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.

KONTROL 1984 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 two fixed stations performing continuous aerological and surface observations and two aircraft conducting detailed observations during special periods. The stations were 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.

The geographical distribution of the EARLINET stations is particularlysuitable 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 SDS-WAS (Sand and Dust Storm- Warning and Advisory System of WMO), 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.

The positions of the meteorological towers (IMKMT1 to IMKMT4) are identical with the positions of the launching sites of the drop-up-sondes (IMKRS1 to IMKRS5). There have been no more than 4 teams operating on each IOP. For detailed information about the sites (including a map) and operating days see supplement pdf-file (cops_rsdu_imk_info_1). The parameters are: air_pressure: measured at about 1.8 m GND by a barometric pressure sensor that has a gill pressure port, 60s mean. air_temperature_at_1.8m: measured at about 1.8 m GND by a HYGROMER meteorology probe MP 400a, 60s mean. relative_humidity_at_1.8m: measured at about 1.8 m GND by a HYGROMER meteorology probe MP 400a, 60s mean. precipitation_amount: measured by a tipping bucket rain gauge (catchment area: 200 cm**2), 60s accumulated. wind_speed_at_4.5m, wind_from_direction_at_4.5m, virtual_temperature_at_4.5m: measured at about 4.5 m by a Young 3-D Sonic Anemometer, 60s mean.

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.

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 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.

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 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.

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.

Dropsondes (mobile radiosondes) were launched by 5 mobile radiosonde teams. The launching sites were different from IOP to IOP. The positions are identical with the positions of the meteorological towers (imkmt1 to imkmt4). There have been no more than 4 teams operational on each IOP. The dropsondes are radiosonde-like systems. The maximum height is 12050 m above MSL. At this height, the sondes are separated from the balloon and then glide to the ground. Drop points are up to 70 kilometres apart from launching sites. For detailed information about the sites see supplement file and map.