Investigating the relationship between the frequency of flooding over the central United States and large-scale climate

The results of this work indicate that climate variability can play a significant role in explaining the variations in the frequency of flooding over the central United States. Different climate modes are related to the frequency of flood events over different parts of the domain and for different seasons, with PNA playing an overall dominant role. Analyses related to flood events are extended to examine climate controls on heavy precipitation over the same area. We find that the variability of the Atlantic and Pacific Oceans can influence the frequency of heavy precipitation days in a manner similar to what was found for flooding. Therefore, these results suggest that the recent observed variability in the frequency of flood events and heavy precipitation over the central United States can be largely attributed to the variability in the climate system.