“The report is speaking very clearly and powerfully to impacts that are unfolding and already affecting people and ecosystems,” says Rachel Cleetus, the policy director and lead economist for the Climate and Energy Program at the nonprofit Union of Concerned Scientists and a civil society observer to the process that created the report, the second in a series of three reports from the IPCC based on the latest climate science. “These will get significantly worse if we fail to sharply curtail emissions, as well as invest in adaptation. So, it’s a very clear message that we need to work on both fronts urgently—both adaptation and mitigation.”

Since 1850, humans have dumped more than 2,400,000,000,000 tons of CO2 emissions into the atmosphere, pushing the global average temperature up by around 1.1 degrees Celsius. The report details the impact of the global warming that’s happened so far: Hurricanes are getting more destructive as the sea level rises and storms get more intense. The areas burned by wildfires are getting larger and fires are becoming more frequent. Coral reefs are bleaching in hotter seawater, and droughts and heat are causing mass deaths of trees in forests. New science is showing the connection between climate change and health, from new pregnancy risks, to mental health impacts, to an increased spread of vector-borne diseases. Deaths from extreme heat are growing. In some regions, fishery yields are dropping and it’s getting harder for farmers to grow crops, impacting food security. That’s just a partial list of the problems.

“One of the most striking conclusions in our report is that we’re seeing adverse impacts being much more widespread, and being much more negative than expected in prior reports,” Camille Parmesan, a climate scientist and one of the authors of the report, said in a press conference on Sunday. That includes, among other things, the fact that dying trees and the melting permafrost are affecting the ability of the biosphere to help capture some of the excess CO2 in the atmosphere. “In some places, even in areas that are undisturbed, such as intact old growth Amazon rain forest, and parts of the permafrost in undisturbed areas in northern North America and northern Siberia, are starting to turn from being overall net sinks of carbon—so sucking up more carbon than they put out—to turning into overall net sources of carbon,” she says.

Climate migration is already beginning as people find it harder to survive in some of the most impacted areas. Climate change isn’t affecting the world equally: The report notes that over the last decade, the number of deaths from floods, droughts, and storms in the most vulnerable regions was 15 times higher than in areas with low vulnerability. Still, climate change is impacting people everywhere. In North America, for example, climate change impacts “have been occurring faster and will become more severe, much sooner than we had previously thought,” Sherilee Harper, one of the coauthors of the report and a public health professor at the University of Alberta, said in the press conference. That includes extreme events like the heat wave that killed hundreds of people in the Pacific Northwest last year, along with droughts and floods impacting crops, rising sea levels along coasts, and more.

Nature is struggling to adapt. Around half of the species that have been studied globally are moving to higher elevations or toward the poles as the world gets hotter. Hundreds of species have already been lost in local areas because of extreme heat. As warm weather comes earlier after winter, some flowers are blooming out of sync with the rest of their ecosystems. Some species have already been driven extinct by climate change. All of this isn’t just a major problem for nature, but also for humans, since we’re dependent on “ecosystem services” for basic needs like food.

There are hard limits to how much the world can adapt to these changes, the report says. The species that have already gone extinct have already reached that limit. Ecosystems like coral reefs may be approaching their hard limits. In some cases, adaptation is possible, but needs much more investment. Some of the poorest and most vulnerable communities need more funding to adapt.

The right investments in adaptation also need to happen—efforts to adapt to an isolated problem without looking at the big picture can not only not help, but can sometimes make things worse; the report calls this “maladaption,” such as building seawalls along coasts or suppressing wildfires in areas where fires naturally happen, making future fires more severe. The report also highlights the need to approach adaptation with climate justice in mind. And, most critically, emissions need to drop much faster than they currently are. If the world breaks past the goal of limiting global warming to 1.5 degrees Celsius, there’s more risk of systems reaching hard limits where adaptation is no longer possible.

“The world has to know we cannot cope with runaway climate change,” Cleetus says. “We cannot adapt to runaway climate change. And that’s why cutting emissions is also really critical to build resilience.”