A near‐future, 2 K warming climate simulation comprising over 3,000 years of ensemble simulations was performed using 60 km global and 20 km regional atmospheric models. Even in the +2 K climate, indices of extreme precipitation and dryness increased significantly in the extratropics compared with the historical climate. Mean precipitation increases in the rainy season and decreases in the dry season, indicating that the seasonal precipitation range becomes amplified with global warming. The intensification of precipitation and dryness from +2 K to +4 K was also robust in the mean for climatological wet and arid regions. Around Japan, which was classified as a wet region, the regional atmospheric model predicts that the extreme hourly precipitation in the future climate becomes more extreme on hot days, but slightly weaker on cold days. This extreme precipitation has a high sensitivity to air temperature exceeding 7% K^–1.

The Mirai Indian Ocean cruise for the Study of the Madden-Julian oscillation (MJO)-convection Onset (MISMO) was a field experiment that took place in the central equatorial Indian Ocean during October–December 2006, using the research vessel Mirai, a moored buoy array, and landbased sites at the Maldive Islands. The aim of MISMO was to capture atmospheric and oceanic features in the equatorial Indian Ocean when convection in the MJO was initiated. This article describes details of the experiment as well as some selected early results. Intensive observations using Doppler radar, radiosonde, surface meteorological measurements, and other instruments were conducted at 0°, 80.5°E, after deploying an array of surface and subsurface moorings around this site. The Mirai stayed within this buoy array area from 24 October through 25 November. After a period of stationary observations, underway meteorological measurements were continued from the Maldives to the eastern Indian Ocean in early December. All observatio... The Mirai Indian Ocean cruise for the Study of the Madden-Julian oscillation (MJO)-convection Onset (MISMO) was a field experiment that took place in the central equatorial Indian Ocean during October–December 2006, using the research vessel Mirai, a moored buoy array, and landbased sites at the Maldive Islands. The aim of MISMO was to capture atmospheric and oceanic features in the equatorial Indian Ocean when convection in the MJO was initiated. This article describes details of the experiment as well as some selected early results. Intensive observations using Doppler radar, radiosonde, surface meteorological measurements, and other instruments were conducted at 0°, 80.5°E, after deploying an array of surface and subsurface moorings around this site. The Mirai stayed within this buoy array area from 24 October through 25 November. After a period of stationary observations, underway meteorological measurements were continued from the Maldives to the eastern Indian Ocean in early December. All observatio...

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This paper describes the formation mechanism of morning maximum in the diurnal cycle of precipitation, at the Strait of Malacca under a calm condition, with a nonhydrostatic mesoscale numerical model and ship-based observational data. The morning precipitation peak at the strait is induced by the convergence of two cold outflows that have been produced by the precipitation systems in the previous evening over Sumatra and the Malay Peninsula. The outflows converge at the Strait of Malacca around midnight; a new precipitation system is thus generated and reaches its peak in the early morning. Sensitivity experiments using the numerical model suggest that the timing and position of the morning precipitation peak are affected by the width of the strait. In the case of the Strait of Malacca, its width favors the formation of the morning precipitation system around the center of the strait, which explains why its diurnal cycle of precipitation can be observed much clearer than those in other coastal areas over the Maritime Continent.