High-Resolution Historical and Pseudo Global Warming (PGW) Simulations for northwest North America Catalogue (HR-HiPNWNAC), V1

This catalogue includes model output data from two 11-year simulations performed using the version 6 of the Canadian Regional Climate Model (CRCM6-GEM5). CRCM6-GEM5 (Roberge et al., 2024) is a climate model developed at ESCER/UQAM that is based on the version 5 of the Global Environmental Multiscale (GEM5) model (McTaggart-Cowan et al., 2019), the CLASS land surface scheme (Verseghy 2000) and the FLake lake model (Martynov et al., 2012). GEM5 is developed by the group of Recherche en Prévision Numérique at Environment and Climate Change Canada (ECCC) and is used for numerical weather prediction in multiple weather prediction systems. CLASS is developed by the Canadian Centre for Climate Modelling and Analysis also at ECCC as part of the new CLASSIC scheme. The two simulations were performed using a 2.5-km horizontal grid spacing version of the CRCM6-GEM5 model (CRCM6-GEM5-2.5), following a similar configuration as described in Roberge et. al (2024). The main difference is that we used version 5.1.1 of the GEM5 model here, instead of version 5.0.2. The simulated domain has 940 and 844 grid points in the east-west and north-south directions respectively. The domain is centered over British Columbia, Alberta, Saskatchewan and covers a portion of northwest North America. The two CRCM6-GEM5-2.5 simulations differ on the driving data used at the lateral boundaries. The historical climate simulation (denoted as hist) is driven by a 12-km version of the model that was in turn driven by the ERA5 reanalysis (Hersbach et al., 2020). The future climate simulation (denoted as pgw) is driven by a 12-km version of the CRCM6-GEM5 model (CRCM6-GEM5-12) that was also driven by the ERA5 reanalysis, but with an additional delta climate change perturbation, using the so-called Pseudo Global Warming (PGW) approach (Schär et al., 1996, Kröner et al., 2017) to simulate future changes. The climate change perturbation was taken from monthly mean fields averaged across an ensemble of 30 General Circulation Models (GCMs) from the sixth Coupled Model Intercomparison Project (CMIP6). The climate change signal was calculated between the periods 1990-2014 and 2076-2100 using the scenario SSP585. More details about the list of CMIP6 GCMs, the variables used and the interpolation into the ERA5 grid are provided in Argüeso (2023). The intermediate CRCM6-GEM5-12 simulations were run using spectral nudging in the interior of the domain as in Roberge et. al (2024), while the CRCM6-GEM5-2.5 simulations were only driven at the lateral boundaries by the CRCM6-GEM5-12 simulation.