Question

Assume the average \(\mathrm{CO}_{2}\) concentration in the atmosphere is 406 ppm (as of January 2017 ). The actual concentration of \(\mathrm{CO}_{2}\) at different sites will vary. Speculate on whether the concentration of \(\mathrm{CO}_{2}\) would be expected to be higher, lower, or the same as this average value in a typical large city.

Short answer

\(\mathrm{CO}_2\) concentrations would likely be higher in a large city than the global average.

Step-by-step solution

Understand the Average Value

The given average \(\mathrm{CO}_2\) concentration in the atmosphere is 406 ppm, which represents the global average recorded in January 2017. This value is calculated based on various measurement sites around the world, including remote and urban locations.

Consider Factors Affecting \\(\mathrm{CO}_2\\) Levels

\(\mathrm{CO}_2\) levels are influenced by multiple factors such as industrial activities, vehicle emissions, and population density, which are typically higher in large cities compared to rural or remote areas.

Analyze Urban Impact on \\(\mathrm{CO}_2\\) Levels

Large cities often have high \(\mathrm{CO}_2\) emissions due to many vehicles, industries, and densely packed living areas, contributing to local increases in \(\mathrm{CO}_2\) levels.

Compare City Levels to Global Average

Considering the significant \(\mathrm{CO}_2\) sources in urban environments, it is reasonable to speculate that \(\mathrm{CO}_2\) concentrations in a typical large city would be higher than the global average of 406 ppm.

Key concepts

Urban Air Quality

Urban air quality is a critical topic, especially in big cities where many people live and work. The quality of air in urban areas is often affected by a variety of factors that can increase levels of pollutants like carbon dioxide (CO2). A typical large city has numerous sources of CO2 emissions, including heavy traffic, dense population areas, and a concentration of industries.
These sources converge to notably contribute to the overall air pollution, and in turn, have a significant impact on public health and the environment. To understand how urban air quality can be so varied, consider:

• High population density leading to increased energy consumption.
• More vehicles contributing to additional exhaust emissions.
• Industrial zones emitting large quantities of pollutants.

Consequently, CO2 levels in cities are generally higher than in rural areas, making it essential to regularly monitor and take actions to improve the urban air quality.

Vehicle Emissions

Vehicle emissions are a major factor influencing \( \mathrm{CO}_2 \) levels in cities. Automobiles, especially those running on gasoline and diesel, burn fossil fuels which release CO2 among other pollutants into the atmosphere.
Here's how vehicles contribute to the increase in \( \mathrm{CO}_2 \) concentrations:

• Combustion engines convert fuel into energy, releasing CO2
• Traffic congestion leads to more idling and higher emissions
• Larger vehicles like trucks emit more CO2 than smaller cars

Efforts to reduce vehicle emissions are essential to decrease urban CO2 levels. Transitioning to electric vehicles, improving public transit, and promoting carpooling are some of the measures that can be adopted to lower these emissions.
Addressing vehicle emissions not only helps to reduce CO2 levels but also improves urban air quality overall.

Industrial Activities

Industrial activities are among the most significant contributors to atmospheric \( \mathrm{CO}_2 \) levels in urban areas. Factories and industrial plants require considerable energy to operate, often relying on burning fossil fuels, which release CO2.
Here are key reasons why industries elevate local CO2 concentrations:

• Fossil fuel combustion for energy and heat generation
• Chemical processes in manufacturing that produce CO2 as a byproduct
• High concentration of industrial facilities in urban areas, amplifying local emissions

Reducing industrial emissions is pivotal to managing urban CO2 levels. This can involve changing to cleaner energy sources, enhancing energy efficiency, and investing in carbon capture technologies.
Such measures can significantly mitigate the harmful environmental impacts of industrial CO2 emissions, making cities healthier places to live and work.

Global Average CO2 Levels

Global average \( \mathrm{CO}_2 \) levels provide a benchmark for understanding how CO2 concentrations can vary across the planet. This average is calculated by measuring atmosphere CO2 at various sites worldwide, including both remote and urban locations.
The number "406 ppm" reflects the average concentration recorded in January 2017, illustrating the pervasive nature of CO2 emissions. Factors contributing to global CO2 levels include:

• Natural processes such as respiration and decay releasing CO2
• Human activities like deforestation and burning fossil fuels
• Global air currents that disperse CO2 evenly in the atmosphere

Comparing the measured CO2 levels in specific locations, like large cities, against the global average helps in understanding the impact of localized emissions. Cities usually exhibit higher CO2 concentrations due to localized sources of emissions, as discussed previously, emphasizing the need for targeted emission reduction strategies to combat further increase in average global CO2 levels.
This highlights the importance of collective global efforts to curb CO2 emissions.