The 2020 Atlantic hurricane season officially begins in four days, although we’ve already had our first named storm – Tropical Storm Arthur. Tropical cyclones are among nature’s most powerful and destructive phenomena, and scientists are growing more confident that the increase in Earth’s surface temperatures is impacting the intensity of tropical cyclones. A new collaborative study that further explored this hypothesis was published last month by scientists from the Center for Weather and Climate (NOAA/NCEI) and the Cooperative Insitute for Meteorological Satellite Studies at the University of Wisonsin-Madison.
While theory and climate models have long connected the trend of warming temperatures on Earth and tropical storm intensity, this study delved deeper. The study investigated nearly four decades of satellite data (about ten years more data than prior studies had looked at) and measured many different aspects of hurricanes, while also accounting for differences in data that can be caused by advances in technology over time.
In an effort to aid in hurricane planning and adaption (hurricanes are the costliest weather and climate disaster to impact the United States), the team of scientists wanted to gain higher confidence in hurricane projections for future years. The longer data period studied allowed scientists to identify statistically significant global trends and more definitive results which linked warming and hurricane intensity more strongly than before.
The scientists learned there would be a clear shift towards storms becoming major tropical cyclones (defined as a Saffir-Simpson Category 3 or higher with winds of at least 111 miles per hour). The probability of a hurricane having wind speeds with major strength increased by approximately eight percent per decade. The scientists also discovered that the North Atlantic, along the eastern seaboard of the United States would see the greatest changes with more major hurricanes.
Identifying the changes in tropical cyclone risks and understanding the factors that cause the change is imperative in taking steps toward adaptation. The next steps are to continue communicating these risks with policy makers, city planners, and emergency managers so that they are armed with the knowledge needed to make the best adaptive decisions for their cities and states.