GISS‐E2.1: Configurations and Climatology
Maxwell Kelley, Gavin A. Schmidt, Larissa Nazarenko, Susanne E. Bauer, Reto Rüedy, Gary L. Russell, Andrew S. Ackerman, Igor Aleinov, Michael Bauer, Rainer Bleck, V. M. Canuto, G Cesana, Y. Cheng, Thomas L. Clune, Ben Cook, Carlos Alberto dos Santos Cruz, Anthony D. Del Genio, Gregory S. Elsaesser, G. Faluvegi, Nancy Y. Kiang, Daehyun Kim, Andrew A. Lacis, Anthony Leboissetier, Allegra N. LeGrande, Ken K. Lo, John Marshall, Elaine E. Matthews, Sonali McDermid, Keren Mezuman, R. L. Miller, Lee T. Murray, Valdar Oinas, Clara Orbe, Carlos Pérez García‐Pando, J. P. Perlwitz, Michael J. Puma, David Rind, Anastasia Romanou, Drew Shindell, Shan Sun, Nick Tausnev, Kostas Tsigaridis, George Tselioudis, Ensheng Weng, Jingbo Wu, Mao‐Sung Yao
Abstract
Abstract This paper describes the GISS‐E2.1 contribution to the Coupled Model Intercomparison Project, Phase 6 (CMIP6). This model version differs from the predecessor model (GISS‐E2) chiefly due to parameterization improvements to the atmospheric and ocean model components, while keeping atmospheric resolution the same. Model skill when compared to modern era climatologies is significantly higher than in previous versions. Additionally, updates in forcings have a material impact on the results. In particular, there have been specific improvements in representations of modes of variability (such as the Madden‐Julian Oscillation and other modes in the Pacific) and significant improvements in the simulation of the climate of the Southern Oceans, including sea ice. The effective climate sensitivity to 2 × CO 2 is slightly higher than previously at 2.7–3.1°C (depending on version) and is a result of lower CO 2 radiative forcing and stronger positive feedbacks.