Traffic Pollution In La: A Dire Situation

Los Angeles is known for its smog, which has prompted California to pass some of the most aggressive air quality regulations in the country. Despite these regulations, the city continues to experience poor air quality. During the coronavirus lockdown, traffic was reduced by more than 40% in some cities, but ozone pollution decreased by only 15% or less. This indicates that sources other than passenger cars, such as trucks, ships, trains, and factories, are major contributors to air pollution in Los Angeles.

Los Angeles' poor air quality during lockdown

Despite a significant reduction in traffic during the lockdown, Los Angeles continued to experience poor air quality. While the lockdown presented an opportunity to assess the impact of reduced traffic on air pollution, the results were not as promising as expected.

Los Angeles has historically struggled with air pollution, with its smog in the 1950s and '60s leading California to implement stringent air quality regulations. Even today, Los Angeles' air pollution is among the worst in the United States, particularly for PM2.5 and ozone levels. PM2.5, or airborne particulate matter, is considered highly detrimental to human health, associated with heart disease, respiratory illness, and premature death.

During the lockdown, an NPR analysis of EPA data revealed that ozone levels in Los Angeles and other cities only decreased by 15% or less, despite traffic reductions exceeding 40%. This disparity underscores the significant contribution of other pollution sources, particularly fleets of trucks associated with the region's major ports. The lockdown highlighted that improving air quality requires addressing emissions from sources beyond passenger cars.

The complex interplay of pollutants also played a role in the persistent air quality issues during the lockdown. While nitrogen oxides (NOx) from cars and trucks contribute to ozone formation, they can also, under certain conditions, temporarily break down ozone molecules. Thus, the reduction in NOx emissions during the lockdown may have had a smaller-than-expected impact on ozone levels.

Additionally, the lockdown's impact on air quality was influenced by weather conditions. Sunlight, heat, wind speed and direction, temperature, and pressure conditions all contribute to the formation and dispersion of pollutants. For example, higher temperatures accelerate the reaction that forms ground-level ozone, increasing its levels.

In summary, the lockdown period in Los Angeles revealed the complex nature of air pollution and the need to address a multitude of factors beyond just traffic emissions to achieve meaningful improvements in air quality.

Trucks as a dominant source of pollution

Los Angeles has long been known for its poor air quality, with severe smog in the 1950s and '60s prompting California to implement aggressive air quality regulations. While traffic and air pollution declined during the coronavirus lockdown, the air quality in Los Angeles remained poor, indicating that sources other than passenger cars are responsible for the city's pollution.

The lockdown provided an accidental experiment to observe the impact of reduced traffic on air pollution. Despite a more than 40% reduction in traffic, ozone pollution decreased by only 15% or less in most places. This revealed that passenger cars are a relatively smaller source of pollution, while heavy-duty transportation, such as trucks and buses, has become the largest source of nitrogen oxides, which contribute to ozone formation.

Los Angeles and Long Beach handle over 30% of the nation's shipping container traffic, requiring a vast network of trucks. During the lockdown, truck activity remained high, with only an 8% decrease across California, as they continued to ensure the delivery of goods to stores. The emissions from these trucks, combined with hot and stagnant weather, cause air pollution to reach dangerous levels in the summer, affecting low-income and racial/ethnic minority communities the hardest.

The complex interaction of pollutants means that reducing one type of pollutant can sometimes make another pollutant worse. For example, nitrogen oxides (NOx) produced by cars and trucks contribute to ozone formation, but under certain conditions, they can also break down ozone molecules. Therefore, a reduction in NOx emissions may lead to an increase in ozone levels.

To address the pollution caused by trucks, California has proposed the sale of electric trucks, but manufacturers have resisted due to the underdeveloped market. Supporters argue that the higher upfront costs would be offset by fuel savings and improved air quality, potentially saving thousands of lives. Additionally, California has set its own tailpipe emissions standards for cars, separate from federal regulations, as part of its efforts to reduce greenhouse gas emissions.

Nitrogen oxide emissions

Nitrogen oxides (NOx) are a group of gases that include nitrogen dioxide (NO2) and nitric oxide (NO). They are produced by motor vehicles, trucks, and heavy-duty transportation as a byproduct of fossil fuel combustion. Los Angeles, a city notorious for its poor air quality, has been found to have high levels of nitrogen oxide emissions.

Nitrogen dioxide is a pungent air pollutant that irritates the airways and is associated with pediatric asthma. It is a key ingredient in the formation of smog and fine particulate matter, which can have negative impacts on human health. Los Angeles, with its large population of 4 million people and an additional 6 million in the surrounding county, has a significant problem with traffic congestion and vehicular emissions. This contributes to the high levels of nitrogen oxide emissions in the city.

In 2019, satellite measurements revealed the extent of Los Angeles' air pollution problem. Researchers found that Los Angeles had the third-highest concentration of NOx molecules in its air among the cities studied, with 4 quadrillion molecules per square centimeter. While the city had shown improvements in reducing NOx emissions between 2006 and 2013, the decline slowed and nearly flattened after 2010. This left Los Angeles with NOx levels well above those of other cities, such as Chicago and Detroit.

The unique geography of Los Angeles also contributes to the problem of nitrogen oxide emissions. The city is located in a basin, which makes it harder for airborne chemicals to escape. As a result, the ozone pollution becomes trapped and remains in the lower atmosphere, causing serious health issues for residents.

To address the issue of nitrogen oxide emissions, Los Angeles has implemented several measures. The Clean Air Action Plan of 2006 has helped reduce particulate matter and nitrogen oxide emissions from port operations, which are a significant source of pollution in the city. Additionally, the current mayor, Eric Garcetti, has set forth a sustainability plan that aims to increase the number of zero-emission vehicles in the city. The goal is to reach 25% by 2025 and 100% by 2050.

Shipping container traffic

Los Angeles has long struggled with poor air quality, and the city's ports are a significant contributor to this issue. The Port of Los Angeles, located in San Pedro, is the largest and busiest container port in the United States. Together, the ports of Los Angeles and Long Beach handle over 30% of the nation's shipping container traffic, making them the region's biggest sources of air pollution.

Cargo ship congestion has been a persistent problem, with a sharp increase in emissions caused by container vessels near Los Angeles and Long Beach. In October 2020, supply chain bottlenecks led to a major backup, with up to 73 container vessels waiting to pull into port. These ships burn low-sulfur diesel fuel, which contributes to air pollution, particularly when they are stuck idling and running their auxiliary engines. The congestion also impacts the ground traffic in and around the ports, with long lines of diesel trucks creating congestion and further adding to the pollution.

The pollution from port activities has severe consequences for the health and well-being of nearby communities. The area is home to many Black and Hispanic residents who are disproportionately exposed to industrial pollution and suffer from higher rates of asthma. Life expectancy in West Long Beach, for example, is eight years shorter than in wealthier neighborhoods farther away from the ports, and community advocates attribute this disparity, at least in part, to pollution.

Efforts have been made to address the pollution caused by port operations. The proposed Cargo Volume Cap for Los Angeles and Long Beach aims to implement a port-wide mass emissions cap and individual emissions caps for each container terminal. Additionally, the Pacific Merchant Shipping Association has suggested doubling the Clean Truck Fee to $20 per TEU to reduce emissions from trucks serving the ports. The International Maritime Organization has also adopted policies to curb carbon dioxide emissions and reduce fuel consumption from ocean-crossing vessels.

While these initiatives are a step in the right direction, the transition to cleaner technologies and fuels will require significant investments and a comprehensive approach involving various stakeholders. The complex nature of the problem, influenced by factors beyond the control of port authorities, underscores the need for collaboration and innovative solutions to mitigate the pollution caused by shipping container traffic in Los Angeles.

Air pollution's impact on low-income communities

Los Angeles has some of the worst air pollution in the United States, with the city ranking 82nd out of 1,517 cities in the 2019 World Air Quality Report. The air pollution in Los Angeles is largely caused by traffic, with motor vehicles representing the leading source of city-wide PM2.5 and nitrogen dioxide, which are ozone precursor pollutants.

A UCLA-led study found that disadvantaged communities in Los Angeles face higher levels of toxic air pollution. The study, which was the first in the US to compare air pollution toxicity to people's socioeconomic conditions, found that air from census tracts in the 25% of communities facing the most socioeconomic disadvantage contained a greater amount of pollution and that this pollution was more toxic. The study's senior author, UCLA professor Suzanne Paulson, stated that "people living in these places experience about 65% higher toxicity than people in the most advantaged group".

The study's lead author, Jiaqi Shen, highlighted the compounding effects of environmental and health factors, noting that "disadvantaged areas can face a situation where the environment is worse, and there is also less access to health care and good nutrition, increasing their health risks". The health risks associated with air pollution exposure include an increased risk of cardiovascular, developmental, metabolic, and respiratory diseases and conditions.

While the sources do not provide a specific definition of "low-income communities", it can be inferred that these communities overlap with those facing the most socioeconomic disadvantages. The UCLA-led study's findings support the conclusion that low-income communities in Los Angeles are disproportionately affected by air pollution and its associated health risks.

Furthermore, the COVID-19 lockdown provided an "accidental experiment" to observe the impact of reduced traffic on air pollution. Despite a reduction in traffic of over 40% in some cities, including Los Angeles, ozone levels only decreased by 15% or less. This suggests that other sources of pollution, such as trucks and ports, continue to have a significant impact on air quality.

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