1.5ºC of Warming Reached: The Paris Agreement Revisited
1.5ºC of Warming Reached: The Paris Agreement Revisited
For the first time in recorded history, the world has surpassed the 1.5ºC threshold of warming for 12 months consecutively. Here, we look at what this means for the planet and for our political attempts to rein in rising temperatures.
Last month, environmentalists reeled as it was announced that we had surpassed a critical warming threshold for the first time in history. With data from the EU’s Copernicus Climate Change System (C3S) revealing that June was not only the hottest on record, but that it was the twelfth consecutive month to experiencing global average surface temperatures of 1.5ºC (2.7ºF) above pre-industrial levels, many are assessing what this represents for humanity’s progress towards combating global warming.
Source: C3S Report
Specifically, the global average temperature for the past year (July 2023-June 2024) is the highest on record, at 0.76°C above the 1991-2020 average and 1.64°C above the 1850-1900 pre-industrial average. The areas that were most affected in Europe were in the southeast, including countries like Türkiye and Cyprus, with western Europe near or below average.
According to Dr. Carlo Buontempo, the Director of C3S, we are likely to continue seeing record-breaking temperatures as little is done to halt climate change.
“This is more than a statistical oddity and it highlights a large and continuing shift in our climate,” revealed Dr. Buontempo. “Even if this specific streak of extremes ends at some point, we are bound to see new records being broken as the climate continues to warm. This is inevitable unless we stop adding greenhouse gases into the atmosphere and the oceans.”
For anyone paying attention over the past year, it will come as little surprise that it has led to the shattering of a crucial warming threshold; across the world, temperature record after temperature record seems to have been broken. From the sweltering heatwaves that wracked the West Coast of America recently, to the 45ºC seen in the mediterranean, to the lethal temperatures that claimed over 1,300 lives during this year’s Hajj pilgrimage, everywhere in the world is at risk from rising temperatures.
But many might wonder why a figure such as 1.5ºC represents such a watershed moment in the history of global warming, as it seems like a relatively arbitrary number. So, why is it important?
1.5ºC of Warming: A History
This figure is generally held up as the best-case warming scenario, the point after which the worst effects of climate change will likely kick in, with more extreme and frequent weather events taking place, including heatwaves, wildfires, and drought. Each of these, in turn, threatens to destabilise ecosystems and habitats around the world, leading to the destruction of ecosystems and potentially forcing the displacement of hundreds of millions of people.
It rose to prominence in the political discourse during the Paris Agreement 2015, when international lawmakers committed to the legally binding target to "pursue efforts" to limit global temperature rises to 1.5ºC, and maintain them "well below" 2.0ºC above those recorded during the pre-industrial period.
Yet, throughout the history of international climate conferences and treaties, it has seemed that the de facto limit, under which international policymakers would attempt to keep temperatures, was approximately 2ºC of warming. This was first put forward in the 1970s, surprisingly by economist William Nordhaus who, in a pair of groundbreaking papers, warned that 2ºC of warming or more could push “the climate outside of the range of observations which have been made over the last several hundred thousand years.”
Subsequently, at the landmark 1997 Kyoto Summit, governments bindingly agreed (with some notable exceptions) to reduce greenhouse gas concentrations in the atmosphere to "a level that would prevent dangerous anthropogenic interference with the climate system", with many contextualising this within the 2ºC figure.
This was later enshrined within the Cancun Agreements of 2010, which committed governments to “hold the increase in global average temperature below 2°C above pre-industrial levels.”
Yet, the evidence supporting the notion that 2ºC of warming is the critical threshold beyond which climatic changes will prove calamitous was relatively unsupported. This changed in 2015 with the publication of a critical report, bringing together the views of 70 scientists in a process called the “structured expert dialogue”, that highlighted the inadequacy of the 2ºC goal.
It noted that levels of warming seen at the time - approximately 0.82ºC - was already intolerable in many parts of the world, instead suggesting that 1.5ºC would be preferable in light of the science, in an effort to avoid some of the more severe impacts of climate change.
This report would subsequently serve as the basis for the draft agreement put together that same year at the Paris Summit.
What does this level of warming mean?
It must be noted that, despite there being plenty of evidence demonstrating what this level of warming could mean for the global climate system, the figure itself is still an arbitrary aspiration. It is well established that every 0.1ºC of warming will translate into a deepening climatic crisis, with 1.4ºC clearly a better aspiration than 1.5ºC, and so on. Yet, it is simply a figure that is feasible under best-case climate models (stipulating the most stringent reductions in emissions) that would also limit the worst effects of climate change.
That said, since the 2015 agreement there has been a flurry of research into the effects of different warming scenarios on our environment. One key piece was commissioned in 2018 by the Intergovernmental Panel on Climate Change (IPCC), their ‘special report on climate change at 1.5ºC’, which outlined the importance of limiting warming to this threshold.
Key findings from the report include:
Warming is asymmetric around the world, with 20-40% of the global population living in regions that have already experienced warming of more than 1.5C in at least one season (as of 2018).
Temperature rises before 1.5ºC is hit are already resulting in “profound alterations to human and natural systems, bringing increases in some types of extreme weather, droughts, floods, sea level rise and biodiversity loss, and causing unprecedented risks to vulnerable persons and populations.”
Warming of 1.5ºC will see more extreme weather events across the world, with extremes of heat most prevalent in specific regions, including North America, central and southern Europe, the Mediterranean region, western and central Asia, and southern Africa.
The 1.5ºC scenario will see around 420 million fewer people being frequently exposed to extreme heatwaves than the 2ºC scenario.
Global sea levels will be approximately 10cm lower in a 1.5ºC scenario than 2ºC, which might lead several regions to become uninhabitable.
Damage to ecosystems and farmland is likely to contribute to food insecurity and malnutrition, “especially in regions such as the African Sahel, the Mediterranean, central Europe, the Amazon, and western and southern Africa”.
Therefore, we can see the impacts on societies around the world, whilst suffering a number of consequences in both scenarios, are most detrimental the greater the level of warming. It is thus worrisome to many that the best-case scenario seems more and more out of reach, particularly when the 2018 report estimated we would reach this limit between 2030-52.
We must make clear that this does not mean the figure has been permanently breached nor has the Paris Agreement necessarily failed; with the record-breaking heat of 2023 having been, at least in part, fuelled by a particularly strong El Niño, it is plausible that we have not reached a ‘new normal’ with regards to annual temperatures.
That said, many environmentalists are already calling this a watershed moment where we must take stock of our progress towards achieving the targets of Paris. This is compounded by the first global stocktake of the Paris Agreement, conducted just last year, which concluded that countries are not on track to meeting their legally binding obligations.
According to reporting from Sky News, Isabella O’Dowd, Head of Climate at the WWF, shared that the 1.5C temperature breach is "not a milestone towards an inevitable destination, but a wake-up call for the new government,” referencing the incoming Labour government in the UK.
Conclusion
Having breached the 1.5ºC threshold does not mean that we have failed in our commitments to limit warming, as this does not definitively represent us having transitioned permanently above this limit. However, it is certainly a wake-up call that underscores our previous inability to meet the targets we as an international community laid out for ourselves almost ten years ago.
What this shows us here at Shade the UK is the unfortunate fact that climate adaptation is becoming a growing necessity in our toolkit to fight the worst effects of climate change. As targets are consistently missed with regards to emissions levels and the degree of warming, our new reality is one in which treating the effects of climate change and not necessarily the root cause will have to take a more central role.
We therefore call on the new UK government, and all international legislators, to consider policies that will allow us to combat the worst effects of global warming, particularly in our lived environments.
Written by Oliver Longstaff
