Limiting global warming to 1.5°C would save billions

Limiting global warming to 1.5°C would save billions


Limiting global warming to 1.5°C would save billions from the dangerously hot climate, but not only that.  It could bring improvements to life with cleaner air and improved water and soil quality.  


The image above is on the many effects of dangerously high temperatures, including reduced crop yield. Credit Pablo Tosco / Oxfam International

Limiting global warming to 1.5°C would save billions from dangerously hot climate


Current climate policies will leave more than a fifth of humanity exposed to dangerously hot temperatures by 2100, new research suggests.

Despite the Paris Agreement pledge to keep global warming well below 2°C (compared to pre-industrial levels), current policies are projected to result in 2.7°C warming by the end of the century.

The new study, led by researchers at the Global Systems Institute, University of Exeter, associated with the Earth Commission, and Nanjing University, assessed what this would mean for the number of people living outside the “climate niche” in which our species has thrived.

It says about 60 million people are already exposed to dangerous heat (average temperature of 29°C or higher).

And two billion – 22% of the projected end-of-century population – would be exposed to this at 2.7°C of global warming.

The paper highlights the “huge potential” for decisive climate policy to limit the human costs and inequities of climate change.

Limiting warming to 1.5°C would leave 5% exposed – saving a sixth of humanity from dangerous heat compared to 2.7°C of warming.

The study also finds that the lifetime emissions of 3.5 average global citizens today – or just 1.2 US citizens – expose one future person to dangerous heat. This highlights the inequity of climate crisis, as these future heat-exposed people will live in places where emissions today are around half of the global average.

In “worst-case scenarios” of 3.6°C or even 4.4°C global warming, half of the world’s population could be left outside the climate niche, posing what the researchers call an “existential risk”.

“The costs of global warming are often expressed in financial terms, but our study highlights the phenomenal human cost of failing to tackle the climate emergency,” said Professor Tim Lenton, director of the Global Systems Institute at the University of Exeter.

“For every 0.1°C of warming above present levels, about 140 million more people will be exposed to dangerous heat.

“This reveals both the scale of the problem and the importance of decisive action to reduce carbon emissions.

“Limiting global warming to 1.5°C rather than 2.7°C would mean five times fewer people in 2100 being exposed to dangerous heat.”

Defining the niche

Human population density has historically peaked in places with an average temperature of about 13°C, with a secondary peak at about 27°C (monsoon climates, especially in South Asia).

Density of crops and livestock follow similar patterns, and wealth (measured by GDP) peaks at about 13°C.

Mortality increases at both higher and lower temperatures, supporting the idea of a human “niche”.

Although less than 1% of humanity currently live in places of dangerous heat exposure, the study shows climate change has already put 9% of the global population (more than 600 million people) outside the niche.

“Most of these people lived near the cooler 13°C peak of the niche and are now in the ‘middle ground’ between the two peaks. While not dangerously hot, these conditions tend to be much drier and have not historically supported dense human populations,” said Professor Chi Xu, of Nanjing University.

“Meanwhile, the vast majority of people set to be left outside the niche due to future warming will be exposed to dangerous heat.

“Such high temperatures have been linked to issues including increased mortality, decreased labour productivity, decreased cognitive performance, impaired learning, adverse pregnancy outcomes, decreased crop yield, increased conflict and infectious disease spread.”

While some cooler places may become more habitable due to climate change, population growth is projected to be highest in places at risk of dangerous heat, especially India and Nigeria.

The study also found:

  • Exposure to dangerous heat starts to increase dramatically at 1.2°C (just above current global warming) and increases by about 140 million for every 0.1°C of further warming.
  • Assuming a future population of 9.5 billion people, India would have the greatest population exposed at 2.7°C global warming – more than 600 million. At 1.5°C, this figure would be far lower, at about 90 million.
  • Nigeria would have the second-largest heat-exposed population at 2.7°C global warming, more than 300 million. At 1.5°C warming this would be less than 40 million.
  • India and Nigeria already show “hotspots” of dangerous temperatures.
  • At 2.7°C, almost 100% of some countries including Burkina Faso and Mali will be dangerously hot for humans. Brazil would have the largest land area exposed to dangerous heat, despite almost no area being exposed at 1.5 °C. Australia and India would also experience massive increases in area exposed.

The research team – which included the Potsdam Institute for Climate Impact Research, the International Institute for Applied Systems Analysis, and the Universities of Washington, North Carolina State, Aarhus and Wageningen – stress that the worst of these impacts can be avoided by rapid action to cut greenhouse gas emissions.

Speaking about the conception of their idea, Professor Marten Scheffer, of Wageningen University, said: “We were triggered by the fact that the economic costs of carbon emissions hardly reflect the impact on human wellbeing.

“Our calculations now help bridging this gap and should stimulate asking new, unorthodox questions about justice.”

Ashish Ghadiali, of Exeter’s Global Systems Institute, said: “These new findings from the leading edge of Earth systems science underline the profoundly racialised nature of projected climate impacts and should inspire a policy sea-change in thinking around the urgency of decarbonisation efforts as well as in the value of massively up-shifting global investment into the frontlines of climate vulnerability.”

The research was funded by the Open Society Foundations and the paper is also an output of the Earth Commission – convened by Future Earth, the Earth Commission is the scientific cornerstone of the Global Commons Alliance.

Wendy Broadgate, Executive Director of the Earth Commission at Future Earth, said: “We are already seeing effects of dangerous heat levels on people in different parts of the world today. This will only accelerate unless we take immediate and decisive action to reduce greenhouse gas emissions.”

Work on climate solutions by the Global Systems Institute at the University of Exeter has identified “positive tipping points” to accelerate action, including a recent report that highlighted three “super-leverage points” that could trigger a cascade of decarbonisation.

The paper, published in the journal Nature Sustainability, is entitled: “Quantifying the Human Cost of Global Warming.”

Read more on University of Exeter


We are about to break the 1.5°C limit


We are about to break the 1.5°C limit, but could we get energy from this untapped source?

18 May 2023

Energy-hungry data centres already match the aviation industry in terms of their contribution to global warming. Could they be adapted to heat other buildings as standard, wonders Kunle Barker

An article in the Economist last year entitled, ‘Say goodbye to 1.5°C’ made for depressing reading. It claimed we had already lost one of the critical battles in the climate war. The article suggested that we stood little chance of restricting the world’s post-industrial temperature rise to 1.5°C. The only way I could process this news was to ignore it. I convinced myself we were still on target and that the messaging was helpful as it would chivvy us all into focusing on hitting the 1.5°C target.

Sadly, the UN Climate Report released in March confirmed the Economist s conclusion. And this week, scientists have said the 1.5°C threshold is likely to be broken over the next few years.

Even for an eternal optimist like myself, this is worrying and disappointing. After COP26, as I drove back to London in my EV, I felt hopeful and sure that the world would do what was needed to save the planet. Little did I know, as I triumphantly plugged my EV into a supercharger at Rugby services, it was already too late to save the 1.5-degree target.

I’ve written many columns about the critical role the built environment sector could play in averting a climate disaster. To a large extent, as an industry, our intent is clear: we question, campaign, and push each other to do better. However, something sinister may lurk underneath the surface of our hubris.

A recent BBC story about a swimming pool in Exeter that used a data centre as its heat source grabbed my attention. The story reminded me of a train journey I shared with fellow Manser Medal judge, Joe Jack Williams, in which he described using data centres as heat sources in heritage assets. The use of waste heat fascinated me, but the wider application struck me only while reading this BBC article. Could data centres be used as heat sources for homes, schools even entire developments?

Using excess heat is by no means a new idea. The Churchill Gardens estate, which started construction in 1946, used excess heat from Battersea Power Station. However, my research into the topic revealed a surprising fact about the impact on our environment of data centres: They are ‘sleeping giants’ when it comes to CO2 emissions.

Today, data centres account for 2 per cent of the world’s carbon footprint, similar to the aeronautical industry and only 1.6% less than the petrochemical industry. This is worrying enough, but there are predictions that by 2030 data centres will be responsible for more carbon emissions than both those industries combined.

When this sleeping giant awakens, our industry will shoulder the blame because we will have designed and built the structures these carbon goliaths inhabit.

An obvious solution would be to argue for restricting the growth of the data centre industry, but I believe it’s too late for this. In many ways, it has already happened. Our reliance on online payments, AI, cloud storage and so on is already integrated into our society’s fabric, and it is too late to go back.

But there could be a solution. Around 70 per cent of data centres’ energy is used for cooling, and this is set to climb to 80 per cent as machines used for AI and Blockchain operate more efficiently at lower temperatures. Data centres are usually designed on a large scale but perhaps they could be used to heat individual buildings if they were made smaller and supply and demand of this heat were efficiently balanced.

Designing smaller data centres would allow their integration into large-scale developments. Imagine a mini data centre located in each plot of a development, using the excess energy to heat space and water. This would represent a significant carbon saving for all involved.

This concept is not without its challenges. Although data centres produce heat constantly, it’s not very high quality, and even with the best form of heat exchange, you will struggle to get 30 degrees out of the system. But we as an industry must try, must ask ‘what if?’ and must push for rapid innovation. Unlike the adage, ‘the diet begins tomorrow’, it seems we may have already run out of tomorrows.

Kunle Barker is a property expert, journalist and broadcaster



Bracing for climate change-fuelled summer of drought


A typical image above of what Bracing for climate change-fuelled summer of drought is about.

It is about Pistachio trees in a field affected by the prolonged drought in Ronda, southern Spain May 11, 2023. REUTERS/Jon Nazca/File Photo

Southern Europe braces for climate change-fuelled summer of drought


  • 22% of Europe under drought warning
  • Spain worst-hit, already in severe drought
  • Some farmers expect worst harvest for decades
  • Climate change fuelling drought conditions


BRUSSELS, May 17 (Reuters) – Southern Europe is bracing for a summer of ferocious drought, with some regions already suffering water shortages and farmers expecting their worst yields in decades.

As climate change makes the region hotter and drier, years of consecutive drought have depleted groundwater reserves. Soils have become bone dry in Spain, southern France and Italy. Low river and reservoir levels are threatening this summer’s hydropower production.

With temperatures climbing into summertime, scientists warn Europe is on track for another brutal summer, after suffering its hottest on record last year – which fuelled a drought European Union researchers said was the worst in at least 500 years.

So far this year, the situation is most severe in Spain.

“The situation of drought is going to worsen this summer,” said Jorge Olcina, professor of geographic analysis at the University of Alicante, Spain.

There’s little chance at this point of rainfall resolving the underlying drought, either. “At this time of the year, the only thing we can have are punctual and local storms, which are not going to solve the rainfall deficit,” Olcina said.

Seeking emergency EU assistance, Spain’s Agriculture Minister Luis Planas warned that “the situation resulting from this drought is of such magnitude that its consequences cannot be tackled with national funds alone,” according to an April 24 letter sent to the European Commission (EC) and seen by Reuters.

A vegetable patch is affected by the prolonged drought, in Ronda, southern Spain May 11, 2023. REUTERS/Jon Nazca/File Photo


Southern Europe is not alone in suffering severe water shortages this year. The Horn of Africa is enduring its worst drought in decades, while a historic drought in Argentina has hammered soy and corn crops.

More frequent and severe drought in the Mediterranean region – where the average temperature is now 1.5C higher than 150 years ago – is in line with how scientists have forecast climate change will impact the region.

“In terms of the climate change signal, it very much fits with what we’re expecting,” said Hayley Fowler, Professor of Climate Change Impacts at Newcastle University.

Despite these long-held forecasts, preparation is lagging. Many farming regions have yet to adopt water-saving methods like precision irrigation or switch to more drought-hardy crops, such as sunflowers.

“Governments are late. Companies are late,” said Robert Vautard, a climate scientist and director of France’s Pierre-Simon Laplace Institute. “Some companies are not even thinking of changing the model of their consumption, they are just trying to find some miraculous technologies that would bring water.”

France is emerging from its driest winter since 1959, with drought “crisis” alerts already activated in four departmental prefects, restricting non-priority water withdrawals – including for agriculture, according to government website Propluvia.

Portugal, too, is experiencing an early arrival of drought. Some 90% of the mainland is suffering from drought, with severe drought affecting one-fifth of the country – nearly five times the area reported a year earlier.

In Spain, which saw less than half its average rainfall through April this year, thousands of people are relying on truck deliveries for drinking water, while regions including Catalonia have imposed water restrictions.

Some farmers have already reported crop losses as high as 80%, with cereals and oilseeds among those affected, farming groups have said.

“This is the worst loss of harvest for decades,” Pekka Pesonen, who heads the European farming group Copa-Cogeca, said of Spain. “It’s worse than last year’s situation.”

Spain is responsible for half of the EU’s production of olives and one third of its fruit, according to the Commission.

With its reservoirs at on average 50% of capacity, the country last week earmarked more than 2 billion euros ($2.20 billion) in emergency response funding. It is still awaiting a reply from the Commission on its request for a 450-million-euro crisis fund to be mobilized from the bloc’s farming subsidy budget.

The Commission said it was monitoring the situation closely.

“Severe drought in Southern Europe is particularly worrying, not only for the farmers there but also because this can push up already very high consumer prices if the EU production is significantly lower,” Commission spokesperson Miriam Garcia Ferrer said.

Similar struggles are expected in Italy, where up to 80% of the country’s water supply goes toward agriculture. But with this year’s thin mountain snow cover and low soil moisture, Italian farmers are planning to cut back – sowing summer crops across an area 6% smaller than last year’s planting area, according to national data on sowing intentions.

After two years of water scarcity, northern Italy has a 70% deficit in snow water reserves and a 40% deficit of soil moisture, said Luca Brocca, a Director of Research at Italy’s National Research Council.

Such deep shortages set the stage for a repeat of last year’s summer, when Italy suffered its most severe drought in 70 years.

“2022 was really exceptional. And also this year, it seems to be really exceptional,” Brocca said.

($1 = 0.9084 euros)

Reporting by Kate Abnett; editing by Katy Daigle and Sharon Singleton

How is Climate Change Affecting MENA? Local Experts Weigh In


How is Climate Change Affecting MENA? Local Experts Weigh In each, in their respective area but in a similar way throughout the varying specifics of the MENA regions . . .


How is Climate Change Affecting MENA? Local Experts Weigh In

For Earth Day 2023, members of the Agents of Change Youth Fellowship answered this question: What is the biggest environmental or climate change related challenge facing your community today? Their responses reveal a pattern of vulnerability facing the MENA region.

Groundwater depletion in the West Bank

Climate change will affect most sectors of the economy in the Palestinian territories, especially the water sector, which will be among the most affected in terms of water availability and quality. Freshwater resources—surface and groundwater—will become more scarce due to decreasing precipitation rates. This will make it more difficult to replace groundwater during periods of high population growth, coinciding with the intensification of competition for water between Palestinian agriculture, Israeli settlements, and the industrial sector.

“High temperatures and excessive precipitation rates may threaten the quality of drinking water, given the limited treatment facilities.”

Less rainfall will also increase the cost and amount of energy needed to extract water. In addition, high temperatures and excessive precipitation rates may threaten the quality of drinking water, given the limited treatment facilities. Measurements of groundwater levels through a geological survey of some areas of the West Bank have observed that 45% of the sub-aquifers have decreased sharply and significantly, and this has led to the desiccation of 15% of the soils in the areas surrounding the decreasing aquifers.

This exacerbates the water demand crisis, which will have direct effects on the topology of the food network, which constitutes an important resource that supports the Palestinian economy, in addition to the fact that the West Bank is already suffering from a major water crisis. Climate change predictions for the Palestinian territories from high-resolution regional climate models show above-average global warming over this century in the range of 2.12-4.9°C (35.8-40.82°F) according to a realistic emissions scenario.

The impact of climate change on groundwater in the West Bank and the decrease in its quantities have led to a significant increase in the prices of agricultural products, especially those from agriculture that relies extensively on irrigation; 7% of farmers have left their lands due to the high cost of obtaining water.

Financing Climate Action in Egypt

Building climate resilience while coping with near-term crises is crucial, but neither can be achieved without adequate finance. Unfortunately, climate finance is not keeping up with climate change’s escalating impacts. Egypt is among the most susceptible countries to climate change due to its growing population concentrated in the densely populated Nile Delta. Egypt’s carbon emissions increased by 155% between 1990 and 2018, three times more than the global rate of 50%. Additionally, climate change is projected to cost Egypt between 2% and 6% of its GDP by 2060.

In response, the Egyptian government has developed a coherent policy agenda for climate action that is institutionally ahead of many of its MENA peers. The country has made significant strides in climate change mitigation and adaptation strategies, such as doubling its wind energy production, constructing desalination plants and flood control infrastructure, and launching the first green sovereign bond in the MENA region, worth $750 million and offering a 5.25% yield. The country pledged to cut emissions by 25% by 2030 in its revised Nationally Determined Contribution (NDC), which also encompasses various adaptation and mitigation projects. Yet, for these projects to be completed by 2030, $50 billion in financing is required.

“The lack of adequate financial resources remains Egypt’s main obstacle to responding to climate hazards.”

Unfortunately, the Egyptian pound suffered a half-value decline last year, making it the worst-performing currency in 2023. Even though the country receives the most significant proportion of climate finance in the MENA region (28%), the region hosts the least amount of climate finance globally, estimated at $16 billion annually, with financing needs estimated at $186 billion based on countries’ NDCs.

Deferring climate finance investment is not an option. The lack of adequate financial resources remains Egypt’s main obstacle to responding to climate hazards. Collaboration with the private sector, foreign direct investment, and international cooperation will open doors to alternative financial resources for the country’s green transition.

Decreasing Snowpack and Rainfall in Turkey

The most urgent climate-related challenge facing Turkey is elevated drought risk. As part of the Mediterranean Basin, a climate hot spot, Turkey will experience the consequences of climate change earlier and harsher than many other parts of the world, including more severe and prolonged droughts. These drought events typically occur concurrently with three trends: (1) a shrinking snowpack, hence reduced flows in Turkey’s rivers, (2) higher average temperatures, which also escalate extreme heat risk, and (3) less rainfall in southern regions, resulting in a drier climate and aridification.

These droughts can be debilitating for Turkey in several ways. In times of drought, crops need more watering due to less rainfall and hotter weather. Furthermore, elevated extreme heat risks threaten crop health, leading to reduced crop yield at best and complete crop loss at worst. More intense droughts mean more severe wildfires, particularly in the Mediterranean region. Forest vegetation dries up and becomes more flammable due to hotter weather and inadequate rainfall.

Many cities in Turkey are vulnerable since they mainly rely on captured rainfall and river flows to supply water for their residents. During droughts, cities have less water, and their ability to provide water for human consumption is imperiled. Turkey depends heavily on hydropower to meet the country’s electricity demand. But during droughts, hydropower output can decrease dramatically as the water levels in reservoirs drop. This results in more reliance on imported fossil fuels like coal and natural gas to compensate for the loss.

These impacts jeopardize everyone’s welfare in Turkey by endangering food, water, and energy security, as well as posing public health threats and harming Turkey’s precious ecosystems.

These impacts jeopardize everyone’s welfare in Turkey by endangering food, water, and energy security, as well as posing public health threats and harming Turkey’s precious ecosystems. Investing in water conservation and wastewater recycling, boosting funding for maintaining forest health, and implementing tighter groundwater management regulations could be good starting points.

Extreme Temperatures Adds Up in Warming Gulf Countries

The Middle East and the Arab region are already facing rising temperatures almost twice as quickly as the rest of the world, according to a report by the Cyprus Institute’s Climate and Atmosphere Research Center and the Max Planck Institute for Chemistry. The temperature during summer in the already very hot in MENA and will increase more than two times faster than the global average, making it one of the most vulnerable regions in the world to the disastrous consequences of climate change.

In recent years, we have started to see the extreme weather impacts in a much more visible way, adding to the already existing temperature rise. According to the study, what makes the Arab region more susceptible to higher increases in temperatures than some other parts of the world are geographical features such as large expanses of desert and lower ground water levels. Extreme weather conditions such as the deadly flash floods in Fujairah in the UAE, flooding in Qatar, and flash floods in Oman are examples of the impacts affecting the Gulf region.

“When extreme weather and temperature are combined, the consequences are multiplied several fold–making populations in the Arab region more vulnerable.”

When extreme weather and temperature are combined, the consequences are multiplied severalfold–making populations in Arab region more vulnerable. In these challenging times, it is crucial for the world to come together and address the threat of climate change and help countries in the Arab Middle East to adapt. Regardless of the climate change scenario in the latest IPCC AR6 synthesis report, it will become reality soon or later: climate change will result in a significant deterioration of living conditions for people living in the Arab Middle East countries, and consequently, many people may have to leave the region due to rising temperatures.

Khalil Abu Allan is an Agents of Change Youth Fellow, and faculty member at Hebron University, West Bank, in the Department of Applied Geography.

Eslam A. Hassanein is an Agents of Change Youth Fellow, and is an assistant lecturer at the Faculty of Politics and Economics- Beni Suef University- Egypt.

Gokce Sencan is an Agents of Change Youth Fellow, and a climate and water policy researcher based in California.

Neeshad Shafi is an Agents of Change Youth Fellow, and the Co-founder & Executive Director at the Arab Youth Climate Movement Qatar, a first registered youth lead non-profit association in the State of Qatar.

Photo Credit: In Al-Chibayish, Iraq, a Marsh Arab woman collects water in the wetlands of the Central Marshes of southern Iraq, courtesy of John Wreford/

This article was originally published as part of the Viewpoints Series of the Wilson Center’s Middle East Program.



Masking the true scale of action needed to avert Climate Change


Masking the true scale of action needed to avert Climate Change is increasingly obvious to many observers around the world.  Here is Kevin Anderson, University of Manchester with his own perception of the issue.



IPCC’s conservative nature masks true scale of action needed to avert catastrophic climate change


The Intergovernmental Panel on Climate Change’s (IPCC) synthesis report recently landed with an authoritative thump, giving voice to hundreds of scientists endeavouring to understand the unfolding calamity of global heating. What’s changed since the last one in 2014? Well, we’ve dumped an additional third of a trillion tonnes of CO₂ into the atmosphere, primarily from burning fossil fuels. While world leaders promised to cut global emissions, they have presided over a 5% rise.

The new report evokes a mild sense of urgency, calling on governments to mobilise finance to accelerate the uptake of green technology. But its conclusions are far removed from a direct interpretation of the IPCC’s own carbon budgets (the total amount of CO₂ scientists estimate can be put into the atmosphere for a given temperature rise).

The report claims that, to maintain a 50:50 chance of warming not exceeding 1.5°C above pre-industrial levels, CO₂ emissions must be cut to “net-zero” by the “early 2050s”. Yet, updating the IPCC’s estimate of the 1.5°C carbon budget, from 2020 to 2023, and then drawing a straight line down from today’s total emissions to the point where all carbon emissions must cease, and without exceeding this budget, gives a zero CO₂ date of 2040.

If emissions stay at their current levels, we will exhaust the 50% chance of 1.5°C in 9 years. If we begin to immediately cut emissions following the blue line, then to stay within the carbon budget for 50:50 chance of not exceeding 1.5°C we need zero global emissions by 2040. The vertical axis represents how much carbon is emitted each year – note the pandemic-related blip in 2020.
Kevin Anderson / Climate Uncensored, Author provided

A full description of the above chart is available here.

Given it will take a few years to organise the necessary political structures and technical deployment, the date for eliminating all CO₂ emissions to remain within 1.5°C of warming comes closer still, to around the mid-2030s. This is a strikingly different level of urgency to that evoked by the IPCC’s “early 2050s”. Similar smoke and mirrors lie behind the “early 2070s” timeline the IPCC conjures for limiting global heating to 2°C.

IPCC science embeds colonial attitudes

For over two decades, the IPCC’s work on cutting emissions (what experts call “mitigation”) has been dominated by a particular group of modellers who use huge computer models to simulate what may happen to emissions under different assumptions, primarily related to price and technology. I’ve raised concerns before about how this select cadre, almost entirely based in wealthy, high-emitting nations, has undermined the necessary scale of emission reductions.

In 2023, I can no longer tiptoe around the sensibilities of those overseeing this bias. In my view, they have been as damaging to the agenda of cutting emissions as Exxon was in misleading the public about climate science. The IPCC’s mitigation report in 2022 did include a chapter on “demand, services and social aspects” as a repository for alternative voices, but these were reduced to an inaudible whisper in the latest report’s influential summary for policymakers.

The specialist modelling groups (referred to as Integrated Assessment Modelling, or IAMs) have successfully crowded out competing voices, reducing the task of mitigation to price-induced shifts in technology – some of the most important of which, like so-called “negative emissions technologies”, are barely out of the laboratory.

The IPCC offers many “scenarios” of future low-carbon energy systems and how we might get there from here. But as the work of academic Tejal Kanitkar and others has made clear, not only do these scenarios prefer speculative technology tomorrow over deeply challenging policies today (effectively a greenwashed business-as-usual), they also systematically embed colonial attitudes towards “developing nations”.

With few if any exceptions, they maintain current levels of inequality between developed and developing nations, with several scenarios actually increasing the levels of inequality. Granted, many IAM modellers strive to work objectively, but they do so within deeply subjective boundaries established and preserved by those leading such groups.

March 2023’s synthesis report capped eight years of research.
IISD/ENB/Anastasia Rodopoulou

What happened to equity?

If we step outside the rarefied realm of IAM scenarios that leading climate scientist Johan Rockström describes as “academic gymnastics that have nothing to do with reality”, it’s clear that not exceeding 1.5°C or 2°C will require fundamental changes to most facets of modern life.

Starting now, to not exceed 1.5°C of warming requires 11% year-on-year cuts in emissions, falling to nearer 5% for 2°C. However, these global average rates ignore the core concept of equity, central to all UN climate negotiations, which gives “developing country parties” a little longer to decarbonise.

Include equity and most “developed” nations need to reach zero CO₂ emissions between 2030 and 2035, with developing nations following suit up to a decade later. Any delay will shrink these timelines still further.

Most IAM models ignore and often even exacerbate the obscene inequality in energy use and emissions, both within nations and between individuals. As the International Energy Agency recently reported, the top 10% of emitters accounted for nearly half of global CO₂ emissions from energy use in 2021, compared with 0.2% for the bottom 10%. More disturbingly, the greenhouse gas emissions of the top 1% are 1.5 times those of the bottom half of the world’s population.

So where does this leave us? In wealthier nations, any hope of arresting global heating at 1.5 or 2°C demands a technical revolution on the scale of the post-war Marshall Plan. Rather than relying on technologies such as direct air capture of CO₂ to mature in the near future, countries like the UK must rapidly deploy tried-and-tested technologies.

Retrofit housing stock, shift from mass ownership of combustion-engine cars to expanded zero-carbon public transport, electrify industries, build new homes to Passivhaus standard, roll-out a zero-carbon energy supply and, crucially, phase out fossil fuel production.

Three decades of complacency has meant technology on its own cannot now cut emissions fast enough. A second, accompanying phase, must be the rapid reduction of energy and material consumption.

Given deep inequalities, this, and deploying zero-carbon infrastructure, is only possible by re-allocating society’s productive capacity away from enabling the private luxury of a few and austerity for everyone else, and towards wider public prosperity and private sufficiency.

For most people, tackling climate change will bring multiple benefits, from affordable housing to secure employment. But for those few of us who have disproportionately benefited from the status quo, it means a profound reduction in how much energy we use and stuff we accumulate.

The question now is, will we high-consuming few make (voluntarily or by force) the fundamental changes needed for decarbonisation in a timely and organised manner? Or will we fight to maintain our privileges and let the rapidly changing climate do it, chaotically and brutally, for us?

Kevin Anderson, Professor of Energy and Climate Change, University of Manchester