Pollution's Impact: Cities Choking Under The Smog

Cities are hotspots for poor air quality, with 90% of global citizens living in areas that exceed the safe level of air quality as defined by the World Health Organisation (WHO). Urban areas produce roughly 78% of carbon emissions and airborne pollutants that adversely affect over 50% of the world's population living in them. The dense concentration of vehicles, industrial facilities, and construction projects are huge sources of emissions. Air pollution is linked to a range of health issues, including heart failure, strokes, poor cognition, and lung cancer in older people, with children being particularly vulnerable to the effects of air pollution.

Air pollution is a serious health threat, causing strokes, heart disease, lung cancer, asthma, and more

In addition, air pollution exacerbates respiratory conditions such as asthma, COPD, and bronchitis. Research has found that children exposed to high levels of air pollutants are more likely to develop bronchitis symptoms in adulthood and are at an increased risk of developing asthma. Furthermore, air pollution is linked to adverse pregnancy outcomes, including preterm birth, low birth weight, and maternal and fetal illness and death.

The impact of air pollution extends beyond health, with economic consequences for cities. The costs of dealing with the effects of pollution on basic services, infrastructure, housing, and human livelihoods can be significant. However, some cities have successfully improved their air quality through interventions. For example, Beijing, China, reduced its PM2.5 levels by 36% in five years by implementing controls on power plant and industrial emissions, as well as introducing new fuel quality and vehicle emission standards.

As urban areas are major sources of greenhouse gas emissions, contributing to approximately 70% of global CO2 emissions, addressing local pollution is crucial. By cutting emissions, cities can improve the health of their residents and play a vital role in mitigating climate change. This involves adopting renewable energy sources, cleaner production techniques, and regulations or incentives to limit industrial and transportation emissions. While air pollution poses a severe threat, coordinated efforts at the global, regional, national, and local levels can lead to successful mitigation and improved urban air quality.

Urban activities are major sources of greenhouse gas emissions, with transport being a significant contributor

Cities are at the forefront of both the impacts of air pollution and the progress and interventions that can be made to tackle the issue. Urban activities are major sources of greenhouse gas emissions, with transport being a significant contributor.

The transportation sector is one of the largest contributors to anthropogenic U.S. greenhouse gas emissions. In 2022, the sector accounted for the largest portion (28%) of total U.S. GHG emissions. This includes emissions from cars, trucks, commercial aircraft, and railroads, among other sources. Transportation emissions do not include emissions from non-transportation mobile sources such as agriculture and construction equipment. The dense concentration of vehicles in cities is a huge source of emissions. Vehicles, particularly those fuelled by diesel, are a significant source of air pollution and greenhouse gas emissions. Transportation accounts for about half of the emissions in cities.

The high energy demands of cities also contribute to the combustion of fossil fuels, releasing pollutants into the atmosphere. Other key sources include burning waste and solid fuels like coal and wood in homes. Some cities' poor air quality levels are exacerbated by weather conditions. Urban planning has often focused on the movement of cars rather than people, and congestion problems have been made worse by the growth in home deliveries.

Initiatives such as the Clean Air Fund's Breathe Cities partnership aim to support cities in cutting air pollution and climate emissions. The initiative, which began in London, brings together data, communities, and city decision-makers to improve urban air quality. The creation and expansion of Clean Air Zones in several UK cities have the potential to save millions of lives.

Improving mobility and public transport is key to clearing the air and creating sustainable cities. Air pollution is a serious threat to public health, and improving air quality can help protect vulnerable populations, including children, older adults, and people with lung diseases such as asthma and COPD.

The dense concentration of vehicles, industrial facilities, and construction projects are huge sources of emissions

The dense concentration of vehicles, industrial facilities, and construction projects are significant sources of emissions that affect cities and their residents.

Vehicles are a major contributor to city pollution, particularly in densely populated urban areas. Transportation is the largest source of planet-warming greenhouse gas emissions in the United States, with the majority of these emissions originating from driving in cities and suburbs. Per capita emissions have increased in most metropolitan areas, and residents in transit-friendly cities like New York contribute less CO2 from driving compared to less dense cities like Dallas. To address this, cities like New York and California have implemented strategies such as providing tax incentives for electric and hybrid vehicles and building more charging stations.

Industrial facilities, particularly large-scale plants, also play a significant role in city pollution. In Europe, the costs of air pollution caused by the largest industrial plants averaged between €268 billion and €428 billion per year, equivalent to about 2% of the EU's GDP in 2021. Coal power plants and thermal power stations are among the most polluting facilities, causing significant damage to the environment, climate, and people's health. The EU energy sector has made strides in reducing pollution, accounting for about 80% of the total decrease in industrial pollution costs between 2012 and 2021.

Construction projects contribute significantly to pollution in cities, especially in large-scale developments. Machinery and vehicles used in construction often run on diesel fuel, releasing pollutants such as carbon monoxide, carbon dioxide, nitrogen oxides, and hydrocarbons. The extended use of diesel-powered equipment during construction exacerbates climate change by releasing greenhouse gas emissions. Additionally, construction activities impact air quality, accounting for a substantial portion of particulate matter (PM10) and fine particulate matter (PM2.5) emissions, as well as contributing to nitrous oxide emissions.

The impacts of these emission sources are wide-ranging, affecting not only the environment but also the health and well-being of city residents. To mitigate these effects, cities are implementing various strategies, including regulating industrial pollution, promoting electric vehicles, and encouraging behavioural changes to reduce vehicle emissions. Additionally, construction projects can adopt more sustainable practices, utilize pollutant-free building materials, and implement emission reduction targets to minimize their environmental impact.

Local policies have improved air quality in some cities, while pollution has worsened in others

Cities are major contributors to climate change, with urban activities being a significant source of greenhouse gas emissions. Urban areas are responsible for 70% of global CO2 emissions, with transport and buildings being the largest contributors.

Local policies have proven to be effective in improving air quality in some cities. For instance, Beijing, China, reduced its PM2.5 levels by 36% in five years by implementing controls on power plant and industrial emissions, as well as introducing new fuel quality and vehicle emission standards. Other cities in high-income regions and East Asia have also seen a decline in NO2 exposures. Globally, 211 more cities met the WHO guideline of 10 µg/m3 for NO2 in 2019 compared to 2010.

At the local level, zoning policies can directly impact the air quality and health of citizens. Local governments can improve air quality by holding industries such as agriculture, transportation, construction, and manufacturing accountable for environmental laws and codes. Additionally, providing education, guidance, and incentives for reducing air pollution can be effective. This includes encouraging the use of electric vehicles, carpooling, and public transportation, as well as promoting energy efficiency and the use of renewable energy sources.

However, pollution has worsened in some regions. PM2.5 levels tend to be highest in low- and middle-income countries, while NO2 levels are high across countries of all income levels. Climate change impacts cities through rising global temperatures, increased extreme weather events, and the spread of tropical diseases, all of which affect basic services, infrastructure, and the health of city dwellers.

Air pollution disproportionately affects people of colour and people with lower incomes

Urban areas are major contributors to climate change, with cities responsible for 70% of global CO2 emissions. While cities are taking action to reduce emissions and combat climate change, air pollution continues to disproportionately affect people of colour and people with lower incomes.

People of colour are more likely to live in areas with higher levels of pollution. A 2011 analysis found that non-Hispanic Black and Hispanic people were more likely to live in counties with worse particle and ozone pollution. A 2008 study of Washington, DC, found that areas with higher Medicaid enrollment, which tended to have predominantly African American populations, had poorer air quality and higher rates of asthma. Similarly, a 2016 study of New Jersey residents showed that communities with larger African American populations, lower home values, and lower median incomes faced a higher risk of premature death from long-term exposure to particle pollution.

Socioeconomic status also plays a significant role in the impact of air pollution. Multiple studies have found that lower-income groups are exposed to higher levels of air pollution, particularly fine particle pollution (PM2.5). From 2004 to 2016, lower-income areas in the US were exposed to higher average PM2.5 levels, and disparities in exposure relative to safety standards have been increasing over time among racial and ethnic minority groups.

The reasons for these disparities are complex. Historical housing policies and systemic racism have contributed to the concentration of people of colour in areas with higher pollution levels. Additionally, people of colour are more likely to live near major sources of pollution, such as industrial areas and busy roads, which further increases their exposure to harmful pollutants.

Addressing these disparities requires targeted interventions and regulations. Reducing emissions from industry and transport can improve urban air quality, and cities can play a crucial role in implementing cleaner production techniques and incentivizing the use of renewable energy sources. By taking coordinated action at the global, regional, national, and local levels, it is possible to mitigate the effects of air pollution and ensure that all communities have access to clean air, regardless of race or income.

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