May 31, 2017


Strateole-2 is a French-American project designed to study atmospheric events above the equator. It consists in launching several gigantic balloons capable of flying 18 to 20 km high for over 3 months. The first scientific campaign is scheduled for winter 2020-2021.

Earth’s equator is the site of our planet’s most powerful atmospheric events; their effects can be observed as far as the polar areas. However, many of these events remain largely misunderstood and are consequently poorly represented in meteorology and climate models. To fill this data gap from an area difficult to access for other means of observations, the Strateole-2 project aims to launch several balloons from the Indian Ocean. Two scientific campaigns are scheduled; one between November 2020 and April 2021, the other between November 2023 and April 2024.

Each campaign will launch 20 high-altitude pressure balloons, 11 to 13 meters in diameter transparent spheres filled with helium and capable of flying at an altitude of 18 to 20 km for over 3 months, in order to go around the Earth along the equator 2 to 3 times.

Some observations (temperature, wind, pressure) will be transmitted almost instantaneously to the World Meteorological Organisation (WMO) to improve weather forecast in tropical regions.

With its renowned expertise in balloon flight, CNES plays a central role in the Strateole-2 project, working in close collaboration with several French and American laboratories, including the Laboratoire de Météorologie Dynamique (Dynamic Meterology Laboratory, LMD), which is principal investigator on the project. The European Space Agency (ESA) also takes part in the mission to validate the Aladin instrument, scheduled to launch in late 2017 aboard the ADM-Aeolus satellite. Other instrument calibration and validation operations are being discussed. Strateole-2 is also part of the WMO’s SPARC climate programme.