EarthCARE – The joint ESA/JAXA Cloud Aerosol and Radiation Explorer Satellite First Data

The influence of clouds on incoming solar and reflected thermal radiation remains the largest contribution to the overall uncertainty in climate feedback due to the diverse cloud formation processes and their complex interaction with solar and thermal radiation. Furthermore, climate models still show deficiencies in correctly representing aerosol-cloud interactions (ACI) and precipitation patterns, limiting the overall confidence in climate predictions.

Global observations of vertical cloud ice and liquid water profiles with simultaneous and collocated solar and thermal flux observation will provide crucial data to address these uncertainties. Furthermore, collocated global observation of vertical aerosol profiles and types are required to address their direct effects and indirect ACI effects.

In response to these needs, the European Space Agency (ESA), in cooperation with the Japan Aerospace Exploration Agency (JAXA), have launched the Earth Cloud Aerosol and Radiation Explorer, EarthCARE, on a SpaceX Falcon-9 rocket on 29 May 2024 from Vandenberg, California, USA.

The two active instruments embarked on the satellite, a cloud-aerosol lidar (ATLID) and a cloud Doppler radar (CPR), together with the passive multispectral imager (MSI) and broad-band radiometer (BBR), have started to provide data to synergistically derive vertical profiles of cloud ice and liquid water, aerosol type, precipitation, as well as heating rates, solar and thermal top-of-atmosphere radiances, with the objective to reconstruct top-of-the-atmosphere short- and longwave fluxes at an accuracy of 10 Wm^-2 on a 10km×10km scene.

EarthCARE data products are developed by ESA and JAXA in a coordinated approach ensuring continuous information exchange between European and Japanese algorithm teams. Both agencies will ensure the free and open dissemination of EarthCARE data to the science community, with the intention to disseminate instrument Level 1b data six months, single-instrument Level 2a data nine months, and synergistic Level 2b data 18 months after launch.

The first six months after launch will be dedicated to commissioning of the satellite and instruments, with in-orbit calibrations, functional and performance testing.

Following the successful launch and the early operations phase, the satellite has entered the six-month commissioning phase dedicated to functional and performance testing of the platform and payloads, as well as the instruments’ in-orbit calibrations. After only three months, all four instruments are providing science data to the commissioning teams, with “first light “images presented to the science community.

The data quality will be guaranteed through dedicated projects, such as ESA’s Data Innovation and Science Cluster (DISC), bringing together instrument and product experts to establish a comprehensive product quality assurance framework. In addition, the EarthCARE validation team (ECVT) with more than 45 Cal/Val projects, often combining several teams and measurement capabilities, and currently including 14 field campaigns, will provide crucial independent information through monitoring, calibration and dedicated observation activities. Airborne activities underflying the satellite with remote sensing and in-situ payloads, flanked by dedicated ground-based calibration and measurement activities, have already started in August 2024 aiming to stabilize the data quality early in the EarthCARE mission.

The presentation will provide an up-to-date overview of the mission and science status based on the first six months of EarthCARE in orbit. It will introduce the mission’s science objectives, main performances of the three ESA instruments and one Japanese instrument, expected science advances, validation activities, as well as providing information on the data quality assurance and dissemination activities.