our planet Hottest January on record It also helped global warming pass a different and untimely milestone, according to data released Thursday by the European Union’s climate monitor: Over the past 12 months, the average temperature around the world was more than 1.5 degrees Celsius, or 2.7 degrees Fahrenheit, higher than it was. at the dawn of the industrial era.
That figure has special importance in the international effort to stop dangerous climate change. Under the 2015 Paris AgreementNations agreed to try to limit global warming to 1.5 degrees Celsius compared with pre-industrial times, or at least keep it comfortably below 2 degrees Celsius.
The latest temperature data does not mean that we have already surpassed that lower limit. Still, it is a powerful symbolic reminder that, barring major changes in the climate or the global economy, we are headed in that direction in the coming years.
This is what you should know.
What are the objectives of 1.5 and 2 degrees?
It might be useful to start with what they are not, which are thresholds encoded somewhere in the laws of nature. Rather, they represent levels of warming that would bring consequences that are unacceptably difficult for societies to manage, as decided and agreed upon by the nearly 200 nations that signed the Paris agreement.
Deadlier heat waves. Higher sea levels. Greater loss of biodiversity. Longer droughts and fiercer storms. Scientists agree that these and other effects of a warmer Earth would increase significantly if warming continued well beyond recent levels. Temperature targets therefore represent barriers that humanity must avoid for the sake of our communities, ecosystems and landscapes.
In fact, however, many of these physical consequences of warming are already intensifying as we continue to add heat-trapping gases to the atmosphere by burning fossil fuels. That’s why scientists and diplomats often emphasize that even if we one day warm the planet beyond 1.5 degrees, it will still be worth trying to slow the rise in temperatures beyond 1.6, 1.7. or 1.8.
What would it mean to exceed those thresholds?
The key to the Paris goals is that they are long-term goals. So, technically speaking, we will be sure to have overcome them only after a certain number of years have passed (even, perhaps, only after a certain number of years). after a decade. Researchers say we shouldn’t declare a failure every time the mercury rises above 1.5 degrees for a day, a month or even 12 months.
Multitude of factors: intermittent weather phenomena The Boy and The Girl, volcanic eruptions, plagues and pandemics, not to mention pure chance, influence the planet’s precise temperatures year after year. Those factors are not what the Paris goals are about.
Different climate monitoring agencies also produce slightly different estimates of how hot the planet is at any point, depending on how they combine and analyze the mountains of weather data collected by satellites, sensors and weather balloons. That means the time we might pass those points can vary a bit depending on who is measuring.
According to the European Union Copernicus Climate Change ServiceFor example, 2023 was 1.48 degrees Celsius warmer than the pre-industrial baseline. But according to Berkeley LandAccording to a California research group, the temperature was 1.54 degrees Celsius higher.
How close are we to passing them?
On average over the past few years, humans have caused warming of about 1.2 or 1.3 degrees Celsius since the Industrial Revolution, most estimates suggest. And, based on the current rate of carbon emissionsIt will only be a few more years before we have altered the chemistry of the atmosphere so much that even drastic emissions cuts would not be enough to prevent warming from eventually exceeding 1.5 degrees.
He first official report card on nations’ progress toward achieving the Paris goals, issued last year, was not optimistic. Current governments’ climate pledges would put the world on track for warming of about 2.5 degrees Celsius by 2100, according to the report card. And that’s assuming nations follow through on their stated plans to reduce emissions, a task that is proving difficult more than eight years after the signing of the Paris Agreement.