Precipitation and circulation patterns of Southern Hemisphere monsoons are investigated in Coupled Model Intercomparison Project's phase 5 simulation for mid-Holocene and future climate scenario rcp8.5. These two experiments show increased seasonality and change of the inter-hemispheric thermal contrast in austral summer relative to reference pre-industrial climate, therefore they are useful tools to investigate monsoon dynamic response to different forcings. While monsoons are stronger in the Northern Hemisphere in mid-Holocene simulations, they are weaker and narrower in the Southern Hemisphere. On the other hand, Southern Hemisphere monsoons show a tendency toward intensification and expansion in the future global warming scenario. A decomposition of the moisture budget into thermodynamic and dynamic contributions suggests that the weakening of Southern Hemisphere monsoon in the past is due to the weakening of the mean atmospheric flow in austral summer: the dynamic component of the moisture budget has therefore a drying effect over land monsoons. On the other hand, under global warming the general tendency at both global and local scale is the partial compensation between the thermodynamic and dynamic terms which results in a weak response of the monsoons to future forcing. The degree to which thermodynamic and dynamic components compensate each other represents one of the most important source of uncertainty on future projection on monsoons.