Projecting changes in extreme rainfall from three tropical cyclones using the design-rainfall approach

Area of Science:

• Climatology
• Extreme Weather Events
• Tropical Cyclones

Background:

• Eastern North Carolina (ENC) has experienced severe tropical cyclones causing extensive flooding and damage over the last 25 years.
• Historical climate data indicate a rising trend in extreme rainfall event frequency and intensity across the eastern U.S., a trend expected to persist.
• These changes pose significant risks to coastal regions like ENC.

Purpose of the Study:

• To explore and quantify potential changes in extreme rainfall associated with tropical cyclones in ENC from 2025 to 2100.
• To assess the projected impact of climate change on rainfall intensity and frequency for future tropical cyclone events in the region.

Main Methods:

• Utilized dynamically downscaled climate projections to analyze changes in extreme rainfall frequencies (return periods).
• Focused on three specific tropical cyclone scenarios to model future rainfall patterns.
• Employed an approach based on relative changes in future extreme rainfall frequencies.

Main Results:

• Projected local maximum rainfall intensities could increase by up to 168% by 2100.
• Widespread regional increases in total rainfall are projected to reach up to 44%.
• The projected intensity of future events is comparable to the most extreme rainfall events observed in the U.S. in the early 21st century.

Conclusions:

• Future tropical cyclones in ENC may bring significantly more intense rainfall than previously projected.
• The study suggests that the extreme rainfall intensities predicted for the future may already be occurring.
• These findings highlight the urgent need for adaptation strategies to address escalating flood risks in ENC.