Just a quick note – we published a paper in HESS that evaluates ICAR thoroughly in the complex topography of the Southern Alps on the South Island of New Zealand. Specifically we’ve been looking at ICAR downscaled 4×4 km² precipitation fields and how they compare to weather station data and an operational gridded precipitation product supplied by NIWA. ICAR was forced with the ERA-Interim reanalysis.

Our results in two sentences: ICAR improves over the driving model but underestimates precipitation amounts and the performance strongly depends on your choice of the elevation of the top boundary (model top). Particular clear improvements are found for cross-alpine flow and flows of high linearity (as quantified with the inverse dimensionless mountain height).

Horak, J., Hofer, M., Maussion, F., Gutmann, E., Gohm, A., and Rotach, M. W.: Assessing the added value of the Intermediate Complexity Atmospheric Research (ICAR) model for precipitation in complex topography, Hydrol. Earth Syst. Sci., 23, 2715-2734, https://doi.org/10.5194/hess-23-2715-2019, 2019.