In a historic milestone, August 2024 set a new record for the hottest summer month globally, capping off the warmest summer ever documented since 1880. Scientists at NASA’s Goddard Institute for Space Studies (GISS) confirmed the findings, highlighting that the summer of 2024 was approximately 2.25°F (1.25°C) warmer than the average summer between 1951 and 1980. This continues the trend of rising global temperatures due to human-induced climate change, and the agency’s temperature record, GISTEMP, remains a vital tool in tracking these shifts.
NASA’s data reveals that June, July, and August 2024 were about 0.2°F (0.1°C) warmer globally than any previous summer on record, narrowly surpassing the heat wave of 2023. The global temperature increase aligns with the broader warming trend seen in recent decades, with August alone 2.34°F (1.3°C) above the 1951-1980 average.
According to Gavin Schmidt, director of GISS, “This is a clear indication of the ongoing human-driven warming of the climate.” The ElNiño phenomenon has likely amplified these temperatures, but the magnitude of the increase underscores the urgency of addressing climate change.
HOW NASA MEASURES GLOBAL TEMPERATURE
NASA’s GISTEMP assembles data from tens of thousands of meteorological stations, sea surface temperature measurements, and Antarctic readings. The analysis focuses on temperature anomalies, comparing current temperatures to the baseline average from 1951 to 1980. This approach helps scientists understand how today’s temperatures deviate from the mid-20th century climate.
Additionally, the GISTEMP method accounts for urban heat effects and uneven station distribution to ensure that temperature readings are accurate across both populated and remote areas.
NEW ASSESSMENT SUPPORTS NASA’S CLIMATE DATA
A recent study by scientists from NASA, the Colorado School of Mines, and the National Science Foundation reaffirms the accuracy of the GISTEMP temperature record. The analysis shows that NASA’s global temperature estimates are reliable to within a tenth of a degree Fahrenheit in recent decades, bolstering confidence in the data.
Lead author Nathan Lenssen emphasized that the research aims to quantify the accuracy of temperature estimates over time. The study confirmed that Earth’s average temperature in summer 2024 was about 2.7°F (1.51°C) warmer than the late 1800s, ruling out any significant data uncertainty that could affect the findings.
ADDRESSING UNCERTAINTY: NEW METHODS OF TEMPERATURE ESTIMATION
The new study highlights how statistical uncertainty plays a role in interpreting temperature data. Previously, scientists relied on confidence intervals to represent uncertainty. Now, the statistical ensemble approach allows for a more comprehensive range of possible temperatures, giving scientists a clearer picture of past climates, especially in areas where direct measurements were limited.
This method has helped NASA refine its understanding of global temperature trends. For instance, while July 2023 was initially ranked as the hottest month, the new ensemble analysis shows that July 2024 may have had a narrow edge, though the difference falls within the margin of uncertainty.
CLIMATE CONTEXT: UNDERSTANDING THE ONGOING TREND
NASA’s annual global temperature updates reveal that the past few years are some of the hottest in recorded history. Not only do records from 2024 surpass previous years, but the trend points toward an acceleration of global warming.
Agencies like NOAA and the Copernicus Climate Change Service (in the EU) also track global temperatures using independent methods. While the findings may vary slightly, they largely agree with NASA’s conclusions: the planet is warming at an unprecedented rate.