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JOYCE is a unique site for cloud observation. Although we encounter clouds daily, their spatial structure as well as their interior (the so-called microphysics) are subject to ongoing research. When, where, and under which atmospheric conditions cloud formation occurs is a major challenge for current weather and climate prediction models. However, it is the very presence of clouds which determines whether precipitation can form and whether the Earth's surface warms or cools. Be sure to watch our You-Tube-Video "How does a cloud form?"

JOYCE aims at investigating the processes leading to cloud formation and cloud evolution. To this end, various instruments are currently set up at the Research Centre Jülich, in order to continuously monitor water vapour, clouds, and precipitation over many years. Only such observations will eventually make it possible to improve the prediction of clouds by weather and climate models.

The JOYCE instruments enable to determine the properties of clouds from the ground, i.e., without having to fly through them. By transmitting and receiving radiation at various wave lengths (optical, infra-red, microwave), information on spatial extent, water content, drop size, etc. can be obtained. The most important JOYCE instruments can be rotated in all spatial directions, thereby gaining an impression of the three dimensional structure of clouds.

JOYCE is embedded in the DFG Sonderforschungsbereich Transregio32 Patterns in Soil-Vegetation-Atmosphere Systems - Monitoring, modelling and data assimilation of the Universities of Aachen, Bonn, Köln, and the Research Centre Jülich. Overall goal is an improved understanding of the interactions between soil, vegetation, and atmosphere through spatially and temporally highly resolved measurements and through modelling of the crucial processes.

Nationally, JOYCE is a registered DFG Research Infrastructure and has recently (beginning of 2016) been funded as a DFG Core Facility ("Gerätezentrum") in order to professionally manage user access to JOYCE instruments, observation data and scientific expertise. More information will be available soon via this website.

Internationally, JOYCE is a Cloudnet observatory embedded within the European Horizon2020 Research Infrastructure ACTRIS-2. In March 2016 the European Strategy Forum for Research Infrastructures (ESFRI) officially adopted ACTRIS (Aerosols, Clouds, and Trace gases Research Infrastructure) on its updated research infrastructure roadmap.

JOYCE Measurements

Current and past JOYCE measurements can be found in our quicklook browser. The instruments are described below.

JOYCE Instruments

The majority of the JOYCE instruments is positioned on the roof of the Institut für Energie und Klimaforschung (IEK-8) at Forschungszentrum Jülich (50°54'30.77'' N, 6°24'48.73" E, 111 m MSL). The core instruments of JOYCE can be found below. Further instrumentation on the same observation platform includes a Pluvio rain gauge, a meteorological station (temperature, pressure, wind, humidity) and a MAX-DOAS system for trace gases and aerosol operated by IEK-8.

Atmospheric Emitted Radiance Interferometer AERI

 
  • measures highly spectrally resolved infrared radiation
  • derivation of cloud particle size, cloud optical depth, temperature and humidity profile
  • details and measurement time series can be found here
 
Doppler Lidar
 
  • transmits and receives light pulses in the mear infrared spectral region
  • retrieves the wind vector (wind direction and velocity) up to 2-3 km height
  • details and measurement time series can be found here
 
Ceilometer CHM15k
 
  • trasmits and receives light pulses in the near infrared up to 15 km height
  • derivation of cloud base, detection of boundary layer height and aerosol layers
  • details and measurement time series can be found here
 
Ceilometer CT25k
 
  • trasmits and receives light pulses in the near infrared up to 7.5 km height
  • derivation of cloud base, detection of boundary layer height and aerosol layers
  • details and measurement time series can be found here
 

 
Cloud Radar JOYRAD-35
 
  • transmits and receives pulses of microwave radiation (35 GHz) in arbitrary direction
  • derivation of cloud thickness and cloud structure
  • details and measurement time series can be found here
 
Cloud Radar JOYRAD-94
  • transmits and receives continuously at 94 GHz pointing zenith
  • derivation and observation of cloud structure and micro-physical processes  
  • details and measurement time series can be found here
Microwave Radiometer HATPRO & IR Pyrometer
 
  • measures microwave radiation emitted by the atmosphere itself (HATPRO)
  • measures atmospheric broadband IR radiation (pyrometer)
  • derivation of cloud liquid water path, temperature profile, humidity profile, cloud base temperature
  • details and measurement time series can be found here
 
Micro Rain Radar MRR
 
  • measures vertical profiles of the Doppler spectrum of precipitation
  • derivation of vertical profiles of drop size distribution and from this precipitation rates
  • details and measurement time series can be found here
 
Multi-Filter Rotating Shadow Band Radiometer (MFRSR)
  • measures solar radiation at different wavelengths
  • derivation of aerosol optical depth and information on aerosol particle size as well as properties of liquid clouds (cloud optical depth, effective radius)
  • details and measurement time series can be found here
Precipitation Sensor Disdrometer
 
  • Parsivel (optical): measures size and fall velocity of rain drops at the surface
  • derivation of drop size distribution and from this the surface precipitation rate
  • details and measurement time series can be found here
  • in addition: Pluvio precipitation gauge (click here)
 
Radiation Sensors
 
  • pyranometer for downwelling solar radiation (direct and diffuse)
  • pyrgeometer for downwelling thermal radiation
  • actinic flux measurments (UV) for derivation of photolysis-frequencies
  • details and measurement time series can be found here
 
Sun Photometer CIMEL
 
  • sun photometer for measuring aerosol optical depth
  • details and measurement time series can be found here
 
Tower for Meteorological Measurements(120 m)
 
  • temperature, humidity and wind measurements at 8 heights
  • upwelling and downwelling flux density measurements at 2 heights
  • precipitation measurements at the surface
  • details and measurement time series can be found here
 
Total Sky Imager TSI
 
  • takes picture of the total upper hemisphere
  • provides a per-pixel classification of optically thin and thick clouds
  • derivation of cloud cover
  • details and measurement time series can be found here