2024 marks a critical juncture in Earth's climate history as it becomes the first year to exceed the 1.5°C warming threshold. The global average temperature reached an unprecedented 15.10°C, a stark reminder of the escalating implications of climate change. This milestone is not merely a statistical anomaly but a reflection of the cumulative effects of human activities and natural phenomena, such as the El Niño-Southern Oscillation, which have accelerated planetary warming beyond previous projections.
The year 2024 shattered global average temperature records dating back to 1850, with the temperature exceeding 1.5°C above pre-industrial levels (1850–1900) for the first time in recorded history. According to Carlo Buontempo, Director of the Copernicus Climate Change Service, "All of the internationally produced global temperature datasets show that 2024 was the hottest year since records began in 1850. Humanity is in charge of its own destiny but how we respond to the climate challenge should be based on evidence. The future is in our hands – swift and decisive action can still alter the trajectory of our future climate."
Furthermore, Buontempo emphasized that while this milestone is grim, it does not make the situation irreversible. "It's not a done deal. We have the power to change the trajectory from now on," highlighting the urgency and opportunity for collective action to mitigate further warming.
The implications of this record-breaking heat are multifaceted, with record warmth recorded during boreal winter, spring, and summer, and monthly anomalies that have significantly surpassed historical averages. The extreme temperatures have had deadly consequences worldwide, underscoring the need for rapid and decisive responses to the climate challenge. As the world navigates this pivotal moment, the question is no longer whether climate change is happening but what societies will face as these temperature records continue to fall.
Global Temperature Shatters Records
Three major temperature records fell in 2024 as Earth experienced its hottest year since measurements began in 1850. The global average temperature reached 15.10°C, surpassing the 2023 record by 0.12°C, according to ECMWF's ERA5 reanalysis. For the first time, the planet's average temperature temporarily exceeded the critical 1.5°C threshold above pre-industrial levels, a milestone that underscores the urgent need for sustained global action to combat climate change.
Sea surface temperatures reached a record high of 20.87°C average throughout the year, intensifying extreme weather patterns worldwide. Notably, 2024 set new records not only for annual global temperatures but also for monthly temperatures, with each month from January to June being warmer than any corresponding month in previous years. The year's exceptional warmth was partly driven by human-induced climate change and the El Niño–Southern Oscillation (ENSO), highlighting the complex interplay of factors influencing Earth's climate.
Gavin Schmidt, director of NASA's Goddard Institute for Space Studies, pointed out the broader implications of the 1.5°C threshold, stating, "We are halfway to Pliocene-level warmth in just 150 years," and noting that temperatures during warm periods on Earth three million years ago, when sea levels were dozens of feet higher than today, were only around 3°C warmer than pre-industrial levels.
Florence Rabier, ECMWF Director-General, emphasized the importance of accurate climate data, saying, "The Global Climate Highlights is a vital tool for supporting international climate adaptation efforts," and underscoring the organization's commitment to providing reliable climate information.
Breaking Paris Agreement Benchmarks
New analysis indicates that the Paris Agreement's 1.5°C target is receding faster than anticipated, as Earth continues to break temperature records. The current projection suggests that the world will cross this critical threshold by the early 2030s, a timeframe significantly earlier than initially expected. This acceleration in warming underscores the urgent need for decisive action in reducing greenhouse gas emissions.
According to Dr. Robert Rohde, lead scientist at Berkeley Earth, "The abrupt new records set in 2023 and 2024 join other evidence that recent global warming appears to be moving faster than expected." He further emphasizes that "Already though the Paris Agreement target of staying below 1.5°C is unobtainable, and the long-term average will pass this milestone within the next five to 10 years."
Moreover, the Climate Action Tracker underscores that current national climate targets, or Nationally Determined Contributions (NDCs), are insufficient to meet the Paris Agreement goals. To stay below 1.5°C, global greenhouse gas emissions must peak immediately and decrease rapidly thereafter, with a target of achieving net zero CO2 emissions globally by 2050[1,3].
The implications of failing to meet these targets are severe. The current emissions path could lead to a devastating 3°C rise in global temperatures, unless there's a rapid transformation in the approach to decarbonization. Strong emission reductions must achieve a 43% decrease by 2030 from 2019 levels to maintain a chance at limiting warming. Therefore, it's crucial that countries submit new and updated NDCs aligned with the 1.5°C goal and implement them fully to avoid higher levels of warming and mitigate more significant impacts from extreme weather events.
The urgency of the situation can't be overstated. As Dr. Rohde notes, "Given the apparent increase in warming, and the uncertainty around future warming rates, the need for access to accurate and reliable data and modeling tools to inform adaptation and resilience planning is more important than ever."
Worldwide Climate Impact Evidence
The escalating global climate impacts in 2024 underscored the dire warnings from scientists about surpassing the targets set forth by the Paris Agreement. This is evident in the unprecedented heat waves that enveloped nearly one-third of U.S. cities and 31% of the analyzed 243 cities, with global temperatures reaching new highs.
The year's data revealed that carbon dioxide levels soared to unprecedented heights not seen in 2 million years, while ocean temperatures broke new records. Antarctic sea ice, too, plummeted to near historic lows, marking the second-lowest maximum extent in the 46-year satellite record. The international community's Early Warnings for All initiative emerged as a critical response to these environmental challenges.
These climate extremes led UN Secretary-General António Guterres to state, "This is climate breakdown — in real time," emphasizing the need for urgent action to slash emissions and transition to a renewable future.
The global average temperature anomaly exceeded 1.5°C above pre-industrial levels for the first time, surpassing the key long-term threshold set by the Paris Climate Accord. This acceleration in temperature rise has puzzled scientists, with some speculating that the planet may have entered a new state of rapid warming.
Ted Scambos, senior research scientist at the Cooperative Institute for Research in Environmental Sciences (CIRES) at CU Boulder, noted, "The dramatic downward step in southern winter sea ice spanning the past two years points more than ever to effects from a record-warm ocean on Antarctic climate," highlighting the profound impact of climate change on polar regions.