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Spatial distribution of decadal average SPEI in the 2030s, 2050s, and 2080s in (a) RCP 2.6 Scenario; (b) RCP 4.5 Scenario; (c)RCP 8.5 Scenario. • Climate change would affect the extent and global distribution of drought. • Global drought would be more aggravated in RCP 8.5 scenario. • Significant increase of ET 0 would occur in most grain producing countries. Drought is the most widespread and most influential natural disaster in the world, especially a threat to agricultural production. In future climate scenarios, the meteorological elements such as precipitation and temperature in each region will change, which will affect the distribution and characteristics of global drought in the future. In this paper, the global drought propensity was evaluated by reformulated Standardized Precipitation Evapotranspiration Index (SPEI-PM) based on Penman-Monteith equation in three future climate scenarios (RCP2.6, RCP4.5 and RCP8.5) of 9 General Circulation Models (GCMs). Mann-Kendall (MK) trend test and empirical orthogonal function (EOF) analysis were used to assess the spatial-temporal distribution and evolution characteristics of the future global drought. Taking reference evapotranspiration (ET 0) of crops as the index, potential effects of global drought on agricultural water use were assessed. The results showed that under the influence of the changes of future temperature, precipitation and other meteorological factors, the global drought has presented regional difference characteristics. In three climate scenarios, the trend of severe drought was detected in Africa, North America, South America and Oceania in three climate scenarios. Spatial distribution of SPEI is consistent and intensified drought was detected in southern, northern and northeast of Africa in three decades in all scenarios. EOF analysis showed that there were more positive time coefficients in RCP8.5 scenario than other scenarios, then parts of South America and Africa would face intensified drought in all climate scenarios. The evolution of future global drought would pose a threat on global water use for agricultural production. The annual average ET 0 of three decades in major grain producing countries would be on the rise compared to the baseline (1976–2005), among which RCP8.5 scenario was most obvious. Large increase rate of ET 0 would occur in Ukraine, Turkey, Russia and Canada in the 2080s in three scenarios. In the future, major grain producing countries would face serious threats of drought, which would pose a great challenge to regional agricultural water use. The study will provide forward-looking information to alleviate the adverse effects of drought on agricultural water use. [ABSTRACT FROM AUTHOR]

• Phytophthora cinnamomi and soil moisture affected Quercus suber performance. • The inoculum density required to cause disease increased at lower soil moisture. • An average drier climate might imply a slower advance of the disease. • On the contrary, more frequent extreme rain events might favor the disease. Climate change and exotic pests and pathogens are causing alarming forest declines worldwide. However, we still lack a comprehensive understanding of how damage caused by exotic pests and pathogens might vary under the different scenarios of water availability imposed by a changing climate, particularly in water-limited forests as those that occupy Mediterranean areas. In this paper we aimed to experimentally analyse the interactive effects of the aggressive exotic pathogen Phytophthora cinnamomi and climate change-related reductions in soil moisture on seedling performance of the Mediterranean host Quercus suber. We conducted a full-factorial greenhouse experiment where the physiology and growth of Q. suber seedlings was measured in soils with different combinations of P. cinnamomi inoculum density (0, 30, 60 and 120 colony forming units per gram of dry soil) and soil moisture (15%, 40%, 50% and 100% soil water holding capacity) simulating different invasion and climate change scenarios. We found additive effects of P. cinnamomi and drought on Q. suber performance aboveground, although these effects were not always negative. In fact, seedlings showed a compensatory physiological response to P. cinnamomi infection by increasing their net photosynthetic rates. Our results also supported important interactive effects of pathogens and soil moisture on belowground performance. Thus, the inoculum density in the soil required to cause significant root damage in experimental seedlings decreased as soil moisture increased. From a climate change perspective, these results suggest that an average drier climate might imply sub-optimal conditions for P. cinnamomi infections allowing for a slower advance of the disease in invaded areas. However, this effect will be modulated by the also predicted more frequent extreme climatic events. A higher frequency of extreme rain events that saturate the soil might be particularly beneficial for P. cinnamomi , boosting its soil density beyond any possible response capacity of susceptible hosts. [ABSTRACT FROM AUTHOR]