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Large ensemble pairs of high‐resolution global and regional climate simulations, which are composed of 100 members of 60 years each, make it possible to attribute changes in local‐scale heavy precipitation to historical global warming. Mountain ranges separate local climates and can modulate the impact of global warming on heavy precipitation. In the summer, Japan's Kyushu region, with mountain ranges approximately 200‐km long from south to north, receives large amounts of precipitation. Over western Kyushu, the monthly maximum daily precipitation (maxPrdaily) in July increases due to historical global warming, while the maxPrdaily is unchanged over eastern Kyushu. Moisture advection and convergence due to stationary weather fronts are primary factors causing heavy precipitation in western Kyushu and moistening due to warming increases the maxPrdaily. On the other hand, typhoons heading to Kyushu are related to heavy precipitation over eastern Kyushu. The changes in typhoons heading to Kyushu result in unchanged maxPrdaily in eastern Kyushu. Our results suggest that local‐scale mountain ranges can change synoptic‐scale disturbances causing heavy precipitation and modulate the impact of historical global warming on heavy precipitation across mountain ranges. Plain Language Summary: Global warming has already increased heavy precipitation, but the impact of global warming on heavy precipitation depends on the region. Mountain ranges separate local climates. Different synoptic disturbances cause heavy precipitation over one side of the mountain ranges. For instance, the advection and convergence of water vapor due to a stationary weather front cause heavy precipitation on the western sides of mountain ranges in the third‐largest island in Japan, while typhoons cause heavy precipitation in the eastern side of mountain ranges. Since the impacts of global warming on these synoptic phenomena are different, the changes in heavy precipitation over each side of the mountain ranges are also different. Key Points: Large ensemble simulations indicate that historical global warming has already changed the frequency of heavy precipitation in JapanLocal‐scale heavy precipitation is caused by different synoptic conditions over the western and eastern sides of mountain rangesThe contribution of global warming to the frequency of heavy precipitation depends on synoptic disturbances causing heavy precipitation [ABSTRACT FROM AUTHOR]

Rapid expansion of exotic bamboos has lowered species diversity in Japan's ecosystems by hampering native plant growth. The invasive potential of bamboo, facilitated by global warming, may also affect other countries with developing bamboo industries. We examined past (1975-1980) and recent (2012) distributions of major exotic bamboos ( Phyllostachys edulis and P. bambusoides ) in areas adjacent to 145 weather stations in central and northern Japan. Bamboo stands have been established at 17 sites along the latitudinal and altitudinal distributional limit during the last three decades. Ecological niche modeling indicated that temperature had a strong influence on bamboo distribution. Using mean annual temperature and sun radiation data, we reproduced bamboo distribution (accuracy = 0.93 and AUC (area under the receiver operating characteristic curve) = 0.92). These results infer that exotic bamboo distribution has shifted northward and upslope, in association with recent climate warming. Then, we simulated future climate data and projected the climate change impact on the potential habitat distribution of invasive bamboos under different temperature increases (i.e., 1.5°C, 2.0°C, 3.0°C, and 4.0°C) relative to the preindustrial period. Potential habitats in central and northern Japan were estimated to increase from 35% under the current climate (1980-2000) to 46%-48%, 51%-54%, 61%-67%, and 77%-83% under 1.5°C, 2.0°C, 3.0°C, and 4.0°C warming levels, respectively. These infer that the risk areas can increase by 1.3 times even under a 1.5°C scenario and expand by 2.3 times under a 4.0°C scenario. For sustainable ecosystem management, both mitigation and adaptation are necessary: bamboo planting must be carefully monitored in predicted potential habitats, which covers most of Japan.