In January 2025, the world experienced another monthly heat record, with temperatures 0.09 degrees Celsius (0.16 degrees Fahrenheit) warmer than the previous record set in January 2024. This month's temperatures were 1.75 degrees Celsius (3.15 degrees Fahrenheit) above pre-industrial levels, marking the 18th out of the last 19 months that global heat has surpassed the internationally agreed warming limit of 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial times, according to the European climate service Copernicus.
Despite the record heat globally, the United States experienced an unusually cold January. The prevailing scientific opinion suggests that the natural cooling effects of La Niña, which have recently taken hold, could have dampened global temperatures. La Niña typically leads to cooler conditions in the equatorial Pacific and moderates the overall impact of global warming. However, Copernicus noted that even with these natural conditions, record warmth was still recorded due to extraordinary heat in oceans worldwide.
This unexpected heat coincided with a new study by prominent climate scientist James Hansen, a former NASA official, suggesting that global warming is accelerating. This claim has sparked debate within the research community, with some scientists aligning with Hansen while others argue against the notion of acceleration based on the data available.
Over the past 15 years, global temperatures have been rising at approximately twice the rate of the previous 40 years, according to Hansen. He expressed confidence that this trend of increased warming will persist for several years to come, and suggested that 2025 could potentially rival or exceed 2024 in temperature records.
January also registered unseasonably mild weather in the Arctic, where temperatures in parts of the Canadian Arctic were reported to be as much as 30 degrees Celsius (54 degrees Fahrenheit) above average. Consequently, this led to some areas witnessing sea ice melting, contributing further to the alarming sea ice levels, which were among the lowest recorded by Copernicus for January.
While climate scientists expected that temperatures would decline following the substantial El Niño event of the previous year, which ended in June, the anticipated drop did not occur. Instead, climate expert Samantha Burgess remarked that, “Even though the equatorial Pacific isn’t creating conditions that are warming for our global climate, we’re still seeing record temperatures.” This rise in ocean temperatures is partially attributed to the ongoing effects of climate change and greenhouse gas emissions from fossil fuels.
As the year unfolds, February has already started cooler than the preceding year. However, experts remain cautious about dismissing 2025's potential for becoming one of the hottest years on record. The debates surrounding the implications of these temperatures and the future trajectory of global warming are ongoing, with differing opinions regarding the data and its interpretations.
Overall, the January phenomenon serves as a stark reminder of the profound impacts of climate change, highlighting the increasing urgency for global awareness and action on environmental issues. The continued rise in temperatures, even alongside natural cooling phenomena, underlines the challenges faced in mitigating climate change and its effects worldwide.
