Nav: Home

How severe drought influences ozone pollution

April 10, 2019

From 2011 to 2015, California experienced its worst drought on record, with a parching combination of high temperatures and low precipitation. Drought conditions can have complicated effects on ozone air quality, so to better understand the process, researchers have analyzed data from two ozone-polluted cities before, during and after the California drought. They report their results in ACS' journal Environmental Science & Technology.

Although ozone in the stratosphere protects the earth from ultraviolet radiation, at ground level the molecule is a harmful air pollutant to humans, animals and plants. Ground-level ozone forms when nitrogen oxide compounds, primarily from motor vehicle emissions, react with volatile organic compounds (VOCs) from natural and anthropomorphic sources. Isoprene, a VOC emitted by plants, is a significant contributor to ozone production during summer months in many locations around the world. However, plants also decrease air ozone levels by taking the gas up through pores in their leaves. Because drought conditions affect both of these plant-related processes, Angelique Demetillo, Sally Pusede and colleagues wanted to examine air concentrations of isoprene and ozone -- as well as leaf area index, nitrogen dioxide and meteorology -- before, during and after the California drought.

For their study, the researchers analyzed publicly available data collected from the ground and satellites in Fresno, an ozone-polluted city close to an oak savanna, and Bakersfield, California. They found that isoprene concentrations did not change significantly during the early drought, but they dropped by more than 50 percent during the most severe drought conditions. The effects of drought on isoprene were also dependent on atmospheric temperature. The researchers found that drought altered ozone production such that the process became chemically more sensitive to the decrease in isoprene and other drought-affected VOCs. These factors led to an estimated overall decrease in ozone production of approximately 20 percent during the severe drought. However, this decrease was offset by a comparable reduction in ozone uptake by plants, leading to only a 6 percent reduction in ozone levels overall during the severe drought period. These results suggest that drought influences on ozone pollution are complex and depend on drought severity and duration, the researchers say.
-end-
The authors acknowledge funding from NASA, the NASA Student Airborne Research Program, the National Suborbital Research Center and the NASA Airborne Science Program.

The paper's abstract will be available on April 10 at 8 a.m. Eastern time here: http://pubs.acs.org/doi/abs/10.1021/acs.est.8b04852

The American Chemical Society, the world's largest scientific society, is a not-for-profit organization chartered by the U.S. Congress. ACS is a global leader in providing access to chemistry-related information and research through its multiple databases, peer-reviewed journals and scientific conferences. ACS does not conduct research, but publishes and publicizes peer-reviewed scientific studies. Its main offices are in Washington, D.C., and Columbus, Ohio.

To automatically receive news releases from the American Chemical Society, contact newsroom@acs.org.

Follow us: Twitter | Facebook

American Chemical Society

Related Drought Articles:

What does drought mean for endangered California salmon?
Droughts threatens California's endangered salmon population -- but pools that serve as drought refuges could make the difference between life and death for these vulnerable fish.
With shrinking snowpack, drought predictability melting away
New research from CU Boulder suggests that during the 21st century, our ability to predict drought using snow will literally melt away.
An evapotranspiration deficit drought index to detect drought impacts on ecosystems
The difference between actual and potential evapotranspiration, technically termed a standardized evapotranspiration deficit drought index (SEDI), can more sensitively capture the biological changes of ecosystems in response to the dynamics of drought intensity, compared with indices based on precipitation and temperature.
Sesame yields stable in drought conditions
Research shows adding sesame to cotton-sorghum crop rotations is possible in west Texas
Mapping the effects of drought on vulnerable populations
The greater frequency of droughts, combined with underlying economic, social, and environmental risks means that dry spells have an increasingly destructive impact on vulnerable populations, and particularly on children in the developing world.
Asia's glaciers provide buffer against drought
A new study to assess the contribution that Asia's high mountain glaciers make to relieving water stress in the region is published this week (May 29, 2019) in the journal Nature.
How severe drought influences ozone pollution
From 2011 to 2015, California experienced its worst drought on record, with a parching combination of high temperatures and low precipitation.
A faster, more accurate way to monitor drought
A new drought monitoring method developed at Duke University allows scientists to identify the onset of drought sooner, meaning conservation or remediation measures could be put into place sooner.
How does the Amazon rain forest cope with drought?
The Amazon rain forest isn't necessarily a place that many would associate with a drought, yet prolonged dry spells are projected to become more prevalent and severe because of climate change.
Trees change inside as drought persists
James Cook University scientists in Australia have found that trees change their anatomy in response to prolonged drought.
More Drought News and Drought Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Our Relationship With Water
We need water to live. But with rising seas and so many lacking clean water – water is in crisis and so are we. This hour, TED speakers explore ideas around restoring our relationship with water. Guests on the show include legal scholar Kelsey Leonard, artist LaToya Ruby Frazier, and community organizer Colette Pichon Battle.
Now Playing: Science for the People

#569 Facing Fear
What do you fear? I mean really fear? Well, ok, maybe right now that's tough. We're living in a new age and definition of fear. But what do we do about it? Eva Holland has faced her fears, including trauma and phobia. She lived to tell the tale and write a book: "Nerve: Adventures in the Science of Fear".
Now Playing: Radiolab

Uncounted
First things first: our very own Latif Nasser has an exciting new show on Netflix. He talks to Jad about the hidden forces of the world that connect us all. Then, with an eye on the upcoming election, we take a look back: at two pieces from More Perfect Season 3 about Constitutional amendments that determine who gets to vote. Former Radiolab producer Julia Longoria takes us to Washington, D.C. The capital is at the heart of our democracy, but it's not a state, and it wasn't until the 23rd Amendment that its people got the right to vote for president. But that still left DC without full representation in Congress; D.C. sends a "non-voting delegate" to the House. Julia profiles that delegate, Congresswoman Eleanor Holmes Norton, and her unique approach to fighting for power in a virtually powerless role. Second, Radiolab producer Sarah Qari looks at a current fight to lower the US voting age to 16 that harkens back to the fight for the 26th Amendment in the 1960s. Eighteen-year-olds at the time argued that if they were old enough to be drafted to fight in the War, they were old enough to have a voice in our democracy. But what about today, when even younger Americans are finding themselves at the center of national political debates? Does it mean we should lower the voting age even further? This episode was reported and produced by Julia Longoria and Sarah Qari. Check out Latif Nasser's new Netflix show Connected here. Support Radiolab today at Radiolab.org/donate.