ESA's EarthCARE studies cloud physics to improve climate models

The European Space Agency’s EarthCARE or Earth Cloud Aerosol and Radiation Explorer, an advanced cloud-research satellite, has been successfully launched. It was sent into orbit on 28 May aboard a SpaceX Falcon 9 rocket from Vandenberg Space Force Base in California.

Designed to study cloud dynamics, the satellite will soon be providing climate scientists and meteorologists with accurate data about the complex interactions between clouds, aerosols and radiation. This will help them devise better climate models, predict extreme weather events and provide more accurate assessments of future global warming, assisting climate science and policy.

“Clouds are the largest source of uncertainty in climate prediction,” says Robin Hogan, a principal scientist at the European Centre for Medium-Range Weather Forecasts. “EarthCARE is going to give us much, much more detail about the actual properties of clouds, so enable us to understand them, to hopefully narrow this range of uncertainty.”

EarthCARE deploys a suite of instruments, including radar, lidar and a broadband radiometer, designed to provide insight into cloud dynamics, the role of aerosols and how different cloud formations contribute to planetary warming or cooling depending on whether they reflect the sun’s radiation or absorb it.

The onboard radar penetrates deep into clouds, measuring the speed of particles in the atmosphere. This will improve our understanding of precipitation and how air rises inside clouds, a driver of thunderstorms. The lidar instrument uses ultraviolet light to detect ice and aerosols in clouds and, for the first time, discern differences in the sizes and types of particles – from sand and sea salt to soot and other pollutants – giving detailed information on the impact they have on atmospheric heating and cooling, which is measured by the broadband radiometer.

The satellite will now undergo a calibration phase to test its instruments before scientific data collection can begin, a process expected towards the end of the year. “We’ve got lots of scientific work to do, of course,” says Hogan, “but we’ve got every reason to believe that this is going to be a step change in our understanding of how we should represent clouds in our climate models to make better predictions of climate in the future.”