Atmosphere‐ocean coupled processes in the Madden‐Julian oscillation. (26th November 2015)

• Record Type: Journal Article
• Authors: DeMott, Charlotte A.; Klingaman, Nicholas P.; Woolnough, Steven J.
• Is Part Of: Reviews of geophysics. Volume 53:Number 4(2015:Dec.)
• Page Start: 1099
• Page End: 1154
• Publication Date: 2015-11-26
• Subjects: Madden‐Julian oscillation -- air‐sea interaction -- coupled modeling -- surface fluxes -- upper ocean -- tropical convection; Geophysics -- Periodicals; 550.5
• DOI: 10.1002/2014RG000478
• Languages: English
• ISSNs: 8755-1209

Abstract

Abstract: The Madden‐Julian oscillation (MJO) is a convectively coupled 30–70 day (intraseasonal) tropical atmospheric mode that drives variations in global weather but which is poorly simulated in most atmospheric general circulation models. Over the past two decades, field campaigns and modeling experiments have suggested that tropical atmosphere‐ocean interactions may sustain or amplify the pattern of enhanced and suppressed atmospheric convection that defines the MJO and encourage its eastward propagation through the Indian and Pacific Oceans. New observations collected during the past decade have advanced our understanding of the ocean response to atmospheric MJO forcing and the resulting intraseasonal sea surface temperature fluctuations. Numerous modeling studies have revealed a considerable impact of the mean state on MJO ocean‐atmosphere coupled processes, as well as the importance of resolving the diurnal cycle of atmosphere‐upper ocean interactions. New diagnostic methods provide insight to atmospheric variability and physical processes associated with the MJO but offer limited insight on the role of ocean feedbacks. Consequently, uncertainty remains concerning the role of the ocean in MJO theory. Our understanding of how atmosphere‐ocean coupled processes affect the MJO can be improved by collecting observations in poorly sampled regions of MJO activity, assessing oceanic and atmospheric drivers of surface fluxes, improving the representation of upper ocean mixing in coupled model simulations, designing model experiments that minimize mean state differences, and developing diagnostic tools to evaluate the nature and role of coupled ocean‐atmosphere processes over the MJO cycle. Key Points: Tropical cloudiness and wind variations on 30–70 day timescales impact the upper ocean The upper ocean response modulates heat and moisture fluxes to the atmosphere Understanding the 30–70 day ocean‐atmosphere feedbacks remains challenging