P44     Sensitivity experiments of urban canopy parameterizations using ensemble WRF simulations over the Chicago metropolitan.

Sever, Gökhan, Rob Jacob, Rajeev Jain, Aleks Obabko, Rao Kotamarthi, and Charlie Catlett, Argonne National Laboratory

Forecasting the weather at urban-scales requires the development of models that are capable of running at a few cubic meters resolution as well as physical representations of the atmosphere that are verified at scales relevant to buildings. The Multiscale Coupled Urban Systems exascale computing project has designed possible pathways to handle the large computational and data requirements of such future modeling infrastructure. While similar efforts have shown rapid progression in recent years, observational data that captures the high spatio-temporal pulse of weather that models are designed upon and verified against have not scaled up with the computational advancements. Synergistic efforts between the computational and observational fronts are essential to making the forecasting of weather a reality at building scales.
We performed High-Resolution Rapid Refresh (HRRR) initialized Weather Research and Forecasting (WRF) model simulations over the Chicago region for the entirety of 2018. Three kilometers to a few hundreds of meters horizontal resolution configurations allow the model to capture meso and micro scale weather evolution from hours to seconds. The impact of buildings are treated with multi-layer urban canopy parameterizations with different land-surface and planetary boundary layer schemes. Basic atmospheric measurements obtained with the Array-of-Things sensors will be used to validate model results within the metropolitan area. In addition, we plan to verify parameterized urban effects using an explicit building resolving model. The ensemble simulations will provide a basis to better understand mechanical and thermal processes within complex atmospheric boundary layer of Chicago which are locally affected by buildings, urban heat island, and land-sea breeze forcings.