Artist’s impression of EarthCARE © Esa
EarthCARE has taken off. This satellite from the European Space Agency (ESA) developed jointly with the Japanese Space Agency (JAXA) took off this Tuesday, May 28 aboard a SpaceX Falcon 9 rocket, from the Vandenberg military base, in California. Designed to operate for at least three years, EarthCARE will study aerosols and clouds in order to understand their role in warming and cooling the atmosphere and therefore on the climate.
Understanding the role of clouds, aerosols and radiation on the climate
The objective of EarthCARE is complex: its observations should make it possible to understand the close relationships between cloud cover, aerosols (i.e. fine particles suspended in the atmosphere) and the radiative environment of Earth. The interaction between these three components plays a fundamental, and still poorly understood, role in the earth’s climate: does it contribute to increasing the global temperature, and thus to exacerbating global warming or, on the contrary, does it attenuate it? ? A crucial question that is very difficult to answer as there are so many variables. For example, clouds are not all the same, and differ depending on altitude. Thus, they do not absorb and reflect solar radiation and the heat emitted by the Earth in the form of infrared radiation in the same way. Therefore, the climate impacts are different. These parameters must therefore be taken into account in the digital models which study the climate, and which EarthCARE proposes to improve thanks to the data it will collect and which will make it possible to develop a three-dimensional map of cloud cover and aerosols and to measure solar and terrestrial thermal radiation.
Artist’s impression of the satellite launch © ESA
For this, the satellite will follow a low polar orbit, around 400 km above the Earth, designed to fly over the same point every 9 days. Thus, by comparison between these different passages, EarthCARE will demonstrate the evolution of its readings during its three years of flight.
To do this, the satellite carries with it four instruments. A lidar, ATLID, which will scan the tops of the clouds, their profiles and the surrounding aerosols. A radar, CPR, which will focus on the vertical structure, movement and internal dynamics of clouds. An imaging spectrometer, MSI, which will observe the atmosphere in several wavelengths. And a radiometer, BBR, which will measure the solar radiation reaching us and the infrared radiation emitted by the Earth.
An Earth Explorer mission
EarthCARE takes place within ESA’s Living Planet program, which aims to develop Earth observation missions. Among these missions, Earth Explorer missions are particularly focused on achieving objectives for research purposes: EarthCARE is one of them. Proposed in 2000 following a call for projects, EarthCARE was officially selected at the end of 2004 as the sixth Earth Explorer mission supported by the ESA.