Even 'cool' years now exceed past heat records, climate report warns

An analysis done by Our World in Data finds recent La Niña years are hotter than past El Niño years as world faces global warming challenges

In 2024, the global average temperature reached approximately 1.5 degrees Celsius above pre-industrial levels, marking the warmest year on record. However, it's important to recognise that global temperatures have not risen in a strictly linear fashion; instead, they've shown fluctuations characterised by periodic spikes and dips. 

 

These fluctuations can be understood by El Niño and La Niña, the two climate patterns in the Pacific Ocean that affect global weather. They are opposite phases of the El Niño-Southern Oscillation (ENSO) cycle.

 

An analsysis done by Our World in Data indicates that that the global temperatures during recent La Niña years were warmer than El Niño years just a few decades before, which effectively means that the 'cold years' today are hotter than 'hot years' of the past.

 

 

Understanding ENSO: El Niño and La Niña

 

El Niño: This phase is associated with the warming of sea surface temperatures in the central and eastern tropical Pacific Ocean. El Niño events typically occur every 2 to 7 years and can last between 9 to 12 months. The warming during El Niño leads to alterations in global atmospheric circulation, resulting in warmer global temperatures.

 

La Niña: It is characterised by cooler-than-average sea surface temperatures in the central and eastern tropical Pacific. This phase generally brings about cooler global temperatures.

 

The world transitions between El Niño and La Niña phases every two to seven years, with neutral periods in between where neither phase is dominant. These phases influence global weather patterns and temperature anomalies.

 

ENSO's impact on global temperature trends

 

In their report published on Our World in Data, Veronika Samborska and Hannah Ritchie highlight that the 2023-2024 El Niño event played a crucial role in the temperature anomalies observed during that period. This strong El Niño contributed to the unprecedented global warmth experienced in 2024. 

(Credit: Our World in Data)

  Notably, the influence of ENSO phases on global temperatures is superimposed on the long-term warming trend caused by increased greenhouse gas concentrations. This means that even during La Niña phases, which typically exert a cooling effect, global temperatures remain elevated compared to historical averages. 

(Credit: Our World in Data)

 

Record-breaking climate indicators in 2024

 

Due to ENSO's effect, several climate indicators reached unprecedented levels in 2024. These include:

 

Sea ice extent: February 2024 witnessed global sea ice reaching a record low, with both the Arctic and Antarctic experiencing significant reductions. According to a report in the Guardian, the Arctic's sea ice levels were 8 per cent below average, while the Antarctic saw a 26 per cent reduction. Such declines in sea ice are alarming, as sea ice plays a crucial role in reflecting sunlight and regulating the planet's temperature. 

 

Los Angeles wildfires: The year was marked by a series of extreme weather events, including devastating wildfires in Los Angeles in January 2025. These fires led to the evacuation of 180,000 residents and resulted in significant loss of life and property. 

 

The climate action report comes at a time when the US, under President Donald Trump, has withdrawn from the International Partners Group (IPG), a coalition of developed nations pledging funds to assist developing countries in transitioning from coal to green energy. This decision affects nations such as South Africa, Indonesia, and Vietnam, with South Africa losing over $1 billion in US investment for its energy transition projects.

 

To compound the issue, Trump has reiterated his "drill, baby, drill" rhetoric recently. During his inauguration on January 20, 2025, Trump declared a national "energy emergency" and reiterated his commitment to bolster fossil fuel production, urging US oil and gas companies to enhance energy security and economic strength. "I will reverse it immediately. Immediately. And we will drill, baby, drill," he said.