Claps echoed when the historic climate goal was agreed upon in Paris. Now it is being broken.

The ambitious goal in the Paris Agreement to limit global warming to 1.5 °C is dead.

It may be that at some point we will again be able to lower the temperature by removing CO2 from the atmosphere, but the fact is that we will exceed the target. Probably as early as the end of this decade.

How much and how long the temperature target is exceeded depends on us.

This is the conclusion of the UN in a new report, 'Limiting Overshoot', from its environmental agency UNEP, which advises to make the overshoot of the target as minimal as possible and work to get below 1.5 °C again.

"This summer's scorching heat, violent wildfires, and deadly floods are a warning of what awaits us. We must ensure that the overshoot of 1.5 °C is as small and short-lived as possible. This requires us to set our ambitions even higher," says UN Secretary-General António Guterres in a press release.

Warming has almost reached 1.4 °C, and from an agricultural perspective, the report is very bad news: Climate change will lead to significant productivity losses and threaten food security as well as the livelihoods of billions of people. The report refers to forecasts indicating that global food production could potentially fall by up to 14 percent by 2050 if production is not climate-adapted.

One of the measures to limit warming is to curb methane emissions. So far, the focus has primarily been on methane from fossil fuels, while agriculture and waste sectors have been more or less exempt from climate measures, and when the low-hanging fruit in the fossil industry has been picked, it is time to ramp up efforts in these sectors, the authors write. They also point out that there are significant reductions to be gained if we change our dietary habits and eat less meat and more greens.

The world has changed

If it ever succeeds in the future to lower the temperature by stopping our emissions and removing greenhouse gases from the atmosphere using technology and reforestation, we will not avoid losses and permanently altered conditions for many people, warns the report.

At the same time, we cannot avoid climate adaptation to mitigate the most extreme weather events.

"There are no positive outcomes if we stay above 1.5 °C. Across the world, extreme heatwaves already show that climate effects will occur faster, hit harder, and last longer – which will cost more lives and cause greater disruptions," says Inger Andersen, Director-General of UNEP.

The most optimistic scenario shows that we are heading towards a warming of 1.8 °C relative to pre-industrial levels, while most other scenarios indicate an even higher temperature rise.

Irreversible damages

The report warns that the risk of triggering irreversible tipping points in the climate system increases as temperatures rise higher and stay there. Large ice caps risk becoming unstable, the Amazon rainforest could degrade, and the Atlantic Meridional Overturning Circulation (AMOC), which transports heat to Europe, could be disrupted.

"Despite decades of scientific warnings and the growing scientific evidence, the resulting climate targets have not led to sufficiently rapid emission reductions," says Debra Roberts, former co-chair of Working Group II of the UN Climate Panel, IPCC, to Health Policy Watch.

With current policies, the world is on track for a temperature increase of 2.6 °C by the end of this century.

"All our pathways forward are pathways that lead to overshoot. We are clearly entering uncharted territory," says Debra Roberts.

Rapid, significant reductions

The report is not written as a death sentence. UNEP emphasizes that overshoot is not an argument to give up, but to act faster: Every tenth of a degree and every year of less overshoot saves lives and limits natural and economic losses.

The authors outline a three-phase process. First, deep emission reductions with particular emphasis on methane, which acts quickly on temperature, combined with urgent adaptation for the most vulnerable people.

The next phase aims to reach net-zero emissions so that greenhouse gases no longer accumulate in the atmosphere. This should be achieved, among other things, by phasing out fossil fuels and restoring ecosystems that can draw CO2 out of the atmosphere and store carbon.

In the third phase, there is a need to remove more CO2 from the atmosphere than we emit, so that temperatures can fall again.

"The climate system functions like a huge kettle. By reducing emissions, the flame is turned down, and when net-zero is reached, we stop adding heat. But the heat already accumulated does not disappear. It takes decades – or much longer – for the oceans, ice caps, and ecosystems to respond, and it requires more than just turning off the gas to make temperatures fall again. This makes the future very difficult to predict," explains Mirey Atallah, head of UNEP’s Adaptation and Resilience Department.

For agriculture, the levers are mainly in the first phase. Methane from livestock and waste is the next major focus area because methane from fossil sources can be removed relatively cheaply before 2050.

So far, agriculture and waste sectors have been more or less exempt from climate measures, so once the low-hanging fruit in the fossil industry has been picked, it is time to ramp up efforts in these sectors, the authors write. They also point out that there are significant reductions to be gained if we change our dietary habits and eat less meat and more greens.

The report highlights new technologies for livestock methane and that dietary changes alone can cut 0.7-8.0 gigatons of CO₂-equivalent emissions annually from the food system's emissions.