By Mark Watts, Executive Director, C40 Cities


The science is now clear – even 2°C of global warming would be highly dangerous to humanity’s future. Thanks to today’s Intergovernmental Panel on Climate Change ‘Special Report on Global Warming of 1.5 °C ’,  leaders in government, business and civil society now know that they must reset their goals to limit global average temperature rise to no more than 1.5°C, a commitment already made by many C40 mayors. Moving quickly to eliminate the use of fossil fuels will accelerate improvements in living standards and enable sustained economic development, but continuing to delay is piling up risk.


Crucially, the Intergovernmental Panel’s report concludes that it is still technically possible that global temperature rise can be kept to within 1.5 degrees above pre-industrial averages, but “limiting global warming to 1.5°C would require rapid and far-reaching systems transitions occurring during the coming one to two decades, in energy, land, urban, and industrial systems.”


That conclusion resonates with all of the research that C40 has undertaken in recent years and matches the scale of ambition and urgency that we are now witnessing in the great cities of the world. Since December 2015 it has been a condition of membership of C40 that by the end of 2020 each of our 96 cities will have published and be delivering a detailed plan for how they will stay within a carbon budget consistent with keeping global temperature rise below 1.5 degrees.


Seven cities have now published climate action plans  specifically designed to deliver on a goal of constraining global average temperature rise below 1.5 degrees, starting with New York and followed by  Barcelona, Copenhagen, London, Oslo, Paris & Stockholm, with a further 65 already committed to do so. This means there are tools readily available for cities and potentially other levels of government to use when creating a climate action plan, including our own C40 Climate Action Planning Framework and our report Cities leading the way, which contains specific examples and lessons for policy makers, drawn from these seven cities.


C40 mayors are motivated both by the tremendous opportunities from low carbon development, but also an increasing recognition of the risks. As the IPCC report soberly analyses, the impact of every half degree of additional warming will be profound. Coral reefs, the engines of marine life, are projected to decline by 99% at 2ºC warming, compared with an already awful 70-90% at 1.5 degrees. “Limiting global warming to 1.5ºC, compared to 2ºC” the report finds, “could reduce the number of people both exposed to climate-related risks and susceptible to poverty by up to several hundred million.”


That chimes with C40’s recent research, The Future We Don’t Want, which revealed that uncontrolled global temperature rise could result in billions of people living in thousands of cities around the world being exposed to extreme high temperatures, coastal flooding, blackouts, droughts and food shortages.


Yet watching and listening to the response to the report across the global media today I am getting increasingly annoyed hearing journalists ask politicians “but is it feasible to keep global warming below 1.5 degrees?”. This seems to me to be exactly the wrong question to pose. Instead our leaders should be confronted with the enquiry that if constraining global warming below 1.5 ºC is not "feasible", then what are the "realistic" plans for humanity thriving in a hothouse Earth, after we have destroyed the eco-system services we need to survive?


Media questions mimic the lines being taken by those with most to lose from anything that disrupts the fossil-fuel-based, high carbon economy. In a particularly breath-taking act of deception, relics of the fossil fuel age appear to have converted from climate deniers to climate fatalists almost overnight. The sheer weight of scientific evidence has rendered the argument that ‘human activity is not causing climate change’ absurd and so instead they claim that dangerous climate change is now inevitable and it is too expensive (“unrealistic”) do anything about it. What these, entirely contradictory, arguments have in common is they justify inaction and protect the status quo.


The “reality” is that the strong messages of hope associated with climate science are all associated with the multiple benefits that will accrue if we eliminate environmental pollution and start living in concert with the rest of the natural world. 


Indeed, the reason that we are so focused on inclusive climate action at C40 – ensuring that the huge investment in shifting to a clean future benefits every citizen – is because climate change is so unfair, clobbering hardest those who did the least to cause it. Cutting emissions, on the other hand, is an opportunity to create societies that are both less polluted and more equitable.


Those who still want to cling to the old, failing world of polluting our way to industrial progress try to paint climate science as utopian. But most of the findings that climate scientists want us to understand in this IPCC report are consistent with conversations I have every week with mayors and city leaders around the world.


A sustainable future will be powered by renewable energy and the IPCC authors confirm that 49–67% of primary energy should come from renewable sources by 2050, and just 1-7% powered by coal. Actually, leading mayors are already working on the basis of stronger targets of zero fossil fuel energy by mid-century at the latest.


Emissions must be cut sharply from the buildings and transport sectors, particularly important in cities. That’s why a few weeks ago at the Global Climate Action Summit we organized for tens of mayors to start introducing regulations that require buildings to be zero carbon by 2030 at the latest, as well as committing to only purchase zero carbon buses from 2025 at the latest.


Limiting global warming to 1.5°C cannot be achieved by incremental steps or technological magic bullets. The changes in personal behavior, patterns of consumption and how our economies function will be profound. More so than any previous IPCC analysis, the message of the Special Report on Global Warming of 1.5 °C ’,is that every single citizen has a part to play in securing a climate safe future. That fits with C40’s analysis that mayors have an important role to play in making it easy for environmentally responsible products to get to market, particularly in the food sector, where citizens need to be given the choice to eat sustainably.


The IPCC report is so powerful, precisely because it makes clear that we are not too late.  Now is the moment to transform our economies; embrace low carbon technologies that will create millions of good, local green jobs; provide cheap abundant energy for all, whilst also cleaning the air that we all breathe.


It is also a moment to reflect on the fact that it was the most vulnerable countries in the United Nations that forced the inclusion of an aspirational 1.5 degree goal into the Paris climate agreement. Now we have definitive scientific evidence that they were right, we all ought to ensure that the voices of the least well-off are more loudly heard going forward, so that we can not only frame the problem correctly, but also back solutions that will deliver the most universal benefit.

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