post-lockdown auto emissions can't hide in the grass
Graduate student Cindy Yañez taking inventory of plant samples mailed in by community scientists for radiocarbon dating. Credit: C. Czimczik/UCI

University of California scientists have a new way to demonstrate which neighborhoods returned to pre-pandemic levels of air pollution after COVID restrictions ended.

Vehicle emissions are the biggest source of carbon dioxide in Southern California’s air. As people drove their cars far less in 2020 compared to 2019 due to the pandemic, there was a major drop in CO2 on regional highways. A new study published in AGU Advances using a mobile laboratory shows the CO2 drop was roughly 60%.

By analyzing grass samples from across the state, the same study also showed in fine detail that some parts of California were back to high levels of emissions by 2021, while others—generally in more affluent areas—were not.

“Community scientists sent us hundreds of wild grass samples. We analyzed them for radiocarbon content, which is a proxy for fossil fuel emissions,” said Francesca Hopkins, UC Riverside assistant professor of climate change and study co-author.

“Plants absorb CO2 during photosynthesis and incorporate it into their tissues, recording a snapshot of local fossil fuel inputs in the process,” said study lead Cindy Yañez, formerly of UCR, now an Earth System Sciences doctoral student at UC Irvine.

post-lockdown auto emissions can't hide in the grass
Sample of the wild grass used in the study of vehicle emissions. Credit: Francesca Hopkins/UCR

The team’s grass samples revealed that coastal Orange County retained their pandemic-related reduction in emissions, and that San Francisco has fared better than Los Angeles. Both the Los Angeles metro area and Pasadena had bigger pollution rebounds than the coast, or than the state as a whole.

“We believe many of the differences we saw can be attributed to how many people are able to continue working remotely,” Hopkins said. “Other likely factors include the number of low-emission or electric vehicles in an area, and distance from industrial warehouses, with heavy big-rig traffic.”

Drilling down further, the study detailed emissions levels on specific roadways in San Francisco. Since the city’s Great Highway remained closed to cars until the end of 2021, it retained its low emissions levels into 2021. However, the city’s 19th Avenue, where traffic was redirected, showed a big increase in fossil fuel CO2 based on radiocarbon content in the grass.

The researchers have found that using wild grasses offers several advantages over other techniques.

post-lockdown auto emissions can't hide in the grass
Mobile laboratory used to collect freeway air samples for the emissions study. Credit: Francesca Hopkins/UCR

“People traditionally measure radiocarbon in the air by collecting large, 2-liter flasks of air, which you then have to take to a lab and extract. It’s time consuming,” Hopkins said. “Grass already got the CO2 out of the air and did a lot of the work for us. It’s less expensive and lets us measure in new locations that weren’t previously possible.”

In addition, existing satellite or urban tower networks can measure CO2 in more economically developed cities. However, these measurement systems cannot offer neighborhood-scale observations needed to inform policies that are intended to reduce greenhouse gas emissions and ultimately, climate change.

For example, cities could decide to reduce their carbon footprint by restricting vehicle traffic on a particular road or closing down another known source of emissions. Then they could use measurements of the grass in that area to measure the success of that action.

“As the world gets more serious about mitigating climate-warming CO2, we need metrics to let us know if we’re doing a good job of reducing it,” Hopkins said. “We also want to make sure communities most affected by emissions are getting the air quality benefits of reducing CO2.”

More information: C. C. Yañez et al, Reductions in California’s Urban Fossil Fuel CO 2 Emissions During the COVID‐19 Pandemic, AGU Advances (2022). DOI: 10.1029/2022AV000732

Journal information: AGU Advances

Provided by University of California – Riverside

Citation: Post-lockdown auto emissions can’t hide in the grass (2022, December 5) retrieved 5 December 2022 from https://phys.org/news/2022-12-post-lockdown-auto-emissions-grass.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

TECH NEWS RELATED

TikTok EU ban on the table if social network doesn’t comply with new laws

TikTok is one of the most popular social networks out there. But TikTok is also a cause of concern for western governments that worry about the company’s ties to the Chinese government. TikTok can’t run on most devices the US government issues, and there has been talk of a ...

View more: TikTok EU ban on the table if social network doesn’t comply with new laws

Don’t Buy a Foldable Until Samsung Brings This Prototype to Life

Samsung Display via The Verge The world of foldable phones is surprisingly stagnant. The Galaxy Z Fold gets a tiny little upgrade every year, and rival phone brands loosely copy Samsung’s homework. But a new Samsung Display prototype called the “Flex In & Out” could turn this narrative on ...

View more: Don’t Buy a Foldable Until Samsung Brings This Prototype to Life

Best free sports streaming apps in 2023

Cutting the cord on cable television is something tons of people have done over the past five years. But that hasn’t proven to be the smartest way to continue to watch sports. Whether it comes from premium sports website subscriptions to keep tabs on your favorite players, or even fantasy ...

View more: Best free sports streaming apps in 2023

Avengers 5 might have Ant-Man in it, Quantumania star teases

The first MCU Phase 5 movie will be Ant-Man and the Wasp: Quantumania, the third installment in the Ant-Man franchise and a film with much higher stakes than the previous episodes. The sequel will deliver the MCU’s first Kang (Jonathan Majors) villain after we met a somewhat good He Who ...

View more: Avengers 5 might have Ant-Man in it, Quantumania star teases

Sharing a Netflix Account? Get Ready to Pay For It

DANIEL CONSTANTE/Shutterstock.com Netflix is about to get serious in its efforts to eliminate freeloaders. If you share a Netflix account with family or friends outside your household, get ready to pay for it. A new “paid sharing” system could roll out starting next month, and you’ll have to pay a ...

View more: Sharing a Netflix Account? Get Ready to Pay For It

‘7 Wonders’ Board Game Gets a New ‘Edifice’ Expansion

Asmodee and Repos Production Board game lovers have a wonderful reason to celebrate today. Board game makers Asmodee and Repos Production announced their latest collaboration: 7 Wonders Edifice, an expansion to the popular board game 7 Wonders. The game launches on February 24th for $29.99. 7 Wonders: Edifice adds ...

View more: ‘7 Wonders’ Board Game Gets a New ‘Edifice’ Expansion

T-Mobile Kicks Off 2023 With Another Data Breach

r.classen / Shutterstock.com In a press release, T-Mobile confirms that it detected a data breach in its systems on January 5th. A “bad actor” managed to steal personal information (but not financial data) from around 37 million customers. This is the eighth T-Mobile data breach since 2018. The hacker ...

View more: T-Mobile Kicks Off 2023 With Another Data Breach

Apple appeals to UK competition watchdog investigation about mobile browser dominance

Apple has filed an appeal against the UK’s competition watchdog regarding its dominance of mobile browsers in the cloud gaming market, reports Reuters. The Competition and Markets Authority started investigating this dominance by the Cupertino firm and Google. Lawyers representing Apple believe the investigation should be reviewed as CMA ...

View more: Apple appeals to UK competition watchdog investigation about mobile browser dominance

Galaxy S23 Ultra release date and specs leak finally reveals everything about the new model

WhatsApp for iOS rolling out the ability to create a chat with yourself

Amazon Prime Music Unlimited changes streaming prices, now matches Apple Music

Deadpool 3 and Secret Wars to feature Fox’s X-Men, according to Marvel insider

Report: OLED iPad Pro still on track for 2024 release, 2026 for MacBook Pro

How to negotiate over practically anything

HomePod 2 praised in exclusive hands-on before launch

M2 Pro MacBook Pro Amazon preorder deal gives you $50 off

What “choice” means for millions of women post-Roe

Singapore FinTech firm Pilon secures $5.2M seed funding led by Wavemaker Partners

Capital Square Partners and Basil Technology team up for $700M tech fund in Asia

This feel-good movie about man’s best friend is dominating Netflix

OTHER TECH NEWS

Top Car News Car News