TITLE:
Antarctic Sea Ice Concentration in the Brazilian Earth System Model Simulations
AUTHORS:
Fernanda Casagrande, Elisângela Finotti, Ronald Buss de Souza, Regiane Moura, Noeli Franchi Leonardo
KEYWORDS:
Southern Ocean, Climate Models, Satellite, CMIP5 Simulations, Climate Validation
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.11 No.9,
September
1,
2023
ABSTRACT: Sea ice is an important and complex component of the Earth’s system,
acting as both an indicator and an amplifier
of climate change. Here, we investigated
the ability of the Brazilian Earth System Model (BESM-OA2.5) and four state-of-the-art climate models
participating in the fifth phase of the Coupled Model Intercomparison Project, Version 5 (CMIP5) to represent the Antarctic Sea Ice Concentration (SIC) seasonal cycle. We validated the sea ice
model’s performance using satellite data
from 1980 to 2005 and calculated the skill and RMSE of each model.
BESM-OA2.5 results for melt-freeze transitions in the Southern Ocean are
consistent with CMIP5 models and satellite data. In February, when the sea ice reaches its annual minimum, the BESM-OA2.5 has the best fit among the models. However, in September, when the Antarctic sea ice reaches its annual maximum, the SIC
simulated by BESM-OA2.5 indicated the largest area covered by ice
compared to satellite, particularly on the Polar Front. Similar results were
found in the CMIP5 models evaluated here. We suggest that the large bias
simulated in the Polar Front is related to the
inability of the sea ice model to represent the complex ocean-atmosphere-sea
ice interactions. The subject is considered a hot topic in climate change studies and lacks conclusive answers.