Climate change makes allergy season longer

By MICHAEL SOL WARREN (NJ Spotlight) and AYURELLA HORN-MULLER (Climate Central)

Kyle Reeves was out walking with a friend last week at Weequahic Park in Newark’s South Ward. It was a warm, dry and breezy day in a lull between the peak of tree pollen season and the peak of grass pollen season.

About as good as it gets for a person with pollen allergies, like Reeves.

“Today is a good day. My eyes are only running a little bit. They’re not itchy. I’m not sneezing,” said Reeves, an Elizabeth resident. “So today, I’m in good spirits.”

But not every day can be a good day. And when the pollen count rises, Reeves gets hit hard.

“It’s very miserable,” Reeves said. “Sometimes, you might get the shortness of breath, depending on the allergies and the pollen. Your eyes burn, you sneeze all day. It’s brutal.”

As pollution traps heat and lengthens growing seasons for weeds and trees, allergy seasons are getting longer in New Jersey and across much of the nation. And that same carbon pollution is helping plants produce more pollen. That’s bringing more irritation to allergy sufferers like Reeves and damaging public health by inflaming asthma and other conditions.

LaTonya Sharp, a lifelong Newark resident, said she relates. And she’s noticed that her allergies seem to be persisting longer through the year.

“It doesn’t even matter if the season is changing,” she added. “It just seems like lately, it’s just all the time.”

The analysis

And scientific analysis bear that out, with the pollen season expanding in most of New Jersey by a week to a month, according to an analysis by Climate Central in partnership with NJ Spotlight News. That analysis looked at weather station data for nine communities dating to 1970. By examining the average number of days between the last spring freeze and the first fall frost at each location each year, Climate Central found the pollen season grew in eight of them by between eight and 28 days.

Atlantic City’s pollen season starts six days sooner now and runs 15 days longer than it did in 1970, according to that data analysis. Flemington’s season starts more than two weeks earlier and lasts 28 days longer. In Newark, the pollen flies four days sooner and 10 days longer. In only one case, Millville, was allergy season found to be growing shorter.

Dr. Leonard Bielory, an allergist in Springfield who is the director of the Center for Aerobiological Research Studies (CAReS) at Kean University, where he studies allergies, said New Jersey’s allergy season usually follows a set pattern: tree pollen in the spring, followed by grass through the summer, ending with ragweed in the fall.

“If you don’t have frost, the plants don’t die and therefore you have a longer season,” Bielory said.

Global warming is fueled by ballooning levels of greenhouse gases in the atmosphere. The most prevalent of these is carbon dioxide, which plants rely on for photosynthesis. So as carbon dioxide concentrations rise, plants are producing more pollen, according to University of Michigan atmospheric scientist Yingxiao Zhang.

Pollen could double by 2100, study finds

A doctoral candidate, Zhang co-authored a 2022 study with atmospheric scientist Allison Steiner that found that total pollen across the U.S. could double by 2100 if pollution emissions remain high.

Their modeling also found that by the close of the century, the pollen seasons for 15 types of trees that cause allergies in the Northeast will dovetail as temperatures and carbon dioxide concentrations rise, making the region one of the hardest-hit nationwide by that pollen increase.

“One reason is because there’s a lot more plant species there, which will have more overlap in their pollen seasons and increased total pollination,” Zhang said.

By comparing pollen production from the end of the century with recent pollen levels, the modeling projected that based on rising temperature and precipitation, total pollen production could at least increase by 23% over New Jersey by 2100, with oak and cypress pollen becoming more dominant.

Zhang’s research indicates that the changes will lead to more prevalent allergies that will affect populations not currently dealing with them.

About 30% of the world’s population is impacted by seasonal allergies, and the economic impact from conditions like these include both health care costs and absences from work and school. This figure will rise as temperatures and carbon dioxide levels increase worldwide and exacerbate those health conditions.

‘More people becoming allergic’

“There will be more people becoming allergic to pollen,” Zhang said. “It’s not only like people that already have allergies or more severe symptoms to the pollen allergy.”

All of this is bad news for people like Mark Clarke, who said he moved to Newark from the Bronx nearly four years ago and developed allergies around that time.

“My eyes get real burny, like watery,” Clarke said. “Sometimes it turns into like a sinus headache. Like I’ve got a headache for a minute where I can’t even be out in a bright light. So I … have to have it shaded until it goes away. I kind of wait it out.”

For people with severe allergies, or with compounding conditions like asthma, the threat goes beyond just being uncomfortable. It can even be deadly.

Amir Sapkota, of the University of Maryland, led a study published in 2020 that identified a connection between early onsets of spring and increases in asthma-related hospitalizations in Maryland.

The study found that earlier spring pollen seasons drove asthma hospitalizations up 17% because different trees propagated their pollen loads all at once. Sapkota, an environmental health scientist, said he suspects it repeats during fall ragweed season and expects to see the same relationship in New Jersey.

“Climate change is impacting people. In our backyard, in our community, right now,” Sapkota said.

The health burdens associated with extended pollen seasons aren’t felt equally, either — allergies and asthma tend to be disproportionately higher for Black and Latinxcommunities across the U.S.

“It’s affecting kids in our neighborhood, in our family, and our neighbors,” Sapkota said. “There’s so many ways it’s doing that, and this is an example of that.”

Sapkota’s data doesn’t reveal the impacts on those suffering from extended, intensified pollen seasons without requiring hospitalization.

“What we are looking at is obviously the worst of the worst, right? So these are people who actually are living with asthma and their asthma gets so bad, they end up in the emergency room, they end up in the hospital,” he said. “So this is sort of like just the tip of the iceberg.”

Treatment exists for allergy sufferers, from over-the-counter antihistamines to immunotherapy, but the costs can make them inaccessible for lower-income households.

Allergies, asthma cost the U.S. billions

Managing allergies triggered by seasonal changes costs Americans up to $4 billionevery year. And more than $80 billion is spent annually by those living with asthma in medical expenses, missed work and school days, and in extreme cases, death.

“Imagine having difficulty breathing, off an asthma attack at two to four in the morning, so you awaken with an inability to breathe. Just think about how traumatizing that is,” said allergist Dr. John Oppenheimer, head of research at Pulmonary and Allergy Associates.

It’s not just asthma — research demonstrates the overall impact and quality of life in children with allergic rhinitis includes learning impairment and sleep disruption. “It really has downstream effects,” Oppenheimer said.

Cities like Newark are particularly vulnerable. Ragweed, a prolific pollen producer, is often among the first plants to take root in the disturbed soils of urban areas. Meanwhile, air pollution from high car and truck traffic, plus heavy industry, cause city residents to endure higher rates of asthma and respiratory diseases.

This isn’t lost on Newark resident Clarke.

“When you go further up in the hills, the air is much cooler, and the air is not so dense, I think it’s a lot better for you to breathe,” Clarke said. “But when it’s so condensed here, and there’s so much people around, it kind of contributes.”

— This story was produced through a collaboration between Climate Central and NJ Spotlight News. NJ Spotlight News senior correspondent Brenda Flanagan contributed reporting. Climate Central data analyst Kaitlyn Weber contributed data reporting.