What are the interactions between aerosols and clouds? How much solar and earth surface radiation are reflected or absorbed by these phenomena? These are some of the questions that will be answered thanks to EarthCARE, which will contribute to the knowledge of radiative transfer in the atmosphere and will allow us to understand how these natural elements influence the planet's delicate temperature balance. For the first time, the mission will be able to provide vertical profiles of clouds and aerosols from space, on a planetary scale, helping to improve the accuracy of climate models.
In this context, Leonardo has developed some of the technologies that will go into orbit on board the ESA mission. An example is the laser transmitter for the ATLID instrument, built in the Pomezia (RM) and Campi Bisenzio (FI) sites, which will help collect data on aerosol and cloud particles. The laser is composed of approximately eighty optical elements, designed to remain perfectly aligned even during the extreme environmental conditions, such as vibrations during launch, absence of gravity and low temperatures in orbit. From space, it can observe tiny particles in the atmosphere, which are less than a thousandth of a millimeter in size or thirty times smaller than the thickness of a hair. To achieve this, the transmitter emits about 3,000 very short ultraviolet pulses per minute. These are “reflected” by aerosols (such as thin solid particles, liquid droplets suspended in the air or other gas) or from thin clouds, to generate a return signal containing information on the distance and type of particles observed and subsequently analysed by the receiver of the ATLID instrument.
