Impacts of socio-economic and climate changes on water, food, bioenergy,
land use, and ecosystems
Abstract
Future socio-economic and climate changes can profoundly impact water
resources, food production, bioenergy generation, and land use, leading
to a broad range of societal problems. In this study, we performed
future projections by using a land integrated model, MIROC-INTEG-LAND,
that considers land surface physics, ecosystems, water management, crop
growth, and land use, under various socio-economic scenarios (Shared
Socio-economic Pathways, SSPs). Under the sustainability scenario
(SSP1), demands for food and bioenergy are kept low, so that the
increase in cropland areas for food and bioenergy are suppressed. On the
contrary, in the middle of the road and regional rivalry scenarios (SSP2
and SSP3), cropland areas are projected to increase due to high demand
for food and bioenergy. The expansion of cropland areas is projected to
increase the water demand for irrigation and CO2
emissions due to land use change. MIROC-INTEG-LAND simulations indicate
that the impacts of the CO2 fertilization effect and
climate change on crop yields are comparable, with the latter being
greater than the former under climate scenarios with high greenhouse gas
concentrations. We also show that the CO2 fertilization
effects and climate change play important roles in changes in food
cropland area, water demand for irrigation, and CO2
emissions due to land use change. Our results underscore the importance
of considering Earth-human system interactions when developing future
socio-economic scenarios and studying climate change impacts.