We thank Karen Rosenlof for helpful comments and discussions on earlier versions of the manuscript, and Damianos Mantsis for initial discussions regarding OLR metrics. This paper arises from discussions within the International Space Science Institute (ISSI) Tropical Width Diagnostics Intercomparison Project and the U.S. Climate Variability, Predictability and Change (U.S. CLIVAR) Working Group on the Changing Width of the Tropical Belt. The authors thank the entire members of these groups, the ISSI and U.S. CLIVAR offices, and sponsoring agencies (ESA, Swiss Confederation, Swiss Academy of Sciences, University of Bern, NASA, NOAA, NSF, and DOE). All model data used in this paper are freely available through the Earth System Grid Federation (https://pcmdi9.llnl.gov/projects/esgf-llnl/). We acknowledge the World Climate Research Programme’s Working Group on Coupled Modelling, which is responsible for CMIP, and we thank the climate modeling groups for producing and making available their model output. For CMIP, the U.S. Department of Energy’s Program for Climate Model Diagnosis and Intercomparison provides coordinating support and led development of software infrastructure in partnership with the Global Organization for Earth System Science Portals. DW acknowledges support from NSF AGS-1403676.
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