The Amazon rainforest is often called the “lungs of the earth” because of its crucial role in producing oxygen and absorbing carbon dioxide.
In fact, the Amazon rainforest is home to a huge collection of plant and animal species, including trees, which perform photosynthesis.
During this process, plants take in carbon dioxide from the atmosphere and release oxygen. The Amazon is estimated to produce around 6%-20% of the world’s oxygen, making it a vital oxygen source (more on that later, and why it’s a controversial statement).
Not only does it produce oxygen, but it also serves as a significant carbon sink. This means it absorbs and stores enormous quantities of CO2, helping offset the effects of greenhouse gas emissions that contribute to climate change.
The dense vegetation in the Amazon absorbs carbon dioxide through photosynthesis and stores it in plant tissues and soil.
In conclusion, because of how much the Amazon contributes to producing oxygen and absorbing CO2, this tropical rainforest is referred to as “the lungs of the earth.”
How big is the Amazon?
The Amazon rainforest is vast and covers a substantial area. It spans multiple countries in South America, primarily Brazil, but also parts of Peru, Colombia, Venezuela, Ecuador, Bolivia, Guyana, Suriname, and French Guiana.
The exact size of the Amazon varies slightly depending on how it’s defined, but it generally covers approximately 5.5 million square kilometers (about 2.1 million square miles).
This makes it the largest tropical rainforest on the planet and one of the most biodiverse areas on Earth.
But is this really true? Is Amazon, in fact, “the lungs of the earth?”
Not everyone believes we should slap this term on Amazon and call it a day. A 1998 study by Science magazine estimates that the Amazon rainforest produces only around 6% of the planet’s oxygen.
That’s a far cry from the 20% we so often read and hear about. Then there are researchers like Philippe Ciais, who think it’s closer to 10-12%.
There’s also the fact that isn’t mentioned often that almost all the oxygen the rainforest produces is consumed by the very same trees through photosynthesis.
During the day, plants, including trees in the Amazon, undergo photosynthesis. In this process, they take in carbon dioxide and release oxygen while producing glucose (sugar) as an energy source. This is the primary way in which oxygen is generated in the rainforest.
At night, plants breathe, similar to animals. They use some of the oxygen produced during the day to release energy from stored sugars.
While it’s true that trees and other vegetation in the Amazon consume oxygen during the nighttime respiration process, the net effect over a 24-hour period is oxygen production.
In other words, the overall oxygen production through photosynthesis during the day far outweighs the oxygen consumed at night. Barely.
The Amazon rainforest is critical to the planet’s environmental balance. Still, it’s not the sole source of oxygen production.
Its role in the global carbon cycle is just one part of a larger system that includes oceans, other forests, and various ecosystems.
If the Amazon isn’t the most significant contributor to the world’s oxygen supply, what is?
According to the data from the Brazilian Institute of Forests (Instituto Brasileiro de Florestas), seaweed, a crucial part of the ocean’s plant life, “accounts for 54% of the world’s oxygen production and the seas act as climate regulators on the planet.”
They go as far as to say that “Without the services provided by the ocean, the temperature could exceed 100ºC and make life on Earth unfeasible.”
Therefore, the oceans, and seaweed in particular, should be referred to as “the lungs of the earth.”
In fact, the UN and UNESCO do call oceans “the lungs of the planet.”
Historically, phytoplankton in the oceans played a massive role in producing oxygen over millions of years through photosynthesis.
These tiny aquatic plants are like the unsung heroes of oxygen production. They’re responsible for nearly all of the oxygen we have in the atmosphere.
And this oxygen will last us millions of years, mind you.
Why is the Amazon really important?
So why do we place so much emphasis on the biggest rainforest in the world?
1) Biodiversity
The Amazon rainforest is renowned for its unparalleled biodiversity. It’s home to a staggering assortment of animal and plant species, many of which we can’t find anywhere else on Earth.
This biodiversity is not only valuable for scientific research (medicinal, especially) but also plays a crucial role in ecological balance and the resilience of ecosystems.
2) Carbon sink
Second, the Amazon acts as a substantial carbon sink, absorbing and storing huge amounts of carbon dioxide from the atmosphere.
Trees and vegetation in the Amazon absorb carbon dioxide and store it in their tissues and soil.
This helps mitigate the effects of greenhouse gas emissions and contributes to climate stability.
3) Impact on local and global climate
The Amazon has a profound impact on climate patterns, both locally and globally. Locally, it generates moisture through transpiration and releases it into the atmosphere.
This contributes to rainfall patterns in the region. The moisture also helps maintain the Amazon’s own ecosystem and water cycle.
Globally, the Amazon plays a role in regulating the Earth’s climate by influencing weather patterns and atmospheric circulation.
Deforestation and changes in the Amazon’s climate can have far-reaching consequences for weather systems, including droughts and altered rainfall patterns in regions far from the Amazon.
Final thoughts
Scientifically, it’s more accurate to describe the Amazon rainforest as an essential contributor to oxygen production and a significant carbon sink instead of crediting the entire function of the “lungs of the earth” to it alone.
The term “lungs of the earth” is a metaphor that highlights the Amazon’s significant role in oxygen production and carbon dioxide absorption.
As we know, metaphors are useful for conveying complex ideas in simple terms. That’s why we use this metaphor to emphasize the rainforest’s importance.
