WCCAP - CAIS-ECAC

During the year the WCCAP offers different ACTRIS- and GAW-Workshops for the National Facilities (NF) and Global Atmospheric Watch (GAW) stations. The workshops are split over the whole year and contains mobility particle size spectrometer (MPSS), condensation partice counter (CPC), aerodynamic particle size spectrometer (APSS), optical instruments (AP,IN,EM) and cloud condensation nuclei counter (CCNC). The workshop schedule is frequently updated and shows the invited participants during the workshops. In the second half of the actual year we announce the workshop schedule of the upcoming year. The following overview shows the planed workshop weeks during the year.

For more details, please click on the calendar.

Mobility Particle Size Spectrometer (MPSS) and Condensation Particle Counter (CPC)

In this workshop, the candidate MPSS is intercompared against the Reference MPSS system in two settings: settings at the home institute and in the laboratory. Two main calibrations are done: (1) calibration of the sizing efficiency with 203 nm PSL particles and (2) calibration of the HV power supply. The counting efficiency of the CPC for different particle diameters is determined using size-selected silver particles and compared against a Reference Electrometer. Aside from troubleshooting and maintenance of the instruments, capacity building is also done in these workshop through theory discussions, operation of instruments, and data evaluation training.  

Kay Weinhold

email: weinhold[at]tropos.de

Mobile: +49 160 92 28 59 39

Office: +49 34127177308

Office room: 201

Aerodynamic Particle Size Spectrometer (APSS)

In this workshop, the candidate APSS is intercompared with another APSS unit using generated particles and ambient air. A sizing check is also done with a mixture of PSL particles of different sizes.

Sascha Pfeifer

email: pfeifer[at]tropos.de

Optical Instruments: Absorption Photometer (AP), Integrating Nephelometer (IN), Extinction Monitor (EM)

In this workshop, the candidate devices (integrating nephelometers, absorption photometers or extinctions cells) are compared against a setup of optical reference instruments, both in the initial state and after maintenance. Various test aerosols, especially ammonium sulphate and synthetically generated black carbon using Mini-CAST, are used for this purpose. In addition, for nephelometers, CO2 based span checks are performed.

Absorption photometers are tested against an absorption reference based on "extinction minus scattering approach".

If necessary, the devices are cleaned and re-calibrated depending on the device type.

Finally, the test procedure is repeated.

Sascha Pfeifer

email: pfeifer[at]tropos.de

Cloud Condensation Nuclei Counter (CCNC)

In this workshop, the candidate CCNc is inter-compared against the Reference CCNc in two settings: flow and supersaturation settings at the home institute and settings after calibration. Two calibrations are done: (1) flow calibration of aerosol and sheath air flow and (2) calibration of the instrument’s supersaturation versus deltaT. Aside from troubleshooting and maintenance of the instruments, capacity building is also done in these workshop through theory discussions, operation of instruments, and data evaluation training.

Silvia Henning

email: henning[at]tropos.de

Office: +49 341 2717 7321

On-Site Intercomparisons and Audits

This is another dimension of the ECAC activities where reference instruments (MPSS & CPC) are brought to the monitoring stations for inter-comparisons under the real-world, on-site conditions. This could also provide an avenue for capacity building of the personnel suited for the specifics of their monitoring station. In addition, these stations are audited according to the requirements of the WMO-GAW.

Kay Weinhold

email: weinhold[at]tropos.de

Mobile: +49 160 92 28 59 39

Office: +49 34127177308

Office room: 201

Round Robin Tours

The Round-Robin tours are specifically designed for the on-site intercomparison between the particle size spectrometer and reference CPC. Five reference CPCs are sent to different participating institutes/stations simultaneously where they will perform the intercomparisons themselves. Upon completion, the CPCs are sent to the next participant until it makes a complete round. After one round, the CPCs are sent back to WCCAP for quality assurance.

Kay Weinhold

email: weinhold[at]tropos.de

Mobile: +49 160 92 28 59 39

Office: +49 34127177308

Office room: 201