Human-induced climate change is causing dangerous and widespread disruption in nature and affecting billions of lives all over the world, says the report of the second working group of the Intergovernmental Panel on Climate Change (IPCC).

Scientists today delivered a stark warning about the impact of climate change on people and the planet, saying that ecosystem collapse, species extinction, deadly heatwaves and floods are among the “unavoidable multiple climate hazards” the world will face over the next two decades due to global warming.

“This report is a dire warning about the consequences of inaction,” said Hoesung Lee, Chair of the Intergovernmental Panel on Climate Change (IPCC).

“It shows that climate change is a grave and mounting threat to our wellbeing and a healthy planet. Our actions today will shape how people adapt and nature responds to increasing climate risks,” he said, adding: “Half measures are no longer an option.”

According to the report, human-induced climate change is causing dangerous and widespread disruption in nature and affecting billions of lives all over the world, despite efforts to reduce the risks, with people and ecosystems least able to cope being hardest hit.

This is the second in a series of three reports from the UN’s top climate scientists and its launch comes just over 100 days since the UN climate action summit in Glasgow, COP26, agreed to step up action to limit global warming to 1.5°C and stave off the worst effects of climate change.

Clobbered by climate change

UN Secretary-General António Guterres had called the first report, issued last August, a “code red for humanity”, and said that “If we combine forces now, we can avert climate catastrophe.”

Guterres’ take on the latest report is equally stark: he laments that the evidence detailed by IPCC is unlike anything he has ever seen, calling it an “atlas of human suffering and a damning indictment of failed climate leadership.”

With fact upon fact, the report, focusing on impacts, adaptation and vulnerability, reveals how people, and the planet, are getting “clobbered” by climate change.

“Nearly half of humanity is living in the danger zone – now. Many ecosystems are at the point of no return – now. Unchecked carbon pollution is forcing the world’s most vulnerable on a frog march to destruction – now,” he declared, adding that the world’s biggest polluters are guilty of arson of our only home.

In the face of such dire evidence, it is essential to meet the goal of limiting global temperature rise to 1.5 degrees, and the science shows that will require the world to cut emissions by 45 percent by 2030 and achieve net zero emissions by 2050.

According to current commitments, global emissions are set to increase almost 14 per cent over the current decade.

Urgent action to tackle increasing risks

The IPCC says that increased heatwaves, droughts and floods are already exceeding plants’ and animals’ tolerance thresholds, driving mass mortalities in species such as trees and corals. These weather extremes are occurring simultaneously, causing cascading impacts that are increasingly difficult to manage.

They have exposed millions of people to acute food and water insecurity, especially in Africa, Asia, Central and South America, on Small Islands and in the Arctic.

To avoid mounting loss of life, biodiversity and infrastructure, ambitious, accelerated action is required to adapt to climate change, at the same time as making rapid, deep cuts in greenhouse gas emissions.

So far, progress on adaptation is uneven and there are increasing gaps between action taken and what is needed to deal with the increasing risks, the new report finds. These gaps are largest among lower-income populations.

“This report recognizes the interdependence of climate, biodiversity and people and integrates natural, social and economic sciences more strongly than earlier IPCC assessments,” said Hoesung Lee.

Protecting nature is key

There are options to adapt to a changing climate. The report provides new insights into nature’s potential not only to reduce climate risks but also to improve people’s lives.

“Healthy ecosystems are more resilient to climate change and provide life-critical services such as food and clean water”, said IPCC Working Group II Co-Chair Hans-Otto Pörtner.

“By restoring degraded ecosystems and effectively and equitably conserving 30 to 50 per cent of Earth’s land, freshwater and ocean habitats, society can benefit from nature’s capacity to absorb and store carbon, and we can accelerate progress towards sustainable development, but adequate finance and political support are essential.”

Scientists point out that climate change interacts with global trends such as unsustainable use of natural resources, growing urbanization, social inequalities, losses and damages from extreme events and a pandemic, jeopardizing future development.

“Our assessment clearly shows that tackling all these different challenges involves everyone – governments, the private sector, civil society – working together to prioritize risk reduction, as well as equity and justice, in decision-making and investment,” said IPCC Working Group II Co-Chair Debra Roberts.

Cities: Hotspots of climate risks

The report provides a detailed assessment of climate change impacts, risks and adaptation in cities, and urban areas, where more than half the world’s population lives.

“Together, growing urbanization and climate change create complex risks, especially for those cities that already experience poorly planned urban growth, high levels of poverty and unemployment, and a lack of basic services,” Ms. Roberts said.

“But cities also provide opportunities for climate action – green buildings, reliable supplies of clean water and renewable energy, and sustainable transport systems that connect urban and rural areas can all lead to a more inclusive, fairer society.”

Equity and justice

Overall, the report, which provides extensive regional information to enable Climate Resilient Development, underlines the urgency for climate action, focusing on equity and justice.

Adequate funding, technology transfer, political commitment and partnership lead to more effective climate change adaptation and emissions reductions.

“The scientific evidence is unequivocal: climate change is a threat to human wellbeing and the health of the planet. Any further delay in concerted global action will miss a brief and rapidly closing window to secure a liveable future,” said Hans-Otto Pörtner.