Evaluation of a present-day climate simulation with a new coupled atmosphere-ocean model GENMOM

Abstract

Abstract. We present a new, non-flux corrected AOGCM, GENMOM, that combines the GENESIS version 3 atmospheric GCM (Global Environmental and Ecological Simulation of Interactive Systems) and MOM2 (Modular Ocean Model version 2) nominally at T31 resolution. We evaluate GENMOM by comparison with reanalysis products (e.g., NCEP2) and three models used in the IPCC AR4 assessment. GENMOM produces a global temperature bias of 0.6 • C. Atmospheric features such as the jet stream structure and major semi-permanent sea level pressure centers are well simulated as is the mean planetary-scale wind structure that is needed to produce the correct position of stormtracks. Most ocean surface currents are reproduced except where they are not resolvable at T31 resolution. Overall, GENMOM captures reasonably well the observed gradients and spatial distributions of annual surface temperature and precipitation and the simulations are on par with other AOGCMs. Deficiencies in the GENMOM simulations include a warm bias in the surface temperature over the southern oceans, a split in the ITCZ and weaker-than-observed overturning circulation.

Pliocene Model Intercomparison Project Experiment 1: implementation strategy and mid-Pliocene global climatology using GENESIS v3.0 GCM

“…Vegetation distributions and their physical attributes can be provided in multiple ways, either using prescribed data sets (Dorman and Sellers, 1989, see below), or from interactively coupled, predictive vegetation models (e.g., EVE Bergengren et al, 2001 andBIOME4 Kaplan et al, 2003;Koenig et al, 2011). The ocean can be represented either by prescribed climatological sea-surface-temperatures and sea ice, by a predictive 50-m slab diffusive mixed-layer and dynamical sea-ice model, or by a 3-D ocean GCM (Pacanowski, 1996;Zhou et al, 2008;Alder et al, 2011). The GENESIS GCM has been validated against modern climate and used extensively for paleoclimatic simulations (e.g., Thompson and Pollard, 1997;Mathieu et al, 2002;Pollard and PMIP Groups, 2000;DeConto et al, 2007 and references therein).…”

A GCM comparison of Pleistocene super-interglacial periods in relation to Lake El'gygytgyn, NE Arctic Russia

“…Vegetation distributions take the form of 27 plant biomes, including 12 plant functional types (PFTs) that represent broad, physiologically distinct classes (Kaplan, 2003). GENESIS includes options for coupling to an ocean general circulation model (Alder et al, 2011) or a non-dynamical, slab ocean model that incorporates heat transfer, calculations of sea surface temperatures (SSTs) and feedbacks operating between ocean surface and sea ice. The slab mixed-layer ocean model is used here to allow multiple simulations to be performed with and without imposed perturbations of surface ocean conditions.…”

“…All global climate simulations discussed herein were performed using the current version of the Global ENvironmental and Ecological Simulation of Interactive Systems (GEN-ESIS) global climate model (GCM) version 3.0 (Alder et al, 2011;Thompson and Pollard, 1997). GENESIS is an atmosphere, land surface, ocean, snow, sea ice, ice sheet and vegetation coupled model.…”

Reprint of: Modeling Antarctic ice sheet and climate variations during Marine Isotope Stage 31

“…Version 3 uses the NCAR CCM3 solar and thermal infrared radiation code (Kiehl et al, 1998). The ocean can be a 3-D dynamical OGCM (MOM2, as in Zhou et al, 2008 andAlder et al, 2011), but for computational efficiency here and as in most of the studies above, a 50-m mixed-layer slab ocean is used with diffusive horizontal heat transport and dynamical sea ice. Modern results with a slab ocean for version 2 are compared with observed climatology in Thompson and Pollard (1997); in particular, austral summer temperatures around the Antarctic periphery are reasonably realistic.…”