Enhancing our Understanding of Tropical Convective Processes through the INCUS Mission

The transport of air and water by tropical convective systems assists in driving the large-scale circulation, determines convective anvil properties and their cloud radiative forcing, and is integrally linked to fresh water and extreme weather. This convective mass flux (CMF) forms the focus of the recently selected NASA Investigation of Convective Updrafts (INCUS) mission to be launched in 2026. INCUS is comprised of a train of three SmallSats, each of which will carry a Ka-band cloud radar, and one of which will also house a passive microwave radiometer. The three SmallSats are separated by time intervals of 30, 90 and 120 seconds which, together with the cross-track scanning radars, will facilitate the rapid and systematic sampling of the same storm by all three spacecraft, and will provide observations of the magnitude and evolution of CMF within tropical convective storms. INCUS will therefore provide the first global systematic investigation into CMF, and its variation as a function of storm type, storm lifecycle and environmental properties.

A wide range of research tasks have been conducted during the development states of the INCUS mission including: (1) conducting and analyzing extensive suites of large-domain, high-resolution model simulations; (2) examining Doppler radar observations obtained at time intervals similar to that of INCUS using adaptive scanning techniques during several recent field campaigns; and (3) evaluating convective anvil properties using passive microwave radiometer and geoIR data. Following a brief description of the INCUS mission, this talk will focus on three specific highlights arising from these modeling and observational analyses. First, we will demonstrate proof of the INCUS delta-t concept by linking changes in radar reflectivity to CMF through the use of ground-based radar analyses. Second, we will analyze the relationship between ice water path cores and convective updrafts within convective anvils. Finally, we will characterize the updraft variability evident in the high-resolution simulations.