Pollen and Climate Change

Allergy symptoms such as sneezing, itchy eyes, and a runny nose have been getting worse over the past few decades, and the reason may surprise you: Climate change.

Scientists have found that allergy seasons are getting longer and more severe. Human-caused climate change is the “dominant driver” of these longer pollen seasons and is a major reason for increasing concentrations of pollen. See the research at Anthropogenic climate change is worsening North American pollen seasons, PNAS.

Compared to 30 years ago, the pollen season is starting 20 days earlier and lasting for almost a month longer. This is mainly because of increasing temperatures from climate change.

Health Impacts of More Pollen and Longer Seasons

Birch trees are a primary source of pollen. These trees can be found across the state and are the third most abundant pollen type found in Seattle. Scientists predict there will be eight times as much birch pollen in our region by the end of the century. Learn more about this research at Pollen calendars and maps of allergenic pollen in North America, Aerobiologia

According to these predictions, pollen season would start two to four weeks earlier than it does now. In addition, climate change could increase the range of plants and their pollen. And with longer, stronger pollen seasons come major health consequences:

  • People with allergies may struggle with more reactions over a longer pollen season.
  • More people could be diagnosed with asthma.
  • Viral infections could become more frequent.
  • School performance and workplace productivity could decrease.
  • More people will likely visit emergency rooms with respiratory problems.

How to Reduce the Effects of Pollen

At the Department of Health, we want you to be as healthy as possible. If you’re among millions of people in the U.S. who have pollen allergies, consider these steps to protect yourself.

People who experience seasonal allergies can often use over-the-counter medication to get through itchy and sneezy days. But sometimes, people who suffer from asthma and other respiratory illnesses have dangerous, life-threatening reactions. See your medical provider if you have trouble breathing.

Help Study Pollen

By keeping track of pollen levels, we can help researchers, health care workers, and those with respiratory issues.

Surveillance Efforts 

In 2024, we intend to implement a pollen surveillance system that will consist of 11 monitors with at least one in each climate zone in Washington state. The pollen surveillance system is intended to help people who suffer from seasonal allergies by providing real-time pollen detection information.  

  • Surveillance will be conducted using an APS400 Particulate Sensor by PollenSense providing live pollen data. 
  • The information from the monitors will be publicly available on the monitor manufacturer’s phone app, Pollen Wise, and on a web based DOH dashboard that will become available by the end of 2024.  
  • Information about distinct tree, grass, and weed pollens will be available to allow users to filter for specific pollens they are allergic to. 
  • The web based DOH dashboard will provide pollen data based on location, including statewide and location specific data. 

Take Action to Fight Climate Change 

We offer ways you can help reduce your impact on climate change. For example, you can:

  • Vote.
  • Invest in the future.
  • Speak up.
  • Drive less.
  • Reduce food waste.