The global mean temperature breached the 1.5-degree Celsius threshold for an entire year for the first time, the European climate agency said on Thursday.

However, this does not imply a permanent breach of the 1.5-degree Celsius limit specified in the Paris Agreement, as it refers to long-term warming over many years.

Scientists at the European Union's Copernicus Climate Change Service (C3S) also said that the world experienced the warmest January on record.

In fact, every month since June last year has been the warmest such month on record.

They attribute the exceptional warming to the combined effects of El Niño -- a period of abnormal warming of surface waters in the central Pacific Ocean -- and human-caused climate change.

C3S said the global mean temperature for the past 12 months (February 2023-January 2024) was the highest on record and 1.52 degrees Celsius above the 1850-1900 pre-industrial average.

The global average temperature in January was 1.66 degrees Celsius above the January average for 1850-1900, the designated pre-industrial reference period.

With an average temperature of 13.14 degrees Celsius, January 2024 was 0.12 degrees Celsius warmer than the previous warmest January in 2020, the EU's climate agency said.

Samantha Burgess, Deputy Director of C3S, said that "2024 starts with another record-breaking month -- not only is it the warmest January on record but we have also just experienced a 12-month period of more than 1.5 degrees Celsius above the pre-industrial reference period".

"Rapid reductions in greenhouse gas emissions are the only way to stop global temperatures from increasing," she said.

The year 2023 was the warmest on record, with the average global temperature rise compared to pre-industrial levels nearing the 1.5-degree Celsius threshold.

The World Meteorological Organisation in December said 2024 could be worse as "El Niño typically has the greatest impact on global temperature after it peaks." In 2015, countries agreed in Paris to limit the average temperature rise to well below 2 degrees Celsius, and preferably to 1.5 degrees Celsius, compared to pre-industrial levels (1850-1900), to avoid worsening climate impacts.

Long-term data shows earth's global surface temperature has risen by around 1.15 degrees Celsius as compared to pre-industrial levels (1850-1900). The business-as-usual scenario will take the world to a temperature rise of around 3 degrees Celsius by the end of the century, scientists have warned.

To limit global warming to 1.5 degrees Celsius, countries together need to cut down the emissions of planet-warming greenhouse gases like carbon dioxide and methane by 43 per cent by 2030.

At the 28th UN climate conference on climate change in Dubai, nearly 200 countries, for the first time, agreed to transition away from fossil fuels in a "just, orderly, and equitable manner" to avert the worst impacts of climate change.

Climate finance will be the main focus of this year's UN climate conference in Baku’s capital Azerbaijan, where nations have to set a new post-2025 target for raising funds to help developing nations cut emissions and handle the impacts of climate change.

This is tough because rich nations have repeatedly failed to meet their 2009 promise to raise USD 100 billion annually by 2020 to support developing countries.

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