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.

The Sodar/RASS device installed at Fussbach consisted of a DSDPA.90/64-Sodar and a DSDR3x7-1290MHz-RASS extension by METEK GmbH. It operated with an averaging period of 10 min. The minimum measurement height was 40 m and the maximum measurement height 700 m with a step width of 20 m in between.

The field experiments ALKOR 2000 (consisting of three cruises: ALKOR 4/2000, 6/2000, 10/2000) and ALKOR 2001 (4/2001, 6/2001, 10/2001) took place in the central Baltic Sea. The six cruises of the German Research Vessel Alkor with duration of about seven days each led to a point of the Baltic Sea which is most remote from the adjacent lands and additionally a grid point of regional climate model REMO. The ALKOR experiments as well as BASIS 1998 and BASIS 2001 are part of the research compound BALTIMOS (BALTic sea Integrated MOdel System). BALTIMOS in turn is part of the Baltic Sea Experiment (BALTEX). The overall objective of all eight field experiments (ALKOR and BASIS) was to collect a comprehensive data set suited to validate the coupled model system BALTIMOS for the Baltic Sea region. The observations mainly focus on: - the atmospheric boundary layer structure and processes and the air-sea-ice interaction over areas with inhomogeneous sea ice cover - the atmospheric boundary layer structure over open water under different synoptic conditions such as cold-air advection, warm-air advection or frontal passages. In addition to the published datasets several other measurements were performed during the experiment. Corresonding datasets will be published in the near future and are available on request. Details about all used platforms and sensors and all performed measurements are listed in the fieldreport. The following datasets are available on request: ground data at RV Alkor

Since the beginning of CALIPSO observations in June 2006 EARLINET has performed correlative measurements during nearby overpasses of the satellite at individual stations following a dedicated observational strategy. The EARLINET-CALIPSO correlative measurement plan considers the criteria established in the CALIPSO validation plan (http://calipsovalidation.hamptonu.edu). Participating EARLINET stations perform measurements, as close in time as possible and for a period of at least 30 min up to several hours, when CALIPSO overpasses their location within a horizontal radius of 100 km. Within the 16-day observational cycle of CALIPSO each station is overpassed within this distance 1-2 times during daytime (typically between 1100 and 1400 UTC) and 1-2 times during night time (typically between 0000 and 0300 UTC). Additional measurements are performed, mainly on a non-regular basis, when CALIPSO overpasses a neighboring station in order to study the horizontal variability of the aerosol distribution. The time schedule for correlative observations is calculated starting from the high-resolution ground-track data provided by NASA, and is updated and distributed to whole network weekly. The EARLINET-CALIPSO correlative dataset represents a statistically significant data set to be used for the validation and full exploitation of the CALIPSO mission, for studying the representativeness of cross sections along an orbit against network observations on a continental scale, and for supporting the continuous, harmonized observation of aerosol and clouds with remote-sensing techniques from space over long time periods.

KONTROL 1985 is part of research activities focused on organized convection phenomena as they are often manifested in organized cloud patterns like the well-known boundary layer cloud streets or open and closed cellular cloud structures. The experimental part of the investigations began with the experiment KonTur (Konvektion and Turbulenz) in September and October 1981. It continued with the experiments KONTROL in August 1984 and KONTROL in October 1985. All experiments took place over the German Bight in the southeastern part of the North Sea. The experimental concept based on the use of three fixed stations performing continuous aerological and surface observations and two aircraft conducting detailed observations during special periods. The stations were the island of Heligoland, the research vessel Valdivia and the research platform NORDSEE (54°42'N, 7°10'E). The aircraft were a FALCON-20 of DFVLR and a DO-28 Skyservant of the TU Braunschweig.

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 field experiments ALKOR 2000 (consisting of three cruises: ALKOR 4/2000, 6/2000, 10/2000) and ALKOR 2001 (4/2001, 6/2001, 10/2001) took place in the central Baltic Sea. The six cruises of the German Research Vessel Alkor with duration of about seven days each led to a point of the Baltic Sea which is most remote from the adjacent lands and additionally a grid point of regional climate model REMO. The ALKOR experiments as well as BASIS 1998 and BASIS 2001 are part of the research compound BALTIMOS (BALTic sea Integrated MOdel System). BALTIMOS in turn is part of the Baltic Sea Experiment (BALTEX). The overall objective of all eight field experiments (ALKOR and BASIS) was to collect a comprehensive data set suited to validate the coupled model system BALTIMOS for the Baltic Sea region. The observations mainly focus on: - the atmospheric boundary layer structure and processes and the air-sea-ice interaction over areas with inhomogeneous sea ice cover - the atmospheric boundary layer structure over open water under different synoptic conditions such as cold-air advection, warm-air advection or frontal passages. In addition to the published datasets several other measurements were performed during the experiment. Corresonding datasets will be published in the near future and are available on request. Details about all used platforms and sensors and all performed measurements are listed in the fieldreport. The following datasets are available on request: ground data at RV Alkor

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.

Aerosols originating from volcanic emissions have an impact on the climate: sulfate and ash particles from volcanic emissions reflect solar radiation, act as cloud condensation and ice nuclei, and modify the radiative properties and lifetime of clouds, and therefore influence the precipitation cycle. These volcanic particles can also have an impact on environmental conditions and could be very dangerous for aircraft in flight. In addition to the routine measurements, further EARLINET observations are devoted to monitor volcano eruptions. The EARLINET volcanic dataset includes extended observations related to two different volcanoes in Europe Mt. Etna (2001 and 2002 eruptions), and the Eyjafjallajökull volcano in Iceland (April - May 2010 eruption). This dataset includes also recent events of volcanic eruptions in the North Pacific region (2008-2010) that emitted sulfuric acid droplets into the upper troposphere - lower stratosphere (UTLS) height region of the northern hemisphere. The EARLINET volcanic observations in the UTLS are complemented by the long-term stratospheric aerosol observations collected in the Stratosphere category.

This collection contains all measurements that have been performed in the frame of the EARLINET project during the period April 2000 - December 2015. 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', 'ForestFires', '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.