The sea surface temperature (SST) anomaly in the present climate shows a marked negative skewness in the equatorial eastern Indian Ocean (EEIO) during the Indian Ocean Dipole mature phase (September ~ November). The change of the SST negative skewness under global warming is explored by diagnosing the model outputs of the constant climate forcing and increasing greenhouse gas concentration (A1B run ) scenarios of the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC-AR4). The result shows that the amplitude of the negative SST skewness in EEIO is significantly weakening under global warming for most of the IPCC-AR4 model outputs. As the mean themocline in the equatorial Indian Ocean shoals significantly under global warming, the relative contribution of the horizontal and vertical advection terms in contributing to the negative skewness is further analyzed by diagnosing the mixed layer heat budget in the present and future climate simulations. It turns out that the major difference appears in the horizontal oceanic temperature advections, suggesting that the thermocline-SST feedback is not crucial in generating the skewness difference in the equatorial Indian Ocean.
關聯:
2011 American Geophysical Union (AGU) Fall Meeting,Organised by AGU,2011-12-05~09