Breathing is going to get tougher
Hotter temps = more air pollution from natural sources
Peer-Reviewed PublicationNot all pollution comes from people. When global temperatures increase by 4 degrees Celsius, harmful plant emissions and dust will also increase by as much as 14 percent, according to new UC Riverside research.
The research does not account for a simultaneous increase in human-made sources of air pollution, which has already been predicted by other studies.
“We are not looking at human emissions of air pollution, because we can change what we emit,” said James Gomez, UCR doctoral student and lead author of the study. “We can switch to electric cars. But that may not change air pollution from plants or dust.”
Details of the degradation in future air quality from these natural sources have now been published in the journal Communications Earth & Environment. About two-thirds of the future pollution is predicted to come from plants.
All plants produce chemicals called biogenic volatile organic compounds, or BVOCs. “The smell of a just-mowed lawn, or the sweetness of a ripe strawberry, those are BVOCs. Plants are constantly emitting them,” Gomez said.
On their own, BVOCs are benign. However, once they react with oxygen, they produce organic aerosols. As they’re inhaled, these aerosols can cause infant mortality and childhood asthma, as well as heart disease and lung cancer in adults.
There are two reasons plants increase BVOC production: increases in atmospheric carbon dioxide and increases in temperatures. Both of these factors are projected to continue increasing.
To be clear, growing plants is a net positive for the environment. They reduce the amount of carbon dioxide in the atmosphere, which helps control global warming. BVOCs from small gardens will not harm people.
“Your lawn, for example, won’t produce enough BVOCs to make you sick,” Gomez explained. “It’s the large-scale increase in carbon dioxide that contributes to the biosphere increasing BVOCs, and then organic aerosols.”
The second-largest contributor to future air pollution is likely to be dust from the Saharan desert. “In our models, an increase in winds is projected to loft more dust into the atmosphere,” said Robert Allen, associate professor of Earth and Planetary Sciences at UCR and co-author of the study.
As the climate warms, increased Saharan dust is likely to get blown around the globe, with higher levels of dust in Africa, the eastern U.S., and the Caribbean. Dust over Northern Africa, including the Sahel and the Sahara, is likely to increase due to more intense West African monsoons.
Both organic aerosols and dust, as well as sea salt, black carbon, and sulfate, fall into a category of airborne pollutants known as PM2.5, because they have a diameter of 2.5 micrometers or less. The increase in naturally sourced PM2.5 pollution increased, in this study, in direct proportion to CO2 levels.
“The more we increase CO2, the more PM2.5 we see being put into the atmosphere, and the inverse is also true. The more we reduce, the better the air quality gets,” Gomez said.
For example, if the climate warms only 2 degrees Celsius, the study found only a 7% increase in PM2.5. All of these results only apply to changes found in air quality over land, as the study is focused on human health impacts.
The researchers hope the potential to improve air quality will inspire swift and decisive action to decrease CO2 emissions. Without it, temperatures may increase 4 degrees C by the end of this century, though it’s possible for the increase to happen sooner.
Gomez warns that CO2 emissions will have to decrease sharply to have a positive effect on future air quality.
“The results of this experiment may even be a bit conservative because we did not include climate-dependent changes in wildfire emissions as a factor,” Gomez said. “In the future, make sure you get an air purifier.”
Coughing
JOURNAL
Communications Earth & Environment
ARTICLE TITLE
The projected future degradation in air quality is caused by more abundant natural aerosols in a warmer world
New study to examine link between air
quality, climate change, and birth
outcomes
PSE Healthy Energy and the University of California, Berkeley partner to develop targeted solutions to climate and public health impacts throughout California’s Contra Costa County
Business AnnouncementOAKLAND, CA – On Monday February 27, the U.S. Environmental Protection Agency (EPA) announced that nonprofit research institute PSE Healthy Energy has been awarded $1,350,000 to study local disparities in exposure to air pollution, heat, and humidity throughout Contra Costa County. The Contra Costa Climate, Air Pollution, and Pregnancy Study will be conducted in partnership with the University of California, Berkeley and will analyze birth outcomes and develop targeted solutions to protect the region’s most vulnerable populations.
“We know that climate change is already increasing exposure to air pollution, extreme heat, and humidity and that these events increase health risks, particularly for vulnerable populations,” said Elena Krieger, director of research at PSE Healthy Energy and principal investigator for the study. “Our aim is to better understand how these exposures relate to birth outcomes and to work with communities and policy makers to develop targeted, community-led, and effective interventions.”
The study will leverage PSE Healthy Energy’s Richmond Air Monitoring Network (RAMN) in combination with additional low-cost air monitors in place throughout Contra Costa County, enabling the team to study local variations in exposure across the region. Over the course of three years, the study will assess disparities in exposure to air pollution, heat, and humidity and their relationship with birth outcomes. The researchers will also assess areas and populations facing the greatest increase in risk from climate change impacts, such as increased heat, humidity, and wildfire smoke.
“Low-cost air pollution sensors can help us understand microscale variations in exposure to air pollution, temperature, and humidity. This more granular understanding can help us uncover how local climate impacts may compound socioeconomic risk factors, such as poverty, low educational attainment, and linguistic isolation, and lead to greater exposure and health disparities,” said Ajay Pillarisetti, assistant professor of Environmental Health Sciences at UC Berkeley and the study’s co-principal investigator.
In the final phase of the project, researchers will work with the identified populations and communities to co-develop a suite of interventions to mitigate exposures, ranging from house-level retrofits to community planning measures such as tree planting. The team will use a mix of cost-benefit and distributional analyses, incorporating community-identified priorities and strategies, to identify policy solutions.
The research grant is part of the EPA’s Science to Achieve Results (STAR) program and was part of $21M in research grant funding announced to investigate cumulative health impacts of climate change on underserved communities.
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About PSE Healthy Energy
PSE Healthy Energy is a nonprofit research institute dedicated to supplying evidence-based scientific and technical information on the public health, environmental, and climate dimensions of energy production and use. We are the only interdisciplinary collaboration focused specifically on health and sustainability at the intersection of energy science and policy. Visit us at psehealthyenergy.org and follow us on Twitter @PhySciEng.
METHOD OF RESEARCH
Observational study