MESACLIP: Nominal 1-degree CESM (low-resolution) simulations corresponding to high-resolution experiments

Over the past six years, our research team consisting of scientists at Texas A&M University (TAMU) and the U.S. National Science Foundation National Center for Atmospheric Research (NSF NCAR) has made major breakthroughs in advancing high-resolution global climate modeling and prediction. We have completed several thousand years of climate simulations at a tropical cyclone (TC) permitting and ocean-eddy-rich resolution (hereafter simply referred to as CESM-HR) as part of our NSF-funded project entitled "Understanding the Role of MESoscale Atmosphere-Ocean Interactions in Seasonal-to-Decadal CLImate Prediction (MESACLIP)". Among others, we completed a 500-year preindustrial control (PI-CTRL) simulation forced by a perpetual climate forcing that corresponds to the year 1850 conditions and a 10-member ensemble of historical and future transient climate simulations.

The CESM-HR configuration is based on an earlier CESM version, CESM1.3, with many additional modifications and improvements. CESM-HR uses a 0.25 degree grid in the atmosphere and land components and a 0.1 degree grid in the ocean and sea-ice components. The primary reason for using an older model version, instead of the latest CESM2, is that CESM2 does not support a high-resolution version per the decision by the CESM Scientific Steering Committee. The component models within CESM1.3 are the Community Atmosphere Model version 5 (CAM5; Neale et al., 2012), the Parallel Ocean Program version 2 (POP2; Danabasoglu et al., 2012; Smith et al., 2010), the Community Ice Code version 4 (CICE4; Hunke & Lipscomb, 2008), and the Community Land Model version 4 (CLM4; Lawrence et al., 2011).

Here we release the nominal 1 degree low-resolution (LR) equivalent simulations based on the same CESM1.3 code base and using the same CAM5 Spectral Element (SE) dycore used in CESM-HR to permit an as-clean-as-possible comparison of the respective LR and HR simulations. CESM LR uses a nominal 1 degree grid in all its components.

Citation: The two papers linked below are the most appropriate references for these simulations. To cite the dataset, use Chang et al. (2025). We ask that you also cite the dataset itself using the reference Castruccio et al. [https://rda.ucar.edu/datasets/d651030/citation/] (2024) in any documents or publications using these data. Chang et al. (2020) describes the initial CESM-HR simulations, including the 500-year pre-industrial control simulation and the first 250-year historical and future climate simulation from 1850 to 2100. It also introduces the corresponding CESM LR experiments. We would also appreciate receiving a copy of the relevant publications. This will help us to justify keeping the data freely available online in the future. Thank you!