Prominent scientists issue a dire warning of an “existential threat” to life on Earth in the face of unprecedented climate change impacts, as they assess the alarming surge in heat records and extreme weather events in 2023. With projections indicating that 2023 is poised to become the hottest year on record, numerous regions worldwide are reeling from devastating heatwaves, floods, and in some instances, the devastating combination of both.
In their comprehensive report published in the journal BioScience, an international coalition of researchers expresses deep concern about the unanticipated severity of extreme weather events in 2023, asserting that we have ventured into uncharted territory. Their stark conclusion is that “Life on planet Earth is under siege.”
The authors lament the minimal progress made by humanity in curbing planet-heating emissions, with major greenhouse gases reaching record levels and fossil fuel subsidies surging last year. This sobering assessment arrives just ahead of the UN COP28 climate negotiations scheduled to take place in the oil-rich United Arab Emirates.
The study, which examines the state of the climate, scrutinizes recent data encompassing 35 planetary “vital signs” and reveals that a staggering 20 of these indicators have reached unprecedented extremes this year.
Remarkably, a mere 1.2 degrees Celsius of temperature rise above pre-industrial levels has initiated a cascade of catastrophic and economically burdensome consequences. The year has also marked the onset of a warming El Nino weather phenomenon.
The Copernicus Climate Change Service of the European Union reports that the three months leading up to September marked the hottest period ever recorded, potentially spanning 120,000 years. Many climate-related records have been shattered by substantial margins, particularly regarding ocean temperatures, which have absorbed the bulk of the excess heat generated by human carbon emissions. Sea surface temperatures, in particular, have confounded scientists by defying explanation.
The potential consequences of these record-breaking temperatures encompass threats to marine life, coral reefs, and heightened intensity in large tropical storms.
Globally, people have grappled with heatwaves, droughts, and severe flooding, with record wildfires in Canada, partly attributed to climate change, emitting more carbon dioxide than the country’s total greenhouse gas emissions in 2021.
Prior to 2023, days with global average temperatures exceeding 1.5°C above pre-industrial levels were rare. However, this year had already witnessed 38 such days by mid-September. The more ambitious target set by the Paris Agreement of limiting warming to 1.5°C will be evaluated over decades. Nevertheless, lead author William Ripple, a professor at Oregon State University, warns that we may be entering an era where annual temperatures regularly surpass this threshold, risking the activation of dangerous climate feedback loops and tipping points.
These tipping points could encompass the disintegration of ice sheets in Greenland and West Antarctica, permafrost thawing on a massive scale, and widespread coral reef die-off. While some of these points may be inevitable, efforts to mitigate the damage remain critical.
According to co-author Tim Lenton, director of the Global Systems Institute at the University of Exeter, it is crucial to slash emissions and limit temperature rise, emphasizing that every fraction of a degree matters. The consequences of inaction could result in intolerable conditions for billions of people in the coming decades, such as extreme heat, food scarcity, and climate extremes. The report suggests that by the end of the century, three to six billion people could be forced into areas with inhospitable living conditions.
The scientists express their hope that recent extreme weather events will galvanize policymakers at the forthcoming COP28 climate conference to endorse substantial reductions in fossil fuel emissions and increased support for climate adaptation, especially in the world’s most vulnerable regions.