The dataset includes post-processed model outputs from 12 regional configuration moisture-sensitivity simulations using the MPAS-A version 7.3. The Limited-Area domain encompasses 30 degree S to 51 degree N and -65 degree W to 59 degree E. A 15km by 3km variable-resolution mesh is used with the 3km refinement region elliptically shaped. The mesh is rotated 5 degree to ensure the track of pre-Helene remains within the refined region. The refined region is over Africa and parts of the Atlantic. The reason to use a combined Limited-Area and variable-resolution mesh is to be computationally effective while giving sufficient resolution at the edge of the domain for the initial and lateral boundary conditions to be assimilated and resolved appropriately. The model was initialized using ERA5 data to simulate the period of the African easterly wave (AEW) that became hurricane Helene in 2006 as in: https://doi.org/10.5065/t224-6s94. The regional configuration is used to allow altering initial and lateral boundary conditions of relative humidity (RH) through the entire atmospheric column using ERA5 pressure-level data. Perturbed experiments are done by randomly perturbing temperature at 1000 hPa (Gaussian with 0.6 K standard deviation). The dataset can be used to study this specific AEW case and other easterly waves, mesoscale convective systems, African weather, West African Monsoon, ITCZ, etc. Although the model produces 15km by 3km horizontal grid outputs, the post-processed outputs available here were interpolated to a 0.25-degree by 0.25 degree latitude by longitude grid and 27 isobaric levels (in the vertical).
More details of the data and analysis are published in the Journal of Advances in Modeling Earth Systems (JAMES): Nunez Ocasio et al. 2024. https://doi.org/10.1029/2023MS004070
