Governments must slash emissions further and faster, and keep every climate promise they have made for the planet to be able to return to 1.5C of warming by the end of the century after an inevitable overshoot, a group of prominent climate scientists has said.

In a flagship new report sketching out a way not to lose the most ambitious Paris Agreement goal, the scientists said that global temperatures need to peak at no higher than 1.8C above pre-industrial levels to give the world “a fighting chance” to reverse course. They added that plans to suck carbon dioxide out of the atmosphere can only play a limited role in this effort and cannot substitute for emissions cuts.

A return to the 1.5C warming limit will only be reached in an optimistic scenario that sees governments turn their full national climate plans – known as NDCs – into reality and meet their additional, more ambitious targets to reach net zero emissions, said the report published by the UN Environment Programme (UNEP).

Actual government policy is far off that track. Current measures to cut emissions that are funded and in force put the world on course for around 2.8C of warming by 2100, UNEP has previously found.

Joeri Rogelj, professor of climate science and policy at Imperial College London and one of the report’s authors, said it is necessary to keep the temperature peak as low as possible as there are limits to how fast the world can reverse global warming.

That is because the scale of carbon dioxide removal (CDR) interventions that can be implemented sustainably and in a just way will otherwise not be sufficient and some measures, such as tree-planting or forest management, will be less effective at higher temperatures, he added. 

Commenting on the report, UN Secretary-General António Guterres called for the 1.5C overshoot to be “as small and short as possible”. This, he added, “demands an overshoot of ambition”, involving accelerating the phaseout of fossil fuels and pursuing the renewables revolution, slashing methane pollution, and protecting land, forest and oceans.

“Governments must over-deliver on national climate plans, net-zero commitments, and beyond,” he urged in a video message. “The fight for 1.5 degrees is the fight for humanity.”

Overshoot, peak and decline

The report comes out nearly a year after the UN conceded for the first time that it is inevitable that global warming will exceed 1.5C temporarily and the world should focus on making that overshoot as small and short as possible.

UNEP’s Executive Director Inger Andersen told journalists that 1.5C remains the key goal, but “we now need a different approach from above”, while stepping up efforts to adapt to a warming world.

“A return to 1.5C is not assured,” she added. “But limiting the magnitude, duration and consequences of overshoot, while preserving the possibility of bringing temperatures back down, is the best remaining option to protect vulnerable people, reduce losses and secure a livable future for all.”

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Scientists warn in the report that warming above 1.5C should not be seen as safe or acceptable. Climate risks above that threshold intensify with every additional fraction of a degree of warming, they said. The report paints a grim picture of expected climate impacts: glaciers could lose more than a quarter of their remaining mass by 2100 and global food production could fall by as much as 14% by 2050 without effective adaptation.

Some small island developing states and low-lying coastal cities could be partially or completely submerged, while damaged ecosystems could further accelerate climate change.

“This report is a ‘fork in the road’ moment for the planet,” said Surangel Whipps, Jr., president of the Pacific island nation of Palau. “It is a further glimpse into a perilous future that has already arrived. To continue to have a fighting chance, calls for greater ambition are no longer enough – we need to see an urgent and unprecedented increase in political will and investment in a climate-safe future.”

Cut emissions first, remove carbon after

The authors call for a three-phase approach to bringing temperatures back down: an “immediate response” of deep and rapid emissions cuts and urgent protection for the most vulnerable as warming approaches and passes 1.5C; a “coping and containment” phase focused on reaching net-zero emissions and building resilience as temperatures peak; and a “long-term resilience” phase of net-negative emissions through carbon dioxide removal (CDR) and lasting adaptation as temperatures eventually decline.

Richard Betts, who leads climate impact research at the UK Met Office, said CDR is not a “get-out-of-jail-free card” and should only be additional to emission reductions that need to be achieved with “even more urgency than before”.

Critics of CDR have long pointed to the technology’s record of overpromising and underdelivering, and warn it has been exploited by the fossil fuel industry and some oil-producing states to try to delay the clean energy transition.

Not everyone was fully convinced by the UNEP overshoot report. Veteran climate scientist Bill Hare from Climate Analytics said it “does a good job of describing the hole we’ve dug ourselves into” but “a poor job of showing us that there is a way out”. He argued that its thin treatment of the need for a fossil fuel phase-out and ambitious mitigation pathways to cut emissions risk “turning it into a call to apathy rather than a call to arms”.

“Host of challenges” with CDR

Debra Roberts, honorary professor at the University of KwaZulu-Natal in South Africa, told journalists that limiting global warming to around 1.8C is needed to give the world “a realistic and fighting chance” of returning to the 1.5C limit because of the “questionable” feasibility of interventions above that threshold.

CDR comes with “a whole host of challenges”, she added, including the impacts on food and water security of rolling out large-scale programmes and the unanswered questions of whether newer technologies will work at scale and who will foot the bill.

“It’s going to happen in a very, very complex decision-making space where the risks and impacts are dramatically becoming more complex and interrelated,” she said. “That’s why the pressure there is keep those emissions as low as possible because they give us the greatest fighting chance of the return to 1.5C in a more equitable and just way.”

The post UN sets out narrow path back to 1.5C warming after inevitable overshoot appeared first on Climate Home News.

UN sets out narrow path back to 1.5C warming after inevitable overshoot

Laurence Tubiana is CEO of the European Climate Foundation and was formerly France’s Climate Change Ambassador and Special Representative for COP21 in Paris.

The UN has released a report this week confirming what many people have feared: the world is going to pass 1.5C of warming.

At current emissions, the remaining carbon budget will be exhausted within roughly three years. We are heading into “exceedance” of the 1.5C threshold: a sustained breach of the Paris Agreement’s primary temperature goal before any possible return below it.

1.5C is the line we should not have crossed – and, once we cross it, the line we must quickly get back below, on what the UN Environment Programme calls an “overshoot, peak and decline pathway”.

Of course, climate risk is a spectrum: 1.4C is not safe, and 1.5C is not a sudden cliff edge. But the further the world moves beyond that level, the harder it becomes for communities and economies to adapt, and the greater the risk of more abrupt or systemic changes.

The importance of 1.5C

Some will argue that exceeding 1.5C means the Paris Agreement has failed, and that it is no longer a useful threshold. I disagree.

Before Paris, the world was heading for roughly 3.5C to 4C of warming. The UN now estimates that warming will reach a lower level of around 2.6C by 2100, due to policies implemented since Paris. That is still far too dangerous, but it is not the same world we were facing in 2015.

When we negotiated the Paris Agreement, 1.5C was not an arbitrary number. It was fought for by small island states and other climate-vulnerable countries because it represented a red line for their survival. Since then, we have witnessed the stark impacts of global temperature rises even in countries that did not consider themselves vulnerable, as seen with the devastating heatwaves in Europe this summer.

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The International Court of Justice underlined this in an advisory opinion, endorsed overwhelmingly by the UN General Assembly earlier this year, recognising 1.5C as the primary temperature threshold under the Paris Agreement and affirming that states must align their commitments with it. Overshoot does not move the goalposts. 1.5C remains the benchmark we must work to return to.

Lasting consequences of overshoot

But even as we fight to get back below 1.5C as quickly as possible, we now have to reckon honestly with what overshoot means. We are entering a period for which our societies, economies and institutions are not prepared. Even if overshoot itself is temporary, many of its consequences will not be. The longer it lasts, and the higher temperatures rise, the greater the lasting damage. We therefore need to limit its duration and magnitude.

The longer warming remains above 1.5C, the greater the risk of crossing tipping points in major Earth systems such as ice sheets, the Atlantic Meridional Overturning Circulation, permafrost and tropical forests. Crossing them can trigger self-reinforcing changes that may prove irreversible even if temperatures later fall. We need to understand and monitor these systems more than ever. That requires sustained investment in climate science – just as funding is being cut in many places.

An overshoot pathway will also strain human systems. When a flood destroys a home, the damage is not undone because global temperatures later fall. Crop failures, missed schooling, debt and displacement can have lasting effects. Farms, cities, healthcare systems and insurance markets will all have to cope with risks they were not designed for, and risk facing “tipping points” of their own, such as financial panic when markets suddenly reprice risks they had underestimated. Infrastructure built today will stand for decades, so we need to design and plan for the climate risks it will actually face.

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Our priority must be to transition away from fossil fuels and rapidly cut emissions, including short-lived climate pollutants like methane. It traps around 80 times more heat than carbon dioxide over a 20-year period, and cutting it sharply can act as an emergency brake on near-term warming. Much of the methane from fossil fuel operations can be cut with existing technologies.

We will also need sustainable carbon dioxide removal, although its role will be limited: trying to use it as a substitute for emissions cuts would be prohibitively expensive at scale.

The radical options

The major risks of overshoot have led to proposals to explore active intervention in the climate system itself. Solar radiation modification (SRM) is the best-known example: reflecting a small share of sunlight back into space to reduce warming. Other proposals would target different parts of the climate and Earth systems, such as trying to stabilise glaciers.

These responses would bring us into further uncharted territory across Earth systems and nature, diplomacy and governance, technology and societies.

Such ideas are born of genuine concern about the major risks facing vulnerable countries and communities as temperatures rise. But even under the most favourable assumptions, these are tactics for managing some of the symptoms of overshoot, not a strategy for addressing its causes. Greenhouse gases would keep accumulating, oceans would keep acidifying, and many of the social and economic impacts of overshoot would remain.

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The more we learn about the complexity of the climate and Earth systems we are disrupting and how much uncertainty there already is, the clearer it becomes that full control is likely an illusion, and new interventions bring new complex risks. SRM, for example, could change regional climates, such as rainfall patterns or agricultural production, in ways that benefit some regions and harm others, with knock-on geopolitical risks.

Governance and research needed

None of this is an argument against research into these technologies. On the contrary, the risks they’re responding to are so extreme that we must explore all the options we might have. But we need to understand the potential effects and capabilities much better and from many more angles, including the political and social implications. Serious global governance is particularly urgent, alongside transparent research that is open to scrutiny.

But the fundamental elements of a strategy to navigate overshoot are already understood. The priority is still to rapidly cut greenhouse gas emissions to limit peak warming, protect people against the warming already locked in, and ensure technological innovation aligns with the public interest.

Overshoot is not just an engineering challenge. We need a full-scale response across societies, economies and political systems to prepare to navigate a more uncertain climate.

The post Keeping to 1.5C of warming is no longer possible – but we must still limit the overshoot appeared first on Climate Home News.

Keeping to 1.5C of warming is no longer possible – but we must still limit the overshoot

This week our powerful Pacific team is in Palau for the Pacific Islands Forum Leaders Meeting. This is a major moment in our campaigns for Pacific climate justice and to stop deep sea mining. So what’s it all about, what can we expect over the coming days, and why is this year’s meeting in particular so important? Read on to find out!

_{*Pawa is Melanesian word meaning collective power.}

Meet Moemoana Schwenke, our Pacific Climate Campaigner

“When you love something deeply, you do everything you can to protect it.”

What is the Pacific Islands Forum (PIF)?

The Pacific Islands Forum, or ‘PIF’, is our region’s most important political organisation. It is where countries of the Pacific — including Australia and New Zealand — come together to collaborate on shared challenges and to set collective goals.

The PIF Leaders Meeting is an annual weeklong event that includes a dedicated meeting of the Pacific’s small island developing states (PSIDS), many special side events organised by Pacific civil society, the leaders’ meeting itself, and more. At the end of the week, leaders issue a Forum Communiqué, capturing what they have agreed on, their shared priorities and the actions they will take together.

This year’s meeting is being held in the beautiful northern Pacific nation of Palau, the same place our Pacific team gathered back in January to plan for the year.

What’s at stake this year?

Climate change has dominated the PIF for decades. Pacific leaders have been crystal clear it is their number one priority, and the annual gathering is the moment they can exert maximum pressure on Australia over its fossil fuel record.

The voyage to COP31

This year’s meeting comes less than three months before COP31, where Australia will take on the role of President of Negotiations — a role it has committed to undertaking in partnership with the Pacific — and less than a month before the ‘Pacific Pre-COP’, to be held in Fiji and Tuvalu.

Following a fraught round of mid-year negotiations in Bonn, PIF leaders will need to set out a clear vision and priorities for COP31. These include accelerating a just global transition away from fossil fuels, defending science as the foundation of international climate cooperation, and increasing the availability and accessibility of finance for renewable energy and climate adaptation.

Accountability for Australian fossil fuel exports

Since the last PIF Leaders Meeting, Australia has signed the Belém Declaration on the Transition Away from Fossil Fuels. The declaration reaffirmed the legally binding commitment to help limit global warming to 1.5°C and recognised that this is incompatible with new fossil fuel production. Yet, Australia has continued to approve new coal and gas projects, including at least five since the last PIF Leaders Meeting.

What is Greenpeace doing?

We’re going big this year, taking six members of our team to Palau to support Pacific leaders to hold the line, hold Australia accountable, and show the world what’s at stake. We’ll lobby leaders, hold press conferences, share our messages with the world, and support our incredible local partners in Palau.

How can you get involved?

PIF is the first in a drumbeat of major moments where we’ll be carrying the voices of the Pacific to the world. Come October we’ll be voyaging to Fiji on our ship Oceania for the Pacific Pre-COP, and in November we’ll be off to Antalya for the world’s climate negotiations (COP31).

Learn more about the Pacific way to a fossil fuel free future by checking out our report and exhibition.

Follow our journey, and check back here for more ways to join the movement for climate justice. Together we have the pawa!

Pawa in Palau