EarthCARE algorithms for retrieval of clouds, aerosols and vertical air motions  

<p>Clouds, aerosols and vertical air motions are essential components to control climate systems. We need better Earth observing systems that can provide aerosol-, cloud- and precipitation microphysics, their radiation properties and in-cloud air motions to reduce uncertainties in climate change predictions. The Earth Clouds Aerosol and Radiation Explorer (EarthCARE) is a joint mission by Japan Aerospace Exploration Agency (JAXA) and the European Space Agency (ESA). It will carry Doppler cloud profiling radar (CPR), atmospheric high spectral resolution lidar (ATLID), multi-le spectral imager (MSI) and broad band radiometer (BBR). JAXA EarthCARE algorithms have been developed. Doppler capability of CPR is expected to provide terminal velocity of cloud and precipitation particles and vertical air motion inside clouds. High spectral resolution and polarization functions of ATLID provides true backscattering coefficient, extinction coefficient and depolarization ratio. Theoretical studies indicated that the two-dimensional diagram of lidar ratio and depolarization ratio is essential for discriminating among cloud particle shapes and orientations (Okamoto et al., 2019, Okamoto et al., 2020) in addition to aerosol types. Recently developed physical model (Sato et al., 2018) and vectorized physical model (Sato et al., 2019) can be used to take lidar multiple scattering into account for the interpretation of active sensor signals of optically thick clouds. Synergy of new observations with the theoretical improvements enables better cloud microphysics retrievals, leading to better estimation of radiative properties of cloud and precipitation particles and aerosol-cloud interactions.&#160;Synergetic ground-based observation systems are developed to evaluate the EarthCARE algorithms for space-borne active sensors. The systems consist of Multi-Field-of-view Multiple Scattering Polarization Lidar (Okamoto et al., 2016, Nishizawa et al., 2021), high spectral resolution lidar using a scanning Michelson interferometer (Jin et al., 2020), Direct detection Doppler lidar (Ishii et al., 2022) and 94 GHz cloud radar. The systems are designed to capture the characteristics of CloudSat, CALIPSO, and EarthCARE, leading to bridge the gap of these satellite data sets.&#160;&#160;</p>