How does CO2 contribute to global warming

In this article, we discuss how carbon dioxide has actively contributed towards global warming over the past few years.

How does CO2 contribute to global warming?

Carbon dioxide is the most abundant greenhouse gas present in the atmosphere which also has the longest residence time than the other greenhouse gases.

Given that its concentration in the atmosphere has risen from 280ppm in the pre-industrial era to 420ppm currently, this has caused a severe increase in global warming.

Not only is it linked to global warming, carbon dioxide is also shown to cause acidification and warming of the oceans.

The Greenhouse Effect and Global Warming

The greenhouse effect, which has been known since 1896, is the natural warming of the globe caused by gases in the atmosphere trapping heat from the sun that would otherwise escape into space.

It’s a good thing that the greenhouse effect exists. It maintains a moderate average temperature of 59 degrees Fahrenheit (15 degrees Celsius) on the globe, making life on Earth bearable. 

Without it, the planet would resemble Mars in terms of being frozen and inhospitable. The issue is that mankind’s insatiable need for fossil fuels for energy is artificially amplifying the natural greenhouse effect. 

What’s the end result? A rise in global warming, which is affecting the planet’s climatic systems in a variety of ways.

Natural greenhouse gases contributed to making the Earth’s climate tolerable before humans began using fossil fuels. The planet’s average temperature would be below freezing if they didn’t exist. 

As a result, we know that even extremely low natural quantities of carbon dioxide and other greenhouse gases may have a significant impact on the Earth’s climate.

CO2 levels now are the highest they’ve been in at least 3 million years. Despite the fact that they only make up 0.04 percent of the atmosphere, this equates to billions of tonnes of heat-trapping gas. 

In the year 2019, mankind released 36.44 billion tonnes of CO2 into the atmosphere, where it will remain for hundreds of years. As a result, there are enough CO2 molecules to cover the whole atmosphere in a heat-trapping blanket.

What are the greenhouse gases?

The greenhouse gases in the atmosphere trap heat and warm the earth. Carbon dioxide, methane, nitrous oxide, and water vapour (all of which exist naturally) are the principal greenhouse gases, as are fluorinated gases (which are synthetic).

Greenhouse gases have a variety of chemical characteristics and are eliminated from the atmosphere through a variety of processes throughout time. 

Carbon dioxide is absorbed, for example, by carbon sinks like plants, soil, and the ocean. Only sunshine in the very high atmosphere can eliminate fluorinated gases.

Factors for determining the effect a greenhouse gas has on global warming

The amount of effect each greenhouse gas has on global warming is determined by three fundamental elements:

  • The first is the amount that is present in the atmosphere. Parts per million (ppm), parts per billion (ppb), and parts per trillion (ppt) are used to quantify concentrations.

    1 ppm for a certain gas, for example, signifies that there is one molecule of that gas in every 1 million molecules of air.
  • The second factor is its lifespan, or the amount of time it spends in the atmosphere.
  • The third factor is how well it traps heat. This is known as its global warming potential, or GWP, and it is a measurement of the total energy absorbed by a gas over a certain length of time in comparison to the emissions of one tonne of carbon dioxide.

Why CO2 is the main culprit

According to preliminary estimates, worldwide average atmospheric carbon dioxide in 2020 will be 412.5 parts per million (ppm), a new high notwithstanding the global economic downturn caused by the COVID-19 epidemic.

In fact, the 2.6 ppm increase over 2019 levels was the fifth-highest in NOAA’s 63-year record. Carbon dioxide levels in the atmosphere have increased by 43.5 parts per million (ppm) since 2000, a 12 percent rise.

Carbon dioxide levels are now greater than they have been in at least 800,000 years. In reality, the last time atmospheric CO2 levels were this high was more than 3 million years ago, during the Mid-Pliocene Warm Period.

During this period, the temperatures were 2°–3°C (3.6°–5.4°F) higher than today’s and sea levels were 15–25 metres (50–80 feet) higher. Carbon dioxide levels are growing mostly as a result of people using fossil fuels for energy. 

Coal and oil contain carbon that plants removed from the atmosphere over millions of years via photosynthesis; humans are returning that carbon to the atmosphere in only a few hundred years.

We emit more carbon dioxide into the atmosphere each year than natural processes can remove, resulting in a net worldwide increase in carbon dioxide.

The quicker the yearly growth rate, the more we exceed what natural processes eliminate. Carbon dioxide levels in the atmosphere grew at a pace of about 0.6 ppm per year in the 1960s.

Carbon dioxide is a greenhouse gas, which means it absorbs and reflects heat. Earth’s land and ocean surfaces, which have been warmed by sunlight, constantly emit thermal infrared radiation.

Unlike oxygen or nitrogen, which make up the majority of our atmosphere, greenhouse gases retain heat and slowly release it, much like bricks in a fireplace after the fire has gone out. 

Carbon dioxide is the most significant long-lived greenhouse gas on the planet. It absorbs less heat per molecule than the greenhouse gases methane and nitrous oxide, but it’s more plentiful and lasts far longer in the atmosphere. 

Carbon dioxide increases account for almost two-thirds of the entire energy imbalance that is driving the Earth’s temperature to rise.

Main activities linked to emissions of CO2

As we’ve seen so far, CO2 arises primarily from the combustion of fossil fuels. Some of the main sectors which contribute to CO2 are:

  • Transportation
  • Electricity
  • Industry

We shall discuss these in more detail.


Transportation of persons and products using fossil fuels such as gasoline and diesel was the major source of CO2 emissions in 2019, accounting for around 35 percent of overall CO2 emissions and 28 percent of total greenhouse gas emissions in the United States.

This category comprises highway and passenger cars, air travel, maritime transportation, and rail transportation.


In the United States, electricity is a major form of energy that is used to power homes, businesses, and industries. 

In 2019, fossil fuel combustion for electricity generation was the second largest source of CO2 emissions in the United States, accounting for around 31% of total CO2 emissions and 24% of total greenhouse gas emissions.

CO2 emissions vary depending on the kind of fossil fuel used to produce power. Burning coal produces more CO2 than burning natural gas or oil to create the same amount of power.


Many industrial operations release CO2 as a result of the use of fossil fuels. 

Several activities, including the manufacture of mineral products such as cement, the manufacture of metals such as iron and steel, and the manufacture of chemicals, also emit CO2 through chemical reactions that do not entail combustion. 

In 2019, fossil fuel burning from different industrial processes accounted for around 16% of total CO2 emissions and 13% of total greenhouse gas emissions in the United States.

Many industrial operations consume energy, which results in CO2 emissions from power generation indirectly.


Carbon dioxide is the most abundant greenhouse gas present in the atmosphere which also has the longest residence time than the other greenhouse gases.

Given that its concentration in the atmosphere has risen from 280ppm in the pre-industrial era to 420ppm currently, this has caused a severe increase in global warming.

Not only is it linked to global warming, carbon dioxide is also shown to cause acidification and warming of the oceans.


What are some examples of climate change?

The following are the example for observed climate change:

  • Since the pre-industrial period, the global average surface temperature has risen by around 1°C.
  • In the second part of the twentieth century, there was a decrease in snow cover and sea ice extent, as well as the retreat of mountain glaciers.
  • Global average sea level rise and ocean water temperature rise.
  • Average precipitation is expected to rise across the Northern Hemisphere’s middle and high latitudes, as well as over tropical land regions.
  • Extreme precipitation events are becoming more frequent and intense in various parts of the world.

The following are the example for physiological and ecological changes that are linked to climate change:

  • Permafrost thawing
  • In the middle and high latitudes, the growth season is lengthening.
  • Plant and animal ranges are shifting poleward and higher.
  • Some plant and animal species are on the decline.
  • Trees begin to bloom earlier.
  • Insects are emerging earlier.
  • Birds deposit eggs earlier.

What are aerosols and how do they contribute to climate change?

When gases, dust, smoke, or fumes reach dangerous quantities in the atmosphere, it is called air pollution. Aerosols are tiny atmospheric particles that are floating in our atmosphere and constitute a type of air pollution.

Aerosols come in two forms: solid and liquid. The majority are caused by natural processes such as volcanoes erupting, but some are also caused by human industrial and agricultural operations.

Aerosols have an impact on global warming that can be measured. In cloudless air, light-colored aerosol particles can reflect incoming solar radiation while dark particles absorb it. 

Aerosols have historically had a global net impact of somewhat offsetting the rise in global mean surface temperature. Aerosols can alter the amount of energy that clouds reflect and alter atmospheric circulation patterns.

Several climate intervention (also known as “geoengineering”) ideas for decreasing global warming involve reflecting the sun’s energy away from Earth using atmospheric aerosol particles. 

Because aerosol particles do not linger in the atmosphere for extended periods of time, while global warming gases do, cumulative heat-trapping gases will outweigh any temporary cooling provided by short-lived aerosol particles.

Can an individual do something about global warming?

Yes. While large-scale government action at the national level is required to win the battle, we also need the aid of individuals who are ready to speak up, hold government and business leaders accountable, and modify their everyday behaviours.

Do you want to know how you can help in the battle against global warming? Take a few simple ways to reduce your personal carbon footprint: Make energy conservation a part of your everyday routine and purchase decisions. 

Look for the government’s logo on new appliances like refrigerators, washers, and dryers; they satisfy a higher level for energy efficiency than the minimal federal requirements.

When shopping for a car, aim for one that gets the best gas mileage and emits the fewest pollutants. When possible, you may also limit your emissions by utilising public transit or carpooling.

While the new federal and state regulations are a start in the right direction, there is still much more to be done. 

Make your voice heard in favour of climate-friendly and climate-change readiness measures.

Furthermore, remind your legislators that a just transition from filthy fossil fuels to clean energy should be a key priority, as it is critical to the development of healthy, secure communities.

You also don’t have to do it alone. Climate action can build community, be led by those on the front lines of its effects, and create a future that is equitable and just for all, as demonstrated by movements around the country.


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