Future changes in convective precipitation and severe weather environment in western Canada and the central U.S. Plains

Abstract

Thunderstorms are a common atmospheric phenomenon in North America that may yield extreme weather like hail, tornadoes, heavy rain, and lightning and can have significant societal and economic impacts. As global mean surface temperature has increased, regional climate models (RCMs) have been used to examine the relationship between thunderstorms and global climate change. This thesis examined this relationship using precipitation and severe weather parameter data from three model pairings produced by the North American Regional Climate Change Assessment Program (NARCCAP) over western Canada and the central U.S. Plains. Over parts of western Canada, the pairings show significant increases in convective precipitation and CAPE, suggesting increased frequency and/or intensity of thunderstorms over this region. In the central U.S. Plains, the results suggested future increases in severe thunderstorms and/or increased potential for severe thunderstorms over certain regions whereas others suggested an increase in non-severe thunderstorms due to decreased wind shear.