According to the Copernicus Climate Change Service’s report released Friday, 2024 not only marked the hottest year on record since observations began in 1850, but also became the first year to exceed a critical limit set by global leaders aiming to mitigate severe consequences of climate change.

The announcement is part of a series of updates expected on this day, as significant climate monitoring agencies like NASA, NOAA, and Berkeley Earth have agreed to deliver annual reports simultaneously.

Carlo Buontempo, the director of Copernicus, stated, “All globally produced datasets indicate that 2024 was the hottest year recorded since 1850.”

The establishment of a new temperature record for two consecutive years has intensified calls from various organizations for more decisive and prompt measures to combat rising temperatures, reduce greenhouse gas emissions, and address the challenges posed by increasingly severe weather events.

This includes events such as the ongoing drought in California, which has contributed to recent wildfires in Los Angeles, and the heavy rainfall that wreaked havoc in Western North Carolina due to Hurricane Helene and its aftermath.

Buontempo emphasized, “The future is within our control; timely and effective actions can still reshape our climate future. Humanity holds the key to its destiny, but our approach to the climate crisis must be grounded in scientific evidence.”

Copernicus has highlighted these major milestones:

• The global average temperature was 1.3 degrees higher than the 1991-2020 global average and 0.21 degrees warmer than 2023, which was the previous record holder.
• The temperature was 2.9 degrees (1.6 C) elevated compared to the average temperatures from 1850-1900, known as the pre-industrial period.
• All of the last ten years have registered among the warmest in history.
• A peak daily global average temperature of 30.8 degrees was recorded on July 22.
• Since July 2023, every month except July 2024 has exceeded the 2.7 degrees Fahrenheit (1.5 C) benchmark.
• Antarctica and Australasia were the only continental regions that did not experience their warmest year on record.

Understanding the significance of the 2.7 degrees threshold

The record temperature in 2024 signifies a threshold that scientists have sought to avert for years.

In 2016, the United States and 195 other nations ratified the Paris Agreement, a treaty designed to limit global warming. They committed to striving to keep the global average temperature rise below 2.7 degrees.

While it may seem like a minor figure, a rise of just 2.7 degrees can drastically affect conditions. It can dictate the difference between a healthy child and one with a fever, a skating rink and a swimming pool, or food staying fresh versus spoiling.

Considering that in 2024, the planet was 2.9 degrees warmer on average compared to the late 1800s, the consequences of this shift are becoming evident.

This increase may not appear substantial—after all, moving from 65 to 67.9 degrees hardly necessitates a sweater—so why the alarm among climate scientists?

The explanation lies in averages; even a slight rise in global averages can lead to major increases in extreme weather events.

This is already observable throughout the United States, where storms are more intense and bring unprecedented amounts of rain, resulting in more frequent and devastating flash floods. Droughts and catastrophic wildfires are also on the rise, and hurricanes are becoming increasingly heavy with rain.

Graph depicting annual temperature deviations from long-term averages

Sea ice conditions

Following record-low levels observed in eight months during 2023, Antarctic sea ice continued to hover at or near record low values throughout much of 2024, ranking as the second lowest on record between June and October, and the lowest in November, according to Copernicus. In February—when ice typically reaches its annual minimum—the extent was recorded as the third lowest in satellite history.

In the Arctic, sea ice extent was nearly in line with its 30-year average from 1991 to 2020 until July, when it began to dip below that average. The annual minimum extent in September marked the fifth lowest in satellite records.

Greenhouse gas emissions trends

The levels of carbon dioxide and methane in the atmosphere climbed again in 2024, reaching record highs at 422 parts per million, as reported by Copernicus. The concentration of carbon dioxide was 2.9 parts per million higher than recorded in 2023. Although carbon dioxide naturally exists in the atmosphere, scientists attribute the significant increase in emissions as a primary reason for the ongoing rise in global temperatures.