The year ahead looks likely to be the warmest on record – with data going back to the Victorian era – according to the Met Office.
Worldwide, the mean temperature for 2015 should land between 14.52 °C and 14.76 °C, with a central estimate coming in at 14.64 °C. The range is plus or minus two standard deviations.
The long term average, which runs between 1961 and 1990, is 14 °C. More recently (1981 to 2010) that has risen to 14.3 °C.
“Taking into account the range of uncertainty in the forecast, it is very likely that 2015 will be one of the warmest years in a series dating back to 1880,” the Met Office said today.
Last year it estimated that 2014 would see average temperatures of 14.57 °C, which has come in on target levels as far as data – until October – shows. This already puts 2014 as one of the warmest years on record.
“The potential increase in global mean temperature in 2015 is expected to be based on the ongoing warmth of the tropical Pacific Ocean, weak El Nino conditions, the warmth of the Arctic and the ongoing increase in greenhouse gas concentrations,” the Met Office said. “These factors are similar to those that contributed to 2014 being one of the warmest on record.”
The estimates are an average of three main global temperature datasets, compiled by the Met Office and Climatic Research Unit at the University of East Anglia (HadCrut), Noaa National Climatic Data Center (Noaa NCDC) and Nasa Goddard Institute for Space Studies (Nasa Giss).
The chart above shows what the Met Office calls “global average temperature anomalies” – in other words how the temperature compared to long-term averages – over the last 20 years. It's important to note that 2014's data only goes up to October so it could change.