JOANNE : Joint dropsonde Observations of the Atmosphere in tropical North atlaNtic meso-scale Environments

As part of the EUREC4A field campaign which took place over the tropical North Atlantic during January-February 2020, 1216 dropsondes from the HALO and WP-3D aircraft were deployed through 26 flights to improve the current understanding of the atmospheric environment in the trade-wind regions, complementing simultaneous measurements from a multitude of platforms. We present JOANNE, the dataset that contains these dropsonde measurements of temperature, pressure, relative humidity and horizontal winds, along with the products derived from them to characterize the dynamic and thermodynamic environment in the trade-wind regions. Together with the raw measurement profiles and basic post-processing, the dataset also includes a homogenized and gridded data set with 10 m vertical spacing (Level 3 product). The gridded data are used as a basis for deriving diagnostics of the area-averaged meso-scale circulation properties such as divergence, vorticity, vertical velocity and gradient terms (Level 4 product), making use of sondes dropped at regular intervals along a circular flight path. 85 such circles, 222 km in diameter, were flown during EUREC4A. The sampling strategy for dropsonde measurements during EUREC4A, the quality control for the data, the methods of estimation of additional products from the measurements and the different post-processed levels of the dataset are explained in the JOANNE publication on ESSD.