Global temperatures set record levels in the month of June. This is an ominous sign in the climate crisis as 2023 is set to become the warmest year on record.

Preliminary global average temperatures taken so far in June are almost 1 degree Celsius above levels previously recorded for the same month, going back to 1979, according to the Guardian website. Although the month is not yet over and a new record may not be set in June, scientists say there is a pattern of increasing global warming that could lead to this year being the hottest year on record, surpassing 2016.

Long-term warming conditions caused by the burning of fossil fuels will likely provide a further boost of heat through El Niño, a naturally recurring phenomenon where parts of the Pacific Ocean warm, typically causing temperatures to rise around the world.

Last week, the National Oceanic and Atmospheric Administration (Noaa) said that El Niño conditions are now present and will “gradually strengthen” early next year. Michael Mann, a climate scientist at the University of Pennsylvania, said human-caused warming would be exacerbated by an event that typically adds between 0.1C and 0.2C to the overall global temperature.

“The global surface temperature anomaly is at or near record levels right now, and 2023 will almost certainly be the warmest year on record,” Mann said.

According to an update issued by Noaa on Wednesday, the world had its third-warmest May with last month setting a 174-year-old temperature record, with North America and South America both having their warmest Mays on record.

Noaa is more cautious about the prospects for a record annual heat in 2023, putting the chances at around 12%, but has said the year is almost certain to rank in the top 10 warmest years and very likely in the top five.