The following is a summary of global temperature conditions in Berkeley Earth’s analysis of April 2024.
- Globally, April 2024 was the warmest April since records began in 1850.
- The previous record for warmest April, set in 2020, was broken by a significant margin (0.14 °C / 0.25 °F).
- The ocean-average and land-average each also set new records for the warmest April.
- Particularly warm conditions occurred in parts of North America, South America, Central Asia, Africa, and large areas of the Atlantic Ocean.
- Australia and parts of Antarctica exhibited unusually cold monthly averages in April.
- 47 countries set new national monthly-average records for April.
- The El Niño that began last year has weakened to a weak category, and is likely to end soon.
- The 12-month moving-average sets a new record at 1.65 ± 0.07 °C (2.97 ± 0.13 °F) above the 1850-1900 average.
- 2024 is very likely to be either the warmest or second warmest year on record.
Global Summary
Globally, April 2024 was the warmest April since directly measured instrumental records began in 1850. It broke the previous record by 0.14 °C (0.25 °F), a relatively large margin clearly outside the range of the uncertainties.
The global mean temperature in April 2024 was 1.67 ± 0.11 °C (3.01 ± 0.19 °F) above the 1850 to 1900 average. This is similar to other recent months, though less warm than the peak set last September.
It is the eleventh consecutive month to set a new monthly record, often by large margins. In addition, April 2024 continues the run started in July 2023 of each individual month being at least 1.5 °C warmer than the 1850 to 1900 average.
One of the Paris Agreement ambitions has been to limit global warming to no more than 1.5 °C (2.7 °F) above the preindustrial baseline. That goal is defined in reference to the average climate over many years, so a few individual months or a single year above 1.5 °C do not automatically mean that the target has been exceeded. However, isolated anomalies above 1.5 °C are a sign that the Earth is getting close to that limit. It is likely that global warming will cause the long-term average to exceed 1.5 °C during the 2030s unless significant reductions in greenhouse gas emissions are achieved soon.
The global mean temperature anomaly in April 2024 was similar to March 2024. We also note that March 2024 was revised +0.03 °C (+0.05 °F) compared to the previous month’s report. Revisions of this magnitude are not uncommon due to delays in data reporting.
After 11 consecutive months of record high monthly averages, the 12-month moving average of global mean temperature now stands at 1.65 ± 0.07 °C (2.97 ± 0.13 °F) above the 1850-1900 average. We are likely at or near the peak for this warming event, as relatively cooling is expected soon with El Niño ending. Compared to the long-term trend, the current deviation is similar in magnitude to that associated with previous very strong El Niño events, such as 1998 and 2016.
Spatial Variation
April 2024 continues the ongoing pattern of widespread warmth, with a few important exceptions. Particularly warm conditions were present in parts of North America, Asia, South America, Africa, and large areas of the Atlantic. Australia and parts of Antarctica exhibited unusually cold monthly averages in April.
We estimate that 12.2% of the Earth’s surface experienced their locally warmest April average (including 15.1% of land areas), and 84% of the Earth’s surface was significantly warm when compared to their local average during the period 1951 to 1980. By contrast, 0.01% of the Earth’s surface had their locally coldest April.
The Equatorial Pacific in April has weakened from moderate to weak El Niño conditions. The El Niño condition was officially declared by NOAA in early June 2023 and is expected to dissipate within a few months.
Over land regions, 2024 was the warmest April ever observed. The land average was 2.47 ± 0.16 °C (4.45 ± 0.28 °F) above the 1850 to 1900 average.
In total, we estimate that 47 countries, mostly in the tropics, had their warmest national-average April on record, these were:
Armenia, Azerbaijan, Bangladesh, Bolivia, Brazil, Burkina Faso, Cambodia, Cameroon, Central African Republic, Chad, China, Colombia, Costa Rica, Cyprus, Djibouti, Ecuador, Federated States of Micronesia, Fiji, Georgia, Guyana, Japan, Kiribati, Laos, Lebanon, Liberia, Mexico, Myanmar, Nicaragua, Niger, Nigeria, Panama, Papua New Guinea, Peru, Philippines, Samoa, Seychelles, Solomon Islands, Sudan, Suriname, Sao Tome and Principe, Taiwan, Thailand, Turkey, Ukraine, Vanuatu, Venezuela, and Vietnam
In addition, Africa, Asia, and South America each set continent-wide record averages for April.
April 2024 was also the warmest April in the ocean average, recorded as 1.16 ± 0.14 °C (2.09 ± 0.24 °F) above the 1850 to 1900 average. This beats the previous record for April by an appreciable margin, though the current uncertainties are significant.
The ocean temperature anomaly for April is similar to other recent months in 2024, but cooler than in July, August, and September 2023.
According to the European ERA5, global ocean average temperatures have now set a daily temperature record during every consecutive day for more than a year. This is due to the combination of El Niño and extremely unusual warmth in the Atlantic. This streak will likely end no later than the middle of 2024 as El Niño dissipates, bringing ocean temperatures below the highs of 2023.
Considered in terms of the average over the last 12 months (May 2023 to April 2024), record warmth has been widespread, especially in the tropics. Large parts of South America, Africa, Southeast Asia, Europe, Canada, and the Atlantic have had a 12-month average that is higher than any previous May to April period. The only region to have significant relative cooling during this period is in Eastern Antarctica.
Causes of Recent Warmth
The record warmth over the last few months has been due firstly to the El Niño condition in the Pacific, which is a form of natural variability associated with short-term swings in global temperature. This short-term change occurs alongside a background of longer-term man-made and other natural changes mostly also favoring warming during the present time.
Firstly, man-made global warming has been raising the Earth’s temperature by about 0.19 °C/decade (0.34 °F/decade). This is a direct consequence of the accumulation of additional greenhouse gases in the atmosphere, especially carbon dioxide. This is the primary factor responsible for long-term warming.
However, this global warming is a gradual process. It does not explain short-term spikes and fluctuations in Earth’s average temperature. The main reason for such spikes is internal variability in the distribution of heat and circulation of the oceans and atmosphere. The largest and most well-known form of short-term internal variability is the El Niño / La Niña cycle originating in the Pacific. During the El Niño phase, global average temperatures tend to be somewhat higher. As a result, record highs for global average temperature tend to be set during El Niño years. Last year, a new El Niño officially began in June after a multiple year period of La Niña. The rapid transition from a moderately strong La Niña to the current El Niño played a large role in the warming of 2023.
In addition to the natural El Niño variability, it is likely that other variability also contributed to recent high temperatures. One area of special interest is the Atlantic Ocean. The Northern Atlantic was persistently warm during the second half of 2023 and remains warm in April, with some regions continuing to set records. In recent months, significant warmth has also expanded in the Southern Atlantic. If these changes were entirely natural, the warming spike in the North Atlantic would be rare. However, in previous discussions, we noted that warm anomalies in the Atlantic are likely to be combination of natural variability and man-made regional warming due to new marine shipping regulations that abruptly reduced maritime sulfur aerosol pollution by ~85%.
The combination of global warming and El Niño are the primary factors responsible for the present high global average temperature. However, other factors may also be playing a role. In particular, the evolution of oceanic heatwaves in the Atlantic and other areas is likely to play a large role in determining the outlook for 2024.
El Niño Outlook
April 2024 saw a significant weakening of the current El Niño event. The current CPC/IRI analysis suggests that El Niño conditions will dissipate around Northern Hemisphere Summer in 2024. The current El Niño has fallen to a weak intensity (after being roughly the 3rd strongest of the last 30 years) and is likely to continue dissipating over the next several months.
The current El Niño is likely moderately boosting global average temperatures during 2024. Due to the lag between the development of El Niño and its full impact being felt on global temperatures, it is plausible that the current El Niño will have a greater impact on global temperatures in 2024 than it did in 2023.
It is now considered likely that a La Niña event will develop late in 2024, this will generate moderately cooler global-average conditions late in 2024. The interplay between the current El Niño, the possibility of a late 2024 La Niña, and unusual conditions in other regions (e.g. warmth in the Atlantic) will contribute to whether 2024 is or is not ultimately warmer than 2023.
Rest of 2024
2024 will very likely be one of the two warmest years since instrumental measurements began. Whether it is the warmest year on record will depend on whether 2024 can maintain its current warmth long enough to exceed the record annual average set in 2023. It is typically true that the second year after an El Niño emerges is warmer than the first, though that is not guaranteed.
The first four months of 2024 started with large anomalies, though this is expected to cool somewhat during the latter part of 2024 as El Niño dissipates and overall conditions return towards the long-term trend.
The statistical approach that we use, looking at conditions in recent months, now believes that 2024 has a 62% chance of being warmer than 2023, slightly better than a coin flip. The ultimate outcome will depend on the evolution of the current El Niño, the possible switch to La Niña late in 2024, and variation in other regions. However, it is very unlikely that 2024 will be any colder than the second warmest year overall.
Estimated Probability of 2024 Annual Average final rankings:
- 1st – 62%
- 2nd – 38%
- 3rd or lower – <1%
This forecast probability of record warmth is largely unchanged from the 59% chance estimated last month.
Individually, we estimate an 85% chance that 2024 has the warmest land-only average measured since 1850. Further, we estimate a 40% chance that 2024 has the warmest ocean-only average. In both cases, the current was set in 2023.
We also consider there to be a 85% chance that 2024 will have an annual-average temperature anomaly more than 1.5 °C (2.7 °F) above our 1850-1900 average. The annual average in 2023 slightly exceeded the 1.5 °C (2.7 °F) threshold in our dataset, and this is likely to occur again in 2024.
Though the IPCC has set a goal to limit global warming to no more than 1.5 °C above the pre-industrial, it must be noted that this goal refers to the long-term average temperature. A few months, or a couple years, warmer than 1.5 °C does not automatically mean that the goal has been exceeded. However, breaching 1.5 °C does serve to emphasize how little time remains to meet this target. Unless sharp reductions in man-made greenhouse gas emissions occur soon, the long-term average is likely to pass 1.5 °C during the 2030s.
