A Comparison of Global Surface Air Temperature Over the Oceans Between CMIP5 Models and NCEP Reanalysis

Xian Zhu,Tianyun Dong,Wenping He,Shanshan Zhao

doi:10.3389/fenvs.2021.656779

Abstract

By utilizing eight CMIP5 model outputs in historical experiment that simulated daily mean sea surface temperature (SST) and NCEP reanalysis data over 12 ocean basins around the world from 1960 to 2005, this paper evaluates the performance of CMIP5 models based on the detrended fluctuation analysis (DFA) method. The results of National Centers for Environmental Prediction (NCEP) data showed that the SST in most ocean basins of the world had long-range correlation (LRC) characteristics. The DFA values of the SST over ocean basins are large in the tropics and small in high latitudes. In spring and autumn, the zonal average DFA of SST are basically distributed symmetrically in the Northern and Southern Hemispheres. In summer, the zonal average values of DFA in the Northern Hemisphere are larger than those in the southern hemisphere, and vice versa in winter. The performance of HadGEM2-AO, CNRM-CM5, and IPSL-CM5A-MR are all relative well among the eight models in simulating SST over most regions of the global ocean.

Highlights

Climate models and Earth system models that consider complex geo-bio-chemical processes are important tools for projecting future climate change (Zeng et al, 2008; IPCC, 2013; Prinn, 2012)
The zonal average detrended fluctuation analysis (DFA) values of IPSL-CM5A-MR and HadGEM2-Arctic Ocean (AO) had a meridional variation characteristic, which was close to National Centers for Environmental Prediction (NCEP)
The DFA value of daily mean sea surface temperature (SST) over the years showed that the DFA values of DAT is relatively large in tropical regions, especially in the equatorial Central and Eastern Pacific

Summary

INTRODUCTION

Climate models and Earth system models that consider complex geo-bio-chemical processes are important tools for projecting future climate change (Zeng et al, 2008; IPCC, 2013; Prinn, 2012). A great number of studies have confirmed that the current CMIP5 models have good ability to simulate global climate, and the results of these models can be used to project the characteristics of future global climate change. These evaluation methods mainly consider the statistical differences between the model simulations and the observation, but lack the comparison of the observation data and the simulation data in the sense of dynamic characteristics. Based on the DFA method, this paper evaluates the performance of eight CMIP5 coupled models on the daily mean sea surface temperature (SST) over ocean, indicating the shortcomings of the models on SST, and the similarities and differences among the models. We calculated the area-averaged DFA indexes in each ocean basin for NCEP and model output daily temperatures, the area-averaged DFA indexes were compared to show the differences between the NCEP and model outputs

METHOD

DISCUSSION AND CONCLUSION

DATA AVAILABILITY STATEMENT