Substantial Sea Surface Temperature Cooling in the Banda Sea Associated with the Madden‐Julian Oscillation in the Boreal Winter of 2015

The Madden-Julian Oscillation (MJO; Madden & Julian, 1972) is the leading mode of intraseasonal variability in the tropics that has significant impacts on the global weather-climate system (Zhang, 2005, 2013). Its planetary-scale convective envelope propagates eastward over the Maritime Continent (MC) area at about 5 m s. The MJO signal has a notable seasonal variability (Zhang & Dong, 2004), and is strong during the northwesterly monsoon season (Kikuchi et al., 2012). While the MJO propagates over the MC area, its convective anomaly is often centered south of the equator, with the strongest signal being found over the marginal seas (Kim et al., 2017; Ling et al., 2019; Napitu et al., 2015; Zhang & Ling, 2017).