Morphology of the Simulated Convective Updrafts in the Incus Collection of Reference Simulations

NASA's INvestigation of Convective UpdraftS (INCUS) mission has built a large collection of basin-scale convection-permitting-model simulations representing the fine-scale evolution of the atmospheric state during a large variety of convective events. In addition to its dependence on the uncertainty in initial and boundary conditions, the accuracy of these simulations in representing the large-scale storms and their evolution depends crucially on the detailed assumptions about quantities and processes that are not explicitly represented by the model -- the inevitable uncertainties in these assumptions creating errors which grow in space and time, leading (in the case of convective storms) to possibly large errors over domains and time scales that are comparable to those of typical storms. However, the model has sufficiently fine spatial resolution (100 m in the innermost grid of the nested domains) and sufficient realism in the representation of the not-explicitly-resolved physics at that scale to produce local solutions that should be quite accurate in their representation of the evolution of the atmospheric state locally, certainly in any neighborhood consisting of a handful of horizontal kilometers (comparable to the INCUS radar resolution) over a couple of minutes (the nominal separation between leading and trailing satellites in the INCUS convoy).

Therefore, viewing this large collection of basin-scale simulations not as a representation of the variety of storms that can occur, but rather as a representation of the variety of (local) convective updrafts that occur, one can extract neighborhoods about all the detected simulated updrafts, and analyze the characteristics of the updrafts in these neighborhoods statistically, considering the collection of harvested updrafts to be representative of what natural storms produce (and are produced by). Tantalizing questions include: is there an objective separation between "shallow" and "deep" convective updrafts? is there a relation between updraft base and updraft intensity? is there a relation between updraft intensity and updraft horizontal size? The (very interesting) answers to these -- and other basic -- questions about the morphology of convective updrafts as derived from statistical analyses of the INCUS collection of basin-scale simulations will be presented and discussed.

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