title: Influences of volcano eruptions on Asian Summer Monsoon over the last 110 years.
abstract: Asian summer monsoon (ASM) precipitation is the primary water resource for agriculture in many Asian countries that have experienced rapid economic growth in recent decades, thus implying the necessity for further investigations on both the internal variability of the ASM and the influence of external factors on the ASM. Using long-term high-resolution (0.5° × 0.5°) observed precipitation data, contrary to previous studies on inter-annual timescale, we showed that over the last 110 years, volcanic eruptions have influenced ASM variations on an inter-decadal timescale via teleconnections with the Atlantic Multi-decadal Oscillation (AMO). This relationship was also confirmed by Coupled Model Intercomparison Program Phase 5 (CMIP5) model simulations. During the active volcanic eruption periods (1901-1935 and 1963-1993), significantly lower ASM precipitation was observed compared with that during the inactive volcanic eruption period (1936-1962). We found that during active volcanic eruption periods, which correspond to a negative AMO state, there is an anomalously weakened Walker circulation over the tropical Pacific that transports less moisture to the ASM region and subsequently reduces ASM precipitation. This new finding may help improve decadal predictions of future changes in the ASM.
authors.affiliation: Key Laboratory of Virtual Geographic Environment, Ministry of Education; State key Laboratory of Geographical Environment Evolution, Jiangsu Provincial Cultivation Base; School of Geography Science, Nanjing Normal University, Nanjing, 210023, China.|Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, 210023, China.|Climate System Research Center, Department of Geosciences, University of Massachusetts, Amherst, 01003, United States.
authors.forename: Liang
authors.initials: L
authors.lastname: Ning
authors.affiliation: Key Laboratory of Virtual Geographic Environment, Ministry of Education; State key Laboratory of Geographical Environment Evolution, Jiangsu Provincial Cultivation Base; School of Geography Science, Nanjing Normal University, Nanjing, 210023, China.|Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, 210023, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Liu
authors.affiliation: Key Laboratory of Virtual Geographic Environment, Ministry of Education; State key Laboratory of Geographical Environment Evolution, Jiangsu Provincial Cultivation Base; School of Geography Science, Nanjing Normal University, Nanjing, 210023, China.|Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, 210023, China.
authors.forename: Weiyi
authors.initials: W
authors.lastname: Sun