You are here:
Climate change impacts on extreme events in the United States: an uncertainty analysis
Citation:
Climate change impacts on extreme events in the United States: an uncertainty analysis. CLIMATIC CHANGE. Springer Netherlands, , Netherlands.
Impact/Purpose:
Paper part of CIRA project in special journal issue
Description:
Extreme weather and climate events, such as heat waves, droughts and severe precipitation events, have substantial impacts on ecosystems and the economy. However, future climate simulations display large uncertainty in mean changes. As a result, the uncertainty in future changes of extreme events, especially at the local and national level, is large. In this study, we analyze changes in extreme events over the United States (US) in a 60-member ensemble simulations of the 21st century with the Massachusetts Institute of Technology (MIT) Integrated Global System Model Community Atmosphere Model (IGSM-CAM). Four values of climate sensitivity, three emissions scenarios and five initial conditions are considered. The results show a general intensification of extreme hot days and extreme precipitation events over most of the US. The number of rain day per year increases over the Great Plains but decreases in the northern Pacific Coast and along the Gulf Coast. Extreme cold days temperature increases, especially over the northern parts of the US. As a result, the number of frost days per year decreases over the entire US and the frost-free zone expands northward. Under a reference emissions scenario with no climate policy, changes in extreme events reach dangerous levels, especially for large values of climate sensitivity. On the other hand, the implementation of a stabilization scenario with a total radiative forcing of 4.5 W/m2 by 2100, drastically reduces the changes in extremes, even for the highest climate sensitivity considered.
