Assessing mean climate change signals in the global CORDEX-CORE ensemble

Abstract

The new Coordinated Output for Regional Evaluations (CORDEX-CORE) ensemble provides high-resolution, consistent regional climate change projections for the major inhabited areas of the world. It serves as a solid scientific basis for further research related to vulnerability, impact, adaptation and climate services in addition to existing CORDEX simulations. The aim of this study is to investigate and document the climate change information provided by the CORDEX-CORE simulation ensemble, as a part of the World Climate Research Programme (WCRP) CORDEX community. An overview of the annual and monthly mean climate change information in selected regions in different CORDEX domains is presented for temperature and precipitation, providing the foundation for detailed follow-up studies and applications. Initially, two regional climate models (RCMs), REMO and RegCM were used to downscale global climate model output. The driving simulations by AR5 global climate models (AR5-GCMs) were selected to cover the spread of high, medium, and low equilibrium climate sensitivity at a global scale. The CORDEX-CORE ensemble has doubled the spatial resolution compared to the previously existing CORDEX simulations in most of the regions (25$$\,\mathrm {km}$$ km (0.22$$^{\circ }$$ ∘ ) versus 50$$\,\mathrm {km}$$ km (0.44$$^{\circ }$$ ∘ )) leading to a potentially improved representation of, e.g., physical processes in the RCMs. The analysis focuses on changes in the IPCC physical climate reference regions. The results show a general reasonable representation of the spread of the temperature and precipitation climate change signals of the AR5-GCMs by the CORDEX-CORE simulations in the investigated regions in all CORDEX domains by mostly covering the AR5 interquartile range of climate change signals. The simulated CORDEX-CORE monthly climate change signals mostly follow the AR5-GCMs, although for specific regions they show a different change in the course of the year compared to the AR5-GCMs, especially for RCP8.5, which needs to be investigated further in region specific process studies.

Editorial for the CORDEX-CORE Experiment I Special Issue

“…The SI starts with two papers presenting an overarching analysis of the full CORDEX-CORE EXP-I ensemble, including both RCMs and all domains. Teichmann et al (2021) In all papers of the SI, within the scientific questions they address, comparisons between RCM and driving GCM signals are presented with the aim of identifying the added value of the RCM downscaling. However, the paper by Ciarlo et al (2020) focuses specifically on this topic, and investigates a new distributed metric of added value based on daily precipitation intensity distributions of both present day and future climate.…”

Examination of potential impacts of future climate change on solar radiation in Togo, West Africa

“…The oceanic boundary conditions for the simulations were taken from the driven GCM with the choice of shallow convection scheme and MM5 Non-Hydrostatic core without large-scale option [34][35][36]. The Lake Coupling described in [39] with modification after [40] were adopted.…”

“…The Lake Coupling described in [39] with modification after [40] were adopted. Detailed descriptions of the configuration, initial and lateral boundary conditions as well as various improved schemes adopted in the CORDEX models have been well documented in the literature [34][35][36][37][38][39][40]. The future climate projections were carried out for two emission scenarios: RCP 2.6 and RCP8.5 of low and high range mitigation scenarios, respectively [41].…”

COSMO-CLM regional climate simulations in the Coordinated Regional Climate Downscaling Experiment (CORDEX) framework: a review

“…The COSMO-CLM model has been used for a large set of experiments and run over a wide range of timescales (up to a century) and resolutions (1-50 km) (e.g., Ban et al, 2014;Brisson et al, 2015;Chatterjee et al, 2017;Wouters et al, 2017;Leutwyler et al, 2017;Schultze and Rockel, 2018;Schlemmer et al, 2018;Imamovic et al, 2019;Panosetti et al, 2019;Hentgen et al, 2019;Brogli et al, 2019). COSMO-CLM has been used to perform regional climate simulations over Europe for more than 15 years , has today been extensively used for climate simulations over multiple domains around the globe (e.g., Panitz et al, 2014;Asharaf and Ahrens, 2015;Bucchignani et al, 2016b;Keuler et al, 2016;Sørland et al, 2018;Hirsch et al, 2019;Li et al, 2018;Termonia et al, 2018;Di Virgilio et al, 2019;Russo et al, 2020;Drobinski et al, 2020;Evans et al, 2020), and in this way contributed to the CORDEX initiative. Rockel and Geyer (2008) investigated how COSMO-CLM performs over various domains and climate zones when keeping intentionally the same setup as for its "home domain", which was introduced as model transferability (Takle et al, 2007).…”