Rising temperatures, natural disasters and irreversible ecosystem degradation are becoming increasingly life-threatening for humans and nature all over the world, top scientists warned in a major new report released Monday by the UN's Intergovernmental Panel on Climate Change.

Efforts made so far to avoid passing a dangerous global threshold have been "insufficient to tackle climate change," but multiple options are still available.

"Mainstreaming effective and equitable climate action will not only reduce losses and damages for nature and people, it will also provide wider benefits," said IPCC Chair Hoesung Lee. "This Synthesis Report underscores the urgency of taking more ambitious action and shows that, if we act now, we can still secure a livable sustainable future for all."

"Today's IPCC report is a how-to guide to defuse the climate time-bomb," said UN Secretary-General Antonio Guterres. "It is a survival guide for humanity. As it shows, the 1.5-degree limit is achievable. But it will take a quantum leap in climate action."

Climate protection measures fall short

The fundamental message of all the IPCC's reports is unequivocal. "Without urgent, effective, and equitable mitigation and adaptation actions, climate change increasingly threatens ecosystems, biodiversity, and the livelihoods, health and well-being of current and future generations," said the report, compiled by 93 authors.

Humanity has drastically altered the planet in just a few centuries, with responsibility for climate change linked to the burning of coal, oil and gas. At no time in the past 2 million years have CO2 concentrations in the Earth's atmosphere been as high as they are today.

The Earth has already warmed by at least 1.1 degrees Celsius (2 degrees Fahrenheit) compared to pre-industrial times in the mid 19th century. In 2015, world leaders agreed after intense negotiations to limit global warming to a common target of 1.5 degrees. So far, no major country is on schedule to meet this goal.

Future scenarios clearly show that climate change can only be halted with a radical transformation of the world's energy system. In addition, the report stressed that measures to adapt to the effects of climate change must already be implemented today. This will save lives and money, when compared with the costs of unchecked climate change on the global economy and society.

However, the window of opportunity to achieve these goals is closing fast, the scientists said. By 2030, the global community needs to nearly halve its emissions from burning coal, oil and gas, or face warming of around 3 degrees Celsius.

Guterres called on world leaders and fossil fuel companies to "massively fast-track climate efforts by every country and every sector and on every time frame." Speaking on Monday, he presented a plan to accelerate net-zero climate deadlines, invest in realistic innovations and deliver climate justice to those experiencing the worst effects of climate change.

World mustn't rely on promise of future tech: IPCC

The Intergovernmental Panel on Climate Change, set up in 1988, is a United Nations body that analyzes the latest climate research. Hundreds of scientists from around the world study the ongoing impacts and future risks posed by the climate crisis, as well as ways to help people mitigate the negative impacts and adapt to a warmer planet.

Europe is increasingly seeing the effects of climate change, as seen after extreme flooding in Germany in 2021. Photo: AFP

These experts collectively evaluate thousands of scientific studies, as well as government and industry reports, to produce a comprehensive analysis of how climate change is altering the world.

Since 2018, the IPCC has published six in-depth special reports. The current one is an overarching summary of the key findings, the first synthesis report to be published in five years.

Although the scientific report is independent, representatives from 195 countries vote on the content of the summary and the recommendations to policymakers. As a result, the final wording often becomes vague.

"The summary is also a measure of what countries are already implementing," said Annika Schröder, a climate expert at the German development organization Misereor.

Schröder told DW that mechanims for capturing and removing CO2 from the atmosphere, for example, have been given too much prominence in climate change mitigation scenarios.

Some of the carbon dioxide removal technologies mentioned in the report are not yet ready for the mass market. While it may be true that the average temperature could be partially lowered with such methods, the IPCC pointed out that the damage caused by the melting glaciers, vanishing Arctic ice or rising sea levels cannot be reversed.

Climate damage could cost billions

A recent estimate from the German Environment Agency showed that the damage caused by climate change in Germany alone could amount to as much as €900 billion ($962.5 billion) by 2050. Speeding up the global response to rising temperatures could theoretically save billions.

Schröder said investment and research into CO2 removal technologies must be carried out. But when it comes to climate protection, she said, we should not wait until they are ready. "And this is the great danger in the IPCC report."

Matthias Garschagen of Ludwig Maximilian University in Munich said the potential for carbon reduction technologies might make it tempting to ease up on drastic emissions cuts. But he advised against that course of action. "From a risk perspective, it's not tempting. It has serious risks. We should really try to avoid this," he said.

Nina Seega, research director for sustainable finance at the Cambridge Institute for Sustainability Leadership, pointed out that mitigation and adaptation costs have dramatically dropped over the last decade. "Against the backdrop of a brewing banking crisis, there is an opportunity for all financial actors to work together to better align the financial system to a net zero, nature positive and equitable economy," she said.

"A rapid and equitable phaseout of all fossil fuels and a shift to renewable energy is essential and also holds great potential for sustainable development around the world," added Sven Harmeling, global policy lead with the NGO CARE Climate Justice Center.

What does 1.5 degrees and beyond look like?

Every tenth of a degree that the planet warms makes a difference — it can determine whether entire ecosystems collapse, island states are washed away or coastal regions become uninhabitable.

Limiting warming to 1.5 degrees instead of 2 degrees, for example, would avert around 10 centimeters (nearly 4 inches) of global sea level rise by 2100. That half a degree difference would likely mean that Antarctica would be ice-free only one summer per century, instead of once per decade. Even at 2 degrees of warming, 99% of the world's coral reefs would be lost.

Heavy rains, which previously occurred just once a decade, have already become 30% more likely. But with another 3 degrees of warming, intense storms are set to occur two or even three times per decade, releasing one-third more water.

Droughts which used to happen, on average, once every 10 years, could render the soil infertile four times per decade. Heat waves, already 2.8 times more likely and 1 degree hotter than in the 19th century, will become 9.4 times more likely and 5 degrees hotter.

"Climate justice is crucial because those who have contributed least to climate change are being disproportionately affected," said Aditi Mukherji, an expert on climate change adaptation with the International Water Management Institute and one of the report's co-authors.

'Massive, simultaneous action' needed right now

There are countless ways to produce fewer greenhouse gases, be it through a diet that includes less meat, electrifying transportation, converting the steel industry to hydrogen, ending fossil fuel subsidies, expanding public transportation or protecting biodiversity and forests.

To prevent irreversible climate change, "massive, simultaneous action" is needed right now, said Tom Mitchell, executive director of the policy and research organization, the International Institute for Environment and Development. "Whether we like it or not, the only option is one of solidarity and shared responsibility, where everyone has to do their part."

Limiting the climate crisis requires more than just action on the country level. The ecological footprint of cities and regions, agriculture and consumer behavior would also have to be reduced to a minimum.

The first priority, however, is a rapid phaseout of coal, oil and gas and the simultaneous electrification of the global energy system, mainly based on wind and solar power. Here, at least, is some good news: the cost of renewable energy has fallen by up to 85% since 2010.