America's Pollution Footprint: Global Impact And Responsibility

The United States is the second-largest carbon dioxide polluter globally, after China, and is responsible for 13.5% of global carbon dioxide emissions. The US has a long history of burning coal, oil, and natural gas, and despite having just over 4% of the world's population, it is responsible for almost a third of the excess carbon dioxide in the atmosphere. The country's power plants are the single largest source of carbon dioxide emissions, with coal-fired plants being the biggest culprit, emitting 80% of carbon dioxide pollution from US power plants in 2007. While the US has committed to reducing its emissions, it has also faced criticism for its dependence on outdated technology and fossil fuels, which contribute significantly to global warming and environmental degradation.

America's per capita emissions

In 2020, the United States was the second-highest emitter of carbon dioxide, with 13.5% of global emissions. However, when considering per capita emissions, the United States has consistently been one of the top emitters. The typical American burns roughly twice as much carbon dioxide as the average person in Europe or Japan and ten times as much as the average person in India. This is due to the country's long history of burning coal, oil, and natural gas, which has resulted in the United States being responsible for almost a third of the excess carbon dioxide in the atmosphere.

While the United States has made some progress in reducing emissions, with a 3% decrease in greenhouse gas emissions from 1990 to 2022, other countries have achieved a decoupling of economic growth from CO2 emissions. For example, China has surpassed the United States in total emissions, but when adjusted for population, Americans emit more than twice as much as the average Chinese citizen. This highlights the importance of considering per capita emissions when assessing a country's contribution to global pollution.

To further illustrate the impact of per capita emissions, it is worth noting that the United States is also a major exporter of emissions embedded in traded goods. This means that a portion of the carbon dioxide produced in Asia and Africa is for the production of goods consumed in the United States. As a result, the United States' contribution to global pollution is even higher when considering the consumption-based emissions that occur outside of its geographical boundaries.

In conclusion, America's per capita emissions are significant due to the country's high consumption and lifestyle choices, historical dependence on fossil fuels, and the embedded emissions in traded goods. These factors contribute to the United States' position as one of the top emitters of greenhouse gases per person and reinforce the need for comprehensive action to address its impact on global pollution.

Fossil fuel dependence

Fossil fuels have made up at least 80% of the US fuel mix since 1900. The three primary fossil fuel sources—petroleum, natural gas, and coal—have dominated the country's energy consumption for over a century. While coal was the primary energy source in the late 19th century, it was overtaken by petroleum products in the mid-20th century, with natural gas usage also experiencing a rapid increase during this period.

The United States' dependence on fossil fuels has resulted in significant environmental consequences, particularly regarding carbon dioxide emissions. With just over 4% of the world's population, the US is responsible for a substantial portion of the excess carbon dioxide contributing to global warming. In 2020, the US was the second-highest emitter of carbon dioxide, accounting for 13.5% of global emissions, surpassed only by China at 30.6%.

Historically, the US has been the largest carbon polluter, and its cumulative emissions have had a lasting impact. Carbon dioxide can remain in the atmosphere for up to 200 years or longer, contributing to the heat-trapping gases that drive climate change. The US has faced criticism for its withdrawal from the Paris Climate Deal, which aimed to address these pressing environmental concerns.

To reduce their dependence on fossil fuels, the US has explored alternative energy sources. In 2011, President Barack Obama introduced the Blueprint for a Secure Energy Future, aiming to reduce oil dependence by a third through increased domestic production and the adoption of cleaner alternative fuels. Additionally, there has been a push for renewable energy, public transportation, and "smart growth" development patterns that reduce driving miles and cut gasoline use.

Despite these efforts, the US still faces challenges in transitioning away from fossil fuels. Oil imports have contributed significantly to the country's trade deficit, impacting the economy and increasing dependence on foreign sources. The US has limited domestic oil reserves, and production has declined since its peak in 1970, leading to a heavy reliance on imports from countries like Saudi Arabia and Canada. This dependence on foreign oil has also raised national security concerns, as oil money can fund governments and projects that oppose US interests.

Coal as the biggest culprit

The United States has been burning coal, oil, and natural gas for far longer than other countries. With just over 4% of the world's population, the country is responsible for almost a third of the excess carbon dioxide that is heating the planet. Power plants are the single largest source of US carbon dioxide (CO2) emissions, and coal is the biggest culprit. In 2022, CO2 emissions from burning coal for energy accounted for about 19% of total US energy-related CO2 emissions and about 55% of total CO2 emissions from the electric power sector.

The primary use of coal in the US is for electricity generation, and the main environmental law affecting coal combustion for electricity generation is the Clean Air Act of 1970, signed into law by Richard Nixon. The law imposed significant restrictions on sulfur emissions from new coal-fired power plants. However, in the 1970s, natural gas was scarce and oil was expensive, so there was a boom in building coal-fired power plants despite the Clean Air Act.

The US has also been criticized for its coal extraction methods. Mountaintop removal and valley-fill mining have affected large areas of the Appalachian Mountains in West Virginia and Kentucky. This type of coal extraction involves removing the tops of mountains with explosives, changing the landscape and potentially harming aquatic wildlife downstream.

In recent years, there has been a decline in the US coal industry due to various factors such as the development of more competitive energy sources like natural gas, solar, and wind power, as well as environmental regulations and financial market perceptions of coal as a risky investment. Despite this, coal continues to play a significant role in US energy production, contributing to global warming and climate change.

Greenhouse gas emissions

In 2022, the total US emissions were 6,343.2 million metric tons of CO2 equivalent. The primary sources of US greenhouse gas emissions are the transportation, electricity production, industry, commercial, and residential sectors. Greenhouse gas emissions from transportation come from burning fossil fuels for cars, trucks, ships, trains, and planes. Over 94% of the fuel used for transportation is petroleum-based, including gasoline and diesel. The transportation sector is the largest source of direct greenhouse gas emissions and the second-largest source when indirect emissions from electricity use are included.

Electricity production is the second-largest source of direct emissions, and industrial emissions are the third-largest source. If indirect emissions from electricity use are included, the industrial sector accounts for a much larger share of US greenhouse gas emissions. Commercial and residential emissions come from burning fossil fuels for heat, using gases for refrigeration and cooling in buildings, and waste handling.

Buildings accounted for 6% of 2019 global greenhouse gas emissions, but this figure increases to 16% when electricity use in buildings is included. Fluorinated gases (F-gases) are another source of US greenhouse gas emissions. They are emitted through industrial processes, refrigeration, and the use of various consumer products. Ozone-depleting substances such as chlorofluorocarbons (CFCs) and hydrofluorocarbons (HFCs) are also potent greenhouse gases that the US government is working to reduce.

Historic emissions

The United States has historically emitted more carbon dioxide than any other country. Between 1751 and 2017, the US emitted around 400 billion tonnes of CO2, making it responsible for 25% of historical emissions—twice that of China, the world's second-largest contributor. The US is also responsible for almost a third of the excess carbon dioxide that is heating up the planet.

Up until 1950, more than half of historical CO2 emissions were emitted by Europe, with the majority of these emissions coming from the United Kingdom. Until 1882, over half of the world's cumulative emissions originated from the UK alone. However, over the following century, industrialization in the US led to a rapid increase in its contribution.

In recent years, China has surpassed the US as the world's largest emitter of greenhouse gases. In 2020, China accounted for 30.6% of global carbon dioxide emissions, more than twice as much as the US, which contributed 13.5%. However, it is important to consider historical emissions when determining the biggest emitters, as carbon dioxide can remain in the atmosphere for up to 200 years or longer.

In terms of per capita emissions, the US is still the largest emitter, with 19.2% of historic pollution. While countries with larger populations tend to emit more carbon dioxide, per capita emissions provide a different perspective on the data. According to 2019 figures, countries in the Middle East, such as Qatar, the United Arab Emirates, Bahrain, and Kuwait, are among the world's largest per capita CO2 emitters.

While the US has made strides in reducing emissions, such as the phase-out of leaded gasoline and controls on emissions of lead compounds, its role in causing climate change creates a responsibility to help combat it. This includes providing financial assistance to poorer countries that are disproportionately affected by the impacts of climate change.

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