2 km resolution rain rate data from Met Office's Wardon Hill C-band rain radar, Dorset, England as part of the NIMROD, very short range forecasting system used by the Met Office. 1 km rain rate data are available from 2006 until present. Radar images from the C-band (5.3 cm wavelength) radar are received by the Nimrod system 5 minute intervals respectively. Please note that this radar is operated for research purposes only and thus subject to changes in operation and data are subject to interruptions. Data from the Cobbacombe Cross, Dean Hill or Jersey radars provide coverage for the same area covered by the Wardon Hill radar.

The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) was organized under the auspices of Atmospheric Chemistry and Climate (AC&C), a project of International Global Atmospheric Chemistry (IGAC) and Stratospheric Processes And their Role in Climate (SPARC) under International Geosphere Bisosphere Programme (IGBP) and World Climate Research Programme (WCRP). The Atmospheric Chemistry and Climate Model Intercomparison Project (ACC-MIP) consists of several sets of simulations that have were designed to facilitate useful evaluation and comparison of the AR5 (Intergovernmental Committee on Climate Change Assessment Report 5) transient climate model simulations. This dataset contains measurements from climate simulations from GFDL of the 20th century and the future projections, which output feedback between dynamics, chemistry and radiation in every model time step. The data are collected from running the latest set of ozone precursor emissions scenarios, which output tropospheric ozone changes from 1850 to 2100.

2 km resolution rain rate data from Met Office's Predannack C-band rain radar, Cornwall, England as part of the NIMROD, very short range forecasting system used by the Met Office. 2 km rain rate data are available from 2004 until present. Radar images from the C-band (5.3 cm wavelength) radar are received by the Nimrod system 5 minute intervals respectively.

The AATSR Reprocessing for Climate (ARC) dataset consists of Advanced Along-Track Scanning Radiometer (AATSR) multimission data which has been reprocessed using various algorithms and in-situ contemporaneous measurements, to provide update retrievals of Sea Surface Temperature (SST) and assess their accuracy. ARC reprocesses the ATSR1, ATSR2 and AATSR data using new cloud detection and SST retrievals. The main ARC objective was to reduce regional biases in retrieved sea surface temperature (SST) to less than 0.1 K for all global oceans while creating a very homogeneous record with a stability (lack of drift in the observing system and analysis) of 0.05 K decade. The Level 3 ARC data products are available for ATSR1, ATSR2 and AATSR and in the version 1 release are currently available from 1991 to 2009, producing a homogeneous record of sea surface temperature for this period. Version 1.1 data are available. The previous version 1 data continues to be available. The ARC project was led by Chris Merchant of the University of Edinburgh/NCEO and funded by NERC and the UK Government.

Data from the DIAMET (DIAbatic influences on Mesoscale structures in ExTratropical storms, NE/I005234/1) project, part of the Storms Risk Mitigation NERC (Natural Environment Research Council) research programme 2009-2014. DIAMET used the FAAM (Facility for Airborne Atmospheric Measurements) BAE-146 aircraft, ground-based and airborne instruments and radar together with modelling studies to forge a better understanding and prediction of mesoscale structures in synoptic-scale storms. This is determined by focusing an incident laser beam on particles, and whenever a particle passes through the beam, a shadow is generated and imaged onto the diode array. These images are part of this dataset along with flight summaries. The DIAMET project aimed to better the understanding and prediction of mesoscale structures in synoptic-scale storms. Such structures include fronts, rain bands, secondary cyclones, sting jets etc, and are important because much of the extreme weather we experience (e.g. strong winds, heavy rain) comes from such regions. Weather forecasting models are able to capture some of this activity correctly, but there is much still to learn. By a combination of measurements and modelling, mainly using the Met Office Unified Model (UM), the project worked to better understand how mesoscale processes in cyclones give rise to severe weather and how they can be better represented in models and better forecast. The project is organised into three sections. Real mesoscale structures in the atmosphere have been examined, using high-resolution in situ and radar measurements to derive their morphology and dynamics. The key to the latter is to calculate the production of potential vorticity by diabatic processes - especially phase changes of water (vapour/liquid/ice) and air-sea fluxes of sensible and latent heat. The associated high-resolution modelling programme will use the UM to simulate a representative number of events, diagnosing the PV tendency in the model and comparing with the measurements. Sensitivity studies and further diagnostics with the model will reveal the sensitivity of the forecasts to the correct representation of these processes and the dynamical consequences of diabatically-generated PV, both on the mesoscale and larger scales. Two student projects have investigated the role of boundary-layer processes in storm behaviour and conduct a statistical investigation of mesoscale precipitation features, based on archived radar and wind profiler data. Examination of particular physical processes and the way these are represented in forecast models. Convection cannot be explicitly represented in current large-scale models (it is just beginning to be resolvable by high-resolution local-area models) so it needs to be parameterised. The schemes that are used are not optimised for mid-latitude storms, where convection often initiates at altitude rather than at the Earth's surface. A combination of novel diagnostics and new (or modified) schemes aimed at improving the representation of convection will be developed. Also addressed here will be the derivation of air-sea fluxes of heat and momentum from aircraft flights, and their use (as part of a larger, ongoing international project) to derive a better parameterisation for these quantities in high wind conditions. Lastly, microphysical measurements made with the FAAM aircraft will be used to derive latent heating/cooling rates as a function of the microphysical environment and used to improve the model simulations in the first WP and to improve microphysical parameterisations in the UM. The problem of predictability will be addressed using a combination of ensemble and data assimilation techniques. A unique archive of forecast ensembles produced at the Met Office will be exploited to determine how well the forecast ensemble actually generates realistic mesoscale features, and the skill with which this is done (using standard measures of skill). Model errors in representing convection, air-sea fluxes and microphysics will be investigated to determine their impact on the forecasts for different flow conditions. The relationship between different model variables on the mesoscale is poorly known at present and this will be investigated using ensembles and the results of the measurement programme. Finally, novel approaches to data assimilation will be investigated.

Theme 5 - Cryosphere and Polar Oceans - of the National Centre for Earth Observation (NCEO) is aimed at resolving uncertainties in future climate and sea-level arising from behaviour of the cryosphere. The data brings together altimetry, interferometry and gravimetry from satellites, coupled with numeric models. Ice thickness data used by Katharine Giles, Seymour Laxon and Andy Ridout in their paper "Circumpolar thinning of Arctic sea ice following the 2007 record ice extent minimum" (Geophysical Research Letters, Vol. 35, L22502, doi:10.1029/2008GL035710, 2008) are part of this dataset along with others to be submitted to the NEODC at a later time.

This dataset collection contains measurements from Infrared Atmospheric Sounding Interferometer (IASI) instrument on-board the Eumetsat Polar System Metop-A satellite. The IASI is designed to measure the infrared spectrum emitted by the Earth. IASI provides infrared soundings of the temperature profiles in the troposphere and lower stratosphere, moisture profiles in the troposphere, and some of the chemical components playing a key role in the climate monitoring, global change and atmospheric chemistry. Data were directly acquired from Eumetsat and are held at the NERC Earth Observation Data Centre (NEODC).

The Global Ozone Monitoring Experiment–2 (GOME–2), is an optical spectrometer, fed by a scan mirror which enables across–track scanning in nadir, as well as sideways viewing for polar coverage and instrument characterisation measurements using the moon. The scan mirror directs light into a telescope, designed to match the field of view of the instrument to the dimensions of the entrance slit. This scan mirror can also be directed towards internal calibration sources or towards a diffuser plate for calibration measurements using the sun. This dataset collection contains vertical profiles of ozone and other trace gases from the GOME-2 instrument on-board the Eumetsat Polar System (EPS) Metop-A satellite. GOME–2 comprises four main optical channels which focus the spectrum onto linear silicon photodiode detector arrays of 1024 pixels each, and two Polarisation Measurement Devices (PMDs) containing the same type of arrays for measurement of linearly polarised intensity in two perpendicular directions. GOME–2 senses the Earth’s Backscattered Radiance and Extraterrestrial Solar Irradiance in the ultraviolet and visible part of the spectrum (240 – 790 nm). The detected signals are preprocessed on board and then transmitted to ground for full data processing and generation of maps. The recorded spectra are used to derive a detailed picture of the total atmospheric content of ozone and the vertical ozone profile in the atmosphere, vertical profiles of ozone, nitrogen dioxide, water vapour, oxygen / oxygen dimmer, bromine oxide and other trace gases, as well as aerosols.

Data from the Infrared Atmospheric Sounding Interferometer (IASI) instrument on-board the Eumetsat Polar System Metop-B satellite. The IASI is designed to measure the infrared spectrum emitted by the Earth. IASI provides infrared soundings of the temperature profiles in the troposphere and lower stratosphere, moisture profiles in the troposphere, and some of the chemical components playing a key role in the climate monitoring, global change and atmospheric chemistry. Data were directly acquired from Eumetsat.

Single-polar products from the Met Office's Hameldon Hill C-band rain radar, Lancashire, England. Data include reflectivity and augmented Doppler products from June 2005 and December 2012 respectively. The radar is a C-band (5.3 cm wavelength) radar and data are received by the Nimrod system at 5 minute intervals.