Sensitivity of convection to environment within local neighborhoods

This study investigates sensitivity of convection to coincident atmospheric environment at meso-gamma spatial scales. The data used for the study comprise a large ensemble of three-dimensional high-resolution local domains that were extracted from cloud-resolving model simulations of different cases of subtropical and tropical convection over land and ocean.&#160; The simulations were produces as part of the NASA (National Aeronautics and Space Administration) INCUS (Investigation of Convective Updrafts) mission (van den Heever, 2021). The simulations include a diverse set of convective morphologies associated with different synoptic environments (Marinesku et al., 2024 ). &#160;Each neighborhood domain of dimensions 25.6 x 25.6 x 18 km, respectively in latitudinal, longitudinal and vertical direction, is centered on a deep convection core vertical profile that was selected for tracking convective cloud evolutions for the purpose of investigations within the INCUS mission &#160;(Sokolowsky et al. 2024 ). The ensemble of neighborhoods used in this study therefore represent a distribution of local convective states and the associated environments embedded in a wide range of larger scales environments.&#160;To capture relationships between convection and environment states over a range of spatial scales contained within the neighborhoods in a concise manner, the analysis was performed in a phase space of two-dimensional horizontal scales spectral powers that are associated with leading vertical principal components of the physical variables representing the convection and environment. The convection state &#160;was represented by vertical velocity and total condensate, and the environment by temperature, humidity, divergence and vorticity.&#160;The main finding is that the variability of vertical velocity and total condensate states at the convective scales (< 10 km)&#160; exhibits high insensitivity to the variability of the neighborhood domain average environment states. &#160;&#160;In contrast, notable co-variance was found between the vertical velocity and environment states at the convective scales, especially with the temperature mid-to-upper tropospheric warming variability and the variability of divergence in mid-troposphere and above 10 km.&#160; For the total condensate, significant co-variance was exhibited also between its neighborhood domain average and the the convection scale environment. &#160;This relationship reflects impact of the convective processed on the environment states including coupling between the convection dynamics and microphysics.In the context of convective scale data assimilation the findings suggest that for representation of the convection state variability at the convective scales would be weekly constrained &#160;in the absence of convective scale observations of the environment states.&#160;ReferencesMarinescu, P.J., van den Heever, S.C., Grant, L.D., Bukowski, J. and Singh, I., 2024. How Much Convective Environment Subgrid Spatial Variability Is Missing Within Atmospheric Reanalysis Data Sets?. Geophysical Research Letters, 51(24), p.e2024GL111856.Sokolowsky, G.A., Freeman, S.W., Jones, W.K., Kukulies, J., Senf, F., Marinescu, P.J., Heikenfeld, M., Brunner, K.N., Bruning, E.C., Collis, S.M. and Jackson, R.C., 2024. tobac v1. 5: introducing fast 3D tracking, splits and mergers, and other enhancements for identifying and analysing meteorological phenomena. Geoscientific Model Development, 17(13), pp.5309-5330.van den Heever, S. C. (2021). NASA selects new mission to study storms, impacts on climate models. NASA Earth (https://www.nasa.gov/press&#8208;release/nasa&#8208;selects&#8208;new&#8208;mission&#8208;to&#8208;study&#8208;storms&#8208;impacts&#8208;on&#8208;climate&#8208;models)&#160;