When you think about human-caused climate change, industrial smokestacks and cars from the 20th century likely come to mind.
But here’s a surprising revelation: the warming of our planet started not in the mid-1900s, but as far back as the 1830s.
That’s nearly a century earlier than previously assumed, reshaping our understanding of humanity’s long-standing impact on Earth’s climate.
“It was an extraordinary finding,” says Nerilie Abram from the Australian National University. “It was one of those moments where science really surprised us.
But the results were clear. The climate warming we are witnessing today started about 180 years ago.”
Beyond the Northern Hemisphere
Historically, climate reconstructions have focused on the Northern Hemisphere, relying primarily on land temperature records.
But as Abram’s team noted, this approach overlooks vast portions of the planet.
To gain a fuller picture, they turned to the Southern Hemisphere, exploring climate records in some of Earth’s most remote regions.
The team combed through evidence preserved in corals, tree rings, and ice cores, compiling data from the past 500 years.
By combining this with thousands of years of climate model simulations, they reconstructed global temperature trends, revealing a startling pattern: temperatures began rising globally in the 1830s, coinciding with the early days of human industrial activity.
Rewriting the Timeline of Climate Change
Until now, the “time of emergence”—the point when human-caused climate change became distinguishable from natural variability—was pinned to the 1930s.
This was based on studies of the Arctic, where rapid warming due to industrial emissions had begun to stand out.
But Abram’s research challenges this assumption. Their findings show that significant, sustained warming was already underway by the 1830s.
As greenhouse gas emissions began to rise during the early stages of industrialization, temperatures in tropical oceans and the Northern Hemisphere’s atmosphere followed suit.
The Southern Hemisphere’s warming lagged by about 50 years, starting near the turn of the 20th century.
This earlier timeline changes our understanding of how quickly Earth responds to even small increases in greenhouse gases.
“The changes in greenhouse gases in the 19th century were small compared with the fairly rapid changes we see now, so seeing the climate respond this way was a surprise,” Abram told The Guardian.
A Shift in Perspective
Here’s where the findings disrupt conventional thinking: many assume that only large-scale industrial activities with massive emissions can trigger noticeable climate change.
Yet, the 19th century’s relatively modest emissions still managed to warm the planet.
This suggests that Earth’s climate is far more sensitive to human interference than previously believed.
At first glance, this revelation might seem discouraging. After all, it implies that our impact on the planet has been longer-lasting and potentially more damaging than we realized.
However, it also underscores a critical point: small changes in emissions can have significant effects.
This means that efforts to reduce emissions today—even incremental ones—can make a meaningful difference.
The Long Shadow of Industrialization
Abram’s findings are a reminder that industrialization’s environmental costs began accruing long before modern climate awareness.
By the mid-19th century, coal-burning factories and deforestation were already adding carbon dioxide to the atmosphere.
These early emissions might seem insignificant compared to today’s levels, but they set the stage for the dramatic warming we now face.
The tropical oceans, which play a crucial role in regulating global temperatures, were among the first to feel the effects.
Warming in these regions had cascading impacts, influencing atmospheric patterns and amplifying changes in other parts of the world.
The Southern Hemisphere, with its vast oceans and relatively sparse landmass, responded more slowly but eventually followed a similar trajectory.
Lessons for Today’s Climate Crisis
This historical perspective highlights both the urgency and the opportunity in addressing climate change.
If small increases in greenhouse gases could trigger warming in the 1830s, then reducing emissions today could help stabilize the climate more effectively than many might assume.
Abram’s research also underscores the importance of looking beyond the usual data sources.
By including the Southern Hemisphere and less-studied regions, her team was able to uncover a more complete and nuanced picture of Earth’s climate history.
This holistic approach is essential for designing effective solutions to the global climate crisis.
A Call to Action
The implications of this study are clear: humanity’s impact on the planet began earlier than we thought, and our actions today will shape the climate for generations to come.
While the timeline of climate change might be longer than we realized, it’s not too late to rewrite its future.
As Abram aptly puts it, “The climate warming we are witnessing today started about 180 years ago.”
This means that the choices we make now—whether to continue on our current path or to adopt more sustainable practices—will be felt for centuries to come.
History has shown us the power of human activity to alter the planet. Let’s use that power wisely.
