WCCOS

Since 1996 the Environmental Simulation Facility (ESF) at Forschungszentrum Juelich established as World Calibration Center for Ozone Sondes (WCCOS) of the WMO: a facility for quality assurance and quality control (QA/QC) of ozone sondes used in the global ozonesonde network on ozone sonde precision, accuracy and long term stability.

The controlled environment plus the fact that the ozone sonde measurements can be compared to an accurate UV-Photometer as reference allows to conduct experiments that are designed to address questions which arise from field operation and data analysis to detect long term changes of ozone in the troposphere and stratosphere.

Since 1996 the Jülich Ozone Sonde Intercomparison Experiment (JOSIE) is established to investigate the performance of ozonesondes in terms of precision, uncertainty and bias effects. Hereby, pressure, temperature and ozone concentration can be varied to simulate under quasi realistic atmospheric conditions an ozonesonde balloon ascend from the surface until its burst altitude at 33-35 km altitude. Thereby different temperature and ozone profiles can be simulated