The MAGIC2020 campaign

The MAGIC2020 campaign takes place between 9-16 September 2020. It involves 5 laboratories (LMD, GSMA, LOA, LERMA, LSCE), CNES and SAFIRE.

SAFIRE Falcon20 performs profiles at 2 locations: Aire-sur-l’Adour and Toulouse-Francazal, in order to get vertical profiles of CO2, CH4 and CO, as well as of temperature and humidity. Meteorological balloons equipped with AirCore air samplers and Amulse laser-diode spectrometers are launched at Aire-sur-l’Adour CNES station. Finally, 4 portable Fourier Transform Spectrometers (three EM27/SUN and one CHRIS) are deployed on the ground to provide total columns of trace gases.

A specific objective for this campaign is the validation of NASA OCO-2 and ESA TROPOMI/Sentinel-5P satellites that provide total columns of CO2 and CH4, respectively. Ground-based spectrometers are located along the satellites’ paths and SAFIRE/Falcon20 flies under the satellites.

This campaign is funded by CNES and CNRS.


Campaign Log Book

Day 1 – 9 September 2020

The teams arrive at Aire-sur-l’Adour and Toulouse-Francazal for the final preparation of the instruments and of the flights. Weather forecast is good for the next days: sunny days (essential for satellite and ground-based Fourier Transform Spectrometers), low wind, good balloon trajectories. The campaign is a GO!

Day 2 – 10 September 2020

Two AirCore are launched under meteorological ballons from Aire-sur-l’Adour CNES facilities at 9:00 and 10:00 UTC to be colocated with European Metop-C/IASI overpass at 10:16 UTC.

Meanwhile, 3 EM27/SUN spectrometers are depoyed alongside each other at the station. Fortunately, clouds go away by the end of the morning.

First AirCore launch from Aire-sur-l’Adour during  MAGIC2020 (c) A. Guedj, 2020

Authorization from flight authorities are granted for SAFIRE/Falcon20 flight on Sept. 11th. It is a green light for next day!

Day 3 – 11 September 2020

All measurement devices are deployed today: 5 balloon launches from Aire-sur-l’Adour (3 AirCores and 2 Amulse), 3 EM27/SUN, 1 CHRIS… and 2 Falcon20 flights!

The  objective of the day is to validate ESA TROPOMI/Sentinel-5P total columns of CH4 and to study the variation of the gas distribution between Aire-sur-l’Adour and Toulouse. To that end, 3 ground-spectrometers are deployed under the track of Sentinel-5P and SAFIRE/Falcon20 makes two successive flights : first, two up-down spirals at Aire-sur-l’Adour; second, an along-track flight.

Measurements performed during MAGIC2020 on Sept. 11th. SAFIRE/Falcon20 tracks and altitudes are indicated, as well as the locations of: the release of 5 dropdsondes; the 4 ground-based spectrometers (3 EM27/SUN and CHRIS); and the landing site of AirCore/Amulse launched under meteorological balloons from Aire-sur-l’Adour.
SAFIRE/Falcon20. First low overpass at Aire-sur-l’Adour (c) A. Guedj
Preparation of Falcon20 measurements at Francazal airport (c) C. Crevoisier
The team at Francazal… wearing masks due to the pandemic (c) C. Crevoisier

Day 4 – 12 September 2020

This day is devoted to the validation of total columns of CO2 retrieved from NASA OCO-2. One particularity: OCO-2 is making observations in glint-mode, mostly over ocean. Two EM27/SUN and CHRIS are deployed along the French oceanic coast at Hendaye, Anglet and CapBreton… under an unclouded sun. Some great measurements, along beautiful views and many questions from the people going to the beach!


Meanwhile, at Aire-sur-l’Adour, two AirCores and one Amulse are launched by the CNES-GSMA-LMD ‘masked’ teams.

The MAGIC2020 team at Aire-sur-l’Adour on Sept. 12th (c) C. Crevoisier

AirCores are first prepared for the flight: checking of the tube and the connectics, weighting (payload has to be below 3kg), balloon inflation by CNES team.

Preparation of AirCore flights (c) CNRS/LMD

Finally, ballon launches are coordinated with satellite overpasses : IASI at 9:08 UTC and OCO-2 at 12:59 UTC.

The ballonns launched on Sept. 12th: AirCore-1 at 8:00 UTC (colocation with IASI-A), AirCore-2 at 12:00 UTC (colocation with OCO-2) and Amulse at 12:30 UTC (colocation with OCO-2) (c) CNRS/LMD

After a flight of about 2h30, it is  time to recover the payload. Most of the AirCore and Amulse instruments have landed in crop fields… but some of them fancied landing on a  tree…

An AirCore landed in a tree, another one brought back to Aire-sur-l’Adour for analysis (c) M. Dogniaux / C. Crevoisier

The analysis of AirCores take some time, and the sun goes down on the horizon while the teams finish their analyses and preparer the paylaods for the following day…

Late work at Aire-sur-l’Adour… (c) M. Dogniaux

And the deers come to visit…

The deers come to visit the team at Aire-sur-l’Adour… (c) M. Dogniaux

Day 5 – 13 September 2020

Today sees the 4 ground-based Fourier Transform Spectrometers deployed together at Aire-sur-l’Adour. These instruments provide total columns of several trace gases, including CO2 and CH4. The goal of this simultaneous observations is to compare their measurements and calibration.

Moreover, this day is also devoted to  the validation of GOSAT-1 and -2 satellites that deliver total columns of CO2 and CH4. For the campaign, thanks to JAXA, both satellites made target mode acquisitons over Aire-sur-l’Adour.

Four Fourier Transform Spectrometers at Aire-sur-l’Adour: CNES/EM27SUN, GSMA/EM27SUN, LOA/CHRIS, LERMA/EM27/SUN (c) C. Crevoisier

To provide the knowledge of atmospheric conditions (temperature, water vapour and gas concentration profiles) that will help the interpretation of the atmospheric spectra recorded by the spetrometers, two AirCores and one Amulse are launched from the site.

AirCore launch at 8:30 UTC (colocation with IASI-B) next to the 4 Fourier Transform Spectrometers (c) C. Crevoisier
Amulse launch at 13:00 UTC (colocalisation with GOSAT-1&2) (c) M. Dogniaux



Because of a stronger wind that the previous days, a new technique is used to release the balloons… as illustrated here with the launch of the last balloons of the campaign, carrying GSMA/Amulse.









Day 6 – 14 September 2020

Spectral calibration of Fourier Transform Spectrometer by LERMA (c). C. Crevoisier


Last day of the campaign used to determine the Instrument Line Shape of the Fourier Transform Spectrometers by using the spectral calibration chain developed by LERMA. Meanwhile, it is packing and departure time for the other teams.







A final picture of the ‘masked’ team of MAGIC2020 at Aire-sur-l’Adour, including CNES, GSMA, LERMA, LMD and LOA. In summary: 13 ballon launches (9 AirCores and 4 Amulses), 3h30 flight for SAFIRE Falcon20, 4 ground-based spectrometers deployed at 7 locations alltogether with a daily average of 6 hours of continuous measurements, colocated measurements with 7 satellites (TROPOMI/Sentinel-5P, OCO-2, IASI-A/B/C, GOSAT-1/2). Congratulations to the team for this geat achievement!


The MAGIC2020 team at Aire-sur-l’Adour (c) C. Bès