Most readers will be familiar with carbon dioxide, mainly due to its negative association with global warming. We take a closer look at this gaseous substance and its impact on the weather and climate.

Carbon dioxide is a gas that has been present in Earth’s atmosphere throughout its history, but only came to widespread public attention late in the 20th century, when the connection between fossil fuel emissions and global warming became widely recognised.

Yet, few of us really know what precisely carbon dioxide is, never mind the role it plays in our environment. In this article, we take a closer look at what it is and the role it plays in global warming and climate change.

The excerpt in this introduction already provided a brief description of what carbon dioxide is, but before delving deeper, one needs a more detailed definition.

Carbon Dioxide Definition​​​​​​​​​

Carbon dioxide is a naturally occurring gas consisting of one carbon atom and two oxygen atoms. At normal atmospheric concentrations, it is generally harmless and plays an essential role in photosynthesis, during which plants absorb carbon dioxide and release oxygen. However, excess carbon dioxide from fossil fuel emissions acts as a greenhouse gas, contributing to global warming.

Carbon dioxide is essential for life on Earth, especially through its role in photosynthesis. Although it makes up only a small part of the atmosphere, too much carbon dioxide has a damaging effect on both weather patterns and the climate.

As mentioned in the introduction, it is because of the alarming rate at which carbon dioxide is building up in the atmosphere and its harmful long-term effects that we are so familiar with it in the first place.

Understanding the harmful effects of carbon dioxide is important for you to get a proper understanding of why it is such a widely discussed and controversial subject, and why certain groups of people go to extremes to reduce the emissions of this greenhouse gas.

But first, one needs to take a quick look at the factors responsible for the increase in carbon dioxide.

At this point, you may be wondering why carbon dioxide has been building up at such an alarming rate over the last century.

Carbon dioxide (CO₂) is naturally produced through processes like human/animal respiration and volcanic eruptions.

Human activity, however, is the biggest contributor to the increase in atmospheric CO₂. This includes activities like deforestation, but especially the burning of fossil fuels such as coal, oil, and petroleum-based fuels used in the transport industry and heavy industries.

By looking at how it directly affects individual components of weather and climate, you will be able to get a clear and realistic view of the widespread impact that raised levels of carbon dioxide have and how all these different components fit together to create a global crisis.

There is a very fine balance between the amount of carbon dioxide (CO₂) and atmospheric conditions. If concentration levels of carbon dioxide become too high, as is currently the case, the impact on the atmosphere can be devastating.

And like meteorologists and climatologists have been warning and providing evidence for decades, it is the climate and weather that are being affected the most.

In short, the effects of carbon dioxide in the atmosphere become increasingly pronounced as concentration levels rise. This is directly reflected in global warming and the resulting changes in the climate.

During the article’s introduction, carbon dioxide was called a greenhouse gas, but no further explanation was given as to what a greenhouse gas is.

First, if you don’t already know this, let’s quickly define what a greenhouse gas is. The name “greenhouse” refers to a building typically found in nurseries and other facilities where plants and trees are grown.

A greenhouse’s main purpose is to regulate the inside temperature to promote plant growth, primarily through transparent roofs and sidewalls that allow sunlight in while limiting the amount of warm air that can escape.

Carbon dioxide is called a greenhouse gas because it absorbs and re-emits some of the heat radiated from the Earth’s surface, slowing the rate at which this heat escapes into space. As carbon dioxide remains in the atmosphere for a long time, higher concentrations strengthen this warming effect.

Its long-lasting nature is due to the fact that it is removed from the atmosphere only gradually through natural processes such as absorption by the oceans and uptake by plants.

As a result, it becomes increasingly difficult for heat to escape into space, causing the atmosphere as a whole to slowly warm up.

As the name suggests, the rise in temperatures occurs across the globe but is especially evident in the polar regions. Throughout the rest of the world, regional record-high temperatures are being recorded on an almost annual basis.

With the sheer amount of research done and mountains of scientific evidence presented to us over the last couple of decades, there is no denying it. Global warming is very real and continues to pose an increased danger to all life on Earth.

And if, for some reason, you still question all evidence that the planet is warming at an alarming rate, consider the following small fact…

Since the late nineteenth century, the global surface temperature has increased by approximately 1.1° Celsius (2° Fahrenheit). And if you think this is a small and insignificant number, you will be gravely mistaken.

Global warming has very serious, long-term effects on climate and weather, as you are about to discover in the following sections.

It is very common to mistake weather and climate. In short, climate represents weather patterns and tendencies established over decades or more, while weather portrays the atmospheric conditions you are experiencing at any specific time and what is forecasted for the immediate future.

You may still find it difficult to differentiate the two and need more clarification. You can read an in-depth article about the difference between climate and weather in this article.

When we look at climate change, however, the term encompasses more than just atmospheric conditions. It also includes changes in the environment and related changes in natural behaviour.

But for climate change to take place at the alarming rate currently being observed, it relies on one critical factor, namely, global warming. Without the continued human-driven warming of the planet, climate change would not be occurring at its current rate.

We already established that global warming is very real, and so is climate change. The evidence of climate change is all around us, from increased extreme weather events to droughts occurring worldwide.

Making a statement like this may sound like pointing out the obvious to many readers. To more critical readers, however, this may sound a bit like unsubstantiated claims.

There are, however, some key indicators that climate change is not only taking place but also accelerating.

Apart from rising temperatures caused by global warming, there are a number of other indicators of climate change:

Sea levels have been rising steadily for more than a century. This can be seen as a direct result of global warming. Since 1880, the global sea level has risen by about 21–24 cm (8–9 inches).

What is most unsettling, though, is the fact that almost 10 cm of this rise has taken place since 1993. It means the rate at which sea levels continue to rise is accelerating.

The increase in the frequency and intensity of some extreme weather events is becoming more evident. Here are just a few examples from 2018 alone.

• • A temperature of 51.3° Celsius (124.3° Fahrenheit) was recorded in Ouargla, Algeria, setting a new national record and possibly the highest reliable temperature ever recorded in Africa.

  • Extensive flooding and landslides due to unusually heavy rainfall in Japan led to the loss of 237 lives, while millions of people were advised or ordered to evacuate their homes.

  • The United States experienced Hurricanes Florence and Michael, two of the most destructive hurricanes in the country’s history. Meanwhile, Typhoon Mangkhut caused mass destruction in Hong Kong and the Philippines.

  • California in the United States experienced the Camp Fire, the deadliest and most destructive wildfire in the state’s history, amid persistent dry conditions and strong winds. This led to the loss of 85 lives.

The Greenland and Antarctic ice sheets have been losing mass for decades, but the rate at which this loss has taken place has accelerated significantly in recent decades.

For example, between 2002 and 2025, Greenland experienced an average loss of approximately 264 billion tons of ice every year. During the same period, Antarctica experienced an average loss of approximately 135 billion tons every year.

Like the accelerated rise in sea level, it is the increasing rate at which ice is being lost that is so disconcerting. In Antarctica alone, research found that the rate of ice loss had tripled by 2017 compared with earlier decades.

Glaciers in Scandinavian and other northern countries near the Arctic Circle are beautiful features that attract visitors from across the world every year. Many of these frozen “rivers of ice” are literally thousands of years old!

The “toe” or “snout” is the end of a glacier and is called the terminus. As the climate warms and the glacier loses ice, the terminus may retreat, with the resulting meltwater flowing into rivers and oceans or collecting in lakes at the edge of the glacier.

This “receding trend” has been going on since the start of the twentieth century, and glaciers have been retreating at an alarming rate ever since. This is happening in all the areas famous for their glaciers, including the Himalayas, Mount Kilimanjaro, the Alps, the Rocky Mountains, and parts of the Andes.

The accompanying picture of the Briksdal glacier in Norway (taken in 2003 and then again in 2008) is a perfect illustration of how climate change is contributing to the recession of glaciers worldwide.

Over the last five decades, a decrease in snow cover has been observed over the Northern Hemisphere. This is especially evident during late spring and early summer, particularly in May and June.

Not only is the overall snow cover less, but it also starts to melt earlier than it did in previous decades. The most rapid declines have been observed during June.

This is very significant, as roughly a third of the world’s land surface can be covered in snow during parts of the year. As the white-coloured snow reflects the sun’s radiation away from the planet’s surface, it shields the surface from being heated by the sun.

With less snow present to reflect the heat away, larger areas of the surface are now exposed to absorb the heat, which contributes to global warming and accelerates climate change.

These are just five examples used to highlight the reality and impact of climate change.

Climate skeptics will still question whether climate change is as real and threatening as the scientific community makes it out to be.

The trends discussed above are direct consequences of global warming and climate change, driven largely by the buildup of carbon dioxide and other greenhouse gases. Together, they help to reinforce the reality of climate change and the dangers associated with it.

Carbon dioxide is not the direct cause of specific weather events such as thunderstorms, heatwaves, or droughts. Instead, the increasing concentrations of this greenhouse gas gradually warm the atmosphere and large bodies of water, changing the conditions in which weather develops.

A warmer atmosphere can hold more water vapour, which can lead to heavier rainfall when condensation and precipitation take place. At the same time, higher temperature levels increase evaporation from the soil, vegetation, and bodies of water, which can worsen dry conditions and contribute to more severe droughts.

Rising temperatures also increase the probability of longer, more intense heatwaves. Warmer ocean water can provide tropical storms with additional moisture and energy, which increases the risk that some hurricanes and tropical cyclones become more powerful and result in heavier rainfall.

This does not mean that all extreme weather events are caused by carbon dioxide or climate change. It means that the buildup of carbon dioxide is changing the background conditions and making certain types of extreme weather more likely or more severe.

This article covered the different ways in which carbon dioxide contributes to global warming and climate change in direct and indirect ways.

The aim was to let one gain a better understanding of carbon dioxide, what it is, and the role it plays in global warming and climate change.

Until next time, keep your eye on the weather!