May 23 - July 29
Climate Change Hazards: Extreme Precipitation Events & Flooding in Oklahoma’s Tribal Nations
Kristina Mazur, April Taylor, Esther Mullens, and Derek Rosendahl
What is already known:
- Flooding caused by extreme precipitation events is one of the top hazards effecting Citizen Potawatomi Nation, Choctaw Nation of Oklahoma and Chickasaw Nation.
- Climate change can lead to more extreme weather events such as extreme precipitation and flooding.
- Patterns such as the intensity, frequency, timing, and duration of extreme weather events are changing as a result of climate change.
What this study adds:
- This study provides tribal nations with future climate projections to help them prepare for and mitigate damages caused by extreme precipitation events.
- Tribal nations in the future should expect an increase in extreme rainfall events, rather than an increase in the average daily precipitation rate.
- There is reasonable confidence in extreme precipitation changes across this region; however, the 15 models displayed a range of possible outcomes.
Abstract:
Extreme weather hazards are important because they can result in the loss of life, destruction of property, and damage to the environment. It is therefore important to understand how the frequency and intensity of these hazards may change in the future due to climate change. For this study, we address extreme precipitation across Oklahoma, specifically the area which the Citizen Potawatomi Nation, Choctaw Nation of Oklahoma, and Chickasaw Nation encompass. Based on interviews with tribal emergency managers of these three nations, flooding was indicted as a particularly impactful hazard. As a result, this project develops nation-specific projections in heavy precipitation, using various metrics to quantify extremes. High-resolution (~6 km) statistically-downscaled climate model projections, from the Multivariate Adaptive Constructed Analogues (MACA) project were used to assess future changes in heavy precipitation. The results of the future projections show that the average daily precipitation rate does not change in the mid-century (2021-2051) or late-century future (2060-2090); however, heavy precipitation at higher thresholds are likely to increase over these tribal nations in Oklahoma for the same time periods. This was evident by the trends identified in frequencies of 2 inches and 4 inches per day, and 5-day accumulations exceeding 8 inches. Overall, this research will assist tribal emergency mangers in planning for and mitigating potential impacts of floods.