Strategic Environmental Research and Development Program (SERDP)
The Strategic Environmental Research and Development Program (SERDP) is the Department of Defense’s environmental science and technology program.
Through a SERDP grant awarded in 2015, Dr. Kenneth Kunkel of NCICS and his project team are engaged in a five-year project to develop a framework for incorporating the potential impact of future climate change into the Intensity-Duration-Frequency (IDF) values of heavy precipitation.
The underlying basis for the project is the robust projection that global warming, driven by increasing greenhouse gas concentrations, will result in an increase in atmospheric water vapor concentrations and, in turn, the potential for more intense precipitation. Actual changes in IDF values will result from both changes in water vapor concentrations and the number and intensity of heavy precipitation-producing storm systems. This project will evaluate these two components to determine the potential impact for a wide range of frequencies and durations used by civil engineers, and provide a means for adjusting and delivering the IDF values and uncertainty estimates.
The primary source of information for determining future changes will be the climate simulations available from the Coupled-Model Intercomparison Project Phase 5 (CMIP5). These simulations will be analyzed for future changes in water vapor concentration and weather system occurrence and validated through comparisons with historical observations.
Use of the existing IDF curves is likely to lead to under-design of runoff control structures—and associated increased flood damages—in most regions because of the high likelihood of increases in the intensity of heavy rainfall. The adjusted IDF curves to be produced in this project will incorporate the best scientific knowledge available to properly evaluate this future risk and make appropriate decisions about design of structures. The long-term benefit will be increased resilience to flooding and avoidance of this threat to military readiness.