Today (August 9), the Intergovernmental Panel on Climate Change released a report compiling the planet’s most up-to-date information about climate change. The report, which was written by 234 authors from around the world and cites data from over 14,000 studies, warns policymakers and the public that climate change is unequivocally caused by human action—and that we’re running out of time to reverse it.
According to the report, global temperatures have warmed by about 1.1 degrees Celsius since pre-industrial times, and without any reduction in emissions, within the next 40 years those temperatures will meet or exceed 2.0 degrees Celsius—the cap set by the Paris Accords in 2015.
According to The Washington Post, warming of over 2 degrees Celsius could be enough for Greenland’s ice sheet to melt, which would cause sea levels to rise globally by more than 6 feet. Effects aren’t limited to ice caps and coastal areas, either—“Climate change is already affecting every inhabited region across the globe with human influence contributing to many observed changes in weather and climate extremes,” the report states. These changes include droughts, wildfire-stoking heat waves, and flooding—disasters that have befallen communities across the globe in the last year alone. The report also projects that some damage from carbon emissions, such as acidifying oceans and rising sea levels, could take centuries to millennia to reverse.
United Nations Secretary General António Guterres says in a statement that the findings are “a code red for humanity,” and that leaders from government, business, and civil society must unite behind policies and investments to keep rising temperatures under control. “We owe this to the entire human family,” he says. “There is no time for delay and no room for excuses.”
This report is the sixth of its kind since 1990—and the most recent since 2013—according to Nature, but is distinct from previous reports in a few ways. First, it leaves no room for doubt as to whether or not humans are responsible for the rapidly warming temperatures of the last century. Additionally, Swiss Federal Institute of Technology climate scientist Sonia Seneviratne tells Nature that within the last decade, scientists have developed better statistical models to predict the effects of climate change. She also says that increasing numbers of extreme weather events are evidence of the changing climate.
“It’s now become actually quite obvious to people what is happening, because we see it with our own eyes,” University of East Anglia climate scientist and report contributor Corinne Le Quéré tells the Post. “You don’t have to have a PhD. You don’t need to be a climate scientist. You just need to be a person who looks out the window.”
This report does not offer any policy recommendations or mitigation strategies, but will be followed by two additional reports in the coming months that will offer concrete recommendations to limit carbon emissions. However, Monday’s report does include five projected scenarios, ranging from “business as usual” (the planet continuing its current reliance on fossil fuels) to making dramatic cuts to carbon emissions. At this point, even the most dramatic interventions wouldn't be able to stop the climate from exceeding the 1.5 degrees C threshold before temperatures stabilize and begin cooling—and in the “business as usual” scenario, scientists project the climate would hit 4.4 to 5.7 degrees C higher than preindustrial levels by the end of the century, according to Science.
Despite the sobering projections, officials and activists say that it’s not too late to act.
“From a scientific perspective, every degree, every part of a degree, every half of a degree matters in terms of limiting the impacts that we will see from climate change,” Ko Barrett, former vice chair of the IPCC, tells CNN, and climate scientist and report coauthor Kim Cobb tells Buzzfeed that acting now can help ensure “these next two decades of warming may be some of our last.”
“The new IPCC report contains no real surprises. It confirms what we already know from thousands previous studies and reports—that we are in an emergency,” writes teenage environmental activist Greta Thunberg on Twitter. “It is up to us to be brave and take decisions based on the scientific evidence provided in these reports. We can still avoid the worst consequences, but not if we continue like today, and not without treating the crisis like a crisis.”