Hurricane Idalia: the fingerprints of the Arctic climate crisis

As of 11am local time, Hurricane Idalia is barreling toward Florida as a Category 1 storm but is expected to intensify into a Category 3 cyclone before it slams into the state’s Big Bend region. 

Idalia is particularly threatening for several reasons. One, is that it tracks in some of the same footsteps as last year’s Hurricane Ian, which became the most expensive climate disaster with a price tag of US$118bn and led to 149 deaths as it ripped through Cuba and central Florida. Counties, such as Sanibel, are still reeling from infrastructure and housing loss, making the area more vulnerable to further damage from Idalia. 

Two, like Ian, Idalia has the fingerprints of climate change. Idalia is primed for what is known as rapid intensification, which means the storm’s winds increase by at least 35mph within 24h. This increases the likelihood that the storm makes landfall at a higher intensity than for what people have prepared. Consequently, a lack of sufficient preparedness can yield higher death tolls and damages. 

As typical with hurricanes, water damage is expected to have the most significant impacts with Idalia. Rainfall may amount to 8 inches, and along the Floridian coasts, storm surges could reach 7 feet in Tampa Bay and up to 12 feet farther north.  

One main reason for this rapid intensification forecast? The Gulf of Mexico is boiling—almost! In late July, water off the Florida Keys tipped 101.19F/38.43C with other areas also measuring above 100F. To give perspective, NOAA reports the average water temperature in these parts to be between 73F and 88F (23C and 31C). Such excessively warm waters are key to the rapid intensification of more powerful storms.  

Although hurricanes may originate in the tropics, Arctic warming is one of the main contributors to their power. As the Arctic absorbs more solar radiation and loses snow and ice coverage, it loses the ability to act as a core component of the planet’s cooling system. For each degree (Centigrade) that the planet warms, the atmosphere can hold 7% more moisture. This moisture, especially when combined with warmer oceans, drives stronger tropical cyclones (IPCC AR6 WG1, 2021). Learn more about the Arctic and global risks, such as extreme weather here.

Twitter.com/NWSTampaBay is tracking the storm with updates in English and Spanish. 

Twitter.com/NWSTampaBay está rastreando la tormenta con actualizaciones en inglés y español. 

Image credit: The National Guard, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0>, via Wikimedia Commons