The Low‐Resolution Version of HadGEM3 GC3.1: Development and Evaluation for Global Climate

作者：Till Kuhlbrodt, Colin Jones, Alistair Sellar, David Storkey, Ed Blockley, Marc Stringer, Richard S. Hill, Tim Graham, Jeff Ridley, Adam T. Blaker, Daley Calvert, Dan Copsey, Richard J. Ellis, Helene T. Hewitt, Patrick Hyder, Sarah Ineson, Jane P. Mulcahy, Antony Siahaan, Jeremy Walton · 发表于：Journal of Advances in Modeling Earth Systems · 年份：2018 · DOI：10.1029/2018ms001370 · 被引用次数：361 · 研究领域：Climate variability and models、Meteorological Phenomena and Simulations、Atmospheric and Environmental Gas Dynamics

A new climate model, HadGEM3 N96ORCA1, is presented that is part of the GC3.1 configuration of HadGEM3. N96ORCA1 has a horizontal resolution of ~135 km in the atmosphere and 1° in the ocean and requires an order of magnitude less computing power than its medium-resolution counterpart, N216ORCA025, while retaining a high degree of performance traceability. Scientific performance is compared to both observations and the N216ORCA025 model. N96ORCA1 reproduces observed climate mean and variability almost as well as N216ORCA025. Patterns of biases are similar across the two models. In the northwest Atlantic, N96ORCA1 shows a cold surface bias of up to 6 K, typical of ocean models of this resolution. The strength of the Atlantic meridional overturning circulation (16 to 17 Sv) matches observations. In the Southern Ocean, a warm surface bias (up to 2 K) is smaller than in N216ORCA025 and linked to improved ocean circulation. Model El Niño/Southern Oscillation and Atlantic Multidecadal Variability are close to observations. Both the cold bias in the Northern Hemisphere (N96ORCA1) and the warm bias in the Southern Hemisphere (N216ORCA025) develop in the first few decades of the simulations. As in many comparable climate models, simulated interhemispheric gradients of top-of-atmosphere radiation are larger than observations suggest, with contributions from both hemispheres. HadGEM3 GC3.1 N96ORCA1 constitutes the physical core of the UK Earth System Model (UKESM1) and will be used exten...