An International team of researchers at UCC is building a high-tech instrument for the CARIBIC project to collect airborne measurements of greenhouse gases, trace species and aerosol in the upper troposphere, at typical altitudes of 10 to 12 km.

CARIBIC is a large scale European programme with the aim of studying global climate change. A container with 15 existing instruments is currently flying on board a commercial Lufthansa aircraft since 2005 and has already completed more than 330 flights across the globe.

There are currently 7 researchers from 3 world-class Institutes working on the new instrument: Prof. Andy Ruth, Dr. Marc Goulette, and Dr. Hemanth Dinesan from UCC, Dr Steven Brown, Bill Dubé and Dr. Gerhard Hübler from NOAA (USA), and the CARIBIC coordinatorDr. Andreas Zahn from KIT (Germany).

The instrument consists of 4 optical cavities using High Reflective (HR) mirrors, in which the sample air from outside the plane is injected in. Two diode lasers send a signal (light) through these cavities and are used to measure the concentrations of different essential gas species. The light coming out of the cavities is collected by 4 photomultiplier (PMT) tubes, and the signal is sent to the Data Acquisition system (DAQ) before reaching the computer. The device is a Cavity-Enhanced instrument based on the CRDS approach.

The full instrument is expected to deliver data from the summer 2018, for about 18 months.


The host aircraft is an Airbus A340-600 which can accommodate up to 380 passengers. CARIBIC travels in the cargo hold of the plane once or twice per month.




A dedicated inlet system allows the air from outside of the plane to enter the inside of the container.




CARIBIC's assembly hall at the KIT Institute. CARIBIC instrument highlighted with yellow arrow.




CARIBIC is part of an even larger European initiative called IAGOS.




Design of the instrument (Sept. 2015). Top: optical cage, aerosol filters, and temperature controllers.           Middle: Data Acquisition system. Bottom: Pump, gas system, and electrical box.


Click for larger image of CARIBIC status



Status of the instrument (November 2017). The instrument is presently undergoing testing at NOAA. Click here for larger images of instrument from all angles.


Further reading:

[1] C. Brenninkmeijer et al., Civil Aircraft for the regular investigation of the atmosphere based on an instrumented container: The new CARIBIC system, Atmos. Chem. Phys. 7 (2007) 4953-4976.
[2] S. Brown, J. Stutz, Nighttime radical observations and chemistry, Chem. Soc. Rev., 2012, 41, 6405-6447
[3] W. Dubé et al., Aircraft instrument for simultaneous, in situ measurement of NO3 and N2O5 via pulsed cavity ring-down spectroscopy, Rev. Sci. Instrum., 77, 034101, 2006
[4] H. Fuchs et al., Determination of Inlet Transmission and Conversion Efficiencies for in Situ Measurements of the Nocturnal Nitrogen Oxides, NO3, N2O5 and NO2, via Pulsed Cavity Ring-Down Spectroscopy, Anal. Chem., 80, 6010-6017, 2008
[5] N. Wagner et al., Diode laser-based cavity ring-down instrument for NO3, N2O5, NO, NO2 and O3 from aircraft, Atmos. Meas. Tech., 4, 1227-1240, 2011
[6] M. Wheeler et al., Cavity ring-down spectroscopy, J. Chem. Soc., Faraday Trans., 1998, 94(3), 337-351

Conference presentations (show)

Last updated:

1 February 2018



CARIBIC Science Foundation Ireland KIT NOAA Marie Curie Actions FP6