Understanding 1.5°C

You've probably seen "1.5C" in the news, especially leading up to COP28, the big UN climate talks in Dubai. It's also part of your country's climate promises and on the Climate Clock in New York's Union Square, reminding us about the climate crisis.

Now, what's this "1.5C" everyone talks about? How do we measure it? Why is it important? And if we go over it, can we get back below 1.5C? Before the climate summit in Dubai, let's explore these questions and understand the significance of this climate figure.

??1.5°C?threshold:

It means that by 2100, the Earth's average surface temperature shouldn't increase more than 1.5C (2.7F) compared to pre-industrial levels. This 1.5C goal was set as an ambitious target in the 2015 Paris Agreement, where 195 nations pledged to address climate change. The agreement aims to cap global warming at "well below" 2C by the century's end and make efforts to keep it within the safer limit of 1.5C. "One-point-five has become an iconic figure," notes Sir David King, the former lead negotiator at the 2015 UN climate summit that led to the Paris Agreement.

Source of ?1.5°C?limit:

The 1.5C target in the Paris Agreement surprised many. Myles Allen, a professor at the University of Oxford, thought it was more ambitious than expected. This goal was set after studying the impacts of climate change at different warming levels. The IPCC report showed that at 1.5C, extreme heat is less common than at 2C. Even the coldest nights warm up less—by about 4.5C at 1.5C compared to 6C at 2C. Before Paris Agreement, there wasn't a clear goal to reduce climate change. Pauline Dube, an environmental scientist, sees the agreement as a significant step in the climate change community.

?Did we cross it?

In 2023, it's shaping up to be the hottest year ever. July was the hottest in 120,000 years, and September set a record too. The daily global temperature exceeded 1.5°C compared to preindustrial levels for about a third of 2023. That's a lot of days over the 1.5°C limit!

However, there's a crucial difference between daily temperature and the long-term average. When we discuss the 1.5°C threshold at COP28, we mean the average over a decade. It's tricky to measure, and we know it within about a tenth of a degree. Looking at specific regions, we see 1.5°C exceeded locally. The Arctic warmed four times faster than the rest of the world since 1979. Africa also warmed faster than the global average in recent decades.

?Understanding 1.5°C compared to 1°C and 2°C

According to Allen, the difference between 1.5°C and 2°C is much more significant than the gap between 1°C and 1.5°C. As temperatures rise, the impacts worsen, and the rate at which they worsen per degree increases.

To simplify, each tenth of a degree matters, but as temperatures go up, each increment becomes more critical. Allen explains this by noting that the world's ecosystems and economies evolved to adapt to the climate of the late 19th and early 20th centuries. This historical climate is what our ecosystems have experienced for thousands of years, and it's the environment in which our economies developed.

?Changing Predictions:

When countries adjust their climate change policies, estimates for reaching 1.5°C also change. This can happen with more or less ambitious plans. These estimates may also shift as scientists refine climate models using new analyses of historical climate data. For example, after the IPCC's 1.5°C report, a significant update occurred. Scientists found that we're now 0.2°C warmer than preindustrial levels. However, the lack of a formally agreed definition for long-term global heating leads to different interpretations of when the world will surpass the 1.5°C target set by the Paris climate agreement.

In the short term, reaching this temperature rise could happen very soon, perhaps even within the next few years. Yet, climate trends are measured over decades, not years. One proposed solution, suggested by Richard Betts of the UK Met Office’s Hadley Centre, is to combine the last ten years of global temperature observations with a forecast for the next ten years. This approach could provide a universally agreed measure of global warming, triggering immediate action to prevent further increases.

?Overshooting 1.5°C

Yes, according to King, we can, but it's not a good idea. King emphasizes that quickly cutting emissions is the safest way to avoid overshooting. However, as a last resort, we might need overshoot to remind us of the safe warming limit. To return below 1.5°C after overshoot, we'd need massive carbon capture, a method to take carbon out of the air and store it. King's Climate Crisis Advisory Group estimates this would require 10 to 15 billion tonnes of carbon dioxide yearly, much more than the entire greenhouse gas emissions of the EU in 2021.

To reverse overshoot, we'd need to use these technologies while also drastically reducing new emissions. However, these technologies are limited and expensive. Even if we did return to temperatures under 1.5°C after overshoot, critical systems like permafrost, sea levels, and ice sheets would take centuries to recover. Overshooting and then going back below 1.5°C would also be more costly than avoiding it altogether

?Ying and Yang of 1.5°C

Achieving the 1.5°C goal requires swift and unparalleled actions. According to Dube, the likelihood of achieving this target is almost gone based on the research's portrayal. In 2022, Bill Gates expressed doubt, stating there's "no chance" of staying within the 1.5°C threshold. However, he sees promise in climate innovations like carbon capture. Some media outlets declared it was time to bid farewell to 1.5°C. Pushing back, IEA executive director Fatih Birol called such declarations factually incorrect and politically wrong, insisting that achieving 1.5°C is still possible.

For nations reliant on minimal warming for survival, 1.5°C remains a central topic. Journalist Amy Martin likens giving up on 1.5°C to watching a fire burn without trying to put it out. Allen emphasizes that we're not doomed to 1.5°C warming; it's still possible to limit it. Allen estimates that fully abating fossil fuel CO2 emissions from 2022 would cost about $6tn, a fraction of the $13tn spent on fossil fuels in the previous year. This demonstrates that the financial resources to address the problem exist; they just need redirection.

?Silver lining if we stay on course

According to King, strong leadership from the US and China is a promising development post-COP28. Expressing its critical importance, King emphasizes the need for the US and China to present a strategy. King, who negotiated with their climate envoys in 2015, sees their recent agreement as a positive start, even though he believes it falls short. He anticipates that if the US and China take the lead, the European Union, India, Brazil (under President Luiz Inácio Lula da Silva), and others will follow suit.

?For Allen, positive tipping points, like advancements in renewable power and increased adoption of electric vehicles, signal accelerated decarbonization. Meanwhile, Dube hopes for a perspective shift recognizing the injustice of climate change driven by the Global North but affecting the Global South the most. This shift entails fair climate change tackling with ample support for adaptation and funding for climate-vulnerable nations. Dube underscores the need for a societal transformation at this crucial point of change.

?1.5°C Supply Chain

The decarbonization of supply chains is poised to revolutionize the game. By directing attention to emissions outside their immediate control, organizations can expedite the overall decarbonization of the economy. This may involve facilitating green purchasing options for customers or encouraging suppliers to take proactive measures, especially in regions where stringent climate legislation is yet to be implemented by governments. In the pursuit of sustainability, forward-thinking supply chain leaders recognize the imperative to collaborate with suppliers. Their goal is not just to achieve individual targets but to collectively halve emissions before 2030 and attain net-zero emissions by 2050. Through proactive measures and collaboration, they actively contribute to the reduction of greenhouse gas emissions. By setting an example, these leaders aspire to inspire others within and beyond their networks to join the cause, fostering a collective commitment to combat climate change and strive for a more sustainable future

This is special 2 part edition on ongoing COP28 Session in the UAE. We take up 2 core topics on why climate negotiations started and how will they shape the world and role of supply chain in everything sustainable