Open AccessSPEAR: The Next Generation GFDL Modeling System for Seasonal to Multidecadal Prediction and Projection
Author(s) -
Delworth Thomas L.,
Cooke William F.,
Adcroft Alistair,
Bushuk Mitchell,
Chen JanHuey,
Dunne Krista A.,
Ginoux Paul,
Gudgel Richard,
Hallberg Robert W.,
Harris Lucas,
Harrison Matthew J.,
Johnson Nathaniel,
Kapnick Sarah B.,
Lin ShianJian,
Lu Feiyu,
Malyshev Sergey,
Milly Paul C.,
Murakami Hiroyuki,
Naik Vaishali,
Pascale Salvatore,
Paynter David,
Rosati Anthony,
Schwarzkopf M.D.,
Shevliakova Elena,
Underwood Seth,
Wittenberg Andrew T.,
Xiang Baoqiang,
Yang Xiaosong,
Zeng Fanrong,
Zhang Honghai,
Zhang Liping,
Zhao Ming
Publication year - 2020
Publication title -
journal of advances in modeling earth systems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.03
H-Index - 58
ISSN - 1942-2466
DOI - 10.1029/2019ms001895
Subject(s) - climatology , environmental science , geophysical fluid dynamics , climate model , forcing (mathematics) , radiative forcing , sea surface temperature , meteorology , climate change , geology , oceanography , geography
We document the development and simulation characteristics of the next generation modeling system for seasonal to decadal prediction and projection at the Geophysical Fluid Dynamics Laboratory (GFDL). SPEAR ( S eamless System for P rediction and EA rth System R esearch) is built from component models recently developed at GFDL—the AM4 atmosphere model, MOM6 ocean code, LM4 land model, and SIS2 sea ice model. The SPEAR models are specifically designed with attributes needed for a prediction model for seasonal to decadal time scales, including the ability to run large ensembles of simulations with available computational resources. For computational speed SPEAR uses a coarse ocean resolution of approximately 1.0° (with tropical refinement). SPEAR can use differing atmospheric horizontal resolutions ranging from 1° to 0.25°. The higher atmospheric resolution facilitates improved simulation of regional climate and extremes. SPEAR is built from the same components as the GFDL CM4 and ESM4 models but with design choices geared toward seasonal to multidecadal physical climate prediction and projection. We document simulation characteristics for the time mean climate, aspects of internal variability, and the response to both idealized and realistic radiative forcing change. We describe in greater detail one focus of the model development process that was motivated by the importance of the Southern Ocean to the global climate system. We present sensitivity tests that document the influence of the Antarctic surface heat budget on Southern Ocean ventilation and deep global ocean circulation. These findings were also useful in the development processes for the GFDL CM4 and ESM4 models.