Non-stationary and climate change-informed intensity-duration-frequency (IDF) curve for the Dallas-Fort Worth metroplex, Texas, United States

Ghimire, Binita

Publication

Non-stationary and climate change-informed intensity-duration-frequency (IDF) curve for the Dallas-Fort Worth metroplex, Texas, United States

Ghimire, Binita

Date

2023-05-04

Abstract

Extreme precipitation is becoming more frequent and intense due to climate change. Nonetheless, the infrastructure design tools such as Intensity-Duration-Frequency (IDF) curves still rely on historical precipitation and stationary assumption, risking current and future urban infrastructure. This study developed IDF curves by incorporating non-stationarity trends in precipitation records and Global Climate Models (GCMs)-based precipitation ensembles for the Dallas-Fort Worth metroplex, Texas, United States. A Pro-NEVA tool was utilized to develop seven IDF curves taking historical precipitation annual maximum series for seven out of 88 stations that showed a non-stationary trend with time as a covariate. Also, 40 future climate-based IDF curves (20 GCMs × 2 RCPs) were developed for one of the DFW stations. IDF curves, constructed with historical precipitation records and under the non-stationary assumption, indicated an increase (up to 75%) in the 24-hour precipitation intensity for the 100-year return period. While only 5% of the IDF curves, constructed using projected GCM precipitation, showed an increase (up to 39%) in the 24-hour precipitation intensity for any return period. Creating and using such a climate change adaptive IDF tool for the DFW metroplex and similar urban regions could enable decision-makers to make climate-informed choices about infrastructure investments, emergency preparedness measures, and long-term planning for urban development and water resource management.