Soil Moisture data (version 04.7) from the European Space Agency's (ESA) Soil Moisture Climate Change Initiative (CCI) project. This dataset collection contains three surface soil moisture datasets, alongside ancilliary data products. The ACTIVE and PASSIVE products have been created by fusing satellite scatterometer and radiometer soil moisture products respectively. In the case of the ACTIVE product, these have been derived from the AMI-WS and ASCAT satellite instruments and for the PASSIVE product from the satellite instruments SMMR, SSM/I, TMI, AMSR-E, WindSat, AMSR2 and SMOS. The COMBINED product is generated from the Level 2 active and passive instruments.. The homogenized and merged products present a global coverage of surface soil moisture at a spatial resolution of 0.25 degrees. The products are provided as global daily images, in NetCDF-4 classic file format, the PASSIVE and COMBINED products covering the period (yyyy-mm-dd) 1978-11-01 to 2019-12-31 and the ACTIVE product covering 1991-08-05 to 2019-12-31. The soil moisture data for the PASSIVE and the COMBINED product are provided in volumetric units [m3 m-3], while the ACTIVE soil moisture data are expressed in percent of saturation [%]. For information regarding the theoretical and algorithmic base of the datasets, please see the Algorithm Theoretical Baseline Document (ATBD). Other additional documentation and information documentation relating to the datasets can also be found on the CCI Soil Moisture project web site or in the Product Specification Document. The data set should be cited using the all of the following references: 1. Gruber, A., Scanlon, T., van der Schalie, R., Wagner, W., and Dorigo, W. (2019). Evolution of the ESA CCI Soil Moisture climate data records and their underlying merging methodology, Earth Syst. Sci. Data, 11, 717–739, https://doi.org/10.5194/essd-11-717-2019 2. Dorigo, W.A., Wagner, W., Albergel, C., Albrecht, F., Balsamo, G., Brocca, L., Chung, D., Ertl, M., Forkel, M., Gruber, A., Haas, E., Hamer, D. P. Hirschi, M., Ikonen, J., De Jeu, R. Kidd, R. Lahoz, W., Liu, Y.Y., Miralles, D., Lecomte, P. (2017). ESA CCI Soil Moisture for improved Earth system understanding: State-of-the art and future directions. In Remote Sensing of Environment, 2017, ISSN 0034-4257, https://doi.org/10.1016/j.rse.2017.07.001 3. Gruber, A., Dorigo, W. A., Crow, W., Wagner W. (2017). Triple Collocation-Based Merging of Satellite Soil Moisture Retrievals. IEEE Transactions on Geoscience and Remote Sensing. PP. 1-13. 10.1109/TGRS.2017.2734070

The ESA Sea State CCI project has produced global multi-sensor time-series of satellite altimeter significant wave height data with a particular focus for use in climate studies. A number of products are available: a Level 2P (L2P) along-track dataset, a Level 3 (L3) daily merged along-track dataset, and a L4 montly gridded product. This first version of the Sea State CCI products is inherited from the GlobWave project, building on experience and existing outputs. It extends and improves the GlobWave products ,which were a post-processing over existing L2 altimeter agency products with additional filtering, corrections and variables. A major improvement consists in a new denoised sea surface height variable using Empirical Mode Decomposition, which was used as input to these monthly statistical fields. The altimeter data used in the Sea State CCI dataset v1.1 come from multiple satellite missions spanning from 1991 to 2018 (ERS-1, ERS-2, Topex, Envisat, GFO, CryoSat-2, Jason-1, Jason-2, Jason-3, SARAL). Many altimeters are bi-frequency (Ku-C or Ku-S) and only measurements in Ku band were used, for consistency reasons, being available on each altimeter but SARAL (Ka band).

This dataset collection contains data collected from the Microbiology-Ocean-Cloud Coupling in the High Arctic (MOCCHA) project. MOCCHA aimed to study aerosol processes, the contribution of marine microbiology to their formation and properties, and their impact on the life cycle of low-lewel clouds in the central Arctic as part of the Arctic Ocean 2018 (AO2018) expedition. AO2018 took place between 1 August and 21 September 2018, departing from and returning to Longyearbyen. The expedition was centered around a 4-week long intensive observation period, where e icebreaker Oden was moored to an ice flow and drifted passively with the ice.

This dataset collection contains the results of the analysis conducted on PM2.5 (particulate matter) samples by the Si-SOA project. The PM2.5 samples were collected in the Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences, China during August 2018 and January 2019 by the Silicon-containing secondary organic aerosols in ambient air (Si-SOA) project. The PM2.5 samples were taken from ambient air at the height of 8m and subjected to a series of analytical techniques, and the data collection is comprised of the following results. - The concentration of water-soluble Silicon/water-soluble organic Silicon/water-soluble inorganic Silicon in PM2.5 samples from Ultraviolet-Visible Spectrophotometry - The concentration of specific ions in PM2.5 samples from Ion Chromatography - The concentration of water-soluble Silicon in PM2.5 samples from Coupled Plasma - Optical Emission Spectrometry (ICP-OES) - The concentration of water-soluble elements in PM2.5 samples from Inductively Coupled Plasma Mass Spectrometry (ICP-MS) - The concentration of elements in PM2.5 samples from X-ray Fluorescence Spectrometry These data support the study of atmospheric processes in relation to fine Silicon-containing particles, which may contribute to the formation of haze and atmospheric pollution.

This dataset collection contains in situ atmospheric and aerosol measurements collected at Summit Station, Greenland. These data were collected as part of the joint Natural Environmental Research Council (NERC) and US National Science Foundation (NSF) -funded Integrated Characterisation of Energy, Clouds, Atmospheric state, and Precipitation at Summit - Aerosol Cloud Experiment (ICECAPS-ACE) project. Since 2010, the ICECAPS project has been monitoring cloud-atmosphere-energy interactions at Summit Station, in the centre of the Greenland Ice Sheet (GrIS), using a comprehensive suite of ground-based remote sensing instruments and twice daily radiosonde profiles. In 2018, the Aerosol Cloud Experiment (ACE) expansion of ICECAPS saw the addition of a new series of instruments to measure surface aerosol concentrations and turbulent heat fluxes over the ice sheet. Combined with the original ICECAPS instrumentation, the ACE instruments allow for the study of cloud-aerosol-energy interactions over the central GrIS. This dataset collection contains the measurements collected as part of the ACE component of ICECAPS-ACE, which includes the following: 1) Surface-temperature-profile: A near surface temperature profile from four temperature/ humidity sensors distributed on the 15 m tower at Summit. 2) Surface-moisture-profile: A near surface moisture profile from four temperature/ humidity sensors distributed on the 15 m tower at Summit. 3) Surface-winds-profile: A near surface wind profile from four sonic anemometers distributed on the 15 m tower at Summit. 4) Snow-height: The distance to the snow surface from the lowest level of instruments on the 15 m tower at Summit, detected by a sonic-ranging sensor. 5) Skin-temperature: The brightness temperature of the snow surface as detected by an infrared radiation thermometer. 6) Aerosol-concentration: The concentration of condensation nuclei (> 5nm diameter) measured at the surface using a Condensation Particle Counter. 7) Aerosol-size-distribution: The size-resolved concentration of surface aerosol particles between 0.25 and 6.5 um in diameter measured using an Optical Particle Counter. 8) Flux-components: High resolution temperature, humidity and wind fluctuations that can be used to estimate turbulent fluxes using eddy covariance, located at two levels on the 15 m tower at Summit. 9) Flux-estimates: Estimates of turbulent heat and momentum fluxes by applying the eddy covariance technique to flux-components. Other ICECAPS data are available here: https://psl.noaa.gov/arctic/observatories/summit/

This collection contains version 4.2 datasets produced by the Ocean Colour project of the ESA Climate Change Inititative (CCI). The Ocean Colour CCI is producing long-term multi-sensor time-series of satellite ocean-colour data with a particular focus for use in climate studies. Data products being produced include: phytoplankton chlorophyll-a concentration; remote-sensing reflectance at six wavelengths; total absorption and backscattering coefficients; phytoplankton absorption coefficient and absorption coefficients for dissolved and detrital material; and the diffuse attenuation coefficient for downwelling irradiance for light of wavelength 490 nm. Information on uncertainties is also provided. This dataset collection refers to the Version 4.2 data products held in the CEDA archive covering the period 1997-2019. Links to the individual datasets that make up this collection are given in the record below.

European circulation indices calculated from the UKCP Global (60km) climate projections from 1900-2100 under RCP8.5 produced by the Met Office in 2018. These indices represent large scale circulation variability and they include: (i) the daily latitude and strength of the Atlantic Jet Stream; (ii) the daily ‘weather type’ (1-8 or 1-30) which is based on a classification scheme for the daily large scale synoptic situation; (iii) the average winter Atlantic pressure gradient between Iceland and Gibraltar representing the winter North Atlantic Oscillation (NAO). The indices are available for each member in the set of 28 global projections, which is a combination of 15 coupled model simulations produced by the Met Office Hadley Centre, and 13 coupled simulations from CMIP5 contributed by different climate modelling centres. The indices included are either daily or monthly. Although they are based on data from the global runs on an N216 (60km) grid, these indices have a single value per timestep and have no latitude-longitude dimension.

This dataset contains Global Precipitation Measurements (GPM) Integrated Multi-satellitE Retrievals (IMERG) v5 and v6. The Global Precipitation Measurement (GPM) mission is an international network of satellites that provide the next-generation global observations of rain and snow.

This collection of data forms the Permafrost Climate Research Data Package (CRDP v1), which comprises the Version 2.0 Permafrost data products from the European Space Agency's (ESA) Climate Change Initiative (CCI) Permafrost project. Data products include Ground Temperature, Active Layer Thickness and Permafrost Extent for the Northern Hemisphere (north of 30°) for the period 1997-2018. They are derived from a thermal model driven and constrained by satellite data. Gridded products are released in annual files, covering the start to the end of the Julian year. This corresponds to average annual ground temperatures, as well as the maximum depth of seasonal thaw, which corresponds to the active layer thickness.

The UK DECC (Deriving Emissions linked to Climate Change) Network consists of five sites in the UK and Ireland measuring greenhouse and ozone-depleting gases. The four UK-based sites (Ridge Hill, Herefordshire; Tacolneston, Norfolk; Bilsdale, North Yorkshire; and Heathfield, East Sussex) sample air from elevated inlets on tall telecommunications towers. Mace Head, situated on the west coast of Ireland, samples from an inlet 10 meters above ground level and is ideally situated to intercept baseline air from the North Atlantic Ocean. This collection contains high frequency measurements of all major greenhouse gases made at the four UK stations, including carbon dioxide, methane, nitrous oxide and sulfur hexafluoride. Mace Head data are available separately - see link in documentation. Data from the UK DECC network are used to assess atmospheric trends and quantify UK emissions, and feeds into other international research programs, including the Integrated Carbon Observation System (ICOS) and Advanced Global Atmospheric Gases Experiment (AGAGE) networks. This work is funded by the UK Department for Business Energy and Industrial Strategy (BEIS) under contract 1537/06/2018 to the University of Bristol and through the National Measurement System at the National Physical Laboratory.