The research aircraft DO-128, call sign D-IBUF, of the IFF (TU Braunschweig) measures numerous meteorological and chemical variables to get a better understanding of the atmospheric processes which cause the development of precipitation. The aircraft starts from the Baden Airpark and flys among different flight pattern which are described in the flight protocols. The meteorological variables are static pressure and dynamic pressure at the nose boom, surface temperature, humidity mixing ratio by a lyman-alpha sensor, dewpoint temperature by a dewpoint-mirror, relative humidity by an aerodata-humicap, air temperature by a PT-100 sensor, vertical and horizontal wind components by a five-hole probe and GPS, turbulence (100 Hz), shortwave (pyranometer) and longwave (pyrgeometer) radiance in upper und lower half space. The chemical variables are mole fractions of ozone, carbon dioxide, carbon monoxide, nitrogen dioxide, nitrogen monoxide and nitric oxides (NOx). There are also a few variables for the position and the velocity of the aircraft stored in the data file. Additionally to the measurements by the aircraft, up to 30 drop-sondes can be dropped out of the aircraft. By using these sondes, vertical profiles of temperature, pressure, humidity and wind can be detected (see also the meta data describing the drop-sonde data). Special events are also marked in the data files by the event counter (e.g. dropping times of the drop-sondes, marks concerning the flight patterns etc.). The specific action or flight manoeuvre indicated by the event_number can be identified in the flight protocol.

Several meteorological parameteres were measured at different stations run by FZK/IMK-TRO. Depending on the individual site i.e. wind direction, wind speed, global radiation, reflected irradiance, atmospheric longwave radiation, terrestric longwave radiation, surface temperature, precipitation, air pressure, soil heat flux, relative humidity. The respective set of parameters is described in the meta data of each station.

The Soundings were usually performed during the daytime of IOPs at two fixed locations. Scheduled launching times were at 05, 08, 11, 14, 17 and 20 UTC. Radiosounding at Burnhaupt le Bas, France: Sondes of the type DFM-06 manufactured by the Company GRAW (http://graw.de) have been used. Radiosounding at FZK, Karlsruhe, Germany Sondes of the type DFM-97 manufactured by GRAW (http://graw.de) have been used. From 26 July at 5:02 DFM-06 sondes of the same company have been used. On 25 July at 11:08 there was a test run of a DFM-06 sonde.

The geographical distribution of the EARLINET stations is particularly suitable for dust observation, with stations located all around the Mediterranean (from the Iberian Peninsula in the West to the Greece and Bulgaria and Romania in the East) and in the center of the Mediterranean (Italian stations) where dust intrusions are frequent, and with several stations in the central Europe where dust penetrates occasionally. A suitable observing methodology has been established within the network, based on Saharan dust alerts distributed to all EARLINET stations. The dust alert is based on the operational outputs (aerosol dust load) of the DREAM (Dust REgional Atmospheric Model), and the Skiron models. The alerts are diffused 24 to 36 hours prior to the arrival of dust aerosols over the EARLINET sites. Runs of measurements longer than 3-hour observations, typical for the EARLINET climatological measurements are performed at the EARLINET stations in order to investigate the temporal evolution of the dust events. All aerosol backscatter and extinction profiles related to observations of Saharan dust layers are collected in the "Saharan dust" category of the EARLINET database.

Reflectivity and radial velocity of Karlsruhe C-Band Doppler Radar located at Forschungszentrum Karlsruhe. Volume data in polar coordinates are delivered. Two scans have been performed: 1. 14 Elevation volume scan of reflectivity and radial velocity starting at 0.4 deg elevation up to 30 deg elevation, 120 km range, 500 m resolution, dual PRF (pulse repetition frequency; 1153 Hz/864 Hz): reflectivity and radial velocity. 2. 14 Elevation volume scan as 1, but only single PRF: reflectivity. The data is provided in two different data sets: reflectivity (ca. every 5 min; data from both scan modi) and radial_velocity (every 10 min; data from 1st scan mode).

Surface layer scintillometer data derived from a Optical Energy Balance Measurement System OEBMS1 with a Scintillometer SLS20 system by Scintec AG at station UV1EG (Deckenpfronn). The system operated at a measurement height of 1.75 m and with a path length of 117 m over the target land use type meadow.

The Convection and Turbulence Experiment (KonTur) was conducted in the southeastern part of the North Sea from 14 September to 21 October 1981 (with a break from 4 to 8 October). KONTUR aimed at two main scientific objectives. First, to observe the formation and time variation of regularly organized convection in the lower troposphere as a function of the mean atmospheric flow and the lower boundary condition and to quantify the dependence of the vertical transports of momentum, heat and water mass on various scales of motion in order to test existing convection models and to provide an observational background for the extension of theoretical concepts. Second goal was to determine the mean and turbulent quantities within the marine atmospheric boundary layer (ABL), including the large scale horizontal and vertical advection of momentum, heat and water vapour, cloud microphysics and the radiation field, in order to assemble a comprehensive data set for boundary layer modelling with first and second order closure methods. The experiment covered an area in the southeastern part of the North Sea (German Bight), roughly between latitudes 53¿N and 56¿N and longitudes 6¿E and 9¿E. Both the convection and the turbulence programme made use of the same experimental tools which can be subdivided in the following four groups: the central station occupied by the research vessel Meteor, the aerological network (Borkumriff, RV Meteor, RV Gauss/Poseidon, Research Platform Nordsee, Elbe 1), two aircraft (Hercules C-130, Falcon 20) and supporting observations, such as satellite images, cloud photography, surface and upper air large-scale fields from routine data. KONTUR 1981 was followed by the experiments KONTROL 1984 and KONTROL 1985.

EARLINET climatological lidar observations are performed on a regular schedule of one daytime measurement per week around noon (on Monday), when the boundary layer is usually well developed, and two night-time measurements per week (on Monday and Thursday), with low background light, in order to perform Raman extinction measurements. This regular schedule for observations minimizes the bias in the dataset possibly related to specific measurement conditions. The resulting dataset is used to obtain unbiased data for climatological studies. This dataset contains profiles of aerosol extinction, backscatter and lidar ratio. Several aerosol extinction/backscatter datasets can be present for the same climatological measurement in order to provide profiles either with a better temporal resolution or with an extended height range by using a larger temporal average. This is by far the largest ground based dataset on the aerosol vertical distribution, and it is the only one which is collected systematically and is covering a whole continent.

This collection contains all measurements that have been performed in the frame of the EARLINET project during the period April 2000 - December 2010. Some of these measurements are also part of the collections 'Calipso', 'Climatology', 'SaharanDust' or 'VolcanicEruption'. In addition this collection also contains measurements from the categories 'Cirrus', 'DiurnalCycles', 'ForrestFires', 'Photosmog', 'RuralUrban', and 'Stratosphere'. This collection also contains measurements not devoted to any of the above categories. More information about these categories and the contributing stations can be found in the file 'EARLINET_general_introduction.pdf' accompanying this dataset.

The energy balance station run by University of Bonn measured high-frequency (10 Hz) eddy-covariance raw data with a CSAT3 (Campbell Scientific, Inc.) sonic anemometer and a LI-7500 (LI-COR Biosciences) hygrometer above the target land use type meadow. The measuring set-up was continuously running during the entire COPS measurement period in order to provide a complete time series of the turbulent fluxes of momentum, sensible and latent heat as well as carbon dioxide. Post-processing was performed using the software package TK2 (developed by the Department of Micrometeorology, University of Bayreuth) which produces quality assured turbulent flux data with an averaging interval of 30 min. The documentation and instruction manual of TK2 (see entry cops_nebt_ubt_info_1) and additional references about the applied flux corrections and post-field data quality control (see entry cops_nebt_ubt_info_2) as well as a document about the general handling of the flux data can be found in supplementary pdf-files within the energy balance and turbulence network (NEBT) experiment of the data base. The turbulent flux data in this data set are flagged according to their quality and checked for an impact of possible internal boundary layers. Additionally, the flux contribution from the target land use type intended to be observed to the total flux measured was calculated applying footprint modeling. Information and references about the internal boundary layer evaluation procedure and the footprint analysis are also given in additional info pdf-files. Pictures of the footprint climatology of the station as related to the land use and to the spatial distribution of the quality flags are included in the corresponding additional info pdf-file.