The United Nations’ Intergovernmental Panel on Climate Change published part two of its report on climate change — and the findings are dire. UN Secretary General António Guterres called it “an atlas of human suffering and a damning indictment of failed climate leadership.” Others called it the “bleakest warning yet.”
The report is the second of a four-part scientific analysis of the climate and global efforts to stop climate change. (→Read our breakdown of the first report here.) The latest installment takes a detailed look at the interrelated impacts of climate change based on seven years of research.

Though hefty, the 3,675-page update doesn’t mince words: It’s time to act. “The cumulative scientific evidence is unequivocal: Climate change is a threat to human well-being and planetary health,” the report reads. “Any further delay in concerted anticipatory global action on adaptation and mitigation will miss a brief and rapidly closing window of opportunity to secure a liveable and sustainable future for all.”
So, without further ado, let’s dive into some of the key findings:
1. The impacts of climate change are worse than we thought.
We are already experiencing the effects of human-induced climate change around the world via extreme temperatures and weather events, flooding, drought and wildfires. Species are migrating and dying off. Roughly half of the people on the planet face severe water scarcity for at least part of each year. And many of the changes underway are irreversible, such as glacier retreat, permafrost thaw and coral reef extinction.
“The extent and magnitude of climate change impacts are larger than estimated in previous assessments,” the report reads. While the global target has long been to limit warming to 1.5°C above pre-industrial levels, even then we can expect to see “widespread, pervasive, and potentially irreversible” damage. The IPCC estimates up to 14% of species in land-based ecosystems could face extinction at the 1.5°C mark.
2. The window to act is closing fast.
“There is a rapidly narrowing window of opportunity to enable climate resilient development,” the IPCC says. We still have multiple pathways to better climate resilience. However, with every incremental increase in temperature, the options for adaptation narrow. And the longer we wait, the less effective those interventions become.
Scientists estimate that the planet is currently 1.1°C above pre-industrial temperatures. The likelihood that the planet will reach or exceed the 1.5°C target in the near term is over 50%. At that point, we will see significant biodiversity loss, particularly in aquatic and forest ecosystems and the arctic. Sea level rise will encroach on coastal cities and low-lying islands. And if we overshoot the 1.5°C mark, we risk releasing additional greenhouse gases that will have additional irreversible effects, even if global warming is subsequently reduced. In short — it’s crunch time.
3. Risk is not evenly distributed.
The people and places that will be hit the hardest by climate change will often be those least equipped to handle it. This includes low-lying islands that will disproportionately shoulder the burden of rising sea levels and mountainous regions where residents depend on climate-sensitive livelihoods. It also includes lower-income people all over the world, as stress on agricultural systems leads to more inaccessible food prices. In the last decade, mortality from extreme weather was 15 times higher in vulnerable regions, the report notes.
While the impacts of climate change are unevenly distributed, so too are the opportunities for climate-resilient development. As such, the adaptation and mitigation efforts must be considered through a lens of global equity.

4. The worst outcomes can still be avoided.
There was a tiny beacon of hope buried in the report — climate-resilient development is still possible and very much within reach. For example, early warning systems can help save lives amid flooding and better irrigation can improve water access in drought-prone areas. Vaccine development and surveillance can help limit health-related risks. And in many cases, there is still opportunity to overcome what the IPCC calls “soft limits” through more equitable policies and distribution of resources.
In fact, some of the areas most at risk also present critical opportunities. The IPCC underscores the importance of investing in sustainable urban infrastructure, especially in coastal cities, to help maintain supply chains and financial flows to all regions.
5. We must work together, across borders and sectors, to succeed.
Perhaps most importantly, the report emphasized the interrelated nature of climate change risks and our capacity to adapt. Climate-related hazards are complex and compounding. For example, sea level rise, combined with storm surges and heavy precipitation, compounds flood risks. This, in turn, can destroy natural habitats, wipe out crops, degrade water quality, spread disease and put communities at risk. As such, narrow solutions can have a damaging effect. A seawall might reduce short-term risks but can cause lock-ins and other risks down the line.
Climate-resilient development must be broad, incorporating multiple sectors and risks, while balancing near- and long-term benefits. It must also prioritize the protection of vulnerable and marginalized communities. “When implementing adaptation and mitigation together, and taking trade-offs into account, multiple benefits and synergies for human well-being as well as ecosystem and planetary health can be realised,” the report notes.