What the Forecast for an Active Hurricane Season Means for the Atlantic Region

Suzana Camargo is part of a team on the leading edge of exploring and defining risks to people, property and the economy in the face of escalating extreme weather events. At Columbia University’s Lamont-Doherty Earth Observatory, she examines the impact of climate change on the frequency and severity of devastating storms like Superstorm Sandy and Hurricane Katrina. Her work has become increasingly relevant as the consequences of global warming have become more and more apparent.

Camargo’s research is extremely pertinent this week as Mumbai faces its first significant cyclone since 1948. Cyclone Nisarga made landfall at around 1 p.m. local time (3:30 a.m. ET) on Wednesday. In collaboration with Lamont scientists Adam Sobel and Chia-Ying Lee, Camargo has been studying extreme weather risk in this area of the world. Sobel and Camargo also are leading the Columbia Initiative on Extreme Weather and Climate.

In the Atlantic, forecasters are predicting above normal hurricane during the 2020-2021 hurricane season. Camargo says the possible ramifications of this busy hurricane season are complicated by the pandemic. For example, the process of evacuations would be complicated and slowed down, especially for those who rely on public transportation.

“The buses could only take so many people at one time. Between each trip, every bus would need to be completely disinfected. This will slow the process,” said Camargo. “And then, where are they going?” Evacuees are typically taken to emergency shelters, such as school gyms converted into large shared dormitories. The risk of the spreading the virus would escalate, potentially overwhelming hospitals and creating a serious health crisis.

In Mumbai, the coupled threat of the pandemic and an extreme weather event is playing out this week. Coronavirus patients were among more than 100,000 people already evacuated from low-lying coastal areas.

However, Camargo explains, in the Atlantic basin, the forecast for an active hurricane season doesn’t necessarily mean that it will be a period of very damaging storms, even though it might indeed be the case.

The seasonal forecast refers to both the number and intensity of hurricanes, but does not predict whether they will make landfall and have large impacts. She points to the 1992 hurricane season, which was not very active, but included Hurricane Andrew, a powerful and destructive Category 5 hurricane that struck the Bahamas, Florida, and Louisiana that August with significant damage and economic impacts.

Camargo says this season’s prediction is based on warmer than usual tropical Atlantic Ocean waters and the possibility of weak La Niña conditions in the equatorial Pacific — which means unusually cold ocean temperatures in that region, compared to El Niño, which is characterized by unusually warm ocean temperatures. La Niña events are typically associated with an active Atlantic hurricane season. Thus, the forecast for this season is not necessarily related to climate change.

However, Camargo says her team’s research continues to underscore the importance of creating resilient communities prepared for extreme weather associated with our changing climate.

“[C]onsidering longer time-scales and other extreme events, climate scientists are pretty certain climate change is leading to an increased risk of extreme weather events,” Camargo said, which emphasizes the importance of her research and the Columbia Initiative on Weather and Extreme Events.