Improved air-sea flux algorithms
Improved air-sea flux algorithms in an ocean-atmosphere coupled model for simulation of global ocean SST and its tropical Pacific variability
Enhanced algorithm for air-sea exchange parameterisation for momentum, sensible and latent heat flux parameterisation improves the climatic simulation of global sea surface temperature (SST) distribution and its Tropical Pacific variability. Based upon analyses and summary of field programs, we constructed new algorithms for atmospheric surface momentum and scalar roughness lengths on 10-m neutral wind speeds and evaluate them against the existing expressions in the ocean-atmospheric coupled model of Australian Community Climate and Earth-System Simulator (ACCESS). The new algorithm improves simulations for mean global SST distribution, evidenced with Pearson’s correlation indices indicating corrections to a net fraction of 28 % over the global oceans. Focused on tropical Pacific, the algorithm eases the tropical SST cool tongue bias, and improves predictability of ENSO variability with better representations of standard deviation of Nino-3.4 index, especially skewness of the index for nonlinearity of ENSO variability.