Investigating Predictability of DIC and SST in the Argentine Basin Through Wind Stress Perturbation Experiments

The confluence of the Malvinas and Brazil currents over the Argentine Basin give the region chaotic dynamics and severely limit potential predictability. To probe the forecast horizon for ocean surface quantities of temperature and carbon, we construct regional models of the Argentine Basin with biogeochemistry at 1/3 degrees and 1/12 degrees resolution and design a series of experiments. We add positive and negative zonal wind stress anomalies over small and large areas during a short period in different model runs. We calculate the response of the surface temperature and DIC. The 1/3 degrees model maintains predictability for up to 45 days, while the 1/12 degrees model has a shorter window of about two weeks. However, the 1/3 degrees model response is only consistent with the 1/12 degrees model for about 8 days calling into question the potential predictive skill of the coarser model at longer lead times.