What can the ‘Great Dying’ teach us about climate change

Our planet's climate is changing at an unprecedented rate, with extreme weather events becoming more frequent and severe. The primary catalyst behind these dramatic shifts is human-induced climate change, stemming from the substantial release of carbon dioxide into the atmosphere. This is radically altering the Earth’s climate systems at a rapid and alarming rate.

Nevertheless, our planet has witnessed similar challenges in the distant past. Over 250 million years ago, the Earth experienced the Permian-Triassic Mass Extinction, also known as the ‘Great Dying,’ which nearly wiped out all forms of life. Scientists now believe that there are valuable lessons to be gleaned from this catastrophic event, providing warnings of what could become of us if we don’t get a handle on the climate crisis.

👉 In this article, we'll examine how the 'Great Dying' offers crucial insights into today’s escalating climate change and biodiversity crisis.

Over 250 million years ago - before dinosaurs even walked the face of the Earth - life was flourishing; trees, plants, lizards, proto-mammals, insects, fish, mollusks, and microbes all called our planet home. However, paleontologists have made a striking discovery: rock samples show a world teaming with life over 250 million years ago, but just after this point they all but vanish. This indicates that at some point around this time, almost all life on Earth was wiped out in some kind of mass extinction event - something we now refer to as the ‘Great Dying’. Scientists believe that it was the most catastrophic extinction event in the Earth’s history, as no class of life was spared. It’s thought that around 90% of marine species and 70% of land species were wiped out!  

So what caused this mass extinction? 

Given how long ago the Great Dying took place it’s incredibly hard for scientists to pin down an exact cause - there are very few rocks on Earth that are old enough to provide clues as to what happened. 

Some believe that an asteroid impact might have set off a cataclysmic extinction event on Earth. A group of scientists, backed by NASA funding, assert that they have potentially unearthed evidence to validate this hypothesis, claiming to have detected remnants of such a colossal collision. Nonetheless, this viewpoint is met with skepticism from other researchers. They believe that, even if an asteroid did make contact with our planet, it likely played a supplementary role in the unfolding crisis. These experts point to ongoing, severe volcanic activity that was already impacting Earth at the time, suggesting a more complex interplay of destructive forces.

The prevailing scientific consensus links the catastrophic events of the Great Dying to the massive flood basalt eruptions that gave rise to the Siberian Traps - an extensive expanse of volcanic rock situated in Siberia, Russia. Vast quantities of molten lava surged forth from a rupture in the Earth's crust, engulfing a region vast enough to span more than half the landmass of the United States of America. This cataclysmic event scorched the landscape, cloaked the atmosphere in a veil of dust, and unleashed huge amounts of greenhouse gases which disrupted the Earth’s finely tuned carbon cycle.

👉 To learn what the carbon cycle is and the crucial role it plays in maintaining the Earth’s atmosphere take a look at our article.

The release of colossal volumes of greenhouse gases, particularly carbon dioxide and methane, during the formation of the Siberian Traps is believed to have triggered extreme changes to the Earth’s atmosphere. These gases, once released into the atmosphere, created a potent greenhouse effect, trapping heat and drastically elevating global temperatures - atmospheric temperatures are believed to have been almost 10 degrees Celsius higher than they are today!  

This prolonged elevation in carbon dioxide levels and temperature significantly altered the Earth’s climate, resulting in devastating consequences for life across the globe. Approximately 90% of marine species and 70% of land animals died off, a massive loss that spanned from larger mammals and trees to insects and microorganisms. The extreme conditions created by these climate changes made the planet nearly uninhabitable, causing widespread disruptions in ecological systems.

The extinction event triggered a collapse in food chains and ecosystems. Predators lost their prey, plants lost their pollinators, and the balance that sustained various species was lost. The sharp decrease in biodiversity meant that fewer organisms were available to perform essential functions like decomposing waste, filtering water, and producing oxygen.

The Earth’s oceans suffered profound changes as well. The increased acidity of the seawater disrupted the life cycles of many marine species, particularly affecting organisms that relied on calcium carbonate for their shells and skeletons. As the ocean’s oxygen levels plummeted, areas devoid of oxygen expanded, creating dead zones where life was nearly impossible.

On land, the increased temperatures and disrupted ecosystems led to the disappearance of many plant and animal species, altering habitats and reducing the availability of resources. The loss of trees and plants, crucial for absorbing carbon dioxide and providing oxygen, further exacerbated the decline in atmospheric quality.

It took only 100,000 to 200,000 years for such mass extinction to occur, but it would take millions of years for the planet to recover from the Great Dying, with ecosystems slowly rebuilding themselves and species gradually evolving to adapt to the new conditions. This period of recovery underscores the resilience of life but also highlights the severe impact that drastic climate changes can have on the Earth’s biological and ecological systems.

👉 To learn more about the harmful impacts of ocean acidification head over to our article. 

Human-induced greenhouse gas emissions are driving significant changes to the Earth's climate, primarily due to the substantial quantities of carbon dioxide being released into the atmosphere. This increase in atmospheric CO2 is contributing to a noticeable warming of the planet. Over the course of the last century, we have observed an approximate increase of 1 degree Celsius in global temperatures, and scientists project that should current emission rates persist, we could witness a temperature surge ranging from 3 to 5 degrees Celsius by the century's close.

Current levels of carbon dioxide fall far short of the levels seen during the height of the Great Dying - at its peak carbon dioxide concentration is estimated to have reached 7,390 ppm (parts per million), whereas these days carbon dioxide levels are at around 415 ppm. However, what’s concerning is that just before this period of mass extinction, carbon dioxide levels in the atmosphere were only around 440 ppm, much closer to today's levels. This has caused many to draw parallels between the Great Dying and our current situation. 

It should be noted that the elevated levels of carbon dioxide that triggered the Great Dying were sustained for thousands of years - which means that we still have time to correct course before suffering a similar fate. Yet the takeaway is clear - prolonged elevation of carbon dioxide levels is disastrous for the environment.

We’re already living through the life-threatening impacts of climate change after just a couple of hundred years of elevated carbon dioxide levels. Every year we’re seeing more frequent and extreme heat waves, more widespread and out-of-control forest fires, and more intense and devastating flooding. 

And we’re not the only species to be impacted, climate change is impacting biodiversity too - numerous species face habitat loss, altered migration patterns, and heightened vulnerability to diseases. Our planet's flora and fauna are grappling with unprecedented challenges, forced to adapt, relocate, or perish. This alarming loss of biodiversity, reflecting patterns witnessed during the ‘Great Dying,’ is undermining crucial ecosystem services, further amplifying the effects of climate change.

Much like during the Great Dying, we’re also beginning to witness the acidification of our oceans. A whole host of different species - from shellfish to plankton to fish are beginning to feel the effects. In fact, 14% of the world's coral was already lost in the period between 2009 and 2018, and a further 70 to 90% could be gone by 2050 unless we limit global warming. 

In another frightening parallel to the Great Dying, some regions of the oceans are also so low in oxygen that they’re considered to be dead zones in which no species can survive. Worryingly, these areas seem to be expanding. 

It's crucial to recognize that these impacts are being felt with just 1 degree of global warming, if we continue on our current trajectory the impacts only get more and more extreme as the Earth continues to heat. 

What’s particularly concerning is that the current release of heat-trapping carbon dioxide is higher than it was at the end of the Great Dying. According to experts, our emissions are 10 to 20 times higher. 

Essentially, if we continue to release such high levels of carbon dioxide into the Earth’s atmosphere, we risk creating a climate that is similar to that of the Permian-Triassic extinction, and potentially in a much shorter period of time. The effects would be devastating, and can we expect huge portions of life on Earth to be driven to extinction.

❗️Scientists warn that the Great Dying is a view into our own future if we don’t take urgent action to reduce carbon emissions. 

👉 To discover why climate change is considered to be the challenge of the century head over to our article.

The parallels between the 'Great Dying' and our current climate crisis are stark and undeniable, providing us with a crucial lesson: unchecked climate change can have catastrophic consequences for life on Earth. The rapid rate at which we are currently emitting greenhouse gases surpasses that of the Permian-Triassic period, putting us on a precarious path. While our technology and understanding of climate science have advanced significantly, the complexity and magnitude of climate change demand immediate and sustained action.

At Greenly we can help you to assess your company’s carbon footprint, and then give you the tools you need to cut down on emissions. Why not request a free demo with one of our experts - no obligation or commitment required. 

If reading this article has inspired you to consider your company’s own carbon footprint, Greenly can help. Learn more about Greenly’s carbon management platform here.