Comparison of spaceborne retrieved vertical velocity and latent heating profiles using the EarthCARE–GPM coincidence dataset

Latent heat (LH) released by precipitating cloud systems is a primary driver of vertical air motion (V_air) within clouds and plays a crucial role in transporting energy from the Earth’s surface to the atmosphere. In the Tropical Rainfall Measuring Mission (TRMM) and its successor, the Global Precipitation Measurement (GPM) mission, LH profiles associated with condensation and evaporation processes have been estimated using precipitation observations from spaceborne Ku-band radars. In contrast, Doppler radar measurements from the Cloud Profiling Radar (CPR) onboard the Earth Cloud Aerosol and Radiation Explorer (EarthCARE) enable global observations of vertical motions within clouds. V_air is retrieved by subtracting estimated hydrometeor fall speeds, inferred from radar reflectivity together with collocated atmospheric lidar and multispectral imager observations, from the measured Doppler velocities. With these complementary observations, we investigated how consistent the GPM-derived LH profiles are with the EarthCARE-derived V_air profiles.

We have developed the EarthCARE–GPM coincidence dataset, which compiles cases in which the ground tracks of the two satellites intersect. The dataset extracts data from coincident segments while preserving the original structure of all Level-2 standard products from the four EarthCARE sensors, namely the cloud radar, lidar, imager, and broad-band radiometer, as well as the two GPM sensors, namely the precipitation radar and microwave radiometer. Using this dataset, we directly compared V_air derived from EarthCARE Doppler measurements, including both the JAXA’s standard product and an alternative retrieval based on the method introduced in Aoki et al. (2026), with LH profiles from the GPM Spectral Latent Heating product. Analyses classified by precipitation type reveal physically consistent relationships. Convective precipitation exhibits deep tropospheric heating accompanied by upward motions throughout the column. In contrast, stratiform precipitation shows top-heavy heating above the melting layer with corresponding upper-level ascent, while both LH and V_air are close to zero in the lower troposphere. Nevertheless, substantial uncertainties remain in the estimation of each product, and continued intercomparison between these complementary observations remains important for assessing and improving the reliability of both estimates.