What is El Nino and why could 2027 be the hottest year on record?

• El Nino describes the warming of sea surface temperatures in the tropical Pacific Ocean, occurring every few years.
• The phenomenon disrupts weather patterns globally, while the last El Nino intensified global heat and led to severe droughts, flooding, marine heatwaves and coral bleaching.
• US meteorologists at the National Oceanic and Atmospheric Administration declared the start of an El Nino event in June, predicting it could last until spring 2027.
• Forecasts have suggested that this El Nino will end up being the strongest on record, while experts have said 2027 could be the hottest year on record as a result of the unprecedented event.
• Dr Nick Dunstone, Met Office science fellow, said: “During large El Nino events significantly more heat is released from the ocean to the atmosphere, leading to an increase in global average temperature, particularly in the calendar year following the winter peak of the El Nino.”