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  • The Hydrological Radar Experiment (HYREX) was a UK Natural Environment Research Council (NERC) Special Topic which ran from May 1993 to April 1997. The broad aim of HYREX was to gain a better understanding of rainfall variability, as sensed by weather radar, and how this variability impacts on river flow at the catchment scale. Six projects were funded involving groups from CEH Wallingford (formerly the Institute of Hydrology), the Rutherford Appleton Laboratory and the universities of London (Imperial College and University College), Newcastle, Reading (including the Joint Centre for Mesoscale Meteorology or JCMM) and Salford. The projects ranged from research on improved precipitation measurement using polarisation and vertical pointing radars, through network design of radar/raingauge networks and spatial-temporal modelling of rainfall fields, to rainfall forecasting based on stochastic and meteorological concepts. An overview of the six HYREX projects and a list of the members of the HYREX Steering Committee are available as separate documents. The experiment was centred on the Brue catchment in Southwest England. The common experimental infrastructure comprised two national network C-band radars at Wardon Hill (Doppler) and Cobbacombe Cross, a purpose-built dense raingauge network, an automatic weather station (AWS), an automatic soil water station (ASWS), and a river gauging station. These instruments have provided a continuous record throughout HYREX. Further instrumentation, deployed on an occasional basis, included an experimental S-band Doppler dual polarisation radar at Chilbolton and an associated line network of rapid-response raingauges (operated by Rutherford Appleton Laboratory), a transportable vertically pointing X- band radar (operated by the University of Salford), the UK Meteorological Office (UKMO) Research Flight and radiosonde network, and a disdrometer (operated by CEH Wallingford). The JCMM provided output from special runs of the UKMO Unified Model (UM). Infrastructure support was provided by the UKMO, the Environment Agency (EA), NERC, Rutherford Appleton Laboratory, the Ministry of Agriculture, Fisheries and Food (MAFF) and the water utilities. The occasional deployment of some instruments was scheduled to coincide with a number of one or two day Intense Observing Periods (IOPs), triggered by meteorologically interesting conditions, during which radiosonde ascents and aircraft overflights were made, and for which special runs of the Unified Model were made.

  • The Rain in Cumulus over the Ocean (RICO) was a US-led international project to study trade wind cumulus clouds in the Caribbean. The main objective was to characterise and understand the properties of trade wind cumulus at all scales, with particular emphasis on understanding the warm rain process and determining its importance. The field campaign took place near Antigua and Barbuda from the 17th of November 2004 to the 24th of January 2005. The UK participation to RICO involved ground-based measurements and the use of the FAAM aircraft based at Antigua, from the 5th to the 28th of January 2005.

  • The Convective Storm Initiation Project (CSIP) aimed to further the understanding of the mechanisms responsible for the initiation of precipitating convection in the maritime environment of southern England; i.e. to understand why convective clouds form and develop into precipitating clouds in a particular location. The project was centred on the 3 GHz (CAMRa) and 1275 clear-air (ACROBAT) radars at Chilbolton and used a number of the new UK Universities' Facility for Atmospheric Measurement (UFAM) mobile instruments. These include three sodars, a Doppler Lidar, a wind profiler, an aerosol and ozone lidar, a network of automatic weather stations, mobile radiosonde stations and a Cessna aircraft. This dataset includes measurements of wind speeds and wind directions and aerosol concentrations.

  • This dataset contains Climate Hazards Group Infrared Precipitation with Stations (CHIRPS) Quasi-global satellite and observation based precipitation estimates over land from 1981 to near-real time. Spanning 50°S-50°N (and all longitudes), starting in 1981 to near-present, CHIRPS incorporates 0.05° resolution satellite imagery with in-situ station data to create gridded rainfall time series for trend analysis and seasonal drought monitoring.

  • This dataset contains Climate Hazards Group Infrared Precipitation with Stations (CHIRPS) Quasi-global pentadal satellite and observation based precipitation estimates over land from 1981 to near-real time. Spanning 50°S-50°N (and all longitudes), starting in 1981 to near-present, CHIRPS incorporates 0.05° resolution satellite imagery with in-situ station data to create gridded rainfall time series for trend analysis and seasonal drought monitoring.

  • This CD-ROM set contains the Volume 5 Near-surface meteorological analyses and Total and convective precipitation data collection. The data covers a 24 month period, 1987-1988, and all but one are mapped to a common spatial resolution and grid (1 degree x 1 degree). Temporal resolution for most datasets is monthly; however, a few are at a finer resolution (e.g., 6-hourly). This dataset contains data covering Near-surface meteorological analyses, hybrid products and total and convective precipitation

  • Simulations made using the HadGEM2 model in AMIP (atmosphere only) configuration for the SAPRISE (South Asian PRecIpitation: A SEamless assessment) project. The SAPRISE project investigates the impacts of aerosols on the South Asian Monsoon using historical simulations forced with anthropogenic aerosols i.e. sulphur dioxide, black carbon and biomass burning aerosols. The simulations cover the period from 1850-2000.

  • An ensemble of simulations made using the Unified Model version 6.6 (HadGEM2) in AMIP (atmosphere only) configuration for the SAPRISE (South Asian PRecIpitation: A SEamless assessment) project. The simulations are used to investigate the impacts of aerosols on the South Asian Monsoon. The four-member ensemble of simulations are forced with anthropogenic-only aerosols i.e. sulphur dioxide, black carbon and biomass burning aerosols. The simulations cover the period from 1850-2000. Since aerosol-only simulation is not compulsory in CMIP5, these four runs are complements to other CMIP5 simulations conducted by Met Office using the HadGEM2-ES (vn 6.6).