Windstorms in a Warmer World
Windstorms associated with intense synoptic-scale cyclones are an important natural hazard in the northeastern US. Here, we provide a preliminary assessment of their response to global warming using a combination of storyline-based pseudo-global warming experiments and long-term transient simulations.
The US northeastern states and adjacent Canadian provinces have a population of over 130 million. The 10 most powerful cold-season windstorms during 1979-2018 caused > 34 billion USD in damage in this area. Thus, cold-season windstorms represent an important and potentially changing geophysical hazard in this region. Understanding how they may evolve in a warmer climate is important to informing measures to enhance resilience.
Alberta Clippers and Colorado Lows dominate the cyclone types responsible for historical windstorms in the Northeastern USA and thus are sampled in PGW simulations. PGW simulations show they will be only marginally intensified under global warming. However, a transient simulation (2010-2050), also with the WRF model nested in the MPI-LR for a high-emission scenario, suggests an increasing role for tropical cyclones that undergo transition to extratropical cyclones in generating future windstorms. This implies an increase in the co-occurrence of other hazards (e.g. storm surge and/or heavy precipitation) and reinforces the value of combining information from both PGW experiments and transient simulations when seeking to quantify the future risk associated with extreme events under changing climate.