Quantcast
Science
Los Angeles skyline. Prayitno Photography / CC BY 2.0

U.S. Air Pollution Falling More Slowly Than EPA Data Suggests

U.S. air pollution isn't declining as fast as the Environmental Protection Agency (EPA) has claimed, a study published Monday in Proceedings of the National Academy of Sciences revealed.

To track the levels of nitrogen oxides and carbon monoxide, two pollutants that contribute to smog formation, an international research team used satellite pollution measurements backed up by local air quality monitor readings.


They compared this to EPA data, which is based on readings from air monitors and pollution estimates from vehicles and industry, and came to a surprising conclusion.

While nitrogen oxide levels had fallen by a healthy 7 percent annually from 2005 to 2009, from 2011 to 2015 the decline stalled to a mere 1.7 percent per year. This meant a 76 percent slowdown in pollution decline and contrasted with EPA data, which put the slowdown from 2011 to 2015 at only 16 percent.

A graph showing the discrepancy between EPA and satellite nitrogen oxide measurements. Zhe Jiang, redrawn by Simmi Sinha, UCAR

"We were surprised by the discrepancy between the estimates of emissions and the actual measurements of pollutants in the atmosphere," lead author Zhe Jiang said in a National Center for Atmospheric Research (NCAR) and University Corporation for Atmospheric Research (UCAR) press release. "These results show that meeting future air quality standards for ozone pollution will be more challenging than previously thought."

The researchers, who were funded by NASA, the National Oceanic and Atmospheric Administration, the University of Colorado Boulder and the NCAR-sponsoring National Science Foundation, hypothesized that the difference between the satellite data and the EPA measurements of nitrogen oxide were due to three factors.

  1. The decrease in nitrogen oxide released by cars because of the widespread use of catalytic converters
  2. A relative increase in nitrogen oxide released by boilers and off-road vehicles
  3. A slower decrease in emissions from diesel trucks than expected due to the fact that effective catalytic converters for these vehicles are still being perfected.

The researchers found that carbon monoxide levels had also slowed their decline and hypothesized that this was due to the effectiveness of catalytic converters in cars.

NCAR scientist and study co-author Helen Worden told Bloomberg News that the slowdown in air pollution decline was influenced by the fact that, as the 1970 Clean Air Act succeeded in reducing pollution from cars and factories, pollution sources such as boilers and off-road vehicles that had fallen under the radar before were playing a bigger role.

"To some extent, this is a product of our own success," Worden said. "The relative contribution of those sources is now more important because cars and power plants have gotten better."

Unfortunately, the findings come at a time when the EPA is backtracking on its commitment to its former successes. Since December 2017, the EPA has passed four memos weakening controls on industrial air pollution. And in April, EPA head Scott Pruitt announced the agency would adapt less stringent car emissions standards through 2025.

Show Comments ()
Sponsored
PxHere

Do You Know Where Your Meat Comes From?

By Ronnie Cummins

Consumers know if the tomatoes they buy in the supermarket were imported from Mexico. They know if the sweater they purchased was made in Vietnam.

Keep reading... Show less
Food
Pexels

More Than Good Looks: Try These 10 Edible Flowers

By Brian Barth

Eating flowers seems almost heretical. If plants could talk, wouldn't they say, you can look, even sniff, but please don't chow down on my pretty petals? The dainty apple flower, after all, is what gives way to the fruit, and thus the seed, ensuring the cycle of life continues. Do you dare give into the temptation to pluck it for food?

Keep reading... Show less
Food
Indie Ecology / Instagram

Table-to-Farm-to-Table: Startup Grows Food for Restaurants With Kitchen Leftovers

Food, as we know, is a terrible thing to waste. Roughly one third of the food produced in the world for human consumption gets lost or wasted every year. But what if we could use food waste to create more food?

That's the elegantly full-circle idea behind Indie Ecology, a West Sussex food waste farm that collects leftovers from some of London's best restaurants and turns it into compost. The nutrient-rich matter is then used to grow high quality produce for the chefs to cook with. Call it table-to-farm-to-table—and again and again.

Keep reading... Show less
Climate
Pexels

China’s Global Infrastructure Initiative Could Bring Environmental Catastrophe

By Nexus Media, with William F. Laurance

Humans are ravaging tropical forests by hunting, logging and building roads and the threats are mounting by the day.

China is planning a series of massive infrastructure projects across four continents, an initiative that conservation biologist William Laurance described as "environmentally, the riskiest venture ever undertaken."

Keep reading... Show less
Sponsored
Energy
Alaska's Kenai Fjords National Park, which was impacted by the Exxon Valdez oil spill, could be harmed again if expanded offshore drilling plans go through. National Park Service

Trump’s Offshore Drilling Plan Puts 68 National Parks at Risk

Sixty-eight National Parks along the coastal U.S. could be in danger from devastating oil spills if President Donald Trump's plan to open 90 percent of coastal waters to offshore oil drilling goes through, a report released Wednesday by the Natural Resources Defense Council and the National Parks Conservation Association found.

Keep reading... Show less
Climate
E. coli. The World Health Organizations says antibiotic resistance is "one of the biggest threats to global health, food security, and development today." U.S. Centers for Disease Control and Prevention

Climate Change Could Supercharge Threat of Antibiotic Resistance: Study

By Andrea Germano

The World Health Organization and U.S. Centers for Disease Control and Prevention have previously sounded alarms about the growing issue of antibiotic resistance—a problem already linked to overprescribing of antibiotics and industrial farming practices. Now, new research shows a link between warmer temperatures and antibiotic resistance, suggesting it could be a greater threat than previously thought on our ever-warming planet.

Keep reading... Show less
Sponsored
Renewable Energy
Powerwall residential battery with solar panels. Tesla

Tesla's Massive Virtual Power Plant in South Australia Roars Back to Life

Tesla's plans to build the world's largest virtual power plant in South Australia will proceed after all.

The $800 million (US $634 million) project—struck in February by Tesla CEO Elon Musk and former South Australian Premier Jay Weatherill—involves installing solar panels and batteries on 50,000 homes to function as an interconnected power plant.

Keep reading... Show less
Climate
A French lavender farmer is part of the group suing the EU for more ambitious emissions targets, saying climate change threatens his crop. Iamhao / CC BY-SA 3.0

10 Families Bring First Ever 'People’s Climate Case' Against the EU

Ten families from Fiji, Kenya and countries across Europe who are already suffering the effects of climate change filed a case against the EU Wednesday in a bid to force the body to increase its commitments under the Paris agreement, AFP reported.

Keep reading... Show less
Sponsored

mail-copy

The best of EcoWatch, right in your inbox. Sign up for our email newsletter!