NASA confirms that 2023 is the hottest year in history

NASA's Goddard Institute for Space Studies (GISS) has declared that 2023 secured its place in history as the warmest year on record. The announcement comes after an extensive analysis of global temperature data, showcasing a concerning deviation of approximately 2.1 degrees Fahrenheit (1.2 degrees Celsius) above the average for NASA's baseline period from 1951 to 1980.

As the world struggles with the impacts of extreme weather events, rising sea levels, and unprecedented heatwaves, NASA Administrator Bill Nelson stressed the urgency of addressing the climate crisis. "NASA and NOAA’s global temperature report confirms what billions of people around the world experienced last year; we are facing a climate crisis," said Nelson.

From soaring temperatures to devastating wildfires, the Earth's changing climate is evident. The Biden Harris Administration, alongside NASA, is actively engaged in combating climate risks and building resilient communities. "There’s still more work to be done, but President Biden and communities across America are taking more action than ever to reduce climate risks," added Nelson.

The year 2023 witnessed millions worldwide experiencing extreme heat, setting monthly global temperature records from June through December. July, in particular, stood out as the hottest month ever recorded. The overall temperature anomaly for Earth was about 2.5 degrees Fahrenheit (1.4 degrees Celsius) warmer in 2023 than the late 19th century average when modern record keeping began.

The heat is driven by fossil fuel emissions Gavin Schmidt, director of GISS, emphasized the unprecedented nature of the warming. "The exceptional warming that we’re experiencing is not something we’ve seen before in human history. It’s driven primarily by our fossil fuel emissions, and we’re seeing the impacts in heatwaves, intense rainfall, and coastal flooding," said Schmidt.

Despite conclusive evidence linking the planet's long term warming trend to human activity, scientists continue to examine other factors contributing to yearly or multi year changes in climate. These factors include phenomena such as El Niño, aerosols, pollution, and volcanic eruptions. The El Niño – Southern Oscillation ocean climate pattern in the Pacific Ocean, a major source of year to year variability, saw a transition from La Niña to El Niño in May 2023.

While El Niño tends to coincide with the hottest years on record, the record temperatures in the latter half of 2023 occurred before the peak of the current El Niño event. Scientists anticipate the biggest impacts of El Niño in February, March, and April. A factor in the analysis was the investigation into the potential impacts of the January 2022 eruption of the Hunga Tonga Hunga Ha’apai undersea volcano.

The eruption released water vapor and fine particles, or aerosols, into the stratosphere. A recent study found that the volcanic aerosols, by reflecting sunlight away from the Earth’s surface, led to a slight overall cooling of less than 0.2 degrees Fahrenheit (0.1 degrees Celsius) in the Southern Hemisphere following the eruption.

Schmidt highlighted the need for sustained efforts to address the rising greenhouse gas emissions. "Even with occasional cooling factors like volcanoes or aerosols, we will continue to break records as long as greenhouse gas emissions keep going up," he stated. The significance of urgent and continued actions to address climate change was underscored by NASA Deputy Administrator Pam Melroy.

"The record setting year of 2023 underscores the significance of urgent and continued actions to address climate change," said Melroy. Recent legislation has delivered the U.S. government’s largest ever climate investment, including billions to strengthen America’s resilience. Building on decades of research, the Biden Harris Administration, in collaboration with NASA and federal partners, launched the U.S.

Greenhouse Gas Center. This initiative aims to make critical climate data readily available to decision makers and citizens. This . NASA's complete dataset of global surface temperatures through 2023, along with detailed information on the analysis, is publicly accessible from GISS. GISS, a NASA laboratory managed by the Earth Sciences Division, is affiliated with Columbia University’s Earth Institute and School of Engineering and Applied Science in New York..