model Intercomparison Project (CMIP5)
suggests that serving today's Earth System Model outputs to end-users
is constrained by the effective bandwidth of global network links.
One solution is to provide higher-level data access services which
allow users to select only the data they require. OPeNDAP is a well
established RESTful protocol for subsetting data in the NetCDF data
model that has the potential to meet this need. However, for OPeNDAP
to be a viable alternative to basic file transfer, OPeNDAP services
must scale to the data volumes required to serve today's ESM data
whilst keeping server load at manageable levels.
We present the dapbench framework for testing the performance and
security constraints of OPeNDAP servers under serial and parallel
workloads. We compare the performance of commonly used OPeNDAP server
implementations for request patterns typical of high-level NetCDF
tools and analyse the affect of ESG Federation security filters on the
performance of serial and parallel workloads.
As a possible optimisation of OPeNDAP services we suggest constraining
the allowed requests to a cachable subset and evaluate the effect of
HTTP proxy caching performance. The results from these experiments
will be used to identify the challenges to effective use of OPeNDAP in
an analysis context
APPRAISE Final Report
No full textFinal report for the Aerosol Properties, Processes and Influences on the Earth's Climate (APPRAISE) programme. This was a UK NERC (Natural Environment Research Council) research programme designed to improve our ability to quantify the effects of atmospheric particles on the Earth's climate system.
The aims of APPRAISE were to investigate and understand the underlying properties of airborne particles that affect the lifecycle of aerosol particles which in the end are responsible for their effect on radiation and cloud formation (hence the aerosols direct and indirect radiative contributions to the earth’s radiation budget). The programme tackled the formation, transformation and interaction of particles in the atmosphere to establish and quantify key pathways in their lifecycle
Implementation of UML Schema to RDBM
No full textNumerous disciplines require information concerning phenomena implicitly or explicitly associated with a location relative to the Earth. Disciplines using Geographic Information (GI) in particular are those
within the earth and physical sciences, and increasingly those within social science and medical fields. Therefore geographic datasets are increasingly being shared, exchanged and frequently re-purposed
for uses beynd their original intended use.
The ISO Technical Committee 211 (ISO/TC 211) together with Open Geospatial Consortium (OGC) provide a series of standards and guidelines for developing application schemas which should:
a) capture relevant conceptual aspects of the data involved;
b) be sufficient to satisfy previously defined use-cases of a specific or cross-domain concerns.
In addition, the HollowWorld technology offers an accessible and industry-standardised methodology for creating and editing Application Schema UML models which conform to international standards for
interoperable GI [2]. We present a technology which seamlessly transforms an Application Schema UML model to a relational database model (RDBM). This technology, using the same UML information
model, complements the XML transformation of an information model produced by the FullMoon tool [2].
RDBMs exist to enable searching within a data collection, a process that has, over the decades, been heavily optimized. Moreover, modern non-relational DB [3] flavours (MongoDB, Cassandra,
NewSQL) are still in their infancy with associated disadvantages for ease of adoption, software reliability, etc. A UML schema, or better its XMI description, has, in contrast, an almost natural
mapping/transformation to an XSD schema and ISO19136 with well known applications, e.g. Fullmoon or Shape Change, supporting this approach. However, describing geographic information within a
widely accepted XML-encoded vendor-neutral format such as GML may not be the best option for persisting or searching operations.
Within a full model-driven approach the UML should remain at the centre of any implementation claiming to represent the model itself. In this context, a UML -> XSD -> RDBM transformation is not
possible because the both the XSD and RDBM, and even an OWL implementation, have the same goal: to represent the same model. In a typical scenario an ingested XML document is separated into core
and ancillary data: the core data map to a set of relational tables, the ancillary to a single XML-type field. This approach works well when the core data are a fraction of the whole document, and even better
if the main aim of the RDBM is not to simply return other XML objects