[1] The Madden‐Julian Oscillation (MJO) is the dominant mode of intraseasonal variability in the tropical atmosphere. This study examines the evolution of the hydrologic regime from before the onset of the MJO (pre‐onset period) to the MJO onset period, using deuterated water vapor (HDO) measurements from the Tropospheric Emission Spectrometer (TES) and from ground‐based stations. Ground‐based ...

AMERICAN METEOROLOGICAL SOCIETY | 425 W eather prediction is typically concerned with lead times of hours to days, while seasonal-tointerannual climate prediction is concerned with lead times of months to seasons. Recently, there has been growing interest in “subseasonal” forecasts—those that have lead times on the order of weeks (e.g., Schubert et al. 2002; Waliser et al. 2003; Waliser et al. ...

While no significant long-term trend in the propagation speed of Madden-Julian Oscillation (MJO) boreal winter is found during past decades, pronounced year-to-year variability MJO phase illustrated by analyzing a century-long record data set. During winters when fast observed, exhibits much larger zonal-scale than that with slow propagation. A broader extension circulation effectively induces ...

Abstract Recent observations have indicated significant modulation of the Madden Julian Oscillation (MJO) by phase stratospheric Quasi-Biennial (QBO) during boreal winter. Composites MJO show that upper tropospheric ice cloud fraction and water vapor anomalies are generally collocated, an eastward tilt with height in exists. Through radiative transfer calculations, it is shown clouds a stronger...

The intraseasonal variability of SST associated with the passage of the Madden–Julian oscillation (MJO) is well documented; yet coupled model integrations generally underpredict the magnitude of this SST variability. Observations from the Improved Meteorological Instrument (IMET) mooring in the western Pacific during the intensive observing period (IOP) of the Tropical Ocean Global Atmosphere C...

Abstract. The Madden–Julian oscillation (MJO) is the main controller of weather in tropics on intraseasonal timescales, and recent research provides evidence that quasi-biennial (QBO) influences MJO interannual variability. However, physical mechanisms behind this interaction are not completely understood. Recent studies normal-mode structure indicate contribution global-scale Kelvin Rossby wav...

Using 16 years of NCEP–NCAR reanalysis data on the 200-mb surface, it is shown that in the deep Tropics, the horizontal transient eddy momentum flux accelerates the zonal mean zonal wind. This acceleration is mainly due to transient eddies of intraannual and interannual timescales, and to those associated with the Madden– Julian oscillation (MJO). The interannual timescale eddy fluxes are domin...

Basinwide convective anomalies over the IndianOcean (IO) associated with theMadden–Julian oscillation (MJO) sometimes propagate eastward and reach the west Pacific (WP), but sometimes do not. Long-term observations and reanalysis products are used to investigate the difference between the propagating and nonpropagating MJO events. IO convection onset events associated with the MJO are grouped i...

Carbon dioxide (CO(2)) is the most important anthropogenic greenhouse gas in the present-day climate. Most of the community focuses on its long-term (decadal to centennial) behaviors that are relevant to climate change, but there are relatively few discussions of its higher-frequency forms of variability, and none regarding its subseasonal distribution. In this work, we report a large-scale int...

This paper describes a large cyclonic gyre that lasted several days in the northwest Pacific during July 1988. Cyclonic winds at 850 hPa extended beyond the 2000-km radius with a radius of maximum winds of 700– 800 km. The gyre exhibited clear skies within and north of its center. Active convection extended 4000 km in longitude to its south. The Madden–Julian oscillation (MJO) was in its active...