In general, it is recognised that global climate change will intensify the water crisis. Global warming intensifies the water cycle and exacerbates the water problems on our planet. In humid regions the precipitation increases and in arid and semi-arid regions the precipitation is decreasing.

Canadian studies of the impacts of climate change on the hydrologic cycle point to significant changes to streamflows, lake levels, water quality, groundwater infiltration, and patterns of groundwater recharge and discharge. These impacts will vary across the country, due to regional differences in climate changes, hydrological characteristics, water demand and management practices.

Given that the hydrologic cycle is very sensitive to changes in temperature, precipitation and evaporation, any significant changes in climate patterns can cause serious difficulties in attempting to manage water resources.

Adapted from Pollution Probe's Mainstreaming Climate Change in Drinking Water Source Protection Planning in Ontario Primer.