Quantifying the Vertical Transport in Convective Storms Using Time Sequences of Radar Reflectivity Observations.

A new satellite observation concept to estimate upward air mass flux in convective storms has been proposed using a convoy of small radars that measure reflectivity only. The approach is to analyze a pair of radar reflectivity profiles obtained within 30–120 s of one another, and infer the upward transport above the freezing level and at a nominal 3‐km horizontal resolution from the reflectivities and their temporal change. This paper summarizes the theoretical basis for this approach, with quantitative justification using sensitivity analyses of convection‐permitting model simulations and from ground‐based zenith profiler data. We then describe and quantify the performance of the approach to detect updrafts from the radar observations. Finally, we illustrate the expected performance of retrievals of the vertical transport and evaluate their ability to meet the objectives of the "Investigation into Convective Updrafts" mission, selected by NASA to place in orbit in 2027–2028 a convoy of three identical Ka‐band radars measuring radar reflectivity within their common swath. Plain Language Summary: This paper describes a new concept to measure the vertical transport in updrafts in convective storms, from space, using pairs of small radars that measure radar reflectivity only. The paper first presents the theoretical relation between the evolution of reflectivity from the time of the first radar observation to the time of the last (up to 2 min later), on one hand, and the underlying vertical velocities in the updraft. The paper then demonstrates the forward‐sensitivity of reflectivity, under the practical radar constraints, to the vertical velocities. And finally the paper demonstrates the ability to invert this forward sensitivity and produce retrievals of vertical velocity with low uncertainty. Key Points: A new satellite observation concept to estimate air mass transport in convective updrafts is explainedIt is shown that chronological sequences of radar reflectivities are sensitive to the characteristics of vertical transportIt is shown how the characteristics of the vertical transport can be derived from the radar observations [ABSTRACT FROM AUTHOR]