Did you know that climate change has always existed?

We thought about doing an end-of-year history session to understand when we first had clues that something was changing in terms of climate and the environment, and the answer was surprising! The first recorded climate changes date back to 2100 BC. Let's just say that, at that time, it wasn't really man's fault.

Fear of extreme weather conditions has always existed.

The Earth has been facing climate change since its inception. One of the most important works of world literature, the Epic of Gilgamesh from ancient Mesopotamia (circa 2100 BC), is a good example of this. The main character is King Gilgamesh, who ruled the city of Uruk (The OPEC Fund for International Development). He wants to live forever, so he meets the boatman, Utnapishtim. Utnapishtim tells him that the gods are preparing a terrible flood. ‘Destroy your house, build a ship; abandon your riches, seek life; do not be greedy, save your life. Bring all kinds of living creatures into the ship you are building.’ It's a bit like the story of Noah.
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Yes, climate change has always existed, but when did we begin to perceive that things were changing more continuously?

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There are several key dates. Let's review them step by step.

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1896: Svante Arrhenius and the Industrial Warming Hypothesis

Long before CO₂ was systematically measured, Arrhenius was the first scientist to theorize that the industrial combustion of coal could significantly amplify the natural greenhouse effect. He provided a quantitative, though rudimentary, calculation of the potential warming that would result from a doubling of atmospheric CO₂. This work framed the entire global warming debate for the next century, establishing the first scientific benchmark for temperature sensitivity.

1938–1958: The Truth and the Proof

A little-known amateur scientist named Guy Callendar made history when he discovered that the planet had warmed. In 1938, the steam engineer Callendar took a break from his daily work and began meticulously collecting data from 147 weather stations around the world. Performing all his calculations by hand, he discovered that global temperatures had risen by 0.3°C over the previous 50 years. Like his predecessor Arrhenius, Callendar argued that carbon dioxide emissions from industry were responsible for global warming. However, his findings were largely ignored by other scientists.

It was the discovery of the Keeling Curve in 1958 that provided the first undeniable quantitative evidence that human activity was changing the atmosphere. By launching daily, meticulous measurements at Mauna Loa, Charles David Keeling visually documented the accelerated rise in CO₂. These data transformed the global warming hypothesis into a measured reality, providing the most iconic symbol of human impact on the planet.

1967: First Accurate Computer Climate Model

The model (a scenario for projecting the future based on present-day data) created by Manabe and Wetherald was the first to accurately treat Earth's atmosphere, oceans, and clouds as an interconnected system. It provided a reliable prediction: a doubling of CO₂ would lead to a 2°C temperature rise. The fact that this early model's prediction remains highly consistent with the complex simulations of modern supercomputers has established modeling as the essential tool for projecting future risks and guiding policies.

1987: Repairing the Ozone Layer

The adoption of the Montreal Protocol on substances that deplete the ozone layer on September 16, 1987, marked a turning point in environmental history. The ozone hole reached its largest single-day extent of the year on September 9, 2025, at 22.86 million square kilometers—about 30% smaller than the largest hole ever observed in 2006, which had an average area of 26.60 million square kilometers.

1988–1997: The IPCC and the Kyoto Protocol

The creation of the Intergovernmental Panel on Climate Change (IPCC) marked the transition from a purely scientific topic to a global political issue. The IPCC's sole objective is to synthesize the work of thousands of scientists worldwide into clear, policy-relevant reports. It provided a unique, unified, and authoritative scientific voice, building the trust and credibility needed for national governments to negotiate coordinated international policy actions.

In its second assessment report, the IPCC made the definitive statement that “the balance of evidence suggests a perceptible human influence on the global climate.” This was the moment when the consensus shifted from “it could happen” to “it is happening, and we are responsible.” This scientific claim provided the direct basis for the 1997 Kyoto Protocol, marking the start of international efforts to reduce emissions.

2015: The Paris Agreement

The Paris Agreement represents global consensus on a specific goal for planetary security. Unlike previous treaties, 195 nations committed to the ambitious target of limiting warming to 1.5°C. This agreement shifted the global framework from top-down mandates to bottom-up nationally determined contributions, ensuring nearly universal participation and establishing a crucial symbolic threshold to avoid the most catastrophic climate tipping points.

2025: Majority of Renewable Energies

Renewables overtook coal as the world's main source of electricity in the first half of 2025—a historic first. Global electricity demand is rising, but growth in solar and wind energy has been so strong that it covered 100% of the additional demand, even contributing to a slight decline in coal and gas use. The world generated nearly a third more solar power in the first half of 2025 compared to the same period in 2024, meeting 83% of the global increase in electricity demand.

Timeline of the Future of Climate Change

To conclude, a chronology of future actions planned by government agencies (and more) shows that, although we must continue improving, significant progress has been made—and more is in the works.

We are in the process of implementing the following:

• 2025–2027: Massive deployment of terminals and mandatory battery recycling.
• 2026–2034: Market for “rights to pollute”—the EU Emissions Trading System (EU ETS). The EU now plans to phase out “free quotas” from the carbon market from 2026 to 2034.
• 2030: 55% reduction in emissions from new cars in Europe.
• 2030: The IMO (a UN agency dealing with maritime navigation and its decarbonization) confirms its goal of reducing the carbon footprint of global maritime transport by 20% compared to 2008 levels.
• 2035: The EU Maritime Fuel Regulation makes shore-side electricity mandatory in major EU ports to limit emissions from port operations.
• 2035: Theoretical end of sales of new combustion-engine cars in the EU.
• 2050: The European Union aims to be climate-neutral by 2050. This carbon neutrality is one of the pathways outlined in the Paris Agreement to limit global warming to below 2°C compared to pre-industrial levels.

Source: https://www.bbc.com/news/science-environment-15874560

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