Tropical Depression Imelda has brought catastrophic flooding to coastal Texas, dropping as much as 40 inches of rain on some communities already affected by Hurricane Harvey. Bermuda barely missed the worst of Hurricane Humberto. Tropical Storm Karen, loosely organized but still a hazard, is heading toward Puerto Rico and the Virgin Islands. And Tropical Storm Lorenzo, after forming over Africa last week, is threatening to become the season’s next hurricane.
Those are just a few of the recent spate of storms currently cropping up in the Atlantic and Pacific Oceans – there are seven, as of publication.
It’s official: Hurricane season is in full swing. And every single one of those storms is a liability.
An Animated Atmosphere
Hurricane Dorian shattered what had previously been a quiet hurricane season, and it’s left enough new storms in its wake for Eric Blake, a scientist at the National Hurricane Center, to tweet that they’re “forming like roaches out there!” on Tuesday.
While it might feel like it’s difficult to remember which storm is which, experts say the number isn’t surprising.
“Things are pretty active, but that’s not necessarily unexpected,” said Kristen Corbosiero, a professor of atmospheric science at SUNY Albany. “We are coming into the time of most activity in the [Atlantic] basin.”
Corbosiero explained that the most hospitable conditions for hurricanes and other tropical storms require warm water and moist air. Right now, there’s plenty of both, as the ocean reaches its warmest temperatures in mid to late September – just as the weather is starting to cool.
“It takes longer to heat up the ocean and then it hangs onto its heat longer than the air does,” Corbosiero explained. That means that hurricane season is just reaching its peak, and favorable conditions make it more likely to be active.
Focusing on Size, and Forgetting Impact
In general, tropical storms are “becoming more impactful and certainly more dangerous. I think there’s very little debate about that,” said Corbosiero.
It’s that “impactful” element that often gets overlooked when talking about hurricanes, said Shuyi Chen, a professor of atmospheric science at the University of Washington.
Chen explained that when looking at an active season, we tend to focus on factors – the frequency of named storms, the number of high-intensity hurricanes – rather than potential impact.
And even when looking at significant storms, we define hurricanes by wind speed, not by size or distance from land – or by the accompanying rain, storm surge, and flooding, which are generally deadlier than the wind itself.
“We are not putting as much research attention or public awareness as we would like” into these other factors, Chen said.
But Imelda, which reached the Texas coastline as a tropical depression – not even a storm – has caused tremendous damage, and it’s likely to have long-term effects on still-vulnerable communities. For Chen, it’s a lesson worth learning.
“There can be a huge amount of detrimental impact with a relatively insignificant tropical storm,” she explained. When it comes to predicting the true impact on people and property, “the science is weak.”
That means that an active hurricane season, like this one, brings an amplified risk – and the need for continued vigilance. “Climatological conditions over the last several decades are certainly indicating that we should be more prepared,” Chen said.
“It looks in the near term like [the storm activity] should continue to be active through the end of the month,” Corbosiero said. But “The hurricane season goes through the end of October, if not the middle of November, so it’s always good to watch out.”
It’s not all bad news. While the path a storm will take – and the impact it will have along the way – are still hard to predict, government agencies and aid groups have gotten better at responding. They have a better idea of how to move and prepare people, and they’re more effective than ever at responding to their needs in the wake of even a catastrophic storm.
Direct Relief will continue to monitor the active season and offer help as needed. The organization is currently supporting partners in communities affected by Imelda with medicines, supplies, and necessary funding.