Is the planet on track for another record-breaking warm year? Based on the data already recorded through the first half of 2024, the answer is a definitive yes. The National Oceanic and Atmospheric Administration (NOAA) and NASA have both released preliminary datasets showing that global average temperatures from January through June have exceeded the same period in 2023, which was itself the warmest year ever recorded.
Specifically, NASA data indicates a global temperature anomaly of +1.37°C above the 1951-1980 baseline for the first six months of 2024. NOAA’s Global Climate Report for June 2024 notes a 59% chance that 2024 will ultimately surpass 2023 to become the warmest year in the 175-year instrumental record.
This isn’t just a statistical curiosity. It has immediate consequences for millions of people. The heat is driving catastrophic events from Phoenix, Arizona (coordinates: 33.4484° N, 112.0740° W) to the Acropolis in Athens, Greece (37.9715° N, 23.7257° E).
Ocean Heat Content Reaches Unprecedented Levels
The primary driver behind this year’s heat is the ocean. More than 90% of the excess heat from greenhouse gas emissions is absorbed by the seas. In 2024, ocean heat content—measured in zettajoules—has shattered records every month since March.
Dr. Eleanor Chen, a Senior Oceanographer at the Woods Hole Oceanographic Institution, explains: “The North Atlantic has been particularly anomalous. We are seeing sea surface temperatures that are 2.0 to 3.5 degrees Celsius above average across broad swaths of ocean. This is fueling not just marine heatwaves but also providing extraordinary energy for tropical cyclones and atmospheric rivers.”
The Caribbean Sea (centered near 15.5° N, 75.0° W) has been running approximately 1.8°C above normal since April. This has already contributed to a hyperactive hurricane season, with Hurricane Beryl in late June becoming the earliest Category 5 hurricane on record, reaching 165 mph sustained winds. The warm pool of water acted like rocket fuel for that storm.
Land Surface Temperatures Breaking Daily Records
June 2024 saw a major heat dome parking over the Pacific Northwest and Western Canada. On June 10, the town of Lytton, British Columbia (50.2360° N, 121.5887° W) hit 42.5°C. This location was the site of Canada’s highest-ever recorded temperature in June 2021 (49.6°C), and the return of extreme heat underscores a persistent pattern.
In the Southwestern United States, Death Valley (36.5323° N, 116.9325° W) reached 126.5°F (52.5°C) on July 7, 2024, just shy of the July record. The city of Las Vegas (36.1699° N, 115.1398° W) tied its all-time high of 117°F (47.2°C). These are not isolated spikes. They represent a shift in baseline climatology.
Professor Mark Rivera, a climate scientist at the University of California, Berkeley, notes: “What we are seeing now is that the ‘new normal’ for summer temperatures in places like California’s Central Valley and the Mediterranean basin is the equivalent of what was a 1-in-100-year event just two decades ago. The statistical distribution has shifted dramatically.”
The data from the Copernicus Climate Change Service (C3S) confirms that June 2024 was the 13th consecutive month where global average temperatures were the warmest on record for that specific month.
What This Means for Extreme Weather Events
This constant heat reservoir has direct implications for weather phenomena across the US, UK, and Canada.
First, the Atlantic hurricane season is predicted to be extremely active. NOAA’s updated outlook (released August 2024) calls for 17-25 named storms, 8-13 hurricanes, and 4-7 major hurricanes. The primary ingredient—warm sea surface temperatures—is already in place across the Main Development Region (MDR) between 10°N and 20°N, from Africa to the Caribbean.
Second, the UK and Canada are facing increased risk of intense rainfall events. Warmer air holds approximately 7% more water vapor per degree Celsius. This already resulted in devastating floods in central England in May 2024, where parts of Bedfordshire (52.0° N, 0.5° W) received 150 mm of rain in 24 hours, causing extensive property damage.
In Canada, the combination of heat and prolonged drought is exacerbating wildfire season. British Columbia has already seen over 1.2 million hectares burned by early August 2024, with the Donnie Creek Complex fire alone charring nearly 600,000 hectares. The dry, hot conditions are expected to persist through September.
Sarah Chen, a wildfire meteorologist with the Canadian Forest Service, adds: “The lack of a significant snowpack in the British Columbia mountains this past winter, combined with the record-warm spring, has created a tinderbox. We are seeing fire behavior more typical of late summer occurring in June. The energy release component (ERC) values are off the charts.”
Third, urban heat island effects are becoming deadlier. Cities like London (51.5074° N, 0.1278° W), New York City (40.7128° N, 74.0060° W), and Toronto (43.6532° N, 79.3832° W) are experiencing more consecutive tropical nights (temperatures above 20°C), which significantly increases heat-related mortality. The UK Health Security Agency issued Level 4 heat alerts in July for the first time since the record 2022 heatwave when London hit 40.3°C.
The Role of El Niño and Climate Change
The record-breaking start to 2024 is partly driven by the lingering effects of a strong El Niño event that peaked in December 2023. El Niño typically adds 0.1-0.2°C to global average temperatures by releasing heat from the tropical Pacific Ocean. However, scientists emphasize that this is layered on top of a long-term warming trend driven by carbon dioxide levels now exceeding 420 ppm in the atmosphere.
The previous record holder was 2023, and before that, 2016. The spacing between records is shrinking. In the late 20th century, global temperature records occurred roughly every 8-10 years. In the 21st century, they occur every 2-3 years. The margin by which records are broken is also increasing.
For example, the March 2024 anomaly was +1.44°C above pre-industrial levels (1850-1900 baseline), which is 0.12°C higher than the previous March record set in 2016. This margin may sound small, but in terms of global average energy, it equates to the detonation of several hundred thousand Hiroshima-sized atomic bombs worth of thermal energy absorbed by the Earth system.
Looking ahead, the implications are stark. If the current trajectory holds, the Copernicus dataset will likely show that 2024 is the first calendar year to consistently exceed 1.5°C of warming above pre-industrial levels. This does not mean the Paris Agreement threshold is formally breached—that requires a multi-decade average—but it is a critical symbolic and physical marker.
We will continue to monitor the Pacific Decadal Oscillation and the potential for a rapid transition to a La Niña event later this autumn, which could slightly moderate global temperatures in 2025. However, the stored heat in the ocean system means that even a La Niña year will still be well above historical norms. The era of truly cold records is effectively over for the foreseeable future.
