The clear signs of human-induced climate change reached new heights in 2024, according to the World Meteorological Organization (WMO).

The United Nations (UN) agency said that some of the consequences are "irreversible over hundreds if not thousands of years".

The WMO’s State of the Global Climate report confirmed that 2024 was likely the first calendar year to be more than 1.5°C above the pre-industrial era.

Last year, there was a global mean near-surface temperature of 1.55° which is above the 1850-1900 average, making 2024 the warmest year in the 175-year observational record.

The WMO’s flagship report also showed that atmospheric concentration of carbon dioxide (CO2) are at the highest levels in the last 800,000 years.

Globally each of the past 10 years were individually the 10 warmest years on record, while each of the past eight years has set a new record for ocean heat content.

The 18 lowest Arctic sea-ice extents on record were all in the past 18 years and three lowest Antarctic ice extents were in the past three years.

The largest three-year loss of glacier mass on record occurred in the past three years.

The report shows that the rate of sea level rise has doubled since satellite measurements began.

"Leaders must step up to make it happen seizing the benefits of cheap, clean renewables for their people and economies, with new national climate plans due this year," António Guterres, United Nations secretary-general, said.

The report said that long-term global warming is currently estimated to be between 1.34 and 1.41° compared to the 1850-1900 baseline based on a range of methods – although it noted the uncertainty ranges in global temperature statistics.

“While a single year above 1.5 ° of warming does not indicate that the long-term temperature goals of the Paris Agreement are out of reach, it is a wake-up call that we are increasing the risks to our lives, economies and to the planet,” Celeste Saulo, WMO secretary-general, said.

A WMO team of international experts is examining this further in order to ensure consistent, reliable tracking of long-term global temperature changes to be aligned with the Intergovernmental Panel on Climate Change (IPCC).

The record global temperatures seen in 2023 and broken in 2024 were mainly due to the ongoing rise in greenhouse gas (GHG) emissions, coupled with a shift from a cooling La Nina to warming El Nino event.

The WMO said that extreme weather continues to have devastating consequences around the world.

Tropical cyclones, floods, droughts, and other hazards in 2024 led to the highest number of new displacements recorded for the past 16 years, contributed to worsening food crises, and caused massive economic losses.

The WMO is intensifying efforts to strengthen early warning systems and climate services to help decision-makers and society at large be more resilient to extreme weather and climate.

"We are making progress but need to go further and need to go faster. Only half of all countries worldwide have adequate early warning systems. This must change,” Saulo said.