The Top 10 States With the Highest Total Carbon Dioxide Emissions

The United States has the second-highest carbon dioxide emissions in the world, behind only China. In 2021, the United States emitted 5,586 million metric tons of carbon dioxide into the atmosphere. That’s more than double the emissions of the entire European Union. However, some U.S. states contribute far more to its high carbon dioxide emissions than others. This article explores the 10 states with the highest carbon dioxide emissions in 2021. Collectively, these 10 states generate over half of the entire country’s emissions! The data for each state’s overall carbon dioxide emissions and carbon dioxide emissions per capita is from the United States Energy Information Administration.

It is not a coincidence that many of the states on this list are also some of the largest states in the U.S. by population. A higher population generally means higher emissions, and this is especially true in wealthier nations. According to the Intergovernmental Panel on Climate Change’s 2022 report, population growth and gross domestic product (GDP) per capita are the largest drivers of carbon dioxide emissions. Due to this association, many of the states on this list are the most populous U.S. states and are home to some of the largest cities in the U.S. However, two of the states on this list are interesting exceptions to that trend. Let’s explore the top 10 states with the highest carbon dioxide emissions.

1. Texas

Everything is bigger in Texas, as the old saying goes. As it turns out, this even applies to carbon dioxide emissions. Texas has had the highest carbon dioxide emissions of any state since at least 1970. In 2021, Texas emitted 663.5 million metric tons of carbon dioxide into the atmosphere. That’s more than double California, which has the second-highest carbon dioxide emissions. Texas had a population of 29,558,864 in 2021, placing its carbon dioxide emissions per capita at 22.4 metric tons. If Texas was an independent nation, it would have the eighth-highest carbon emissions of any country in the world.

So, why does Texas have such high carbon dioxide emissions? One reason is that Texas, like most of the states on this list, has a high population. In fact, Texas is the second-most populous state in the U.S. after California. However, the high population does not account for all of the emissions in Texas. If population was the only factor, then California would have the highest emissions. The other reason that Texas emits so much carbon dioxide is its massive fossil fuel industry. In fact, according to the United States Energy Information Administration, Texas is responsible for 42% of crude oil production and 27% of natural gas production in the U.S. This makes Texas the largest crude oil and natural gas producing state.

After industry, transportation is the second-highest contributor to carbon dioxide emissions in Texas. In fact, Texas drivers account for a whopping 0.48% of the entire world’s carbon emissions, which is more than every train in the world.

2. California

California emitted 324 million metric tons of carbon dioxide into the atmosphere in 2021. Its population in 2021 was 39,142,991, placing its carbon dioxide emissions per capita at 8.3 metric tons. California’s high carbon dioxide emissions are largely due to its massive population. It is the most populous U.S. state and is home to four of the 20 most populous cities in the U.S. Additionally, California has a massive economy, which is another major factor for carbon dioxide emissions. Transportation is the largest contributor to California’s carbon dioxide emissions. It generates 40% of California’s emissions, with passenger vehicles alone generating 28%.

3. Florida

Florida has the third-highest carbon dioxide emissions in the U.S., emitting 226.3 million metric tons of carbon dioxide into the atmosphere in 2021. It is also the third-most populous state in the U.S. Florida’s high carbon dioxide emissions are largely due to its high population. In 2021, Florida had a population of 21,828,069, placing its carbon dioxide emissions per capita at 10.4 metric tons. Transportation and energy create the vast majority of Florida’s emissions, with transportation at 42.2% and energy at 40.3%.

4. Pennsylvania

Pennsylvania ranks number four for carbon dioxide emissions in the U.S. In 2021, Pennsylvania emitted 213.5 million metric tons of carbon dioxide into the atmosphere. That means that Pennsylvania alone is responsible for 1% of the entire world’s emissions. Pennsylvania is the fifth-most populous state in the U.S., with a population of 13,012,059 in 2021. Its carbon dioxide emissions per capita is 16.4 metric tons.

Like Texas, industry is the number one contributor to Pennsylvania’s emissions. In fact, just 12 of the state’s industrial facilities are responsible for one-fifth of the entire state’s emissions.

5. Ohio

In 2021, Ohio emitted 194 million metric tons of carbon dioxide into the atmosphere. Its population in 2021 was 11,764,342, placing its carbon dioxide emissions per capita at 16.5 metric tons. Ohio’s high emissions are largely due to its high population. The largest contributing factors to Ohio’s emissions are electricity/heat and transportation.

6. Louisiana

With a relatively small population, Louisiana is one of the two outliers on this list. Louisiana’s population in 2021 was 4,627,098, making it the 25th-most populous state. Nevertheless, in 2021 Louisiana emitted 188.6 million metric tons of carbon dioxide into the atmosphere. Due to its high emissions and relatively low population, Louisiana ranks fifth in the U.S. for carbon dioxide emissions per capita with a whopping 40.8 metric tons.

Like Texas and Pennsylvania, the largest contributor to carbon dioxide emissions in Louisiana is industry. Over half of the state’s emissions come from Louisiana’s chemical corridor, a small 85-mile-long region also known as Cancer Alley. This region, which stretches between New Orleans and Baton Rouge, has hundreds of chemical plants and refineries.

7. Illinois

In 2021, Illinois emitted 184.2 million metric tons of carbon dioxide into the atmosphere. Its population was 12,686,469 in 2021, placing its carbon dioxide emissions per capita at 14.5 metric tons. Illinois’ high carbon dioxide emissions are largely due to its high population. The largest contributing factors to Illinois’ emissions are transportation and electricity/heat.

8. Indiana

Indiana is the other outlier on this list, along with Louisiana. Its population was 6,813,532 in 2021, making it the 17th-most populous state. In 2021, Indiana emitted 166.4 million metric tons of carbon dioxide into the atmosphere. Its carbon dioxide emissions per capita is 24.4 metric tons. The largest contributors to Indiana’s emissions are electricity/heat and industry. Indiana’s high electricity emissions are due to the fact that nearly three-quarters of its electricity comes from coal.

9. New York

In 2021, New York emitted 154 million metric tons of carbon dioxide into the atmosphere. Although New York has the eighth-highest carbon dioxide emissions overall, it also has the lowest emissions per capita of any state. New York’s population was in 2021, placing its carbon dioxide emissions per capita at 7.9 metric tons. One reason New York has high emissions overall but low emissions per capita is New York City. In New York City, walking and public transportation are common methods of transportation, while cars are a less common method compared to other major American cities.

10. Michigan

In 2021, Michigan emitted 147.8 million metric tons of carbon dioxide into the atmosphere. Its population was 10,037,504 in 2021, placing its carbon dioxide emissions per capita at 14.7 metric tons. Michigan’s high carbon dioxide emissions are largely due to its high population. The largest contributing factors to Michigan’s emissions are electricity/heat and transportation.

Summary of the States With the Highest Carbon Dioxide Emissions

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